https://wiki.reformrivers.eu/api.php?action=feedcontributions&user=Bbelletti&feedformat=atomREFORM wiki - User contributions [en]2024-03-29T08:08:56ZUser contributionsMediaWiki 1.23.5https://wiki.reformrivers.eu/index.php?title=Effect_of_hydromorphology_on_vegetationEffect of hydromorphology on vegetation2015-06-30T18:23:17Z<p>Bbelletti: </p>
<hr />
<div>[[Category:Tools]] [[Category:Vegetation Models]]<br />
<br />
[[File:VegHymoInteractions_VegProcesses.png|right|thumb|450px| Figure 1. Effects of hydromorphological processes on riparian vegetation. Extracted from Solari et al. (2015)]]<br />
<br />
Among the several abiotic (e.g. water chemistry, light and wind) and biotic (e.g. competition, invasive species) factors that influence riparian vegetation processes, fluvial hydrodynamics (i.e. flow and flood regime, and related processes) plays a significant role in all plant life stages (see Figure 1 and Table 1): dispersal, colonization, recruitment, growth, succession and mortality.<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
[[File:VegHymoInteractions_HymoEffectOnVeg.png|center|thumb|600px| Table 1. Models for the effects of hydromorphodynamics on vegetation. Extracted from Solari et al. (2015)]]<br />
<br />
<br />
Tables 2 to 5 indicate the suitability of the models including the effects of hydromorphology on vegetation (dispersal, recruitment, growth and succession) for the analysis of hydromorphological pressures or the design of restoration measures.<br />
<br />
<br />
* '''Vegetation dispersal'''<br />
[[File:VegHymoInteractions_VegDispersal.png|center|thumb|500px| Table 2. Summary of model characteristics on vegetation dispersal.]]<br />
<br />
<br />
* '''Vegetation recruitment'''<br />
[[File:VegHymoInteractions_VegRecruit.png|center|thumb|500px| Table 3. Summary of model characteristics on vegetation recruitment.]]<br />
<br />
<br />
* '''Vegetation growth'''<br />
[[File:VegHymoInteractions_VegGrowth.png|center|thumb|500px| Table 4. Summary of model characteristics on vegetation growth.]]<br />
<br />
<br />
* '''Vegetation succession'''<br />
[[File:VegHymoInteractions_VegSucc.png|center|thumb|500px| Table 5. Summary of model characteristics on vegetation succession.]]<br />
<br />
<br />
<br />
Key future modelling challenges to improve the understanding of the influence of hydromorphology on riparian vegetation, that also fall within the scope of ecosystem management, are (see also Bornette et al., 2008; Osterkamp and Hupp, 2010; Camporeale et al. 2013; Gurnell, 2014):<br />
<br />
- The spatial and temporal dynamics of soil moisture and water table which influence several stages of plant development (recruitment on new sites, plant survival and growth);<br />
<br />
- The understanding of the impact of stochastic variability of river discharge on vegetation processes and patterns;<br />
<br />
- The development of quantitative ecological models of vegetation succession;<br />
<br />
- The understanding of the response of different vegetation traits to a wide range of physical (fluvial) disturbances;<br />
<br />
- There is a need for models which address riparian plant growth rates at the scale of individuals and by comparing difference propagule responses (e.g. different species);<br />
<br />
- The understanding of the effect of climatic change and related disturbances.</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Effect_of_hydromorphology_on_vegetationEffect of hydromorphology on vegetation2015-06-30T18:22:48Z<p>Bbelletti: </p>
<hr />
<div>[[Category:Tools]] [[Category:Vegetation Models]]<br />
<br />
[[File:VegHymoInteractions_VegProcesses.png|right|thumb|450px| Figure 1. Effects of hydromorphological processes on riparian vegetation. Extracted from Solari et al. (2015)]]<br />
<br />
Among the several abiotic (e.g. water chemistry, light and wind) and biotic (e.g. competition, invasive species) factors that influence riparian vegetation processes, fluvial hydrodynamics (i.e. flow and flood regime, and related processes) plays a significant role in all plant life stages (see Figure 1 and Table 1): dispersal, colonization, recruitment, growth, succession and mortality.<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
[[File:VegHymoInteractions_HymoEffectOnVeg.png|center|thumb|600px| Table 1. Models for the effects of hydromorphodynamics on vegetation. Extracted from Solari et al. (2015)]]<br />
<br />
<br />
Tables 2 to 5 indicate the suitability of the models including the effects of hydromorphology on vegetation (dispersal, recruitment, growth and succession) for the analysis of hydromorphological pressures or the design of restoration measures.<br />
<br />
<br />
* '''Vegetation dispersal'''<br />
[[File:VegHymoInteractions_VegDispersal.png|center|thumb|500px| Table 2. Summary of model characteristics on vegetation dispersal.]]<br />
<br />
<br />
* '''Vegetation recruitment'''<br />
[[File:VegHymoInteractions_VegRecruit.png|center|thumb|500px| Table 3. Summary of model characteristics on vegetation recruitment.]]<br />
<br />
<br />
* '''Vegetation growth'''<br />
[[File:VegHymoInteractions_VegGrowth.png|center|thumb|500px| Table 4. Summary of model characteristics on vegetation growth.]]<br />
<br />
<br />
* '''Vegetation succession'''<br />
[[File:VegHymoInteractions_VegSucc.png|center|thumb|500px| Table 5. Summary of model characteristics on vegetation succession.]]<br />
<br />
<br />
<br />
Key future modelling challenges to improve the understanding of the influence of hydromorphology on riparian vegetation, that also fall within the scope of ecosystem management, are (see also Bornette et al., 2008; Osterkamp and Hupp, 2010; Camporeale et al. 2013; Gurnell, 2014):<br />
<br />
- The spatial and temporal dynamics of soil moisture and water table which influence several stages of plant development (recruitment on new sites, plant survival and growth);<br />
<br />
- The understanding of the impact of stochastic variability of river discharge on vegetation processes and patterns;<br />
<br />
- The development of quantitative ecological models of vegetation succession;<br />
<br />
- The understanding of the response of different vegetation traits to a wide range of physical (fluvial) disturbances;<br />
<br />
- There is a need for models which address riparian plant growth rates at the scale of individuals and by comparing difference propagule responses (e.g. different species);<br />
<br />
- The understanding of the effect of climatic change and related disturbances.</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Effect_of_hydromorphology_on_vegetationEffect of hydromorphology on vegetation2015-06-30T18:22:06Z<p>Bbelletti: </p>
<hr />
<div>[[Category:Tools]] [[Category:Vegetation Models]]<br />
<br />
[[File:VegHymoInteractions_VegProcesses.png|right|thumb|450px| Figure 1. Effects of hydromorphological processes on riparian vegetation. Extracted from Solari et al. (2015)]]<br />
<br />
Among the several abiotic (e.g. water chemistry, light and wind) and biotic (e.g. competition, invasive species) factors that influence riparian vegetation processes, fluvial hydrodynamics (i.e. flow and flood regime, and related processes) plays a significant role in all plant life stages (see Figure 1 and Table 1): dispersal, colonization, recruitment, growth, succession and mortality.<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
[[File:VegHymoInteractions_HymoEffectOnVeg.png|center|thumb|600px| Table 1. Models for the effects of hydromorphodynamics on vegetation. Extracted from Solari et al. (2015)]]<br />
<br />
<br />
Tables 2 to 5 indicate the suitability of the models including the effects of hydromorphology on vegetation (dispersal, recruitment, growth and succession) for the analysis of hydromorphological pressures or the design of restoration measures.<br />
<br />
<br />
* '''Vegetation dispersal'''<br />
[[File:VegHymoInteractions_VegDispersal.png|center|thumb|500px| Table 2. Summary of model characteristics on vegetation dispersal.]]<br />
<br />
<br />
* '''Vegetation recruitment'''<br />
[[File:VegHymoInteractions_VegRecruit.png|center|thumb|500px| Table 3. Summary of model characteristics on vegetation recruitment.]]<br />
<br />
<br />
* '''Vegetation growth'''<br />
[[File:VegHymoInteractions_VegGrowth.png|center|thumb|500px| Table 4. Summary of model characteristics on vegetation growth.]]<br />
<br />
<br />
* '''Vegetation succession'''<br />
[[File:VegHymoInteractions_VegSucc.png|center|thumb|500px| Table 5. Summary of model characteristics on vegetation succession.]]<br />
<br />
<br />
<br />
Key future modelling challenges to improve the understanding of the influence of hydromorphology on riparian vegetation, that also fall within the scope of ecosystem management are (see also Bornette et al., 2008; Osterkamp and Hupp, 2010; Camporeale et al. 2013; Gurnell, 2014):<br />
<br />
- The spatial and temporal dynamics of soil moisture and water table which influence several stages of plant development (recruitment on new sites, plant survival and growth);<br />
<br />
- The understanding of the impact of stochastic variability of river discharge on vegetation processes and patterns;<br />
<br />
- The development of quantitative ecological models of vegetation succession;<br />
<br />
- The understanding of the response of different vegetation traits to a wide range of physical (fluvial) disturbances;<br />
<br />
- There is a need for models which address riparian plant growth rates at the scale of individuals and by comparing difference propagule responses (e.g. different species);<br />
<br />
- The understanding of the effect of climatic change and related disturbances.</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Category:Vegetation_ModelsCategory:Vegetation Models2015-06-30T18:15:07Z<p>Bbelletti: /* Modelling Vegetation-Hydromorphology Interactions */</p>
<hr />
<div>[[Category:Tools]]<br />
<br />
=Modelling Vegetation-Hydromorphology Interactions=<br />
<br />
Here is summarised a review of modelling approaches that can help to investigate aspects of the interaction between plants and physical processes in river environments (see also [[Role_of_vegetation|Role of vegetation]]). Models can support river managers in the management, design and restoration of rivers. The content is taken from Gurnell et al. (2014) (see also Solari et al. 2015).<br />
<br />
Models have been distinguished according to the following topics (Figure 1):<br />
<br />
(i) [[Effect of vegetation on hydromorphodynamics]]. This includes the more complex models generally including advanced hydrology and sediment transport and simple vegetation which are mainly used for engineering purposes. It includes equations and process descriptions for flow resistance, bank erosion and bank accretion.<br />
<br />
(ii) [[Effect of hydromorphology on riparian vegetation]]. This includes ecological models using hydromorphodynamics as environmental variables influencing plant survival, growth, reproduction and dispersal.<br />
<br />
(iii) Large wood. This includes models of breakage, transport and decomposition of large wood.<br />
<br />
(iv) Interaction between vegetation and hydromorphology. This includes several models explicitly including the interaction between vegetation and hydromorphology (topics i and ii combined).<br />
<br />
(v) Vegetation dynamics. This includes models that simulate interactions between plants and predict vegetation patterns in less disturbed environments (e.g. at higher altitudes on the floodplain) as a result of competition and facilitation processes.<br />
<br />
(vi) Interaction between groundwater and vegetation. This includes ecohydrological models with vegetation dynamics.<br />
<br />
[[File:VegHymoInteractions_models_Fig1.png|center|thumb|400px| Figure 1. Interactions between vegetation and hydromorphology. Extracted from Solari et al. (2015).]]<br />
<br />
<br />
For each topic are reported:<br />
<br />
- the usability of the tools for the analysis of hydromorphological pressures and design of restoration measures;<br />
<br />
- future research and modelling challenges.<br />
<br />
==References==<br />
Gurnell A.M., González Del Tánago M., O’Hare M.T., Van Oorschot M., Belletti B., Buijse T., García De Jalón D., Grabowski R., Hendriks D., Mountford O., Rinaldi M., Solari L., Szewczyk M., Vargas-Luna A. (2014). Influence of Natural Hydromorphological Dynamics on Biota and Ecosystem Function. [http://www.reformrivers.eu/system/files/2.2%20Natural%20HyMo%20Biota%20Ecol%20Function%20part%201%20FINAL.pdf REFORM Deliverable 2.2 Part 1, Section 2.3]<br />
<br />
Solari L., Van Oorschot M., Belletti B., Hebdrix D., Rinaldi M., Vargas-Luna A. (2015). Advances on modelling riparian vegetation-hydromorphology interactions. River Research and Applications. DOI: 10.1002/rra.2910</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=File:VegHymoInteractions_HymoEffectOnVeg.pngFile:VegHymoInteractions HymoEffectOnVeg.png2015-06-30T18:14:23Z<p>Bbelletti: </p>
<hr />
<div></div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Effect_of_hydromorphology_on_vegetationEffect of hydromorphology on vegetation2015-06-30T18:11:12Z<p>Bbelletti: </p>
<hr />
<div>[[Category:Tools]] [[Category:Vegetation Models]]<br />
Among the several abiotic (e.g. water chemistry, light and wind) and biotic (e.g. competition, invasive species) factors that influence riparian vegetation processes, fluvial hydrodynamics (i.e. flow and flood regime, and related processes) plays a significant role in all plant life stages (see Figure 1): dispersal, colonization, recruitment, growth, succession and mortality.<br />
<br />
[[File:VegHymoInteractions_VegProcesses.png|center|thumb|500px| Figure 1. Effects of hydromorphological processes on riparian vegetation. Extracted from Solari et al. (2015)]]<br />
<br />
Tables 1 to 4 indicate the suitability of the models including the effects of hydromorphology on vegetation (dispersal, recruitment, growth and succession) for the analysis of hydromorphological pressures or the design of restoration measures.<br />
<br />
<br />
* '''Vegetation dispersal'''<br />
[[File:VegHymoInteractions_VegDispersal.png|center|thumb|500px| Table 1. Summary of model characteristics on vegetation dispersal.]]<br />
<br />
<br />
* '''Vegetation recruitment'''<br />
[[File:VegHymoInteractions_VegRecruit.png|center|thumb|500px| Table 2. Summary of model characteristics on vegetation recruitment.]]<br />
<br />
<br />
* '''Vegetation growth'''<br />
[[File:VegHymoInteractions_VegGrowth.png|center|thumb|500px| Table 3. Summary of model characteristics on vegetation growth.]]<br />
<br />
<br />
* '''Vegetation succession'''<br />
[[File:VegHymoInteractions_VegSucc.png|center|thumb|500px| Table 4. Summary of model characteristics on vegetation succession.]]<br />
<br />
<br />
<br />
Key future modelling challenges to improve the understanding of the influence of hydromorphology on riparian vegetation, that also fall within the scope of ecosystem management are (see also Bornette et al., 2008; Osterkamp and Hupp, 2010; Camporeale et al. 2013; Gurnell, 2014):<br />
<br />
- The spatial and temporal dynamics of soil moisture and water table which influence several stages of plant development (recruitment on new sites, plant survival and growth);<br />
<br />
- The understanding of the impact of stochastic variability of river discharge on vegetation processes and patterns;<br />
<br />
- The development of quantitative ecological models of vegetation succession;<br />
<br />
- The understanding of the response of different vegetation traits to a wide range of physical (fluvial) disturbances;<br />
<br />
- There is a need for models which address riparian plant growth rates at the scale of individuals and by comparing difference propagule responses (e.g. different species);<br />
<br />
- The understanding of the effect of climatic change and related disturbances.</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=File:VegHymoInteractions_VegProcesses.pngFile:VegHymoInteractions VegProcesses.png2015-06-30T18:05:04Z<p>Bbelletti: </p>
<hr />
<div></div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=File:VegHymoInteractions_VegDispersal.pngFile:VegHymoInteractions VegDispersal.png2015-06-30T18:02:46Z<p>Bbelletti: </p>
<hr />
<div></div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Effect_of_hydromorphology_on_vegetationEffect of hydromorphology on vegetation2015-06-30T18:02:05Z<p>Bbelletti: </p>
<hr />
<div>[[Category:Tools]] [[Category:Vegetation Models]]<br />
Among the several abiotic (e.g. water chemistry, light and wind) and biotic (e.g. competition, invasive species) factors that influence riparian vegetation processes, fluvial hydrodynamics (i.e. flow and flood regime, and related processes) plays a significant role in all plant life stages: dispersal, colonization, recruitment, growth, succession and mortality (see Figure 1).<br />
<br />
[[File:VegHymoInteractions_VegDispersal.png|center|thumb|500px| Figure 1. Effects of hydromorphological processes on riparian vegetation. Extracted from Solari et al. (2015)]]<br />
<br />
===Vegetation dispersal===<br />
[[File:VegHymoInteractions_VegDispersal.png|center|thumb|500px| Table 1. Summary of model characteristics on vegetation dispersal.]]<br />
<br />
<br />
===Vegetation recruitment===<br />
[[File:VegHymoInteractions_VegRecruit.png|center|thumb|500px| Table 2. Summary of model characteristics on vegetation recruitment.]]<br />
<br />
<br />
===Vegetation growth===<br />
[[File:VegHymoInteractions_VegGrowth.png|center|thumb|500px| Table 2. Summary of model characteristics on vegetation growth.]]<br />
<br />
<br />
===Vegetation succession===<br />
[[File:VegHymoInteractions_VegSucc.png|center|thumb|500px| Table 2. Summary of model characteristics on vegetation succession.]]<br />
<br />
<br />
