Our overall aim is to contribute to an interdisciplinary understanding of the hydrological and biogeochemical functioning and behaviour of catchment systems and the hydro-ecology of associated river networks and landscapes. The linking theme of our research is the prediction of integrated consequences of climate change on physical, chemical and biological characteristics of water resources by using insights from individual locations and extrapolating such predictions to other regions within an interdisciplinary framework. Below is a list of current active research themes at the NRI.
Runoff generation in the landscape
(mostly funded through Leverhulme Trust and NERC)
Most of our work is articulated around the inference of catchments hydrological response, especially the understanding of how they retain and release water, from hydrometric, hydrochemical and isotopic tracer time series. In order to assess catchment function or behaviour, focus is on the investigation of spatially and temporally variable runoff generation mechanisms, water flow paths, biogeochemical fluxes, storage fluctuations and transit times. Detailed geological, topographic and pedologic data are also studied using GIS so as to identify the structural landscape characteristics responsible for the observed dynamic catchment behaviours. All projects currently undertaken involve multiple catchment monitoring, including nested experimental designs, so as to examine scale-dependent processes and controls. Concepts such as hydrologic connectivity, self-organization and pattern emergence are pointedly used in order to aid process understanding, conceptualization and prediction in heterogeneous landscapes. Methodologies are also tested and compared in search for scientific approaches that would be easily transferable to various geographic environments.
Process-based hydrological modelling
(mostly funded through Leverhulme Trust and NERC)
Modelling projects undertaken at the NRI comprise a diversity of approaches (e.g. conceptual or numerical, lumped or semi-distributed); however all are informed by the hydrological processes knowledge gained from field experiments. The incorporation of that knowledge into catchment modelling is meant as an attempt to constrain models to give “the right answers for the right reasons”. Recent work has led to the use of geochemical and isotopic tracer data to decide upon appropriate lumped model complexity and structures. Further work is underway so as to develop semi-distributed modelling structures based on spatial discretization of topographic and soil information.
Catchment hydrology and instream ecology interface
(mostly funded through Leverhulme Trust, Scottish Executive, Atlantic Salmon Trust, English Nature, Tay Board, Scottish Natural Heritage)
Our collaborative, interdisciplinary work aims at increasing the research knowledge on hydrology, river morphology and other environmental factors that are known to impact aquatic habitats at different scales. Key research subjects include groundwater-surface water interactions in stream hyporheic zones, habitat use by salmonid fish, the spatial and temporal variability of abiotic factors (e.g. stream temperature, dissolved oxygen) and the impacts of river regulation (e.g. dams, hydropower plants, river diversions) on the structure of stream ecological communities. The identification of key flow indicators is an especially important research area as they are meant to help us quantify the consequences of flow change on the behaviour of spawning salmons. The concept of hydrological connectivity is, again, used to link the hydrological processes occurring in the landscape to the ecological patterns observable in associated riverscapes.
Catchment inter-comparison
(mostly funded through Leverhulme Trust)
Our extended network of monitoring sites and our successful international collaborations have given us the opportunity to launch wide-ranging inter-catchment comparison exercises. We believe that using insights from different geographical environments will allow us to better understand hydrological and ecological dynamics, particularly catchment ecosystem responses to climate change. With that regards, the Northern Watershed Ecosystem Response to Climate Change (NORTH-WATCH) project is a good example of our research philosophy as it focuses on some high latitude and lowland cold regions of the globe which suffer from sparse meteorological and hydrometric records while they are expected to be strongly affected by climatic changes. We therefore aspire to increase our scientific knowledge on such regions by bringing together many scientists from around the world.