LTLS Freshwater Ecosystems ("LTLS-FE"): Analysis and future scenarios of Long-Term and Large-Scale freshwater quality and impacts

Long Term Large Scale - Freshwater Ecosystems (LTLS-FE):

Rivers in the United Kingdom have in the past and the present been subjected to a range of pressures due to the release of chemicals and by-products, such as domestic wastewater, acid rain, the application of nutrients and pesticides to soils, and the use of domestic products such as medicines. While some of these pressures (e.g. acid rain, wastewater discharges) appear to have eased over recent decades, others (e.g. pesticides, nutrients) remain and may be increasing. In addition to these pressures, climate change is also expected to impact on the quality of UK rivers, for example by leading to changes in anthropogenic chemical use, by changing the amount of water in rivers and thus how much water is available to dilute chemicals, by making storms and floods more or less frequent, and by changing the volume of chemicals washed into rivers from the land. Climate change could also influence freshwater biodiversity, for example by increasing the exposure of organisms to pulses of toxic chemicals during storms or by increasing the likelihood that UK rivers are invaded by alien species which outcompete native species.

The quality and health of UK rivers are of great interest to many groups - the general public who rely on waters for recreation such as swimming and angling, to the regulators who are tasked with improving and then maintaining water quality, and to water companies who partly rely on rivers for drinking water supplies. It is therefore important that we try to understand as well as possible how water quality and health might be affected by future changes in the way society uses chemicals and water, and how these might be further affected by climate change.

This is a complex problem, because the factors that drive river quality are many and they will vary over time and from place to place. This project will tackle the problem by developing a model that will use these drivers to predict how chemical inputs, river quality and river health will change in the context of different 'pathways', or scenarios of change in society and climate. By doing this, we will provide a range of 'projections' of future river quality and health. These projections will help scientists and policymakers to understand the main factors controlling river quality and health. This will help them to develop solutions to manage and ameliorate possible changes in the factors that influence river quality and health, with the goal of maintaining and improving the state of UK rivers in a changing world.

As well as our projections of possible futures for UK river quality and health, we will make the data and model code available to all at the end of the project. This will provide other researchers with possibilities such as changing the mathematics of the model, adding new chemicals as they emerge, or applying the model to other countries and parts of the world.