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A Modelling Framework to Assess the Effect of Pressures on River Abiotic Habitat Conditions and Biota.

Kail J, Guse B, Radinger J, Schröder M, Kiesel J, Kleinhans M, Schuurman F, Fohrer N, Hering D, Wolter C - PLoS ONE (2015)

Bottom Line: Moreover, these approaches do not consider long-term morphological changes that affect habitat conditions.Technically, it was possible to link the different models, but future applications would benefit from the development of open source software for all modelling steps to enable fully automated model runs.The modelling framework is flexible and allows for including additional models and investigating different research and management questions, e.g., in climate impact research as well as river restoration and management.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology and Ecology of Fishes, Leibniz-Institute for Freshwater Ecology and Inland Fisheries, Berlin, Germany; Department of Aquatic Ecology, University of Duisburg-Essen, Essen, Germany.

ABSTRACT
River biota are affected by global reach-scale pressures, but most approaches for predicting biota of rivers focus on river reach or segment scale processes and habitats. Moreover, these approaches do not consider long-term morphological changes that affect habitat conditions. In this study, a modelling framework was further developed and tested to assess the effect of pressures at different spatial scales on reach-scale habitat conditions and biota. Ecohydrological and 1D hydrodynamic models were used to predict discharge and water quality at the catchment scale and the resulting water level at the downstream end of a study reach. Long-term reach morphology was modelled using empirical regime equations, meander migration and 2D morphodynamic models. The respective flow and substrate conditions in the study reach were predicted using a 2D hydrodynamic model, and the suitability of these habitats was assessed with novel habitat models. In addition, dispersal models for fish and macroinvertebrates were developed to assess the re-colonization potential and to finally compare habitat suitability and the availability/ability of species to colonize these habitats. Applicability was tested and model performance was assessed by comparing observed and predicted conditions in the lowland Treene River in northern Germany. Technically, it was possible to link the different models, but future applications would benefit from the development of open source software for all modelling steps to enable fully automated model runs. Future research needs concern the physical modelling of long-term morphodynamics, feedback of biota (e.g., macrophytes) on abiotic habitat conditions, species interactions, and empirical data on the hydraulic habitat suitability and dispersal abilities of macroinvertebrates. The modelling framework is flexible and allows for including additional models and investigating different research and management questions, e.g., in climate impact research as well as river restoration and management.

No MeSH data available.


Comparison of the relative abundance of macroinvertebrates and the re-colonization potential.Relative abundance = modelled abundance for present substrate conditions related to abundance for a range of natural substrate conditions (median and range are given). Re-colonization potential = percentage of river network that is reachable (a range of conservative and progressive scenarios are given). Br Brachycentrus subnubilus, Ca Calopteryx splendens, Ep Ephemera danica, Ka Kageronia fuscogrisea, Or Orectochilus villosus Lv., Pa Paraleptophlebia submarginata, He Hetpagenia sp.).
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pone.0130228.g006: Comparison of the relative abundance of macroinvertebrates and the re-colonization potential.Relative abundance = modelled abundance for present substrate conditions related to abundance for a range of natural substrate conditions (median and range are given). Re-colonization potential = percentage of river network that is reachable (a range of conservative and progressive scenarios are given). Br Brachycentrus subnubilus, Ca Calopteryx splendens, Ep Ephemera danica, Ka Kageronia fuscogrisea, Or Orectochilus villosus Lv., Pa Paraleptophlebia submarginata, He Hetpagenia sp.).

Mentions: For macroinvertebrates, the habitat suitability of the present substrate conditions in the study reach (baseline scenario) did substantially differ between the macroinvertebrate species (the x-axis in Fig 6). For most model species, the present substrate conditions in the study reach were equally well suited as the natural reference substrate conditions. For these species, the modelled abundance values for the present state were similar to the reference values with a median relative abundance of 98–102%. However, organic substrates and gravel would be more abundant in the natural state, and hence, the modelled abundance values of all species mainly occurring on these substrates were much lower in the baseline scenario and only reached 33–74% of the median abundances predicted for the natural reference conditions. In contrast to fish, the macroinvertebrate model species did not differ much in respect to their re-colonization potential (the y-axis in Fig 6), and the share of the river network that was reachable only ranged from 26–45%.


