Debatable problems of modern soil chemistry

摘要

This paper is the edited text of the author's lecture presented at the Seminar on Theoretical Problems of Soil Science. It is a brief review on the evolution of some basic terms and concepts of soil chemistry in the 20th century. The advantages and limitations of some common soil chemical indices are shown in the light of modern concepts. The basic terms of soil chemistry are analyzed, such as cation exchange, soil acidity, soil chemical composition, etc. The terms "fulvic acid," "humic acid," and "humin" are considered, with particular attention paid to the differences between native and isolated humic acids. Some urgent tasks of soil chemistry are outlined.