Ecological catchment system analysis
Our nature-based trans-disciplinary analysis integrates ecology-based water management and spatial land use planning. We use novel tools to bridge disciplines and integrate knowledge.
Examples of projects
- Integrated ecological water management: EU-WISER, SchipHolland
- Ecological key factors: Sleutelfactoren, Abiotische randvoorwaarden, Ecologische condities
- Resilience and Resistance: Ecosystem predictability, Veerkracht, Ecosystem resilience
- Catchment analysis: 5-S-Ecologische modellering, Grondwater, Leefgebieden Noord-Brabant, Vernatting
In order to make the proper choices in ecological river and catchment management one has to understand the key abiotic and biotic processes (dominance and feedback interactions). To simplify this ecological complexity, while recognising the importance of scale and hierarchy, the 5-S-Model was designed. This conceptual model provides guidelines for catchment management (Verdonschot et al., 1998, 2000, 2014). Five groups of key factors are distinguished, hierarchically ordered for streams: System conditions (the processes related to climate, geology and geomorphology), Stream hydrology (the hydrological and hydraulic processes), Structures (the morphology related processes like erosion and sedimentation), Substances (the biochemical processes) and Species (the response to the functioning of all above mentioned groups of key factors expressed in the community functioning). Species and their communities are the actual goal of ecological stream management and rehabilitation.
By improving the understanding of ecosystem functioning using ecological resilience and resistance as integrated measures makes ecological concepts applicable in the practice of restoration and the delivery of ecosystem services, like biodiversity. Benthic macroinvertebrates of lowland streams evolved under natural hydrologic disturbance regimes and carry traits to either resist high flows (resistance traits) or to recover quickly (resilience traits). Understanding the trait adaptations associated responses of macro-invertebrates under different disturbance regimes will enhance our understanding of survival mechanisms under multiple stress conditions and will tell about resilience and resistance. In stream mesocosms, we mimicked lowland stream spates by increasing current velocity above organic habitat patches and observed the response of Trichoptera larvae. It appeared that each combination of morphological and behavioural adaptations developed individually for each species under niche- specific conditions (Verdonschot et al. 2012, 2014). Furthermore, more tolerant species from the disturbed end of the gradient showed more mobility and flexibility than the species occurring under more or less natural stream conditions. This is consistent with the hypothesis that mobility is an adaptation of tolerant, ubiquitous species. Mobility is an resistance adaptation of r-strategists while seeking refuges is a resilience adaptation.
Ecological catchment system analysis
Restoration of ecosystems has moved from individual sites, single lakes or stream stretches towards landscapes and catchments. Therefore, we distinguish Operational Restoration Units (ORUs). That is a natural system based delimitation of the spatial borders of a restoration project, and encompasses the wider socio-economic drivers. An ecological catchment (or ORU) system analysis differentiates between three cycles: an abiotic, a biotic and a socio-economic or societal cycle. Within the abiotic cycle the system conditions, hydrology, morphology and chemistry of the catchment or ORU are analysed for the current and future situation. The biotic cycle focusses on the key ecological processes and responses driving the ecosystem functioning. The societal cycle includes the direct and indirect socio-economic actors that affect the current and future ‘surroundings’ of the project. With this conceptual approach multiple stressors can be identified and multiple measures advised based on an integrated approach over different spatial and temporal scales to reach a sustainable nature-based functioning (eco)system.
- Verdonschot, R.C.M., van Oosten-Siedlecka, A.M., Ter Braak, C.J.F., Verdonschot, P.F.M. (2015) Macroinvertebrate survival during cessation of flow and streambed drying in a lowland stream. Freshwater Biology 60(2): 282-296
- Verdonschot, P.F.M., Besse-Lototskaya, A.A., Dekkers, T.B.M. & Verdonschot, R.C.M. (2014) Directional movement in response to altered flow in six lowland stream Trichoptera. Hydrobiologia. Hydrobiologia 740: 219-230
- Marzin A., P.F. M. Verdonschot & D. Pont (2013) The relative influence of catchment, riparian corridor, and reach-scale anthropogenic pressures on fish and macroinvertebrate assemblages in French rivers. Hydrobiologia 704: 375 - 388
- Verdonschot R.C.M., Keizer-Vlek H.E. & Verdonschot P.F.M. (2011) Biodiversity value of agricultural drainage ditches; a comparative analysis of the aquatic invertebrate fauna of ditches and small lakes. Aquatic Conservation: Marine and Freshwater Ecosystems 21: 715-727
- Verdonschot P.F.M. (2009) Impact of Hydromorphology and Spatial Scale on Macroinvertebrate Assemblage Composition in Streams. Integrated Environmental Assessment and Management 5(1): 97–109