ABSTRACT
In 1981, the Working Group of the International Society of Soil Science passed a resolution regarding the need for establishing an international society for the study of humic substances (International Humic Substances Society). The Dahlem workshops are organised specifically to take stock of the data and prospective developments in this most important interdisciplinary problem, which once more emphasises the scientific importance of the theory of formation, structure and function of humic acids. While considering the physiological action of humic acids and fulvic acid the readers inevitably come to concepts of the similarity of animal and humus as propounded by Vernadskii, about the inevitable formation of a system of humic substances ensuring contemporary forms of terrestrial life. The general principle follows from this that for accumulation of humus in soils it does not suffice to add additional quantities of organic matter in the form of plant residue, manure or other organic material.