===Future modelling challenges===<br />
Key future modelling challenges to improve the understanding of the influence of hydromorphology on riparian vegetation, that also fall within the scope of ecosystem management are (see also Bornette et al., 2008; Osterkamp and Hupp, 2010; Camporeale et al. 2013; Gurnell, 2014):<br />
<br />
- The spatial and temporal dynamics of soil moisture and water table which influence several stages of plant development (recruitment on new sites, plant survival and growth);<br />
<br />
- The understanding of the impact of stochastic variability of river discharge on vegetation processes and patterns;<br />
<br />
- The development of quantitative ecological models of vegetation succession;<br />
<br />
- The understanding of the response of different vegetation traits to a wide range of physical (fluvial) disturbances;<br />
<br />
- There is a need for models which address riparian plant growth rates at the scale of individuals and by comparing difference propagule responses (e.g. different species);<br />
<br />
- The understanding of the effect of climatic change and related disturbances.</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=File:VegHymoInteractions_VegSucc.pngFile:VegHymoInteractions VegSucc.png2015-06-30T17:34:44Z<p>Bbelletti: </p>
<hr />
<div></div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=File:VegHymoInteractions_VegRecruit.pngFile:VegHymoInteractions VegRecruit.png2015-06-30T17:34:27Z<p>Bbelletti: </p>
<hr />
<div></div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=File:VegHymoInteractions_VegGrowth.pngFile:VegHymoInteractions VegGrowth.png2015-06-30T17:34:03Z<p>Bbelletti: </p>
<hr />
<div></div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Effect_of_hydromorphology_on_vegetationEffect of hydromorphology on vegetation2015-06-30T17:29:09Z<p>Bbelletti: Created page with "Category:Tools Category:Vegetation Models File:VegHymoInteractions_VegDispersal.png|center|thumb|500px| Table 1. Summary of model characteristics on vegetation disp..."</p>
<hr />
<div>[[Category:Tools]] [[Category:Vegetation Models]]<br />
<br />
[[File:VegHymoInteractions_VegDispersal.png|center|thumb|500px| Table 1. Summary of model characteristics on vegetation dispersal.]]</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Category:Vegetation_ModelsCategory:Vegetation Models2015-06-30T17:27:37Z<p>Bbelletti: </p>
<hr />
<div>[[Category:Tools]]<br />
<br />
=Modelling Vegetation-Hydromorphology Interactions=<br />
<br />
Here is summarised a review of modelling approaches that can help to investigate aspects of the interaction between plants and physical processes in river environments (see also [[Role_of_vegetation|Role of vegetation]]). Models can support river managers in the management, design and restoration of rivers. The content is taken from Gurnell et al. (2014) (see also Solari et al. 2015).<br />
<br />
Models have been distinguished according to the following topics (Figure 1):<br />
<br />
(i) [[Effect of vegetation on hydromorphodynamics]]. This includes the more complex models generally including advanced hydrology and sediment transport and simple vegetation which are mainly used for engineering purposes. It includes equations and process descriptions for flow resistance, bank erosion and bank accretion.<br />
<br />
(ii) [[Effect of hydromorphology on vegetation]]. This includes ecological models using hydromorphodynamics as environmental variables influencing plant survival, growth, reproduction and dispersal.<br />
<br />
(iii) Large wood. This includes models of breakage, transport and decomposition of large wood.<br />
<br />
(iv) Interaction between vegetation and hydromorphology. This includes several models explicitly including the interaction between vegetation and hydromorphology (topics i and ii combined).<br />
<br />
(v) Vegetation dynamics. This includes models that simulate interactions between plants and predict vegetation patterns in less disturbed environments (e.g. at higher altitudes on the floodplain) as a result of competition and facilitation processes.<br />
<br />
(vi) Interaction between groundwater and vegetation. This includes ecohydrological models with vegetation dynamics.<br />
<br />
[[File:VegHymoInteractions_models_Fig1.png|center|thumb|400px| Figure 1. Interactions between vegetation and hydromorphology. Extracted from Solari et al. (2015).]]<br />
<br />
<br />
For each topic are reported:<br />
<br />
- the usability of the tools for the analysis of hydromorphological pressures and design of restoration measures;<br />
<br />
- future research and modelling challenges.<br />
<br />
==References==<br />
Gurnell A.M., González Del Tánago M., O’Hare M.T., Van Oorschot M., Belletti B., Buijse T., García De Jalón D., Grabowski R., Hendriks D., Mountford O., Rinaldi M., Solari L., Szewczyk M., Vargas-Luna A. (2014). Influence of Natural Hydromorphological Dynamics on Biota and Ecosystem Function. [http://www.reformrivers.eu/system/files/2.2%20Natural%20HyMo%20Biota%20Ecol%20Function%20part%201%20FINAL.pdf REFORM Deliverable 2.2 Part 1, Section 2.3]<br />
<br />
Solari L., Van Oorschot M., Belletti B., Hebdrix D., Rinaldi M., Vargas-Luna A. (2015). Advances on modelling riparian vegetation-hydromorphology interactions. River Research and Applications. DOI: 10.1002/rra.2910</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Effect_of_vegetation_on_hydromorphodynamicsEffect of vegetation on hydromorphodynamics2015-06-30T17:25:56Z<p>Bbelletti: </p>
<hr />
<div>[[Category:Tools]][[Category:Vegetation Models]]<br />
<br />
Vegetation can influence river hydrodynamics by changing the turbulent flow field and the averaged velocity profiles in comparison with those that can be commonly found in<br />
non-vegetated flows. In this way, vegetation potentially has a relevant effect on flow resistance, sediment transport and bank dynamics (see Table 1).<br />
<br />
[[File:VegHymoInteractions_Hydromorphodynamics.png|center|thumb|600px| Table 1. Models for the effects of vegetation on hydromorphodynamics.]]<br />
<br />
<br />
===Vegetation and flow resistance===<br />
Tables 2 summarises the suitability of models with flow resistance for the analysis of hydromorphological pressures or the design of restoration measures.<br />
<br />
[[File:VegHymoInteractions_FlowRes.png|center|thumb|500px| Table 2. Summary of model characteristics on vegetation and flow resistance.]]<br />
<br />
Future research is needed on the following topics:<br />
<br />
- Effect of different types and growth stages of vegetation (rigid or flexible) and different vegetation densities on flow turbulence structure and secondary currents of a stream;<br />
<br />
- Effect of plant reconfiguration with increasing flow velocity on drag;<br />
<br />
- Effect of the spatial distribution of vegetation at a reach scale on flow resistance;<br />
<br />
- Uprooting, breakage of plants during high-flow conditions may give rise to significant changes in flow resistance between the rising and falling limbs of the hydrograph;<br />
<br />
- Develop suitable parameterization to characterize different species.<br />
<br />
<br />
===Vegetation and sediment transport===<br />
Research on the effect of vegetation on sediment transport is needed in relation to the following topics: <br />
- Characterization of turbulent coherent structures in mobile vegetated channels in order to understand flow conditions leading to deposition and substrate stability of a given particle size;<br />
- The impact of spatial variability of vegetation on flow and sediment transport;<br />
- Formulation of models for evaluating sediment transport incorporating the effect of turbulence and vegetation properties.<br />
<br />
<br />
===Vegetation and bank dynamics===<br />
Tables 3 and 4 summarise the suitability of models with bank stability and accretion, respectively, for the analysis of hydromorphological pressures or the design of restoration measures.<br />
<br />
[[File:VegHymoInteractions_BankStab.png|center|thumb|500px| Table 3. Summary of model characteristics on vegetation and bank stability.]]<br />
<br />
[[File:VegHymoInteractions_BankAcc.png|center|thumb|500px| Table 4. Summary of model characteristics on vegetation and bank accretion.]]<br />
<br />
Future research and modelling challenges:<br />
<br />
- More work is needed to better understand the hydrological effects of riparian vegetation and to incorporate them into models of bank erosion and failures.<br />
<br />
- Another area of knowledge gaps concerns modelling interactions of the various erosion processes and mass failures, and the relative role of vegetation on near-bank hydrodynamic flow conditions, erodibility parameters, and shear strength. In order to extend results from a bank profile to a reach and account for variability of hydrodynamic, geotechnical, and vegetational conditions, vegetation should be included into 3-D morphodynamic models.<br />
<br />
- Concerning bank accretion modelling is still in its infancy. Recommendations relate to three main aspects: the inclusion of vegetation dynamics, the influence of the high variability of flows, and the up-scaling of the effects acting at different scales.</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Effect_of_vegetation_on_hydromorphodynamicsEffect of vegetation on hydromorphodynamics2015-06-30T17:25:22Z<p>Bbelletti: /* Vegetation and flow resistance */</p>
<hr />
<div>[[Category:Tools]][[Category:Vegetation Models]]<br />
<br />
Vegetation can influence river hydrodynamics by changing the turbulent flow field and the averaged velocity profiles in comparison with those that can be commonly found in<br />
non-vegetated flows. In this way, vegetation potentially has a relevant effect on flow resistance, sediment transport and bank dynamics (see Table 1).<br />
<br />
[[File:VegHymoInteractions_Hydromorphodynamics.png|center|thumb|600px| Table 1. Models for the effects of vegetation on hydromorphodynamics.]]<br />
<br />
<br />
===Vegetation and flow resistance===<br />
Tables 2 summarises the suitability of models with flow resistance for the analysis of hydromorphological pressures or the design of restoration measures.<br />
<br />
[[File:VegHymoInteractions_FlowRes.png|center|thumb|500px| Table 2. Summary of model characteristics on vegetation and flow resistance.]]<br />
<br />
Future research is needed on the following topics:<br />
<br />
- Effect of different types and growth stages of vegetation (rigid or flexible) and different vegetation densities on flow turbulence structure and secondary currents of a stream;<br />
<br />
- Effect of plant reconfiguration with increasing flow velocity on drag;<br />
<br />
- Effect of the spatial distribution of vegetation at a reach scale on flow resistance;<br />
<br />
- Uprooting, breakage of plants during high-flow conditions may give rise to significant changes in flow resistance between the rising and falling limbs of the hydrograph;<br />
<br />
- Develop suitable parameterization to characterize different species.<br />
<br />
<br />
===Vegetation and sediment transport===<br />
Research on the effect of vegetation on sediment transport is needed in relation to the following topics: <br />
- Characterization of turbulent coherent structures in mobile vegetated channels in order to understand flow conditions leading to deposition and substrate stability of a given particle size;<br />
- The impact of spatial variability of vegetation on flow and sediment transport;<br />
- Formulation of models for evaluating sediment transport incorporating the effect of turbulence and vegetation properties.<br />
<br />
===Vegetation and bank dynamics===<br />
Tables 3 and 4 summarise the suitability of models with bank stability and accretion, respectively, for the analysis of hydromorphological pressures or the design of restoration measures.<br />
<br />
[[File:VegHymoInteractions_BankStab.png|center|thumb|500px| Table 3. Summary of model characteristics on vegetation and bank stability.]]<br />
<br />
[[File:VegHymoInteractions_BankAcc.png|center|thumb|500px| Table 4. Summary of model characteristics on vegetation and bank accretion.]]<br />
<br />
Future research and modelling challenges:<br />
<br />
- More work is needed to better understand the hydrological effects of riparian vegetation and to incorporate them into models of bank erosion and failures.<br />
<br />
- Another area of knowledge gaps concerns modelling interactions of the various erosion processes and mass failures, and the relative role of vegetation on near-bank hydrodynamic flow conditions, erodibility parameters, and shear strength. In order to extend results from a bank profile to a reach and account for variability of hydrodynamic, geotechnical, and vegetational conditions, vegetation should be included into 3-D morphodynamic models.<br />
<br />
- Concerning bank accretion modelling is still in its infancy. Recommendations relate to three main aspects: the inclusion of vegetation dynamics, the influence of the high variability of flows, and the up-scaling of the effects acting at different scales.</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Effect_of_vegetation_on_hydromorphodynamicsEffect of vegetation on hydromorphodynamics2015-06-30T17:22:17Z<p>Bbelletti: </p>
<hr />
<div>[[Category:Tools]][[Category:Vegetation Models]]<br />
<br />
Vegetation can influence river hydrodynamics by changing the turbulent flow field and the averaged velocity profiles in comparison with those that can be commonly found in<br />
non-vegetated flows. In this way, vegetation potentially has a relevant effect on flow resistance, sediment transport and bank dynamics (see Table 1).<br />
<br />
[[File:VegHymoInteractions_Hydromorphodynamics.png|center|thumb|600px| Table 1. Models for the effects of vegetation on hydromorphodynamics.]]<br />
<br />
<br />
===Vegetation and flow resistance===<br />
Tables 2 summarises the suitability of models with flow resistance for the analysis of hydromorphological pressures or the design of restoration measures.<br />
<br />
[[File:VegHymoInteractions_FlowRes.png|center|thumb|500px| Table 2. Summary of model characteristics on vegetation and flow resistance.]]<br />
<br />
Future research is needed on the following topics:<br />
<br />
- Effect of different types and growth stages of vegetation (rigid or flexible) and different vegetation densities on flow turbulence structure and secondary currents of a stream;<br />
<br />
- Effect of plant reconfiguration with increasing flow velocity on drag;<br />
<br />
- Effect of the spatial distribution of vegetation at a reach scale on flow resistance;<br />
<br />
- Uprooting, breakage of plants during high-flow conditions may give rise to significant changes in flow resistance between the rising and falling limbs of the hydrograph;<br />
<br />
- Develop suitable parameterization to characterize different species.<br />
<br />
<br />
===Vegetation and bank dynamics===<br />
Tables 3 and 4 summarise the suitability of models with bank stability and accretion, respectively, for the analysis of hydromorphological pressures or the design of restoration measures.<br />
<br />
[[File:VegHymoInteractions_BankStab.png|center|thumb|500px| Table 3. Summary of model characteristics on vegetation and bank stability.]]<br />
<br />
[[File:VegHymoInteractions_BankAcc.png|center|thumb|500px| Table 4. Summary of model characteristics on vegetation and bank accretion.]]<br />
<br />
Future research and modelling challenges:<br />
<br />
- More work is needed to better understand the hydrological effects of riparian vegetation and to incorporate them into models of bank erosion and failures.<br />
<br />
- Another area of knowledge gaps concerns modelling interactions of the various erosion processes and mass failures, and the relative role of vegetation on near-bank hydrodynamic flow conditions, erodibility parameters, and shear strength. In order to extend results from a bank profile to a reach and account for variability of hydrodynamic, geotechnical, and vegetational conditions, vegetation should be included into 3-D morphodynamic models.<br />
<br />
- Concerning bank accretion modelling is still in its infancy. Recommendations relate to three main aspects: the inclusion of vegetation dynamics, the influence of the high variability of flows, and the up-scaling of the effects acting at different scales.</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Effect_of_vegetation_on_hydromorphodynamicsEffect of vegetation on hydromorphodynamics2015-06-30T17:20:31Z<p>Bbelletti: </p>
<hr />
<div>[[Category:Tools]][[Category:Vegetation Models]]<br />
<br />
Vegetation can influence river hydrodynamics by changing the turbulent flow field and the averaged velocity profiles in comparison with those that can be commonly found in<br />
non-vegetated flows. In this way, vegetation potentially has a relevant effect on flow resistance, sediment transport and bank dynamics (see Table 1).<br />
<br />
[[File:VegHymoInteractions_Hydromorphodynamics.png|center|thumb|600px| Table 1. Models for the effects of vegetation on hydromorphodynamics.]]<br />
<br />
===Vegetation and flow resistance===<br />
<br />
[[File:VegHymoInteractions_FlowRes.png|center|thumb|500px| Table 2. Summary of model characteristics on vegetation and flow resistance.]]<br />
<br />
Future research is needed on the following topics:<br />
<br />
- effect of different types and growth stages of vegetation (rigid or flexible) and different vegetation densities on flow turbulence structure and secondary currents of a stream;<br />
<br />
- effect of plant reconfiguration with increasing flow velocity on drag;<br />
<br />
- effect of the spatial distribution of vegetation at a reach scale on flow resistance;<br />
<br />
