Interactions at the Soil Colloid Gisela Both approaches have to be

Both approaches have to be appreciated si multaneously in terms of biology

and a general description of a multi-Iayered overall view on the structure of argu mentation

but can be a useful reference for researchers and for secondary school teachers

Geschichten über unsere Tiere zusammen mit nützlichen tierischen Informationen

Interactions at the Soil Colloid Gisela Both approaches have to beAbout 20 years ago the emphasis in soil chemistry research switched from studies of problems related to scarcities of plant nutrients to those arising from soil pollutants. The new problems have come about because of the excessive uses of fertilizers, the inputs from farm and industrial wastes, the widespread applications of anthropogenie xenobiotic chemicals, and the deterioration of soil structure resulting from certain modern agriculture practises.