SEDSRES

Quantifying sources and residence time of contaminated sediment in human-impacted river basins: an integrated approach

 Partecipanti

Mappa

 Word cloud

Esplora la "nuvola delle parole (Word Cloud) per avere un'idea di massima del progetto.

 Obiettivo del progetto (Objective)

'The widespread and costly environmental impacts of sediment and associated contaminants on aquatic ecosystems are recognised by scientists, land managers and policy makers worldwide. While considerable effort is being made to reduce sediment and contaminant fluxes in European river basins, longer-term storage of contaminants in sedimentary sinks presents a credible threat to achieving EU water quality targets. Sedimentary sinks could become contaminant sources in the future. In this context, this project aims to develop an integrated approach for quantifying diffuse sources and residence times of contaminated sediment in river basins affected by industrial, mining and agricultural pollution. Development of the integrated approach will be undertaken in the River Tamar in south-west England, which is a predominantly agricultural basin with an extensive metal mining history. As such it offers a natural laboratory for exploration of key sediment-associated pollutants. The approach utilises fallout radionuclides and other sediment tracers to quantify diffuse sources of sediment and associated contaminants stored in channel deposits and transported in suspension over event and seasonal timescales. Potential sources include different agricultural land uses, mining waste deposits, channel banks, as well as secondary sources, including in-channel deposits and floodplains. The residence time of contaminated sediment in soils and channel sediments will be estimated by application of models which employ fallout radionuclides as chronometers over a range of timescales. Findings from the source and residence time analysis will be synthesized within a sediment budget framework, which can be used to directly underpin management decisions. This will provide river basin managers with a powerful tool to assess the potential impact of sedimentary sinks as secondary sources of water pollution in European rivers, a key requirement to meet the challenges of the Water Framework Directive.'

Introduzione (Teaser)

Environmental impacts of sediment and its associated contaminants on aquatic ecosystems have long been recognised by scientists, land managers and policymakers. Long-term storage of pollutants in sediments presents a source of contamination in the future, threatening EU water quality targets.

Descrizione progetto (Article)

The SEDSRES project developed an integrated approach for measuring sources and removal times of contaminated sediment in river basins affected by industrial, mining and agricultural pollution.

Field sampling was carried out in the catchment of the River Tamar in south-west England.

The region is an agricultural one with a history of metal mining, making it ideal for investigating key sediment-associated pollutants.Laboratory analysis used sediment tracers to measure the transport in suspension of different sediment sources and associated contaminants stored in water channel deposits.

The removal time of contaminated sediments was estimated in order to provide a time scale for river and catchment recovery from sediment contamination.

The Australian soil erosion model SedNet was used for the first time in a European context.

This provided unique insight into the way river basins respond to land use and recent environmental change not otherwise possible from conventional monitoring alone.While considerable effort is being made to reduce the amount of diffuse water pollution from agricultural land (DWPA) in rural lowland catchments, little attention has been given to the potential role of sediments stored in channels.

This knowledge gap could compromise management of the catchment.

Therefore, the work conducted by the SEDSRES project will directly contribute to improving catchment management decision making.

It will also help achieve EU Water Framework Directive (2000/60//EC) goal calling for United Kingdom rivers to reach good ecological status by 2015.