Conceptual Sampling Design for Tracing Agropollutants on a Catchment Scale

This chapter provides guidelines for designing a sampling programme for tracing agricultural pollutants using stable isotope techniques at different catchment scales. This sampling template could be considered for the application of various tracers with respect to local needs and study objectives. The template is based on a series of overlapping mixing models that use ‘triple sampling points’ to identify major sources of pollution by estimating pollution budgets in different subcatch-ments along the water flow pathways. This framework can be further specified, and a more detailed sampling network can be developed after analysing the results obtained from the initial sampling. Step-by-step technical instructions on how to collect and preserve water samples for stable isotope analyses can be found in a separate docu-ment published by the International Atomic Energy Agency as a Standard Operating Procedure (Skrzypek in Sampling and isotope analysis of agricultural pollutants in water IAEA TECDOC SERIES. International Atomic Energy Agency, Vienna, pp. 2–21, 2018).