- uprooting, breakage of plants during high-flow conditions may give rise to significant changes in flow resistance between the rising and falling limbs of the hydrograph;<br />
<br />
- develop suitable parameterization to characterize different species.<br />
<br />
<br />
===Vegetation and bank dynamics===<br />
Tables 3 and 4 summarise the suitability of models with bank stability and accretion, respectively, for the analysis of hydromorphological pressures or the design of restoration measures.<br />
<br />
[[File:VegHymoInteractions_BankStab.png|center|thumb|500px| Table 3. Summary of model characteristics on vegetation and bank stability.]]<br />
<br />
[[File:VegHymoInteractions_BankAcc.png|center|thumb|500px| Table 4. Summary of model characteristics on vegetation and bank accretion.]]<br />
<br />
Future research and modelling challenges:<br />
<br />
- More work is needed to better understand the hydrological effects of riparian vegetation and to incorporate them into models of bank erosion and failures.<br />
<br />
- Another area of knowledge gaps concerns modelling interactions of the various erosion processes and mass failures, and the relative role of vegetation on near-bank hydrodynamic flow conditions, erodibility parameters, and shear strength. In order to extend results from a bank profile to a reach and account for variability of hydrodynamic, geotechnical, and vegetational conditions, vegetation should be included into 3-D morphodynamic models.<br />
<br />
- Concerning bank accretion modelling is still in its infancy. Recommendations relate to three main aspects: the inclusion of vegetation dynamics, the influence of the high variability of flows, and the up-scaling of the effects acting at different scales.</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Effect_of_vegetation_on_hydromorphodynamicsEffect of vegetation on hydromorphodynamics2015-06-30T17:19:46Z<p>Bbelletti: /* Vegetation and bank dynamics */</p>
<hr />
<div>[[Category:Tools]][[Category:Vegetation Models]]<br />
<br />
Vegetation can influence river hydrodynamics by changing the turbulent flow field and the averaged velocity profiles in comparison with those that can be commonly found in<br />
non-vegetated flows. In this way, vegetation potentially has a relevant effect on flow resistance, sediment transport and bank dynamics (see Table 1).<br />
<br />
[[File:VegHymoInteractions_Hydromorphodynamics.png|center|thumb|500px| Table 1. Models for the effects of vegetation on hydromorphodynamics.]]<br />
<br />
===Vegetation and flow resistance===<br />
<br />
[[File:VegHymoInteractions_FlowRes.png|center|thumb|500px| Table 2. Summary of model characteristics on vegetation and flow resistance.]]<br />
<br />
Future research is needed on the following topics:<br />
<br />
- effect of different types and growth stages of vegetation (rigid or flexible) and different vegetation densities on flow turbulence structure and secondary currents of a stream;<br />
<br />
- effect of plant reconfiguration with increasing flow velocity on drag;<br />
<br />
- effect of the spatial distribution of vegetation at a reach scale on flow resistance;<br />
<br />
- uprooting, breakage of plants during high-flow conditions may give rise to significant changes in flow resistance between the rising and falling limbs of the hydrograph;<br />
<br />
- develop suitable parameterization to characterize different species.<br />
<br />
<br />
===Vegetation and bank dynamics===<br />
Tables 3 and 4 summarise the suitability of models with bank stability and accretion, respectively, for the analysis of hydromorphological pressures or the design of restoration measures.<br />
<br />
[[File:VegHymoInteractions_BankStab.png|center|thumb|500px| Table 3. Summary of model characteristics on vegetation and bank stability.]]<br />
<br />
[[File:VegHymoInteractions_BankAcc.png|center|thumb|500px| Table 4. Summary of model characteristics on vegetation and bank accretion.]]<br />
<br />
Future research and modelling challenges:<br />
<br />
- More work is needed to better understand the hydrological effects of riparian vegetation and to incorporate them into models of bank erosion and failures.<br />
<br />
- Another area of knowledge gaps concerns modelling interactions of the various erosion processes and mass failures, and the relative role of vegetation on near-bank hydrodynamic flow conditions, erodibility parameters, and shear strength. In order to extend results from a bank profile to a reach and account for variability of hydrodynamic, geotechnical, and vegetational conditions, vegetation should be included into 3-D morphodynamic models.<br />
<br />
- Concerning bank accretion modelling is still in its infancy. Recommendations relate to three main aspects: the inclusion of vegetation dynamics, the influence of the high variability of flows, and the up-scaling of the effects acting at different scales.</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Effect_of_vegetation_on_hydromorphodynamicsEffect of vegetation on hydromorphodynamics2015-06-30T17:06:06Z<p>Bbelletti: </p>
<hr />
<div>[[Category:Tools]][[Category:Vegetation Models]]<br />
<br />
Vegetation can influence river hydrodynamics by changing the turbulent flow field and the averaged velocity profiles in comparison with those that can be commonly found in<br />
non-vegetated flows. In this way, vegetation potentially has a relevant effect on flow resistance, sediment transport and bank dynamics (see Table 1).<br />
<br />
[[File:VegHymoInteractions_Hydromorphodynamics.png|center|thumb|500px| Table 1. Models for the effects of vegetation on hydromorphodynamics.]]<br />
<br />
===Vegetation and flow resistance===<br />
<br />
[[File:VegHymoInteractions_FlowRes.png|center|thumb|500px| Table 2. Summary of model characteristics on vegetation and flow resistance.]]<br />
<br />
Future research is needed on the following topics:<br />
<br />
- effect of different types and growth stages of vegetation (rigid or flexible) and different vegetation densities on flow turbulence structure and secondary currents of a stream;<br />
<br />
- effect of plant reconfiguration with increasing flow velocity on drag;<br />
<br />
- effect of the spatial distribution of vegetation at a reach scale on flow resistance;<br />
<br />
- uprooting, breakage of plants during high-flow conditions may give rise to significant changes in flow resistance between the rising and falling limbs of the hydrograph;<br />
<br />
- develop suitable parameterization to characterize different species.<br />
<br />
<br />
===Vegetation and bank dynamics===</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=File:VegHymoInteractions_BankStab.pngFile:VegHymoInteractions BankStab.png2015-06-30T16:58:22Z<p>Bbelletti: </p>
<hr />
<div></div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=File:VegHymoInteractions_BankAcc.pngFile:VegHymoInteractions BankAcc.png2015-06-30T16:57:59Z<p>Bbelletti: </p>
<hr />
<div></div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=File:VegHymoInteractions_Hydromorphodynamics.pngFile:VegHymoInteractions Hydromorphodynamics.png2015-06-30T16:57:08Z<p>Bbelletti: </p>
<hr />
<div></div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Effect_of_vegetation_on_hydromorphodynamicsEffect of vegetation on hydromorphodynamics2015-06-30T16:52:52Z<p>Bbelletti: </p>
<hr />
<div>[[Category:Tools]][[Category:Vegetation Models]]<br />
<br />
Vegetation can influence river hydrodynamics by changing the turbulent flow field and the averaged velocity profiles in comparison with those that can be commonly found in<br />
non-vegetated flows. In this way, vegetation potentially has a relevant effect on flow resistance, sediment transport and bank dynamics.<br />
<br />
[[File:VegHymoInteractions_FlowRes.png|center|thumb|500px| Table 2. Summary of model characteristics on vegetation and flow resistance.]]</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Effect_of_vegetation_on_hydromorphodynamicsEffect of vegetation on hydromorphodynamics2015-06-30T16:51:46Z<p>Bbelletti: </p>
<hr />
<div>[[Category:Tools]][[Category:Vegetation Models]]<br />
<br />
Vegetation can influence river hydrodynamics by changing the turbulent flow field and the averaged velocity profiles in comparison with those that can be commonly found in<br />
non-vegetated flows. In this way, vegetation potentially has a relevant effect on flow resistance, sediment transport and bank dynamics.<br />
<br />
[[File:VegHymoInteractions_FlowRes.png|center|thumb|400px| Table 2. Summary of model characteristics on vegetation and flow resistance.]]</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=File:VegHymoInteractions_FlowRes.pngFile:VegHymoInteractions FlowRes.png2015-06-30T16:48:05Z<p>Bbelletti: </p>
<hr />
<div></div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Effect_of_vegetation_on_hydromorphodynamicsEffect of vegetation on hydromorphodynamics2015-06-30T16:27:18Z<p>Bbelletti: </p>
<hr />
<div>[[Category:Tools]][[Category:Vegetation Models]]<br />
<br />
Vegetation can influence river hydrodynamics by changing the turbulent flow field and the averaged velocity profiles in comparison with those that can be commonly found in<br />
non-vegetated flows. In this way, vegetation potentially has a relevant effect on flow resistance, sediment transport and bank dynamics.</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Effect_of_vegetation_on_hydromorphodynamicsEffect of vegetation on hydromorphodynamics2015-06-30T16:24:36Z<p>Bbelletti: </p>
<hr />
<div>[[Category: Vegetation Models]]<br />
Vegetation can influence river hydrodynamics by changing the turbulent flow field and the averaged velocity profiles in comparison with those that can be commonly found in<br />
non-vegetated flows. In this way, vegetation potentially has a relevant effect on flow resistance, sediment transport and bank dynamics.</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Effect_of_vegetation_on_hydromorphodynamicsEffect of vegetation on hydromorphodynamics2015-06-30T16:20:42Z<p>Bbelletti: Created page with "Vegetation can influence river hydrodynamics by changing the turbulent flow field and the averaged velocity profiles in comparison with those that can be commonly found in non..."</p>
<hr />
<div>Vegetation can influence river hydrodynamics by changing the turbulent flow field and the averaged velocity profiles in comparison with those that can be commonly found in<br />
non-vegetated flows. In this way, vegetation potentially has a relevant effect on flow resistance, sediment transport and bank dynamics.</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Category:Vegetation_ModelsCategory:Vegetation Models2015-06-30T16:13:07Z<p>Bbelletti: /* Modelling Vegetation-Hydromorphology Interactions */</p>
<hr />
<div>[[Category:Tools]]<br />
<br />
=Modelling Vegetation-Hydromorphology Interactions=<br />
<br />
Here is summarised a review of modelling approaches that can help to investigate aspects of the interaction between plants and physical processes in river environments (see also [[Role_of_vegetation|Role of vegetation]]). Models can support river managers in the management, design and restoration of rivers. The content is taken from Gurnell et al. (2014) (see also Solari et al. 2015).<br />
<br />
Models have been distinguished according to the following topics (Figure 1):<br />
<br />
(i) [[Effect of vegetation on hydromorphodynamics]]. This includes the more complex models generally including advanced hydrology and sediment transport and simple vegetation which are mainly used for engineering purposes. It includes equations and process descriptions for flow resistance, bank erosion and bank accretion.<br />
<br />
(ii) Effect of hydromorphology on vegetation. This includes ecological models using hydromorphodynamics as environmental variables influencing plant survival, growth, reproduction and dispersal.<br />
<br />
(iii) Large wood. This includes models of breakage, transport and decomposition of large wood.<br />
<br />
(iv) Interaction between vegetation and hydromorphology. This includes several models explicitly including the interaction between vegetation and hydromorphology (topics i and ii combined).<br />
<br />
(v) Vegetation dynamics. This includes models that simulate interactions between plants and predict vegetation patterns in less disturbed environments (e.g. at higher altitudes on the floodplain) as a result of competition and facilitation processes.<br />
<br />
(vi) Interaction between groundwater and vegetation. This includes ecohydrological models with vegetation dynamics.<br />
<br />
[[File:VegHymoInteractions_models_Fig1.png|center|thumb|400px| Figure 1. Interactions between vegetation and hydromorphology. Extracted from Solari et al. (2015).]]<br />
<br />
<br />
For each topic are reported:<br />
<br />
- the usability of the tools for the analysis of hydromorphological pressures and design of restoration measures;<br />
<br />
- future research and modelling challenges.<br />
<br />
==References==<br />
Gurnell A.M., González Del Tánago M., O’Hare M.T., Van Oorschot M., Belletti B., Buijse T., García De Jalón D., Grabowski R., Hendriks D., Mountford O., Rinaldi M., Solari L., Szewczyk M., Vargas-Luna A. (2014). Influence of Natural Hydromorphological Dynamics on Biota and Ecosystem Function. [http://www.reformrivers.eu/system/files/2.2%20Natural%20HyMo%20Biota%20Ecol%20Function%20part%201%20FINAL.pdf REFORM Deliverable 2.2 Part 1, Section 2.3]<br />
<br />
Solari L., Van Oorschot M., Belletti B., Hebdrix D., Rinaldi M., Vargas-Luna A. (2015). Advances on modelling riparian vegetation-hydromorphology interactions. River Research and Applications. DOI: 10.1002/rra.2910</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Category:Vegetation_ModelsCategory:Vegetation Models2015-06-30T16:10:04Z<p>Bbelletti: /* Modelling Vegetation-Hydromorphology Interactions */</p>
<hr />
<div>[[Category:Tools]]<br />
<br />
=Modelling Vegetation-Hydromorphology Interactions=<br />
<br />
Here is summarised a review of modelling approaches that can help to investigate aspects of the interaction between plants and physical processes in river environments (see also [[Role_of_vegetation|Role of vegetation]]). Models can support river managers in the management, design and restoration of rivers. The content is taken from Gurnell et al. (2014) (see also Solari et al. 2015).<br />
<br />
Models have been distinguished according to the following topics (Figure 1):<br />
<br />
(i) [[Effect of vegetation on hydromorphology]]. This includes the more complex models generally including advanced hydrology and sediment transport and simple vegetation which are mainly used for engineering purposes. It includes equations and process descriptions for flow resistance, bank erosion and bank accretion.<br />
<br />
(ii) Effect of hydromorphology on vegetation. This includes ecological models using hydromorphodynamics as environmental variables influencing plant survival, growth, reproduction and dispersal.<br />
<br />
(iii) Large wood. This includes models of breakage, transport and decomposition of large wood.<br />
<br />
(iv) Interaction between vegetation and hydromorphology. This includes several models explicitly including the interaction between vegetation and hydromorphology (topics i and ii combined).<br />
<br />
(v) Vegetation dynamics. This includes models that simulate interactions between plants and predict vegetation patterns in less disturbed environments (e.g. at higher altitudes on the floodplain) as a result of competition and facilitation processes.<br />
<br />
(vi) Interaction between groundwater and vegetation. This includes ecohydrological models with vegetation dynamics.<br />
<br />
[[File:VegHymoInteractions_models_Fig1.png|center|thumb|400px| Figure 1. Interactions between vegetation and hydromorphology. Extracted from Solari et al. (2015).]]<br />
<br />
<br />
For each topic are reported:<br />
<br />
- the usability of the tools for the analysis of hydromorphological pressures and design of restoration measures;<br />
<br />
- future research and modelling challenges.<br />
<br />
==References==<br />
Gurnell A.M., González Del Tánago M., O’Hare M.T., Van Oorschot M., Belletti B., Buijse T., García De Jalón D., Grabowski R., Hendriks D., Mountford O., Rinaldi M., Solari L., Szewczyk M., Vargas-Luna A. (2014). Influence of Natural Hydromorphological Dynamics on Biota and Ecosystem Function. [http://www.reformrivers.eu/system/files/2.2%20Natural%20HyMo%20Biota%20Ecol%20Function%20part%201%20FINAL.pdf REFORM Deliverable 2.2 Part 1, Section 2.3]<br />
<br />
Solari L., Van Oorschot M., Belletti B., Hebdrix D., Rinaldi M., Vargas-Luna A. (2015). Advances on modelling riparian vegetation-hydromorphology interactions. River Research and Applications. DOI: 10.1002/rra.2910</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Category:Vegetation_ModelsCategory:Vegetation Models2015-06-30T15:28:14Z<p>Bbelletti: /* Modelling Vegetation-Hydromorphology Interactions */</p>
<hr />
<div>[[Category:Tools]]<br />
<br />
=Modelling Vegetation-Hydromorphology Interactions=<br />
<br />
Here is summarised a review of modelling approaches that can help to investigate aspects of the interaction between plants and physical processes in river environments (see also [[Role_of_vegetation|Role of vegetation]]). Models can support river managers in the management, design and restoration of rivers. The content is taken from Gurnell et al. (2014) (see also Solari et al. 2015).<br />
<br />
Models have been distinguished according to the following topics (Figure 1):<br />
<br />
(i) Effect of vegetation on hydromorphology. This includes the more complex models generally including advanced hydrology and sediment transport and simple vegetation which are mainly used for engineering purposes. It includes equations and process descriptions for flow resistance, bank erosion and bank accretion.<br />
