The ECN, launched in January of 1992, is a cross department UK monitoring program aimed at identification of the causes and effects of Environmental Change across the UK. Network consisted of 12 sites: one run by Forest Research. It has a sampling network of 12 terrestrial and 45 freshwater sampling locations provide long term data sets of variables thought to be of environmental importance, to allow integration and analysis of these and identify natural and man induced changes and distinguish between short term fluctuation and long term change.