Forest humus: synthesis and diagnosis Orvegetationlsoil interrelations

Abstract

With an essentially ecosystem approach this paper tries to present the problem of the soil organic matter under its most interactive aspect: soil-vegetation interrelationships. The macro-morphological study of the humus type in some forest ecosystems of the intertropical Brazilian coast faced both with dilferent approaches and bibliography resulls about organic matter of forest soils. Thus, the different uses of the humus concept, which perrneates different research, will be clarified to show further ahead our resulls both about the quantitative characteristics of humus layers and their morphological structure in order to classify the humus forms of the Resting and Atlantic forest. The resulls contradict the hypothesis, generally accepted, that in tropical regions the faster recycling of soil organic matter leads to determine humic structures of the mull-like type. The dynamics of the interactive processes arnong litter fall, mineral substrata and decomposer communities (microorganisms and fauna) is analyzed in order to elucidate lhe factors which determine the diversity of the humus form in Brazilian coastal forests.