<br />
(ii) Effect of hydromorphology on vegetation. This includes ecological models using hydromorphodynamics as environmental variables influencing plant survival, growth, reproduction and dispersal.<br />
<br />
(iii) Large wood. This includes models of breakage, transport and decomposition of large wood.<br />
<br />
(iv) Interaction between vegetation and hydromorphology. This includes several models explicitly including the interaction between vegetation and hydromorphology (topics i and ii combined).<br />
<br />
(v) Vegetation dynamics. This includes models that simulate interactions between plants and predict vegetation patterns in less disturbed environments (e.g. at higher altitudes on the floodplain) as a result of competition and facilitation processes.<br />
<br />
(vi) Interaction between groundwater and vegetation. This includes ecohydrological models with vegetation dynamics.<br />
<br />
[[File:VegHymoInteractions_models_Fig1.png|center|thumb|400px| Figure 1. Interactions between vegetation and hydromorphology. Extracted from Solari et al. (2015).]]<br />
<br />
<br />
For each topic are reported:<br />
<br />
- the usability of the tools for the analysis of hydromorphological pressures and design of restoration measures;<br />
<br />
- future research and modelling challenges.<br />
<br />
==References==<br />
Gurnell A.M., González Del Tánago M., O’Hare M.T., Van Oorschot M., Belletti B., Buijse T., García De Jalón D., Grabowski R., Hendriks D., Mountford O., Rinaldi M., Solari L., Szewczyk M., Vargas-Luna A. (2014). Influence of Natural Hydromorphological Dynamics on Biota and Ecosystem Function. [http://www.reformrivers.eu/system/files/2.2%20Natural%20HyMo%20Biota%20Ecol%20Function%20part%201%20FINAL.pdf REFORM Deliverable 2.2 Part 1, Section 2.3]<br />
<br />
Solari L., Van Oorschot M., Belletti B., Hebdrix D., Rinaldi M., Vargas-Luna A. (2015). Advances on modelling riparian vegetation-hydromorphology interactions. River Research and Applications. DOI: 10.1002/rra.2910</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Category:Vegetation_ModelsCategory:Vegetation Models2015-06-30T15:21:39Z<p>Bbelletti: /* References */</p>
<hr />
<div>[[Category:Tools]]<br />
<br />
=Modelling Vegetation-Hydromorphology Interactions=<br />
<br />
Models can support river managers in the management, design and restoration of rivers. Here is summarised a review of modelling approaches that can help to investigate aspects of the interaction between plants and physical processes in river environments (see also [[Role_of_vegetation|Role of vegetation]]). The content is taken from Gurnell et al. (2014) (see also Solari et al. 2015).<br />
<br />
Models have been distinguished according to the following topics (Figure 1):<br />
<br />
(i) Effect of vegetation on hydromorphology. This includes the more complex models generally including advanced hydrology and sediment transport and simple vegetation which are mainly used for engineering purposes. It includes equations and process descriptions for flow resistance, bank erosion and bank accretion.<br />
<br />
(ii) Effect of hydromorphology on vegetation. This includes ecological models using hydromorphodynamics as environmental variables influencing plant survival, growth, reproduction and dispersal.<br />
<br />
(iii) Large wood. This includes models of breakage, transport and decomposition of large wood.<br />
<br />
(iv) Interaction between vegetation and hydromorphology. This includes several models explicitly including the interaction between vegetation and hydromorphology (topics i and ii combined).<br />
<br />
(v) Vegetation dynamics. This includes models that simulate interactions between plants and predict vegetation patterns in less disturbed environments (e.g. at higher altitudes on the floodplain) as a result of competition and facilitation processes.<br />
<br />
(vi) Interaction between groundwater and vegetation. This includes ecohydrological models with vegetation dynamics.<br />
<br />
[[File:VegHymoInteractions_models_Fig1.png|center|thumb|400px| Figure 1. Interactions between vegetation and hydromorphology. Extracted from Solari et al. (2015).]]<br />
<br />
<br />
For each topic are reported:<br />
<br />
- the usability of the tools for the analysis of hydromorphological pressures and design of restoration measures;<br />
<br />
- future research and modelling challenges.<br />
<br />
==References==<br />
Gurnell A.M., González Del Tánago M., O’Hare M.T., Van Oorschot M., Belletti B., Buijse T., García De Jalón D., Grabowski R., Hendriks D., Mountford O., Rinaldi M., Solari L., Szewczyk M., Vargas-Luna A. (2014). Influence of Natural Hydromorphological Dynamics on Biota and Ecosystem Function. [http://www.reformrivers.eu/system/files/2.2%20Natural%20HyMo%20Biota%20Ecol%20Function%20part%201%20FINAL.pdf REFORM Deliverable 2.2 Part 1, Section 2.3]<br />
<br />
Solari L., Van Oorschot M., Belletti B., Hebdrix D., Rinaldi M., Vargas-Luna A. (2015). Advances on modelling riparian vegetation-hydromorphology interactions. River Research and Applications. DOI: 10.1002/rra.2910</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Category:Vegetation_ModelsCategory:Vegetation Models2015-06-30T15:17:02Z<p>Bbelletti: /* Modelling Vegetation-Hydromorphology Interactions */</p>
<hr />
<div>[[Category:Tools]]<br />
<br />
=Modelling Vegetation-Hydromorphology Interactions=<br />
<br />
Models can support river managers in the management, design and restoration of rivers. Here is summarised a review of modelling approaches that can help to investigate aspects of the interaction between plants and physical processes in river environments (see also [[Role_of_vegetation|Role of vegetation]]). The content is taken from Gurnell et al. (2014) (see also Solari et al. 2015).<br />
<br />
Models have been distinguished according to the following topics (Figure 1):<br />
<br />
(i) Effect of vegetation on hydromorphology. This includes the more complex models generally including advanced hydrology and sediment transport and simple vegetation which are mainly used for engineering purposes. It includes equations and process descriptions for flow resistance, bank erosion and bank accretion.<br />
<br />
(ii) Effect of hydromorphology on vegetation. This includes ecological models using hydromorphodynamics as environmental variables influencing plant survival, growth, reproduction and dispersal.<br />
<br />
(iii) Large wood. This includes models of breakage, transport and decomposition of large wood.<br />
<br />
(iv) Interaction between vegetation and hydromorphology. This includes several models explicitly including the interaction between vegetation and hydromorphology (topics i and ii combined).<br />
<br />
(v) Vegetation dynamics. This includes models that simulate interactions between plants and predict vegetation patterns in less disturbed environments (e.g. at higher altitudes on the floodplain) as a result of competition and facilitation processes.<br />
<br />
(vi) Interaction between groundwater and vegetation. This includes ecohydrological models with vegetation dynamics.<br />
<br />
[[File:VegHymoInteractions_models_Fig1.png|center|thumb|400px| Figure 1. Interactions between vegetation and hydromorphology. Extracted from Solari et al. (2015).]]<br />
<br />
<br />
For each topic are reported:<br />
<br />
- the usability of the tools for the analysis of hydromorphological pressures and design of restoration measures;<br />
<br />
- future research and modelling challenges.<br />
<br />
==References==<br />
[http://www.reformrivers.eu/system/files/2.2%20Natural%20HyMo%20Biota%20Ecol%20Function%20part%201%20FINAL.pdf Section 2.3 of the REFORM Deliverable 2.2 Part 1]<br />
<br />
Solari L., Van Oorschot M., Belletti B., Hebdrix D., Rinaldi M., Vargas-Luna A. (2015). Advances on modelling riparian vegetation-hydromorphology interactions. River Research and Applications. DOI: 10.1002/rra.2910</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Category:Vegetation_ModelsCategory:Vegetation Models2015-06-30T15:12:49Z<p>Bbelletti: /* Modelling Vegetation-Hydromorphology Interactions */</p>
<hr />
<div>[[Category:Tools]]<br />
<br />
=Modelling Vegetation-Hydromorphology Interactions=<br />
<br />
Models can support river managers in the management, design and restoration of rivers. Here is summarised a review of modelling approaches that can help to investigate aspects of the interaction between plants and physical processes in river environments (see also [[Role_of_vegetation|Role of vegetation]]). The content is taken from section 3.4 of the Deliverable 2.2 (see also Solari et al. 2015).<br />
<br />
Models have been distinguished according to the following topics (Figure 1):<br />
<br />
(i) Effect of vegetation on hydromorphology. This includes the more complex models generally including advanced hydrology and sediment transport and simple vegetation which are mainly used for engineering purposes. It includes equations and process descriptions for flow resistance, bank erosion and bank accretion.<br />
<br />
(ii) Effect of hydromorphology on vegetation. This includes ecological models using hydromorphodynamics as environmental variables influencing plant survival, growth, reproduction and dispersal.<br />
<br />
(iii) Large wood. This includes models of breakage, transport and decomposition of large wood.<br />
<br />
(iv) Interaction between vegetation and hydromorphology. This includes several models explicitly including the interaction between vegetation and hydromorphology (topics i and ii combined).<br />
<br />
(v) Vegetation dynamics. This includes models that simulate interactions between plants and predict vegetation patterns in less disturbed environments (e.g. at higher altitudes on the floodplain) as a result of competition and facilitation processes.<br />
<br />
(vi) Interaction between groundwater and vegetation. This includes ecohydrological models with vegetation dynamics.<br />
<br />
[[File:VegHymoInteractions_models_Fig1.png|center|thumb|400px| Figure 1. Interactions between vegetation and hydromorphology. Extracted from Solari et al. 2015]]<br />
<br />
<br />
For each topic are reported:<br />
<br />
- the usability of the tools for the analysis of hydromorphological pressures and design of restoration measures;<br />
<br />
- future research and modelling challenges.<br />
<br />
==References==<br />
[http://www.reformrivers.eu/system/files/2.2%20Natural%20HyMo%20Biota%20Ecol%20Function%20part%201%20FINAL.pdf Section 2.3 of the REFORM Deliverable 2.2 Part 1]<br />
<br />
Solari L., Van Oorschot M., Belletti B., Hebdrix D., Rinaldi M., Vargas-Luna A. (2015). Advances on modelling riparian vegetation-hydromorphology interactions. River Research and Applications. DOI: 10.1002/rra.2910</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Role_of_vegetationRole of vegetation2015-06-30T15:10:45Z<p>Bbelletti: </p>
<hr />
<div>[[File:Luca Solari role of vegetation 1.jpg|thumb|300px|right|Figure 1: The Tagliamento river (Italy); riparian plants grow on the sediment bars in the middle of the river and along the river margins.]]<br />
<br />
Vegetation is a key element in rivers. Riparian vegetation (such as herbaceous plants, shrubs and trees) can be found on sediment deposits, on banks and along river margins (see the examples in Figure 1 and 2), while aquatic vegetation grows in or near water. <br />
<br /><br /><br />
<br />
[[File:Luca Solari role of vegetation 2.jpg|thumb|300px|right|Figure 2: The Cecina river (Italy); riparian plants (herbaceous plants, shrubs and trees) colonize the sediment deposit, the floodplain and the banks while woody debris (dead trees) are deposited in the main channel.]]<br />
<br />
In river systems, vegetation interacts with hydromorphology in different ways:<br />
* river hydromorphology plays a significant role in all plant life stages, from seed dispersal to colonization, recruitment, growth, succession and mortality. Successful riparian plants often adopt a combination of adaptive strategies during different life stages in order to ensure their survival. Examples are high dispersal rates, adaptations to resist stress, and vegetative reproduction;<br />
* vegetation actively interacts with river hydromorphology. Above-ground plant biomass can affect the flow, by blocking it or changing flow resistance and sediment transport, for instance inducing sediment deposition. Below-ground plant biomass modifies the hydraulic and mechanical properties of the substrate, including the sediments retained by the above-ground biomass, and consequently the moisture regime and erodibility of the soil on the river bed and on banks. <br />
Plants therefore can actively interact with river morphology by changing river bed topography, river planform shape and bed sediment composition, and by promoting the development of distinctive vegetated landforms. <br />
<br /><br /><br />
<br />
Although there is still much to be learnt about the interactions between plants and hydromorphology, various models are available in the scientific and technical literature for the interpretation of these interactions. Examples are models for evaluating the effect of vegetation on flow resistance, river bank dynamics, river bed development and river planform evolution (see also [[:Category:Vegetation_Models|Vegetation Models]]).<br />
<br /><br />
<br /><br />
More details on the recent advances on modelling riparian vegetation - hydromorphology interactions can be found in:<br />
* [http://www.reformrivers.eu/system/files/2.2%20Natural%20HyMo%20Biota%20Ecol%20Function%20part%201%20FINAL.pdf Chapter 2 of the REFORM Deliverable 2.2 Part 1];<br />
* Solari L, Van Oorschot M, Belletti B, Hendriks D, Rinaldi M, and Vargas-Luna A. 2015. Advances on modelling riparian vegetation – hydromorphology interactions. River Research and applications. DOI:10.1002/rra.2910;<br />
* Gurnell AM., O’Hare MT., Corenblit D., García de Jalón D., González del Tánago M., Grabowski M., and Szewczyk RC. 2015. A conceptual model of vegetation-hydrogeomorphology interactions within river corridors. River Research and applications. …….<br />
* [http://onlinelibrary.wiley.com/doi/10.1002/esp.3397/abstract Gurnell AM. 2014. Plants as river ecosystem engineers. Earth Surface Processes and Landforms 39(1): 4–25. DOI: 10.1002/esp.3397];</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Category:Vegetation_ModelsCategory:Vegetation Models2015-06-30T15:08:47Z<p>Bbelletti: /* Modelling Vegetation-Hydromorphology Interactions */</p>
<hr />
<div>[[Category:Tools]]<br />
<br />
=Modelling Vegetation-Hydromorphology Interactions=<br />
<br />
Models can support river managers in the management, design and restoration of rivers. Here is summarised a review of modelling approaches that can help to investigate aspects of the interaction between plants and physical processes in river environments (see also [[Role_of_vegetation|Role of vegetation]]). The content is taken from section 3.4 of the Deliverable 2.2 (see also Solari et al. 2015).<br />
<br />
Models have been distinguished according to the following topics (Figure 1):<br />
<br />
(i) Effect of vegetation on hydromorphology. This includes the more complex models generally including advanced hydrology and sediment transport and simple vegetation which are mainly used for engineering purposes. It includes equations and process descriptions for flow resistance, bank erosion and bank accretion.<br />
<br />
(ii) Effect of hydromorphology on vegetation. This includes ecological models using hydromorphodynamics as environmental variables influencing plant survival, growth, reproduction and dispersal.<br />
<br />
(iii) Large wood. This includes models of breakage, transport and decomposition of large wood.<br />
<br />
(iv) Interaction between vegetation and hydromorphology. This includes several models explicitly including the interaction between vegetation and hydromorphology (topics i and ii combined).<br />
<br />
(v) Vegetation dynamics. This includes models that simulate interactions between plants and predict vegetation patterns in less disturbed environments (e.g. at higher altitudes on the floodplain) as a result of competition and facilitation processes.<br />
<br />
(vi) Interaction between groundwater and vegetation. This includes ecohydrological models with vegetation dynamics.<br />
<br />
[[File:VegHymoInteractions_models_Fig1.png|center|thumb|400px| Figure 1. Interactions between vegetation and hydromorphology. Extracted from Solari et al. 2015]]<br />
<br />
<br />
For each topic are listed:<br />
- the usability of the tools for the analysis of hydromorphological pressures and design of restoration measures;<br />
- future research and modelling challenges.<br />
<br />
==References==<br />
[http://www.reformrivers.eu/system/files/2.2%20Natural%20HyMo%20Biota%20Ecol%20Function%20part%201%20FINAL.pdf Section 2.3 of the REFORM Deliverable 2.2 Part 1]<br />
<br />
Solari L., Van Oorschot M., Belletti B., Hebdrix D., Rinaldi M., Vargas-Luna A. (2015). Advances on modelling riparian vegetation-hydromorphology interactions. River Research and Applications. DOI: 10.1002/rra.2910</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Role_of_vegetationRole of vegetation2015-06-30T15:05:53Z<p>Bbelletti: </p>
<hr />
<div>[[File:Luca Solari role of vegetation 1.jpg|thumb|300px|right|Figure 1: The Tagliamento river (Italy); riparian plants grow on the sediment bars in the middle of the river and along the river margins.]]<br />
<br />
Vegetation is a key element in rivers. Riparian vegetation (such as herbaceous plants, shrubs and trees) can be found on sediment deposits, on banks and along river margins (see the examples in Figure 1 and 2), while aquatic vegetation grows in or near water. <br />
