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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.


Exemplary results from the application of the modelling framework in the Treene River.The consecutive modelling steps from the ecohydrological model to the habitat models are shown. *Mapped substrate composition was used to illustrate the application of the Habitat Evaluation Tool (HET). Sediment transport was not modelled because mobile bed-substrate was purely sand, and hence, any sorting would result in no change in the HET output.
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pone.0130228.g004: Exemplary results from the application of the modelling framework in the Treene River.The consecutive modelling steps from the ecohydrological model to the habitat models are shown. *Mapped substrate composition was used to illustrate the application of the Habitat Evaluation Tool (HET). Sediment transport was not modelled because mobile bed-substrate was purely sand, and hence, any sorting would result in no change in the HET output.

Mentions: The performance of the ecohydrological SWAT model was good for discharge (a Nash-Sutcliffe efficiency index of 0.65 to 0.82 in the calibration and 0.58 to 0.80 in the validation period), satisfying for nitrate (0.62 in the calibration, 0.74 in the validation) and total phosphorus (0.56 and 0.37), but low for fine sediment loads (0.46 and 0.10). A more detailed temporal analysis of parameter sensitivity and model performance showed that the model results were especially sensitive to groundwater parameters, indicating that the groundwater module has the highest potential for improvement. Furthermore, model performance was highest for peak discharges and the recession phase and lower for long dry periods and the resaturation phase [75], i.e., at low discharges, which are of special importance for biota. The mean monthly values of the 100 STAR runs were used in the subsequent modelling steps (monthly Q50 values exemplarily shown in Fig 4M1).


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)

Exemplary results from the application of the modelling framework in the Treene River.The consecutive modelling steps from the ecohydrological model to the habitat models are shown. *Mapped substrate composition was used to illustrate the application of the Habitat Evaluation Tool (HET). Sediment transport was not modelled because mobile bed-substrate was purely sand, and hence, any sorting would result in no change in the HET output.
© Copyright Policy
Related In: Results  -  Collection

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

pone.0130228.g004: Exemplary results from the application of the modelling framework in the Treene River.The consecutive modelling steps from the ecohydrological model to the habitat models are shown. *Mapped substrate composition was used to illustrate the application of the Habitat Evaluation Tool (HET). Sediment transport was not modelled because mobile bed-substrate was purely sand, and hence, any sorting would result in no change in the HET output.
Mentions: The performance of the ecohydrological SWAT model was good for discharge (a Nash-Sutcliffe efficiency index of 0.65 to 0.82 in the calibration and 0.58 to 0.80 in the validation period), satisfying for nitrate (0.62 in the calibration, 0.74 in the validation) and total phosphorus (0.56 and 0.37), but low for fine sediment loads (0.46 and 0.10). A more detailed temporal analysis of parameter sensitivity and model performance showed that the model results were especially sensitive to groundwater parameters, indicating that the groundwater module has the highest potential for improvement. Furthermore, model performance was highest for peak discharges and the recession phase and lower for long dry periods and the resaturation phase [75], i.e., at low discharges, which are of special importance for biota. The mean monthly values of the 100 STAR runs were used in the subsequent modelling steps (monthly Q50 values exemplarily shown in Fig 4M1).

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.