Trends in stream water quality in Environmental Change Network upland catchments: the first 5 years

Hydrochemical data from catchment streams at three Environmental Change Net work (ECN) upland catchments in north-east Scotland, south-east Scotland an d northern England have been subjected to statistical analysis to separate the components due to long-term trend, season and Row. The relative varianc es due to each are presented for pH, Ca, SO4-S. NO3-N, DOC and Cl. Long-ter m trends have been identified with increases in concentration for NO3-N and DOG, decreases in SO4-S concentrations, along with short-term seasonal flu ctuations. Application of this trend technique has allowed the detection of changes and contributed to an improved understanding of catchment behaviou r. (C) 2001 Elsevier Science B.V. All rights reserved.