<br /><br /><br />
<br />
[[File:Luca Solari role of vegetation 2.jpg|thumb|300px|right|Figure 2: The Cecina river (Italy); riparian plants (herbaceous plants, shrubs and trees) colonize the sediment deposit, the floodplain and the banks while woody debris (dead trees) are deposited in the main channel.]]<br />
<br />
In river systems, vegetation interacts with hydromorphology in different ways:<br />
* river hydromorphology plays a significant role in all plant life stages, from seed dispersal to colonization, recruitment, growth, succession and mortality. Successful riparian plants often adopt a combination of adaptive strategies during different life stages in order to ensure their survival. Examples are high dispersal rates, adaptations to resist stress, and vegetative reproduction;<br />
* vegetation actively interacts with river hydromorphology. Above-ground plant biomass can affect the flow, by blocking it or changing flow resistance and sediment transport, for instance inducing sediment deposition. Below-ground plant biomass modifies the hydraulic and mechanical properties of the substrate, including the sediments retained by the above-ground biomass, and consequently the moisture regime and erodibility of the soil on the river bed and on banks. <br />
Plants therefore can actively interact with river morphology by changing river bed topography, river planform shape and bed sediment composition, and by promoting the development of distinctive vegetated landforms. <br />
<br /><br /><br />
<br />
Although there is still much to be learnt about the interactions between plants and hydromorphology, various models are available in the scientific and technical literature for the interpretation of these interactions. Examples are models for evaluating the effect of vegetation on flow resistance, river bank dynamics, river bed development and river planform evolution (see also [[:Category:Vegetation_Models]]).<br />
<br /><br />
<br /><br />
More details on the recent advances on modelling riparian vegetation - hydromorphology interactions can be found in:<br />
* [http://www.reformrivers.eu/system/files/2.2%20Natural%20HyMo%20Biota%20Ecol%20Function%20part%201%20FINAL.pdf Chapter 2 of the REFORM Deliverable 2.2 Part 1];<br />
* Solari L, Van Oorschot M, Belletti B, Hendriks D, Rinaldi M, and Vargas-Luna A. 2015. Advances on modelling riparian vegetation – hydromorphology interactions. River Research and applications. DOI:10.1002/rra.2910;<br />
* Gurnell AM., O’Hare MT., Corenblit D., García de Jalón D., González del Tánago M., Grabowski M., and Szewczyk RC. 2015. A conceptual model of vegetation-hydrogeomorphology interactions within river corridors. River Research and applications. …….<br />
* [http://onlinelibrary.wiley.com/doi/10.1002/esp.3397/abstract Gurnell AM. 2014. Plants as river ecosystem engineers. Earth Surface Processes and Landforms 39(1): 4–25. DOI: 10.1002/esp.3397];</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Category:Vegetation_ModelsCategory:Vegetation Models2015-06-30T15:01:18Z<p>Bbelletti: /* Modelling Vegetation-Hydromorphology Interactions */</p>
<hr />
<div>[[Category:Tools]]<br />
<br />
=Modelling Vegetation-Hydromorphology Interactions=<br />
<br />
Models can support river managers in the management, design and restoration of rivers. Here is summarised a review of modelling approaches that can help to investigate aspects of the interaction between plants and physical processes in river environments (see also [[:Category:Role_of_vegetation|Role of vegetation]]). The content is taken from section 3.4 of the Deliverable 2.2 (see also Solari et al. 2015).<br />
<br />
Models have been distinguished according to the following topics (Figure 1):<br />
<br />
(i) Effect of vegetation on hydromorphology. This includes the more complex models generally including advanced hydrology and sediment transport and simple vegetation which are mainly used for engineering purposes. It includes equations and process descriptions for flow resistance, bank erosion and bank accretion.<br />
<br />
(ii) Effect of hydromorphology on vegetation. This includes ecological models using hydromorphodynamics as environmental variables influencing plant survival, growth, reproduction and dispersal.<br />
<br />
(iii) Large wood. This includes models of breakage, transport and decomposition of large wood.<br />
<br />
(iv) Interaction between vegetation and hydromorphology. This includes several models explicitly including the interaction between vegetation and hydromorphology (topics i and ii combined).<br />
<br />
(v) Vegetation dynamics. This includes models that simulate interactions between plants and predict vegetation patterns in less disturbed environments (e.g. at higher altitudes on the floodplain) as a result of competition and facilitation processes.<br />
<br />
(vi) Interaction between groundwater and vegetation. This includes ecohydrological models with vegetation dynamics.<br />
<br />
[[File:VegHymoInteractions_models_Fig1.png|center|thumb|400px| Figure 1. Interactions between vegetation and hydromorphology. Extracted from Solari et al. 2015]]<br />
<br />
<br />
For each topic are listed:<br />
- the usability of the tools for the analysis of hydromorphological pressures and design of restoration measures;<br />
- future research and modelling challenges.<br />
<br />
==References==<br />
[http://www.reformrivers.eu/system/files/2.2%20Natural%20HyMo%20Biota%20Ecol%20Function%20part%201%20FINAL.pdf Section 2.3 of the REFORM Deliverable 2.2 Part 1]<br />
<br />
Solari L., Van Oorschot M., Belletti B., Hebdrix D., Rinaldi M., Vargas-Luna A. (2015). Advances on modelling riparian vegetation-hydromorphology interactions. River Research and Applications. DOI: 10.1002/rra.2910</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Introduction_to_characterisation:_Multi-scale_Hierarchical_FrameworkIntroduction to characterisation: Multi-scale Hierarchical Framework2015-06-30T14:59:15Z<p>Bbelletti: /* Hydromorphological characterisation */</p>
<hr />
<div>== Hydromorphological characterisation ==<br />
Effective river restoration calls for an understanding of how rivers work. A key step for this is hydromorphological characterization, looking at rivers from a perspective that discloses the relevant processes and forms. Hydromorphology is a matter of water and sediment, but also of vegetation interacting with water and sediment. This makes both geomorphological and ecological processes relevant.<br />
<br />
River management often focuses on individual reaches of river networks. However, the character and dynamism of river reaches depends not only upon natural processes and human interventions within the reach, but also within the catchment, particularly upstream of the reach (see Figure 1). The character of river reaches often responds to processes and interventions across the catchment in a delayed way as changes in processes propagate from their source areas through the river network to individual reaches.<br />
<br />
A river is a connected ecosystem generated by hydrological, geomorphological and ecological processes that interact at many temporal and spatial scales. Hydromorphological characterization aims at capturing and explaining this complexity (see [[:Category:River_Characterisation|River Characterisation]]). This is the key step in developing a fuller understanding of how a river functions physically, as a foundation for evaluating river conditions and developing a programme of restoration measures.<br />
<br />
The spatial organization of rivers and the way how such spatial organization evolves through time create the variety of forms and processes we observe in nature. This builds the theoretical framework (see [[:Category:River_Characterisation#Multi-scale_Hierarchical_Framework|Multi-scale_Hierarchical_Framework]]) for characterizing relevant spatial and temporal scales at which key fluvial processes occur.<br />
<br />
== How are river systems organized in space? ==<br />
<br />
When thinking about a river, we usually imagine a reach of a few kilometres in length. This is the key spatial scale within a framework of spatial components of the river landscape (see Figure 1). For characterizing the full complexity of rivers, however, it is useful to consider components larger and smaller than a reach too. A hierarchical framework for this helps in adopting the relevant spatial scales to describe specific river system characteristics (see [[:Category:River_Characterisation#The_Framework|The_Framework]]).<br />
<br />
[[File:RiverCharacterisation_Figure1_last.png|center|thumb|600px| Figure 1. The spatial units and scales of the REFORM hierachical framework (Photo credits: Google Earth; University of Florence; F. Comiti (Free University of Bozen))]]<br />
<br />
The hierarchical framework proposes eight different sizes of spatial unit (see [[:Category:River_Characterisation#Hierarchy_of_spatial_units|Hierarchy_of_spatial_units]]) to investigate different river features. Seven of them are represented in Figure 1. The catchment unit encloses the land that is drained by a river and its tributaries, for which the area is typically 10<sup>2</sup>-10<sup>5</sup> km<sup>2</sup>. Landscape units are portions of the catchment that show different forms of physical landscape that can be summarised by properties such as land surface elevation, land steepness, and valley density. They have a typical area of 10<sup>2</sup>-10<sup>3</sup> km<sup>2</sup>. The segment unit is a section of the river system that is located within a valley of sufficiently uniform gradient and width, so that the river is confined by its valley to a similar degree and has similar energy through the segment. River segments are typically 10<sup>1</sup>-10<sup>2</sup> km long.<br />
<br />
The reach unit is a section of the river network in which not only the valley and flow energy are relatively uniform, but also other conditions, such as bed sediments, bank properties and riparian vegetation. This uniformity in conditions gives the river reach a consistent appearance through its length as a result of a near-consistent internal set of process-form interactions. A reach unit is typically 10<sup>-1</sup>-10<sup>1</sup> km in length, and a river segment can contain one to several reaches.<br />
<br />
A geomorphic unit is a portion of a reach that contains a landform created by erosion or deposition of sediment, sometimes in association with vegetation, with a typical length of 10<sup>0</sup>-10<sup>2</sup> m. Geomorphic units can be located within the channel (bed and mid-channel features), along the channel edges (marginal and bank features) or on the floodplain. A hydraulic unit is a spatially distinct patch of relatively homogeneous surface flow and substrate character with a typical size of 10<sup>-1</sup>-10<sup>1</sup> m. A single geomorphic unit can include one to several hydraulic units. River elements include individuals and patches of sediment particles, plants, and wood (10<sup>-2</sup>-10<sup>-1</sup> km). The framework is hierarchical in that each of the spatial units nests within one another so that their boundaries do not overlap.<br />
<br />
Each unit represents a particular spatial scale that is suited to investigating specific processes, human pressures and forms that eventually impact on the character and dynamics of river reach units (see [[:Category:River_Characterisation#Four_stages_of_river_characterization|Four_stages_of_river_characterization]]: [[:Category:River_Characterisation#Stage_1:_Delineation_of_spatial_units|Stage_1_(Delineation_of_spatial_units)]] and [[:Category:River_Characterisation#Stage_2:_Characterisation_of_current_and_past_condition|Stage_2_(Characterising_current_condition)]]).<br />
<br />
Figure 2 lists some examples of indicators of processes, human pressures and forms which can be calculated for each spatial unit (see [[:Category:River_Characterisation#Stage_3:_Indicators|Stage_3:_Indicators]]).<br />
<br />
[[File:RiverCharacterisation_Figure2_last.png|center|thumb|600px| Figure 2. Examples of relevant indicators of processes, human pressures and forms for each spatial unit (Photo credits: Google Earth; University of Florence; F. Comiti (Free University of Bozen))]]<br />
<br />
At the catchment scale, for example, it is relevant to monitor land cover type because it affects run-off production. At the landscape unit scale, potential sources of sediment (for instance gullies, landslides) can be located to estimate the likely supply of such sediment to smaller units. The segment scale is suitable to investigate physical pressures altering longitudinal connectivity, riparian corridor features, valley features and river flow regimes. All of these can be assumed to be fairly homogenous at this scale and thus well-represented by summary indicators. At the reach scale, indicators summarising channel dimensions and type, bank and bed sediments, and riparian properties can be represented by informative indicators. Within reach units, geomorphic units such as riffles, bars or islands can be identified and at a finer scale specific hydraulic units and river elements can be surveyed.<br />
<br />
It is at the reach scale that the many features found across floodplains and river channels adjust to the cascade of influences that propagate to the reach from larger spatial units and scales. This is also the scale that is affected by interactions and feedbacks within the reach among fluvial processes, geomorphic units, hydraulic units, and smaller river elements such as sediment particles, logs, and plants.<br />
<br />
== How do river systems develop in time? ==<br />
<br />
The temporal dimension is necessary for a complete characterization of river processes. This adds knowledge about the changes in features and indicators through time within each spatial unit, and so discloses information that helps to explain how changes occur at different spatial scales and dynamically interact between scales (see [[:Category:River_Characterisation#Characterising_past_condition_and_quantifying_rates_of_processes|Stage_2:_Characterising_past_condition]]). The historical evolution of hydromorphological features and human interventions may be quite different among catchments and may influence river forms and processes in different ways in different catchment environments. Thus, the identification of possible changes in controlling variables forms a basis for the assessment of current and past conditions, as well as for the prediction of future scenarios. Changes through time can be investigated in their historical context, for instance over the last century for changes at catchment to reach scales. A resolution of about 10 to 20 years is suited to the reach scale and below (Figure 3). Proper characterization of historical and contemporary changes at the relevant spatial scales is essential for diagnosing river problems and designing sustainable restoration measures.<br />
<br />
[[File:RiverCharacterisation_Figure3_last.png|center|thumb|600px| Figure 3. Example of the temporal dimension within spatial units, scales, processes and indicators (Photo credits: Google Earth; Archivio Cartografico Provincia di La Spezia, Italy; Istituto Geografico Militare, Italy; University of Florence; P. Vezza (Politecnico di Torino, Italy))]]<br />
<br />
Figure 3 illustrates the changing processes monitored and their temporal scale for each spatial unit in an example catchment. Land cover change over more than 50 years is shown at the catchment scale. Significant land cover and management alterations have occurred over this period throughout Europe, and have affected runoff production and consequently the entire cascade of river processes that drive river hydromorphology and features within the catchment. At the landscape unit scale, afforestation of a valley is illustrated. Extension of forest land cover stabilizes hill slopes and decreases runoff production, leading to a reduction in soil erosion and the supply of sediment to river channel. Such changes in the delivery of water and sediment lead to changes in the size and the form of a river. Sometimes even the type of river is changed. The segment scale illustrates an increase over the last century in infrastructure that directly impacts the river and it processes. Dams disconnect the down-river movement of sediment, often leading to a sediment deficit downstream the dam and degradation of the river bed. Bank protection limits lateral movement of the river and its capacity to erode bank sediment.<br />
<br />
The effects of the installation of river infrastructures that decrease sediment supply and constrain river channel movements are most clearly seen at the reach scale. In the example river reach, a river that was multi-thread braided in the 1950s has been transformed into a single-thread sinuous river accompanied by a severe reduction in the width of the active channel. Changes are also observed in the geomorphic units, with encroachment of vegetation incorporating an island into the floodplain within a period of ten years. At the hydraulic unit scale, the example illustrates the impact of changes in river stage on unit character, even when the river channel form has not changed. At the river element scale, the example shows significant changes in the type and distribution of elements present as the result of a single flood, which has redistributed them within and between river reaches.<br />
<br />
The integration of spatial characteristics and their changes through time allows the investigator to identify which spatial units and temporal scales drive the relevant forms and processes. The hierarchical framework provides an integrated and scientifically sound basis for diagnosing causes and effects of the hydromorphological process cascade (see [[:Category:River_Characterisation#Stage_4:_Interpreting_condition,_trajectories_of_change,_and_sensitivity|Stage_4]]). This process-based characterization is suitable to support river restoration from basin-scale planning to the implementation of local projects.<br />
