ON THE RELEVANCE OF SOIL ORGANIC-MATTER TO PHYSICAL-PROPERTIES OF SOILS

Abstract

The influence of soil organic matter on selected physical properties was investigated in the variants with and without organic fertilization of 6 long-term field experiments, which were 19 to 112 years old. The soils fertilized with organic materials were characterized by lower bulk and substance densities, and higher porosity. Enhanced water retention was found in the whole pF-range tested, whereby the amounts of plant-available water on average were higher by 1.5 Vol%. The proctor-density and the optimal water content for compaction were shown to be negatively and positively, respectively correlated to the organic matter contents. It was shown that the various organomineral particle-size fractions contribute very differently to the differentiation of the physical soil behaviour due to their specific C- and N-enrichments.