river avonThis is a 4 year project, led by the Environment Agency and being trialled at a number of sites in the UK; these include the Wye, the Hampshire Avon and the Tyne. The focus being on climate change adaptation, through the introduction of tree planting, the shade from which helps to keep temperatures down in-stream, particularly helpful in the protection and support of salmonid fish populations.

We are all aware of the changes in weather and climate change, but do we consider the impacts on specific species? Many of our rivers across the UK are failing to achieve Good Ecological Status (GES) under the Water Framework Directive for fish; this can be for a number of reasons – point source or diffuse pollution, barriers to or loss of spawning habitat etc but also with warmer temperatures and increased demand on supply – our rivers and streams can on occasion be running shallower and warmer. This also prompts greater concentration of contaminants within the watercourse and can be linked to eutrophic conditions or algal blooms, all of which present difficult or toxic conditions for fish. Salmonids (the Salmon and Trout family) also experience a thermal tolerance limit; effectively a temperature level beyond which effectively means they cannot exist and would cause their bodies to shut down.

One way of creating cooler river temperatures is through a natural, dappled shade from woodland along the river corridor. The research behind this project has undertaken survey work to understand and identify current riparian (river corridor) woodland coverage, and furthermore the key areas to enhance this.

Details of the pilot projects are available here; http://www.restorerivers.eu/NewsEvents/Newsupdates/tabid/2622/ID/3002/Keeping-rivers-cool–creating-riparian-shade.aspx

And a guidance manual here; http://www.wildtrout.org/sites/default/files/news/Keeping%20Rivers%20Cool_Guidance%20Manual_v1%20%2023%2008%2012.pdf

 

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