Produção orgânica no município de Seropédica: avaliação de sua sustentabilidade e o seu impacto nos atributos químicos e biológicos do solo

Abstract

Interest in organic agriculture has increased due to growing public concern with the quality of the food it consumes, the insecurity caused by rising food crises contamination and also aimed at environmental preservation. Organic agriculture offers numerous environmental advantages compared to conventional agriculture, since it is geared to improving biodiversity, restoring the natural ecological balance, soil conservation and water resources. Therefore, it is important to understand how and if these improvements are occurring in the environment and the soil in which agricultural systems are installed compared to other systems of occupation of areas. The purpose of this study was to evaluate the soil of organic production farms in the municipality of Seropédica- RJ, belonging to producers of the SerOrgânico organization, as well as areas of pasture and preserved forest. For this, the work was divided into three chapters. In the first, a questionnaire was applied based on the ministry of agriculture producers notebook for all farmers in the association. It was clear that all producers have a great sense of the importance of producing quality food and they know the main techniques for this purpose. However, the difficulties that pass are the same as those faced by all small brazilian producers are marketing difficulties, lack of access to financial credit and technical assistance. In the second chapter, soil samples were collected for evaluation of fertility, grain size analysis, chemical and grain size fracioanamento organic matter and analysis of bacterial diversity by independent analysis of culture (DGGE). The areas of organic farming showed no soil fertility results that express the positive effects of cropping system. However, the attributes that most affect the fertility of the studied areas are pH, Ca, H + Al, P, Carbon, V%, total clay and degree of flocculation. Fractionation of organic matter showed that the more stable fractions are most related to the C present in the evaluated areas and soil management beneficially altered the structure of bacterial communities. In the third chapter, we evaluated the nutritional value of corn plants and italian style tomato conditioned to different commercial inputs of phosphorus and potassium base allowed for organic production system. Both P sources, as for sources of K, did not contribute to differences in the accumulation of dry matter and nutrients in plants of tomatoes and corn, however the italian-type tomato productivity averages were higher than 44 t / ha-1 when treatments they were associated with castor bean, showing that it is a viable alternative sources of fertilizers to organic producers.