DYNAMICS OF ORGANIC WASTE DECOMPOSITION

Abstract

Taking into account that the organic material of the soil is an important component in the structure and functioning of ecosystems, mainly in geochemical changes and soil fertility, and that the dynamics of its mineralization depends mainly on the activity of microorganisms, the type of organic molecules that predominate in the materials that reach the soil and the environmental conditions such as temperature and precipitation, the following work was carried out with the aim of evaluating the changes in the organic materials that reach the soil depending on location in the profile soil. The modified Litter Bags methodology was used, placing 300 g of plant waste material, mainly grasses, in plastic bags with holes of approximately 1 mm. White bags were used to simulate the decomposition of the material on the soil surface (placed on the surface) and black (buried 20 cm) to simulate the decomposition within the soil profile. The total number of bags for each case was 12, in such a way that a sampling of three bags was performed for each condition at the beginning of the trial and at 22, 35, 56 and 78 days after establishment. In the initial sample, the composition of the plant tissue, the dry matter and the moisture content were determined. In the intermediate samplings, the dry matter and humidity were measured and in the final sampling, in addition to the above, the chemical composition of the plant tissue was determined again. It was evidenced concluded that the loss of dry matter which is an indicator of the decomposition rate of the material, was larger in the buried organic material than in that placed on the soil surface due to the moisture content which favored the process of mineralization on the buried one.