1. 1 Samples are stored in a cold room at optimal storage temperature and humidity.

2. 2 Quality parameters in the field The Swedish Environmental Protection Agency produces Standardised instructions which determine – in detail – why, how, when, where, how much and how often, field samples should be taken. These instructions exist for several variables concerning soil chemicals in e.g. Drainage water; ground water in catchments, and in observation fields etc. Each variable should also be analysed according to a Swedish Standard recognised analytical method.

3. 3 Laboratory characteristics and standards The quality of laboratory analysis of important soil chemicals is strictly controlled by SwedeAc (Laboratory Accreditors) who make annual inspections of accredited laboratories. Quality control analysis protocols must be followed by accredited laboratories. Such protocols exist for a number of soil chemical analyses e.g. P, Phosphate P, Nitrate N, Ammonium N, Total P and Total N.

4. 4 Automatic water chemistry analyser in an accredited lab

5. 5 Presentation of results For both monitoring programmes (Agricultural fields and Small Catchments) yearly national reports are made presenting summarised results. In addition, a yearly documentation and data compilation is made for each of the catchments with the purpose to check data and to register changes, errors, etc. Evaluations of results from the individual catchments and national evaluations are made with longer time intervals.