Studies On Humus And Aggregate Formation

Abstract

Introduction It has been recognized that organic matter serves as a granulating agent in soils. Though the exact nature of organic substance associated with the aggregate formation is not completely understood at the present moment, it is certain that the role of organic matter in soil structure depends on the type of organic matter present. :Mere humus seems to not necessarily possess the power of aggregating soil particles, and the process of the decomposition of organic matter seems to be more important than its presence in improving the soil structure. Actually it has been found by many investigators that waterstable aggregates are formed in the rhizosphere of perennial grasses. Besides the binding action of roots of grasses and that of microbial tissues, some organic matter mainly produced by microbes in the rhizosphere of grasses is considered to be associated with the aggregate formation.