There is a significant increase in copper and zinc concentrations in intensively farmed grassland plots in Switzerland. This may be attributed to the regular application of large quantities of farmyard manure, which contains the micronutrients copper and zinc. + Get the most important news from Switzerland in your inbox Copper and zinc can be expected to accumulate in the soil, particularly if farmyard manure is used for several years and is greater than the amount of nutrients absorbed by the grass. This was announced by the Federal Office for the Environment (FOEN) on Friday. The findings are based on the results of the seventh National Soil Monitoring of Switzerland (Nabo). In special crops such as viticulture, increases in copper concentrations five to six times higher than the guideline values were recorded. These observations may be explained by the use of plant protection products containing copper, which are used in viticulture to combat mildew, among other things, the ...