<br />
== Additional information ==<br />
More details on river hydromorphological characterisation can be found in the [[media: Deliverable2_1.pdf | REFORM Deliverable 2.1]] and the REFORM Deliverable 6.2.</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Category:Vegetation_ModelsCategory:Vegetation Models2015-06-30T14:58:07Z<p>Bbelletti: /* Modelling Vegetation-Hydromorphology Interactions */</p>
<hr />
<div>[[Category:Tools]]<br />
<br />
=Modelling Vegetation-Hydromorphology Interactions=<br />
<br />
Models can support river managers in the management, design and restoration of rivers. Here is summarised a review of modelling approaches that can help to investigate aspects of the interaction between plants and physical processes in river environments (see also [[:Category:Role_of_vegetation|Role of vegetation]]). The content is taken from section 3.4 of the Deliverable 2.2 (see also Solari et al. 2015).<br />
<br />
Models have been distinguished according to the following topics (Figure 1):<br />
<br />
(i) Effect of vegetation on hydromorphology. This includes the more complex models generally including advanced hydrology and sediment transport and simple vegetation which are mainly used for engineering purposes. It includes equations and process descriptions for flow resistance, bank erosion and bank accretion.<br />
<br />
(ii) Effect of hydromorphology on vegetation. This includes ecological models using hydromorphodynamics as environmental variables influencing plant survival, growth, reproduction and dispersal.<br />
<br />
(iii) Large wood. This includes models of breakage, transport and decomposition of large wood.<br />
<br />
(iv) Interaction between vegetation and hydromorphology. This includes several models explicitly including the interaction between vegetation and hydromorphology (topics i and ii combined).<br />
<br />
(v) Vegetation dynamics. This includes models that simulate interactions between plants and predict vegetation patterns in less disturbed environments (e.g. at higher altitudes on the floodplain) as a result of competition and facilitation processes.<br />
<br />
(vi) Interaction between groundwater and vegetation. This includes ecohydrological models with vegetation dynamics.<br />
<br />
[[File:VegHymoInteractions_models_Fig1.png|center|thumb|400px| Figure 1. Interactions between vegetation and hydromorphology.]]<br />
<br />
<br />
For each topic are listed:<br />
- the usability of the tools for the analysis of hydromorphological pressures and design of restoration measures;<br />
- future research and modelling challenges.<br />
<br />
==References==<br />
[http://www.reformrivers.eu/system/files/2.2%20Natural%20HyMo%20Biota%20Ecol%20Function%20part%201%20FINAL.pdf Section 2.3 of the REFORM Deliverable 2.2 Part 1]<br />
<br />
Solari L., Van Oorschot M., Belletti B., Hebdrix D., Rinaldi M., Vargas-Luna A. (2015). Advances on modelling riparian vegetation-hydromorphology interactions. River Research and Applications. DOI: 10.1002/rra.2910</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Category:Vegetation_ModelsCategory:Vegetation Models2015-06-30T14:52:16Z<p>Bbelletti: /* References */</p>
<hr />
<div>[[Category:Tools]]<br />
<br />
=Modelling Vegetation-Hydromorphology Interactions=<br />
<br />
Models can support river managers in the management, design and restoration of rivers. Here is summarised a review of modelling approaches that can help to investigate aspects of the interaction between plants and physical processes in river environments. The content is taken from section 3.4 of the Deliverable 2.2 (see also Solari et al. 2015).<br />
<br />
Models have been distinguished according to the following topics (Figure 1):<br />
<br />
(i) Effect of vegetation on hydromorphology. This includes the more complex models generally including advanced hydrology and sediment transport and simple vegetation which are mainly used for engineering purposes. It includes equations and process descriptions for flow resistance, bank erosion and bank accretion.<br />
<br />
(ii) Effect of hydromorphology on vegetation. This includes ecological models using hydromorphodynamics as environmental variables influencing plant survival, growth, reproduction and dispersal.<br />
<br />
(iii) Large wood. This includes models of breakage, transport and decomposition of large wood.<br />
<br />
(iv) Interaction between vegetation and hydromorphology. This includes several models explicitly including the interaction between vegetation and hydromorphology (topics i and ii combined).<br />
<br />
(v) Vegetation dynamics. This includes models that simulate interactions between plants and predict vegetation patterns in less disturbed environments (e.g. at higher altitudes on the floodplain) as a result of competition and facilitation processes.<br />
<br />
(vi) Interaction between groundwater and vegetation. This includes ecohydrological models with vegetation dynamics.<br />
<br />
[[File:VegHymoInteractions_models_Fig1.png|center|thumb|400px| Figure 1. Interactions between vegetation and hydromorphology.]]<br />
<br />
<br />
For each topic are listed:<br />
- the usability of the tools for the analysis of hydromorphological pressures and design of restoration measures;<br />
- future research and modelling challenges.<br />
<br />
==References==<br />
[http://www.reformrivers.eu/system/files/2.2%20Natural%20HyMo%20Biota%20Ecol%20Function%20part%201%20FINAL.pdf Section 2.3 of the REFORM Deliverable 2.2 Part 1]<br />
<br />
Solari L., Van Oorschot M., Belletti B., Hebdrix D., Rinaldi M., Vargas-Luna A. (2015). Advances on modelling riparian vegetation-hydromorphology interactions. River Research and Applications. DOI: 10.1002/rra.2910</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Category:Vegetation_ModelsCategory:Vegetation Models2015-06-30T14:39:46Z<p>Bbelletti: /* Modelling Vegetation-Hydromorphology Interactions */</p>
<hr />
<div>[[Category:Tools]]<br />
<br />
=Modelling Vegetation-Hydromorphology Interactions=<br />
<br />
Models can support river managers in the management, design and restoration of rivers. Here is summarised a review of modelling approaches that can help to investigate aspects of the interaction between plants and physical processes in river environments. The content is taken from section 3.4 of the Deliverable 2.2 (see also Solari et al. 2015).<br />
<br />
Models have been distinguished according to the following topics (Figure 1):<br />
<br />
(i) Effect of vegetation on hydromorphology. This includes the more complex models generally including advanced hydrology and sediment transport and simple vegetation which are mainly used for engineering purposes. It includes equations and process descriptions for flow resistance, bank erosion and bank accretion.<br />
<br />
(ii) Effect of hydromorphology on vegetation. This includes ecological models using hydromorphodynamics as environmental variables influencing plant survival, growth, reproduction and dispersal.<br />
<br />
(iii) Large wood. This includes models of breakage, transport and decomposition of large wood.<br />
<br />
(iv) Interaction between vegetation and hydromorphology. This includes several models explicitly including the interaction between vegetation and hydromorphology (topics i and ii combined).<br />
<br />
(v) Vegetation dynamics. This includes models that simulate interactions between plants and predict vegetation patterns in less disturbed environments (e.g. at higher altitudes on the floodplain) as a result of competition and facilitation processes.<br />
<br />
(vi) Interaction between groundwater and vegetation. This includes ecohydrological models with vegetation dynamics.<br />
<br />
[[File:VegHymoInteractions_models_Fig1.png|center|thumb|400px| Figure 1. Interactions between vegetation and hydromorphology.]]<br />
<br />
<br />
For each topic are listed:<br />
- the usability of the tools for the analysis of hydromorphological pressures and design of restoration measures;<br />
- future research and modelling challenges.<br />
<br />
==References==<br />
Solari L., Van Oorschot M., Belletti B., Hebdrix D., Rinaldi M., Vargas-Luna A. (2015). Advances on modelling riparian vegetation-hydromorphology interactions. River Research and Applications. DOI: 10.1002/rra.2910</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Category:Vegetation_ModelsCategory:Vegetation Models2015-06-30T14:39:01Z<p>Bbelletti: </p>
<hr />
<div>[[Category:Tools]]<br />
<br />
=Modelling Vegetation-Hydromorphology Interactions=<br />
<br />
Models can support river managers in the management, design and restoration of rivers. Here is summarised a review of modelling approaches that can help to investigate aspects of the interaction between plants and physical processes in river environments. The content is taken from section 3.4 of the Deliverable 2.2 (see also Solari et al. 2015).<br />
<br />
Models have been distinguished according to the following topics (Figure 1):<br />
(i) Effect of vegetation on hydromorphology. This includes the more complex models generally including advanced hydrology and sediment transport and simple vegetation which are mainly used for engineering purposes. It includes equations and process descriptions for flow resistance, bank erosion and bank accretion.<br />
<br />
(ii) Effect of hydromorphology on vegetation. This includes ecological models using hydromorphodynamics as environmental variables influencing plant survival, growth, reproduction and dispersal.<br />
<br />
(iii) Large wood. This includes models of breakage, transport and decomposition of large wood.<br />
<br />
(iv) Interaction between vegetation and hydromorphology. This includes several models explicitly including the interaction between vegetation and hydromorphology (topics i and ii combined).<br />
<br />
(v) Vegetation dynamics. This includes models that simulate interactions between plants and predict vegetation patterns in less disturbed environments (e.g. at higher altitudes on the floodplain) as a result of competition and facilitation processes.<br />
<br />
(vi) Interaction between groundwater and vegetation. This includes ecohydrological models with vegetation dynamics.<br />
<br />
[[File:VegHymoInteractions_models_Fig1.png|center|thumb|400px| Figure 1. Interactions between vegetation and hydromorphology.]]<br />
<br />
<br />
For each topic are listed:<br />
- the usability of the tools for the analysis of hydromorphological pressures and design of restoration measures;<br />
- future research and modelling challenges.<br />
<br />
==References==<br />
Solari L., Van Oorschot M., Belletti B., Hebdrix D., Rinaldi M., Vargas-Luna A. (2015). Advances on modelling riparian vegetation-hydromorphology interactions. River Research and Applications. DOI: 10.1002/rra.2910</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Category:Vegetation_ModelsCategory:Vegetation Models2015-06-30T14:37:45Z<p>Bbelletti: /* Modelling Vegetation-Hydromorphology Interactions */</p>
<hr />
<div>[[Category:Tools]]<br />
<br />
=Modelling Vegetation-Hydromorphology Interactions=<br />
<br />
Models can support river managers in the management, design and restoration of rivers. Here is summarised a review of modelling approaches that can help to investigate aspects of the interaction between plants and physical processes in river environments. The content is taken from section 3.4 of the Deliverable 2.2 (see also Solari et al. 2015).<br />
<br />
<br />
Models have been distinguished according to the following topics (Figure 1):<br />
(i) Effect of vegetation on hydromorphology. This includes the more complex models generally including advanced hydrology and sediment transport and simple vegetation which are mainly used for engineering purposes. It includes equations and process descriptions for flow resistance, bank erosion and bank accretion.<br />
<br />
(ii) Effect of hydromorphology on vegetation. This includes ecological models using hydromorphodynamics as environmental variables influencing plant survival, growth, reproduction and dispersal.<br />
<br />
(iii) Large wood. This includes models of breakage, transport and decomposition of large wood.<br />
<br />
(iv) Interaction between vegetation and hydromorphology. This includes several models explicitly including the interaction between vegetation and hydromorphology (topics i and ii combined).<br />
<br />
(v) Vegetation dynamics. This includes models that simulate interactions between plants and predict vegetation patterns in less disturbed environments (e.g. at higher altitudes on the floodplain) as a result of competition and facilitation processes.<br />
<br />
(vi) Interaction between groundwater and vegetation. This includes ecohydrological models with vegetation dynamics.<br />
<br />
[[File:VegHymoInteractions_models_Fig1.png|center|thumb|400px| Figure 1. Interaction between vegetation and hydromorphology.]]<br />
<br />
<br />
For each topic are listed:<br />
- the usability of the tools for the analysis of hydromorphological pressures and design of restoration measures;<br />
- future research and modelling challenges.<br />
<br />
==References==<br />
Solari L., Van Oorschot M., Belletti B., Hebdrix D., Rinaldi M., Vargas-Luna A. (2015). Advances on modelling riparian vegetation-hydromorphology interactions. River Research and Applications. DOI: 10.1002/rra.2910</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Category:Vegetation_ModelsCategory:Vegetation Models2015-06-30T14:37:02Z<p>Bbelletti: </p>
<hr />
<div>[[Category:Tools]]<br />
<br />
==Modelling Vegetation-Hydromorphology Interactions==<br />
<br />
Models can support river managers in the management, design and restoration of rivers. Here is summarised a review of modelling approaches that can help to investigate aspects of the interaction between plants and physical processes in river environments. The content is taken from section 3.4 of the Deliverable 2.2 (see also Solari et al. 2015).<br />
<br />
<br />
Models have been distinguished according to the following topics (Figure 1):<br />
(i) Effect of vegetation on hydromorphology. This includes the more complex models generally including advanced hydrology and sediment transport and simple vegetation which are mainly used for engineering purposes. It includes equations and process descriptions for flow resistance, bank erosion and bank accretion.<br />
<br />
(ii) Effect of hydromorphology on vegetation. This includes ecological models using hydromorphodynamics as environmental variables influencing plant survival, growth, reproduction and dispersal.<br />
<br />
(iii) Large wood. This includes models of breakage, transport and decomposition of large wood.<br />
<br />
(iv) Interaction between vegetation and hydromorphology. This includes several models explicitly including the interaction between vegetation and hydromorphology (topics i and ii combined).<br />
<br />
(v) Vegetation dynamics. This includes models that simulate interactions between plants and predict vegetation patterns in less disturbed environments (e.g. at higher altitudes on the floodplain) as a result of competition and facilitation processes.<br />
<br />
(vi) Interaction between groundwater and vegetation. This includes ecohydrological models with vegetation dynamics.<br />
<br />
[[File:VegHymoInteractions_models_Fig1.png|center|thumb|400px| Figure 1. Interaction between vegetation and hydromorphology.]]<br />
<br />
<br />
For each topic are listed:<br />
- the usability of the tools for the analysis of hydromorphological pressures and design of restoration measures;<br />
- future research and modelling challenges.<br />
<br />
<br />
==References==<br />
Solari L., Van Oorschot M., Belletti B., Hebdrix D., Rinaldi M., Vargas-Luna A. (2015). Advances on modelling riparian vegetation-hydromorphology interactions. River Research and Applications. DOI: 10.1002/rra.2910</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=File:VegHymoInteractions_models_Fig1.pngFile:VegHymoInteractions models Fig1.png2015-06-30T14:22:20Z<p>Bbelletti: </p>
<hr />
<div></div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Introduction_to_characterisation:_Multi-scale_Hierarchical_FrameworkIntroduction to characterisation: Multi-scale Hierarchical Framework2015-06-03T14:52:33Z<p>Bbelletti: /* How do river systems develop in time? */</p>
<hr />
<div>== Hydromorphological characterisation ==<br />
Effective river restoration calls for an understanding of how rivers work. A key step for this is hydromorphological characterization, looking at rivers from a perspective that discloses the relevant processes and forms. Hydromorphology is a matter of water and sediment, but also of vegetation interacting with water and sediment. This makes both geomorphological and ecological processes relevant.<br />
<br />
River management often focuses on individual reaches of river networks. However, the character and dynamism of river reaches depends not only upon natural processes and human interventions within the reach, but also within the catchment, particularly upstream of the reach (see Figure 1). The character of river reaches often responds to processes and interventions across the catchment in a delayed way as changes in processes propagate from their source areas through the river network to individual reaches.<br />
<br />
A river is a connected ecosystem generated by hydrological, geomorphological and ecological processes that interact at many temporal and spatial scales. Hydromorphological characterization aims at capturing and explaining this complexity (see [[:Category:River_Characterisation]]). This is the key step in developing a fuller understanding of how a river functions physically, as a foundation for evaluating river conditions and developing a programme of restoration measures.<br />
