Vantagens do Sistema Agroflorestal Sobre o Sistema Agrícola Convencional no Domínio do Semiárido

Abstract

In the face of the expansion of agroecological cultivation and the hitherto use of areas of application of conventional agriculture in the semi-arid region, it showed to be necessary a deeper and more scientific study for the detection, through a comparative analysis, of the main differences between these two types of cultivation, observing the local space in its peculiar characteristics and impact. This study aimed to analyze the agricultural practices in properties of conventional and agroecological use in two areas of the same municipality – Nova Olinda/CE, with the same geophysical characteristics and that they have been using the specific practice of cultivation for more than ten years. This was an exploratory and descriptive study with a quanti-qualitative approach, using for data collection: formulary, systematic direct observation, interview, collection and analysis of soil. In relation to the techniques of cultivation, the agroforest model was put in evidence for using polyculture, partnership with other plants in which was included around 29 native species, incorporation of organic remains, selective cut and direct planting. Other techniques which were equally important in that system and widely used by this cultivator were: collection and extraction (fruits, roots, leaves, honeycombs, etc.), which involve horticulture (fruits and vegetables) and apiculture. In this model of cultivation, agrochemicals were not used, since the intention was to reach the natural control through the biological chain using vegetable species. As the benefits of those techniques, it was identified the maintenance of the microclimate which was adequate for the biology of the soil; control of weeds and erosion; greater permeability to water; protection of the soil against direct sunlight, rain and wind; stabilization of eroded areas; and promotion of biodiversity. In the conventional model, mono and partnership are the adopted types of cultivation; the practices of soil preparation include the cut and removal of remaining stems, fire, use of mechanical rakes and weeding. As consequences, it was identified an abrupt diminishing of the biodiversity, reduction in the capacity for vegetal restitution and soil bareness with the consequent increase in the erosion index and diminishing of the fertile layer. The mineralogical indexes of soil fertility are higher in the Agroforest System (AFS), and, due to the techniques used by the cultivator, they have a tendency to increase; on the contrary, in the Conventional System (CS), the techniques used generally diminish the soil fertility, thereby taking the soil to more critical indexes. In relation to productivity, the Agroforest System was put in focus due to its different productions, which provide a higher number of sources of income with consequent profitability. It was grasped then that in terms of productivity and profitability, the Agroforest System was more advantageous to the cultivator due to various reasons, among them it was highlighted: more sources of income, greater production per hectare and more security and terms of production, not only at the environmental level but also at the economic one. It was identified that the Agroforest System showed excellent results and it outperformed at the level of soil and ecosystem conservation, as well as in productivity and profitability, the adopted Conventional System. Therefore, the Agroforest model is considered profitable and favorable to the adoption by the cultivators from the semi-arid region of the Brazilian North-East