We calculated balances for cadmium (Cd), copper (Cu), lead (Pb) and zinc (Zn) on basis of field-specific data for agricultural land use for 48 sites of the Swiss Soil Monitoring Network (NABO) for the period 1996 to 2001. The balance approach used considered inputs by animal manure, mineral and waste fertilizer, pesticides and atmospheric deposition as well as outputs by crops. For the majority of the sites we found that the outputs were about in the same order as the inputs resulting in soil accumulation rates of less than 1 % of the guide value within one decade. Increasing soil concentrations larger than 1 % of the guide value within one decade were predicted at seven (Cd), ten (Cu) and twenty (Zn) of the 48 NABO-sites. Furthermore, at some sites we estimated large inputs of Zn by animal manure and of Cu by pesticides and animal manure. The predicted increase for those cases was up to 5 % of the guide value within one decade for Cu and Zn at intensive husbandry farms and up to 21 % for Cu at vineyards. In conclusion, the element balance provides the identification and prediction of temporal changes of pollutants in soil. They complement the repeated soil measurements that are being carried out in the NABO. Only with such repeated soil measurements the element balances can be validated and the real changes in soil concentration determined.
In wheat crops, pesticides can be used more sparingly without sacrificing cost-efficiency. With oilseed rape the situation is more difficult, since the reduced yields are not offset by higher revenues. These are the findings of the analysis of the first two harvest years of the PestiRed project.
Soil samples can be measured directly in the field by means of spectroscopy. Agroscope researchers have tested mobile devices and shown how to make the best use of them.
Three widely used and newly revised approaches that optimally complement each other are available to practitioners, trainers and educators. Videos and apps have been designed to facilitate their use.