<br />
The spatial organization of rivers and the way how such spatial organization evolves through time create the variety of forms and processes we observe in nature. This builds the theoretical framework (see [[:Category:River_Characterisation#Multi-scale_Hierarchical_Framework|Multi-scale_Hierarchical_Framework]]) for characterizing relevant spatial and temporal scales at which key fluvial processes occur.<br />
<br />
== How are river systems organized in space? ==<br />
<br />
When thinking about a river, we usually imagine a reach of a few kilometres in length. This is the key spatial scale within a framework of spatial components of the river landscape (see Figure 1). For characterizing the full complexity of rivers, however, it is useful to consider components larger and smaller than a reach too. A hierarchical framework for this helps in adopting the relevant spatial scales to describe specific river system characteristics (see [[:Category:River_Characterisation#The_Framework|The_Framework]]).<br />
<br />
[[File:RiverCharacterisation_Figure1_last.png|center|thumb|600px| Figure 1. The spatial units and scales of the REFORM hierachical framework (Photo credits: Google Earth; University of Florence; F. Comiti (Free University of Bozen))]]<br />
<br />
The hierarchical framework proposes eight different sizes of spatial unit (see [[:Category:River_Characterisation#Hierarchy_of_spatial_units|Hierarchy_of_spatial_units]]) to investigate different river features. Seven of them are represented in Figure 1. The catchment unit encloses the land that is drained by a river and its tributaries, for which the area is typically 10<sup>2</sup>-10<sup>5</sup> km<sup>2</sup>. Landscape units are portions of the catchment that show different forms of physical landscape that can be summarised by properties such as land surface elevation, land steepness, and valley density. They have a typical area of 10<sup>2</sup>-10<sup>3</sup> km<sup>2</sup>. The segment unit is a section of the river system that is located within a valley of sufficiently uniform gradient and width, so that the river is confined by its valley to a similar degree and has similar energy through the segment. River segments are typically 10<sup>1</sup>-10<sup>2</sup> km long.<br />
<br />
The reach unit is a section of the river network in which not only the valley and flow energy are relatively uniform, but also other conditions, such as bed sediments, bank properties and riparian vegetation. This uniformity in conditions gives the river reach a consistent appearance through its length as a result of a near-consistent internal set of process-form interactions. A reach unit is typically 10<sup>-1</sup>-10<sup>1</sup> km in length, and a river segment can contain one to several reaches.<br />
<br />
A geomorphic unit is a portion of a reach that contains a landform created by erosion or deposition of sediment, sometimes in association with vegetation, with a typical length of 10<sup>0</sup>-10<sup>2</sup> m. Geomorphic units can be located within the channel (bed and mid-channel features), along the channel edges (marginal and bank features) or on the floodplain. A hydraulic unit is a spatially distinct patch of relatively homogeneous surface flow and substrate character with a typical size of 10<sup>-1</sup>-10<sup>1</sup> m. A single geomorphic unit can include one to several hydraulic units. River elements include individuals and patches of sediment particles, plants, and wood (10<sup>-2</sup>-10<sup>-1</sup> km). The framework is hierarchical in that each of the spatial units nests within one another so that their boundaries do not overlap.<br />
<br />
Each unit represents a particular spatial scale that is suited to investigating specific processes, human pressures and forms that eventually impact on the character and dynamics of river reach units (see [[:Category:River_Characterisation#Four_stages_of_river_characterization|Four_stages_of_river_characterization]]: [[:Category:River_Characterisation#Stage_1:_Delineation_of_spatial_units|Stage_1_(Delineation_of_spatial_units)]] and [[:Category:River_Characterisation#Stage_2:_Characterisation_of_current_and_past_condition|Stage_2_(Characterising_current_condition)]]).<br />
<br />
Figure 2 lists some examples of indicators of processes, human pressures and forms which can be calculated for each spatial unit (see [[:Category:River_Characterisation#Stage_3:_Indicators|Stage_3:_Indicators]]).<br />
<br />
[[File:RiverCharacterisation_Figure2_last.png|center|thumb|600px| Figure 2. Examples of relevant indicators of processes, human pressures and forms for each spatial unit (Photo credits: Google Earth; University of Florence; F. Comiti (Free University of Bozen))]]<br />
<br />
At the catchment scale, for example, it is relevant to monitor land cover type because it affects run-off production. At the landscape unit scale, potential sources of sediment (for instance gullies, landslides) can be located to estimate the likely supply of such sediment to smaller units. The segment scale is suitable to investigate physical pressures altering longitudinal connectivity, riparian corridor features, valley features and river flow regimes. All of these can be assumed to be fairly homogenous at this scale and thus well-represented by summary indicators. At the reach scale, indicators summarising channel dimensions and type, bank and bed sediments, and riparian properties can be represented by informative indicators. Within reach units, geomorphic units such as riffles, bars or islands can be identified and at a finer scale specific hydraulic units and river elements can be surveyed.<br />
<br />
It is at the reach scale that the many features found across floodplains and river channels adjust to the cascade of influences that propagate to the reach from larger spatial units and scales. This is also the scale that is affected by interactions and feedbacks within the reach among fluvial processes, geomorphic units, hydraulic units, and smaller river elements such as sediment particles, logs, and plants.<br />
<br />
== How do river systems develop in time? ==<br />
<br />
The temporal dimension is necessary for a complete characterization of river processes. This adds knowledge about the changes in features and indicators through time within each spatial unit, and so discloses information that helps to explain how changes occur at different spatial scales and dynamically interact between scales (see [[:Category:River_Characterisation#Characterising_past_condition_and_quantifying_rates_of_processes|Stage_2:_Characterising_past_condition]]). The historical evolution of hydromorphological features and human interventions may be quite different among catchments and may influence river forms and processes in different ways in different catchment environments. Thus, the identification of possible changes in controlling variables forms a basis for the assessment of current and past conditions, as well as for the prediction of future scenarios. Changes through time can be investigated in their historical context, for instance over the last century for changes at catchment to reach scales. A resolution of about 10 to 20 years is suited to the reach scale and below (Figure 3). Proper characterization of historical and contemporary changes at the relevant spatial scales is essential for diagnosing river problems and designing sustainable restoration measures.<br />
<br />
[[File:RiverCharacterisation_Figure3_last.png|center|thumb|600px| Figure 3. Example of the temporal dimension within spatial units, scales, processes and indicators (Photo credits: Google Earth; Archivio Cartografico Provincia di La Spezia, Italy; Istituto Geografico Militare, Italy; University of Florence; P. Vezza (Politecnico di Torino, Italy))]]<br />
<br />
Figure 3 illustrates the changing processes monitored and their temporal scale for each spatial unit in an example catchment. Land cover change over more than 50 years is shown at the catchment scale. Significant land cover and management alterations have occurred over this period throughout Europe, and have affected runoff production and consequently the entire cascade of river processes that drive river hydromorphology and features within the catchment. At the landscape unit scale, afforestation of a valley is illustrated. Extension of forest land cover stabilizes hill slopes and decreases runoff production, leading to a reduction in soil erosion and the supply of sediment to river channel. Such changes in the delivery of water and sediment lead to changes in the size and the form of a river. Sometimes even the type of river is changed. The segment scale illustrates an increase over the last century in infrastructure that directly impacts the river and it processes. Dams disconnect the down-river movement of sediment, often leading to a sediment deficit downstream the dam and degradation of the river bed. Bank protection limits lateral movement of the river and its capacity to erode bank sediment.<br />
<br />
The effects of the installation of river infrastructures that decrease sediment supply and constrain river channel movements are most clearly seen at the reach scale. In the example river reach, a river that was multi-thread braided in the 1950s has been transformed into a single-thread sinuous river accompanied by a severe reduction in the width of the active channel. Changes are also observed in the geomorphic units, with encroachment of vegetation incorporating an island into the floodplain within a period of ten years. At the hydraulic unit scale, the example illustrates the impact of changes in river stage on unit character, even when the river channel form has not changed. At the river element scale, the example shows significant changes in the type and distribution of elements present as the result of a single flood, which has redistributed them within and between river reaches.<br />
<br />
The integration of spatial characteristics and their changes through time allows the investigator to identify which spatial units and temporal scales drive the relevant forms and processes. The hierarchical framework provides an integrated and scientifically sound basis for diagnosing causes and effects of the hydromorphological process cascade (see [[:Category:River_Characterisation#Stage_4:_Interpreting_condition,_trajectories_of_change,_and_sensitivity|Stage_4]]). This process-based characterization is suitable to support river restoration from basin-scale planning to the implementation of local projects.<br />
<br />
== Additional information ==<br />
More details on river hydromorphological characterisation can be found in the [[media: Deliverable2_1.pdf | REFORM Deliverable 2.1]] and the REFORM Deliverable 6.2.</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Introduction_to_characterisation:_Multi-scale_Hierarchical_FrameworkIntroduction to characterisation: Multi-scale Hierarchical Framework2015-06-03T14:44:49Z<p>Bbelletti: /* How are river systems organized in space? */</p>
<hr />
<div>== Hydromorphological characterisation ==<br />
Effective river restoration calls for an understanding of how rivers work. A key step for this is hydromorphological characterization, looking at rivers from a perspective that discloses the relevant processes and forms. Hydromorphology is a matter of water and sediment, but also of vegetation interacting with water and sediment. This makes both geomorphological and ecological processes relevant.<br />
<br />
River management often focuses on individual reaches of river networks. However, the character and dynamism of river reaches depends not only upon natural processes and human interventions within the reach, but also within the catchment, particularly upstream of the reach (see Figure 1). The character of river reaches often responds to processes and interventions across the catchment in a delayed way as changes in processes propagate from their source areas through the river network to individual reaches.<br />
<br />
A river is a connected ecosystem generated by hydrological, geomorphological and ecological processes that interact at many temporal and spatial scales. Hydromorphological characterization aims at capturing and explaining this complexity (see [[:Category:River_Characterisation]]). This is the key step in developing a fuller understanding of how a river functions physically, as a foundation for evaluating river conditions and developing a programme of restoration measures.<br />
<br />
The spatial organization of rivers and the way how such spatial organization evolves through time create the variety of forms and processes we observe in nature. This builds the theoretical framework (see [[:Category:River_Characterisation#Multi-scale_Hierarchical_Framework|Multi-scale_Hierarchical_Framework]]) for characterizing relevant spatial and temporal scales at which key fluvial processes occur.<br />
<br />
== How are river systems organized in space? ==<br />
<br />
When thinking about a river, we usually imagine a reach of a few kilometres in length. This is the key spatial scale within a framework of spatial components of the river landscape (see Figure 1). For characterizing the full complexity of rivers, however, it is useful to consider components larger and smaller than a reach too. A hierarchical framework for this helps in adopting the relevant spatial scales to describe specific river system characteristics (see [[:Category:River_Characterisation#The_Framework|The_Framework]]).<br />
<br />
[[File:RiverCharacterisation_Figure1_last.png|center|thumb|600px| Figure 1. The spatial units and scales of the REFORM hierachical framework (Photo credits: Google Earth; University of Florence; F. Comiti (Free University of Bozen))]]<br />
<br />
The hierarchical framework proposes eight different sizes of spatial unit (see [[:Category:River_Characterisation#Hierarchy_of_spatial_units|Hierarchy_of_spatial_units]]) to investigate different river features. Seven of them are represented in Figure 1. The catchment unit encloses the land that is drained by a river and its tributaries, for which the area is typically 10<sup>2</sup>-10<sup>5</sup> km<sup>2</sup>. Landscape units are portions of the catchment that show different forms of physical landscape that can be summarised by properties such as land surface elevation, land steepness, and valley density. They have a typical area of 10<sup>2</sup>-10<sup>3</sup> km<sup>2</sup>. The segment unit is a section of the river system that is located within a valley of sufficiently uniform gradient and width, so that the river is confined by its valley to a similar degree and has similar energy through the segment. River segments are typically 10<sup>1</sup>-10<sup>2</sup> km long.<br />
<br />
The reach unit is a section of the river network in which not only the valley and flow energy are relatively uniform, but also other conditions, such as bed sediments, bank properties and riparian vegetation. This uniformity in conditions gives the river reach a consistent appearance through its length as a result of a near-consistent internal set of process-form interactions. A reach unit is typically 10<sup>-1</sup>-10<sup>1</sup> km in length, and a river segment can contain one to several reaches.<br />
<br />
A geomorphic unit is a portion of a reach that contains a landform created by erosion or deposition of sediment, sometimes in association with vegetation, with a typical length of 10<sup>0</sup>-10<sup>2</sup> m. Geomorphic units can be located within the channel (bed and mid-channel features), along the channel edges (marginal and bank features) or on the floodplain. A hydraulic unit is a spatially distinct patch of relatively homogeneous surface flow and substrate character with a typical size of 10<sup>-1</sup>-10<sup>1</sup> m. A single geomorphic unit can include one to several hydraulic units. River elements include individuals and patches of sediment particles, plants, and wood (10<sup>-2</sup>-10<sup>-1</sup> km). The framework is hierarchical in that each of the spatial units nests within one another so that their boundaries do not overlap.<br />
<br />
Each unit represents a particular spatial scale that is suited to investigating specific processes, human pressures and forms that eventually impact on the character and dynamics of river reach units (see [[:Category:River_Characterisation#Four_stages_of_river_characterization|Four_stages_of_river_characterization]]: [[:Category:River_Characterisation#Stage_1:_Delineation_of_spatial_units|Stage_1_(Delineation_of_spatial_units)]] and [[:Category:River_Characterisation#Stage_2:_Characterisation_of_current_and_past_condition|Stage_2_(Characterising_current_condition)]]).<br />
<br />
Figure 2 lists some examples of indicators of processes, human pressures and forms which can be calculated for each spatial unit (see [[:Category:River_Characterisation#Stage_3:_Indicators|Stage_3:_Indicators]]).<br />
<br />
[[File:RiverCharacterisation_Figure2_last.png|center|thumb|600px| Figure 2. Examples of relevant indicators of processes, human pressures and forms for each spatial unit (Photo credits: Google Earth; University of Florence; F. Comiti (Free University of Bozen))]]<br />
<br />
