Ythan project - Catchment nutrient budget of Meikle and Cotehill Lochs, Aberdeenshire, Scotland

Meikle (23.6ha) and Cotehill (2.7ha) Lochs are located on the edge of the Ythan river catchment area. The plant communities of both lochs appear to be changing and it is thought that this is in response to increasing levels of nutrients in the loch waters. A study was therefore commissioned by the Ythan Project in 2004 to investigate the potential sources of these nutrients. Possible sources identified included atmospheric deposition, wastewater from septic tanks and farm steading run off, faecal matter from over wintering geese and run off from the surrounding farmland. There were a number of potential problems with quantifying the potential amounts from these sources, including some difficulties establishing an exact catchment area for the lochs A comparison of potential amounts of phosphorous entering the lochs under various scenarios is reported here.