A few decades ago in The Netherlands in the same way as in a number of other West-European countries a development started of excessive growth of animal husbandry. While in former agricultural production where animals were involved more or less a balance existed between the number of animals to be held on a certain farm, and the area available for feed and fodder production, this balance was now disturbed by the import of huge quantities of feed and raw materials for feed production. This has led to the situation that a mineral excess from animal manure exists for The Netherlands as a whole. In specific parts of the country, especially the sandy area, mineral availability has grown to excessive amounts. The environmental problems involved are related to:-leaching of nitrate to groundwater at a concentration level which causes unsuitability for drinking water purposes;-accumulation of phosphorus in the soil profile, and in case of P-saturation of the soil, leaching to groundwater and surface water, thus inducing eutrophlcation problems;-leaching of K to groundwater at a concentration level exceeding the potassium standard;-accumulation of heavy metals in soil, especially Cd, Cu and Zn, at a level which may induce malfunctioning of soil, both with respect to water quality, and to crop yield and crop
composition.
Identifying the potential of some heavy metals toxicity in urban and peri-urban cropping systems in Sierra Leone