Avaliação dos atributos do solo sob diferentes tipos de preparo e emprego de plantas de cobertura em sistemas de produção orgânica

Abstract

The concern with environmental sustainability has been frequently discussed and shown in the most diverse sectors of society. The need to seek sustainable productive systems has also been recognized in agriculture. Reducing the use of synthetic inputs, the adoption of systems that preserve soil quality, reduce the need to use water for irrigation, improve the microclimate of cultivation and, the same time, improve the productivity indexes are aspects that are sought in these systems. The objective of this paper was to evaluate the dynamics of the use of green covers in the decomposition and release of nutrients, as well as the use of a test crop, Eggplant (Solanum melongena L.). For this, an initial characterization of the area, located in Seropédica, RJ, seeking to verify the homogeneity of the site, where the following properties were analyzed: evaluation of soil fertility, soil resistance to penetration, stability of aggregates, and soil density. Subsequently, green manures were cultivated among them: Brachiaria, (Brachiaria brizantha), millet (Pennicetum americanum), crotalaria (Crotalaria juncea), forage peanut (Arachis pintoi), cocktail of previously mentioned species, and spontaneous. When the cutting point was reached, these mulches were divided into plots that were either turned over or just deposited on the ground, thus simulating direct planting. The eggplant was transplanted in order to observe the changes in soil quality and evaluate the productivity in each treatment. It was verified that the productivity of eggplant did not differ statistically as to the management adopted, however, in percentage the covering composed by the cocktail provided a higher productivity in the treatment where the soil was not turned over.