At the catchment scale, for example, it is relevant to monitor land cover type because it affects run-off production. At the landscape unit scale, potential sources of sediment (for instance gullies, landslides) can be located to estimate the likely supply of such sediment to smaller units. The segment scale is suitable to investigate physical pressures altering longitudinal connectivity, riparian corridor features, valley features and river flow regimes. All of these can be assumed to be fairly homogenous at this scale and thus well-represented by summary indicators. At the reach scale, indicators summarising channel dimensions and type, bank and bed sediments, and riparian properties can be represented by informative indicators. Within reach units, geomorphic units such as riffles, bars or islands can be identified and at a finer scale specific hydraulic units and river elements can be surveyed.<br />
<br />
It is at the reach scale that the many features found across floodplains and river channels adjust to the cascade of influences that propagate to the reach from larger spatial units and scales. This is also the scale that is affected by interactions and feedbacks within the reach among fluvial processes, geomorphic units, hydraulic units, and smaller river elements such as sediment particles, logs, and plants.<br />
<br />
== How do river systems develop in time? ==<br />
<br />
The temporal dimension is necessary for a complete characterization of river processes. This adds knowledge about the changes in features and indicators through time within each spatial unit, and so discloses information that helps to explain how changes occur at different spatial scales and dynamically interact between scales (see [[:Category:River_Characterisation#Characterising_past_condition_and_quantifying_rates_of_processes|Stage_2:_Characterising_past_condition]]). The historical evolution of hydromorphological features and human interventions may be quite different among catchments and may influence river forms and processes in different ways in different catchment environments. Thus, the identification of possible changes in controlling variables forms a basis for the assessment of current and past conditions, as well as for the prediction of future scenarios. Changes through time can be investigated in their historical context, for instance over the last century for changes at catchment to reach scales. A resolution of about 10 to 20 years is suited to the reach scale and below (Figure 3). Proper characterization of historical and contemporary changes at the relevant spatial scales is essential for diagnosing river problems and designing sustainable restoration measures.<br />
<br />
[[File:RiverCharacterisation_Figure3_last.png|center|thumb|600px| Figure 3. Example of the temporal dimension within spatial units, scales, processes and indicators (Photo credits: Google Earth; Archivio Cartografico Provincia di La Spezia, Italy; Istituto Geografico Militare, Italy; University of Florence; P. Vezza (Politecnico di Torino, Italy))]]<br />
<br />
Figure 3 illustrates the changing processes monitored and their temporal scale for each spatial unit in an example catchment. Land cover change over more than 50 years is shown at the catchment scale. Significant land cover and management alterations have occurred over this period throughout Europe, and have affected runoff production and consequently the entire cascade of river processes that drive river hydromorphology and features within the catchment. At the landscape unit scale, afforestation of a valley is illustrated. Extension of forest land cover stabilizes hill slopes and decreases runoff production, leading to a reduction in soil erosion and the supply of sediment to river channel. Such changes in the delivery of water and sediment lead to changes in the size and the form of a river. Sometimes even the type of river is changed. The segment scale illustrates an increase over the last century in infrastructure that directly impacts the river and it processes. Dams disconnect the down-river movement of sediment, often leading to a sediment deficit downstream the dam and degradation of the river bed. Bank protection limits lateral movement of the river and its capacity to erode bank sediment.<br />
<br />
The effects of the installation of river infrastructures that decrease sediment supply and constrain river channel movements are most clearly seen at the reach scale. In the example river reach, a river that was multi-thread braided in the 1950s has been transformed into a single-thread sinuous river accompanied by a severe reduction in the width of the active channel. Changes are also observed in the geomorphic units, with encroachment of vegetation incorporating an island into the floodplain within a period of ten years. At the hydraulic unit scale, the example illustrates the impact of changes in river stage on unit character, even when the river channel form has not changed. At the river element scale, the example shows significant changes in the type and distribution of elements present as the result of a single flood, which has redistributed them within and between river reaches.<br />
<br />
The integration of spatial characteristics and their changes through time allows the investigator to identify which spatial units and temporal scales drive the relevant forms and processes. The hierarchical framework provides an integrated and scientifically sound basis for diagnosing causes and effects of the hydromorphological process cascade (see [[:Category:River_Characterisation#Stage_4:_Interpreting_condition,_trajectories_of_change,_and_sensitivity|Stage_4]]). This process-based characterization is suitable to support river restoration from basin-scale planning to the implementation of local projects.</div>Bbellettihttps://wiki.reformrivers.eu/index.php?title=Introduction_to_characterisation:_Multi-scale_Hierarchical_FrameworkIntroduction to characterisation: Multi-scale Hierarchical Framework2015-06-03T14:41:43Z<p>Bbelletti: /* How are river systems organized in space? */</p>
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<div>== Hydromorphological characterisation ==<br />
Effective river restoration calls for an understanding of how rivers work. A key step for this is hydromorphological characterization, looking at rivers from a perspective that discloses the relevant processes and forms. Hydromorphology is a matter of water and sediment, but also of vegetation interacting with water and sediment. This makes both geomorphological and ecological processes relevant.<br />
<br />
River management often focuses on individual reaches of river networks. However, the character and dynamism of river reaches depends not only upon natural processes and human interventions within the reach, but also within the catchment, particularly upstream of the reach (see Figure 1). The character of river reaches often responds to processes and interventions across the catchment in a delayed way as changes in processes propagate from their source areas through the river network to individual reaches.<br />
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A river is a connected ecosystem generated by hydrological, geomorphological and ecological processes that interact at many temporal and spatial scales. Hydromorphological characterization aims at capturing and explaining this complexity (see [[:Category:River_Characterisation]]). This is the key step in developing a fuller understanding of how a river functions physically, as a foundation for evaluating river conditions and developing a programme of restoration measures.<br />
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The spatial organization of rivers and the way how such spatial organization evolves through time create the variety of forms and processes we observe in nature. This builds the theoretical framework (see [[:Category:River_Characterisation#Multi-scale_Hierarchical_Framework|Multi-scale_Hierarchical_Framework]]) for characterizing relevant spatial and temporal scales at which key fluvial processes occur.<br />
<br />
== How are river systems organized in space? ==<br />
<br />
When thinking about a river, we usually imagine a reach of a few kilometres in length. This is the key spatial scale within a framework of spatial components of the river landscape (see Figure 1). For characterizing the full complexity of rivers, however, it is useful to consider components larger and smaller than a reach too. A hierarchical framework for this helps in adopting the relevant spatial scales to describe specific river system characteristics (see [[:Category:River_Characterisation#The_Framework|The_Framework]]).<br />
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[[File:RiverCharacterisation_Figure1_last.png|center|thumb|600px| Figure 1. The spatial units and scales of the REFORM hierachical framework (Photo credits: Google Earth; University of Florence; F. Comiti (Free University of Bozen))]]<br />
<br />
The hierarchical framework proposes eight different sizes of spatial unit (see [[:Category:River_Characterisation#Hierarchy_of_spatial_units|Hierarchy_of_spatial_units]]) to investigate different river features. Seven of them are represented in Figure 1. The catchment unit encloses the land that is drained by a river and its tributaries, for which the area is typically 10<sup>2</sup>-10<sup>5</sup> km<sup>2</sup>. Landscape units are portions of the catchment that show different forms of physical landscape that can be summarised by properties such as land surface elevation, land steepness, and valley density. They have a typical area of 10<sup>2</sup>-10<sup>3</sup> km<sup>2</sup>. The segment unit is a section of the river system that is located within a valley of sufficiently uniform gradient and width, so that the river is confined by its valley to a similar degree and has similar energy through the segment. River segments are typically 10<sup>1</sup>-10<sup>2</sup> km long.<br />
<br />
The reach unit is a section of the river network in which not only the valley and flow energy are relatively uniform, but also other conditions, such as bed sediments, bank properties and riparian vegetation. This uniformity in conditions gives the river reach a consistent appearance through its length as a result of a near-consistent internal set of process-form interactions. A reach unit is typically 10<sup>-1</sup>-10<sup>1</sup> km in length, and a river segment can contain one to several reaches.<br />
<br />
A geomorphic unit is a portion of a reach that contains a landform created by erosion or deposition of sediment, sometimes in association with vegetation, with a typical length of 10<sup>0</sup>-10<sup>2</sup> m. Geomorphic units can be located within the channel (bed and mid-channel features), along the channel edges (marginal and bank features) or on the floodplain. A hydraulic unit is a spatially distinct patch of relatively homogeneous surface flow and substrate character with a typical size of 10<sup>-1</sup>-10<sup>1</sup> m. A single geomorphic unit can include one to several hydraulic units. River elements include individuals and patches of sediment particles, plants, and wood (10<sup>-2</sup>-10<sup>-1</sup> km). The framework is hierarchical in that each of the spatial units nests within one another so that their boundaries do not overlap.<br />
<br />
Each unit represents a particular spatial scale that is suited to investigating specific processes, human pressures and forms that eventually impact on the character and dynamics of river reach units (see [[:Category:River_Characterisation#Four_stages_of_river_characterization|Four_stages_of_river_characterization]]: [[:Category:River_Characterisation#Stage_1:_Delineation_of_spatial_units|Stage_1,_Delineation_of_spatial_units]]; [[:Category:River_Characterisation#Stage_2:_Characterisation_of_current_and_past_condition|Stage_2,_Characterising_current_condition]]).<br />
<br />
Figure 2 lists some examples of indicators of processes, human pressures and forms which can be calculated for each spatial unit (see [[:Category:River_Characterisation#Stage_3:_Indicators|Stage_3:_Indicators]]).<br />
<br />
[[File:RiverCharacterisation_Figure2_last.png|center|thumb|600px| Figure 2. Examples of relevant indicators of processes, human pressures and forms for each spatial unit (Photo credits: Google Earth; University of Florence; F. Comiti (Free University of Bozen))]]<br />
<br />
At the catchment scale, for example, it is relevant to monitor land cover type because it affects run-off production. At the landscape unit scale, potential sources of sediment (for instance gullies, landslides) can be located to estimate the likely supply of such sediment to smaller units. The segment scale is suitable to investigate physical pressures altering longitudinal connectivity, riparian corridor features, valley features and river flow regimes. All of these can be assumed to be fairly homogenous at this scale and thus well-represented by summary indicators. At the reach scale, indicators summarising channel dimensions and type, bank and bed sediments, and riparian properties can be represented by informative indicators. Within reach units, geomorphic units such as riffles, bars or islands can be identified and at a finer scale specific hydraulic units and river elements can be surveyed.<br />
<br />
It is at the reach scale that the many features found across floodplains and river channels adjust to the cascade of influences that propagate to the reach from larger spatial units and scales. This is also the scale that is affected by interactions and feedbacks within the reach among fluvial processes, geomorphic units, hydraulic units, and smaller river elements such as sediment particles, logs, and plants.<br />
<br />
== How do river systems develop in time? ==<br />
<br />
The temporal dimension is necessary for a complete characterization of river processes. This adds knowledge about the changes in features and indicators through time within each spatial unit, and so discloses information that helps to explain how changes occur at different spatial scales and dynamically interact between scales (see [[:Category:River_Characterisation#Characterising_past_condition_and_quantifying_rates_of_processes|Stage_2:_Characterising_past_condition]]). The historical evolution of hydromorphological features and human interventions may be quite different among catchments and may influence river forms and processes in different ways in different catchment environments. Thus, the identification of possible changes in controlling variables forms a basis for the assessment of current and past conditions, as well as for the prediction of future scenarios. Changes through time can be investigated in their historical context, for instance over the last century for changes at catchment to reach scales. A resolution of about 10 to 20 years is suited to the reach scale and below (Figure 3). Proper characterization of historical and contemporary changes at the relevant spatial scales is essential for diagnosing river problems and designing sustainable restoration measures.<br />
<br />
[[File:RiverCharacterisation_Figure3_last.png|center|thumb|600px| Figure 3. Example of the temporal dimension within spatial units, scales, processes and indicators (Photo credits: Google Earth; Archivio Cartografico Provincia di La Spezia, Italy; Istituto Geografico Militare, Italy; University of Florence; P. Vezza (Politecnico di Torino, Italy))]]<br />
<br />
Figure 3 illustrates the changing processes monitored and their temporal scale for each spatial unit in an example catchment. Land cover change over more than 50 years is shown at the catchment scale. Significant land cover and management alterations have occurred over this period throughout Europe, and have affected runoff production and consequently the entire cascade of river processes that drive river hydromorphology and features within the catchment. At the landscape unit scale, afforestation of a valley is illustrated. Extension of forest land cover stabilizes hill slopes and decreases runoff production, leading to a reduction in soil erosion and the supply of sediment to river channel. Such changes in the delivery of water and sediment lead to changes in the size and the form of a river. Sometimes even the type of river is changed. The segment scale illustrates an increase over the last century in infrastructure that directly impacts the river and it processes. Dams disconnect the down-river movement of sediment, often leading to a sediment deficit downstream the dam and degradation of the river bed. Bank protection limits lateral movement of the river and its capacity to erode bank sediment.<br />
<br />
The effects of the installation of river infrastructures that decrease sediment supply and constrain river channel movements are most clearly seen at the reach scale. In the example river reach, a river that was multi-thread braided in the 1950s has been transformed into a single-thread sinuous river accompanied by a severe reduction in the width of the active channel. Changes are also observed in the geomorphic units, with encroachment of vegetation incorporating an island into the floodplain within a period of ten years. At the hydraulic unit scale, the example illustrates the impact of changes in river stage on unit character, even when the river channel form has not changed. At the river element scale, the example shows significant changes in the type and distribution of elements present as the result of a single flood, which has redistributed them within and between river reaches.<br />
<br />
The integration of spatial characteristics and their changes through time allows the investigator to identify which spatial units and temporal scales drive the relevant forms and processes. The hierarchical framework provides an integrated and scientifically sound basis for diagnosing causes and effects of the hydromorphological process cascade (see [[:Category:River_Characterisation#Stage_4:_Interpreting_condition,_trajectories_of_change,_and_sensitivity|Stage_4]]). This process-based characterization is suitable to support river restoration from basin-scale planning to the implementation of local projects.</div>Bbelletti