Research themes

Research in the CSC is organised around five principal themes. These themes offer the chance for members of the CSC to conduct novel, cutting-edge research. They also focus on some of the major uncertainties in the development and implementation of policy and practice related to water management, for example associated with the European Commission Water Framework Directive. The principal research themes for work in the CSC are:

i. Relating physical and chemical habitat characteristics to ecosystem structure and functioning

Ecosystem structure and functioning is hypothesized to be strongly controlled by the heterogeneity and spatial organisation of sediments, morphology, flow, and temperature at various nested spatial and temporal scales. Chemical water quality also affects freshwater ecosystems, either through direct effects related to the acute toxicity of certain substances to specific organisms, or through indirect effects involving the cascading of toxicity-driven changes through food web linkages. Research in this theme focuses on the links between the spatio-temporal organization of physical habitats and the community composition and functioning of aquatic and riparian biota, and on disentangling the role of direct and indirect impacts of chemical water quality on ecosystem structure and functioning. A key aim of this theme is to provide understanding and evidence to underpin environmental management and restoration strategies, principally at the river corridor scale.

ii. Pollutant source apportionment, transport, and mitigation

The major pressures on chemical water quality in UK catchments come from nutrients (principally nitrogen and phosphorus) and organic pollutants. Successful management of these pressures will require understanding of the mechanisms, and development of measures, which reduce the loads of these pollutants reaching water bodies. Research in this theme focuses on understanding the processes involved in the mobilisation, transport and transformation of these pollutants at nested spatial scales (e.g. in-stream, river corridor and catchment scale). The aim of this theme is to identify the most important sources and pathways of pollutants within mixed urban-rural river catchments, and to use this information to direct mitigation and monitoring activities.

iii. Hyporheic zone pollutant attenuation and ecology

The groundwater – surface water interface, including the hyporheic zone, has been shown to be an important area for the cycling of nutrients, carbon and energy, and to provide habitat for a distinct hyporheic fauna. The interface is important in management terms because the European Commission Water Framework Directive requires integrated assessment of surface and groundwaters, of quality and quantity issues, of biology and chemistry. The aim of this theme is to quantify the capacity for pollutant attenuation (and it variability) in hyporheic sediments, and to understand how variation in flow and pollution pressures influences the hyporheic ecology.

iv. Defining and testing future management options

Research in this theme takes fundamental process understanding and develops evidence-based catchment management and river restoration strategies. In the context of catchment-scale management and the European Commission Water Framework Directive, these strategies must account for trade-offs and synergies among multiple goals, such as ecological status, flood protection, and nutrient attenuation. Research in this theme will address the design and subsequent evaluation of local management schemes in the context of catchment-scale pressures, and the interaction of physically-, chemically-, and biologically-focused catchment management strategies with social and economic drivers and consequences.

v. Novel modelling methodologies for catchment science

Traditional modelling approaches applied to complex environmental systems, such as river catchments and their associated freshwater ecosystems, are unlikely to be successful. This is because the causal relationships among many components of river catchments are often unknown, and others linkages are only characterised by uncertain and imprecise expert knowledge. These scenarios do not lend themselves to analysis with traditional methodologies such as numerical solutions. Work in this theme identifies and develops novel techniques for catchment-scale modelling, including systems modelling approaches, individual- and agent-based simulations, and signal processing methods. The aim of this theme is to provide new methods for interrogating existing data resources, and to develop novel techniques which are able to evaluate the impacts of alternative management scenarios on ecosystem goods and services.