Abstract
SUMMARY. Statistical analysis has been carried out on 11 years (1965–75) weekly data of nitrate concentrations and discharge values from the R. Frome (Dorset). The results have shown a trend over the 11‐year period with nitrate concentrations increasing by 0.11 mg NO3‐N 1−1 per year. A predictive model for nitrate concentrations for 1976 was made and even though discharge conditions were extreme, the mean predicted nitrate concentration of 3.37 ± 0.136 mgNO3‐N1−1 was very close to the observed mean nitrate concentration of 3.44mgN03‐N1−1.