A Modelling Framework to Assess the Effect of Pressures on River Abiotic Habitat Conditions and Biota.

Kail J, Guse B, Radinger J, Schröder M, Kiesel J, Kleinhans M, Schuurman F, Fohrer N, Hering D, Wolter C - PLoS ONE (2015)

Comparison of the relative abundance of macroinvertebrates and the re-colonization potential.Relative abundance = modelled abundance for present substrate conditions related to abundance for a range of natural substrate conditions (median and range are given). Re-colonization potential = percentage of river network that is reachable (a range of conservative and progressive scenarios are given). Br Brachycentrus subnubilus, Ca Calopteryx splendens, Ep Ephemera danica, Ka Kageronia fuscogrisea, Or Orectochilus villosus Lv., Pa Paraleptophlebia submarginata, He Hetpagenia sp.).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4482704&req=5

pone.0130228.g006: Comparison of the relative abundance of macroinvertebrates and the re-colonization potential.Relative abundance = modelled abundance for present substrate conditions related to abundance for a range of natural substrate conditions (median and range are given). Re-colonization potential = percentage of river network that is reachable (a range of conservative and progressive scenarios are given). Br Brachycentrus subnubilus, Ca Calopteryx splendens, Ep Ephemera danica, Ka Kageronia fuscogrisea, Or Orectochilus villosus Lv., Pa Paraleptophlebia submarginata, He Hetpagenia sp.).
Mentions: For macroinvertebrates, the habitat suitability of the present substrate conditions in the study reach (baseline scenario) did substantially differ between the macroinvertebrate species (the x-axis in Fig 6). For most model species, the present substrate conditions in the study reach were equally well suited as the natural reference substrate conditions. For these species, the modelled abundance values for the present state were similar to the reference values with a median relative abundance of 98–102%. However, organic substrates and gravel would be more abundant in the natural state, and hence, the modelled abundance values of all species mainly occurring on these substrates were much lower in the baseline scenario and only reached 33–74% of the median abundances predicted for the natural reference conditions. In contrast to fish, the macroinvertebrate model species did not differ much in respect to their re-colonization potential (the y-axis in Fig 6), and the share of the river network that was reachable only ranged from 26–45%.

Bottom Line: Moreover, these approaches do not consider long-term morphological changes that affect habitat conditions.Technically, it was possible to link the different models, but future applications would benefit from the development of open source software for all modelling steps to enable fully automated model runs.The modelling framework is flexible and allows for including additional models and investigating different research and management questions, e.g., in climate impact research as well as river restoration and management.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology and Ecology of Fishes, Leibniz-Institute for Freshwater Ecology and Inland Fisheries, Berlin, Germany; Department of Aquatic Ecology, University of Duisburg-Essen, Essen, Germany.

ABSTRACT
River biota are affected by global reach-scale pressures, but most approaches for predicting biota of rivers focus on river reach or segment scale processes and habitats. Moreover, these approaches do not consider long-term morphological changes that affect habitat conditions. In this study, a modelling framework was further developed and tested to assess the effect of pressures at different spatial scales on reach-scale habitat conditions and biota. Ecohydrological and 1D hydrodynamic models were used to predict discharge and water quality at the catchment scale and the resulting water level at the downstream end of a study reach. Long-term reach morphology was modelled using empirical regime equations, meander migration and 2D morphodynamic models. The respective flow and substrate conditions in the study reach were predicted using a 2D hydrodynamic model, and the suitability of these habitats was assessed with novel habitat models. In addition, dispersal models for fish and macroinvertebrates were developed to assess the re-colonization potential and to finally compare habitat suitability and the availability/ability of species to colonize these habitats. Applicability was tested and model performance was assessed by comparing observed and predicted conditions in the lowland Treene River in northern Germany. Technically, it was possible to link the different models, but future applications would benefit from the development of open source software for all modelling steps to enable fully automated model runs. Future research needs concern the physical modelling of long-term morphodynamics, feedback of biota (e.g., macrophytes) on abiotic habitat conditions, species interactions, and empirical data on the hydraulic habitat suitability and dispersal abilities of macroinvertebrates. The modelling framework is flexible and allows for including additional models and investigating different research and management questions, e.g., in climate impact research as well as river restoration and management.

No MeSH data available.