Análise de áreas degradadas para recuperação ambiental na área de proteção ambiental do Cariri Paraibano.

Abstract

The conservation of the natural resources of the Caatinga biome is intensely associated with the mitigation of desertification, a process of environmental degradation that occurs in arid, semi-arid and dry sub-humid areas, characterized by soil degradation, water resources, deforestation and biodiversity extinction , Directly affecting the productive capacity of the land, reaching social and economic relations. The objective of this work was to analyze degraded areas for environmental recovery in the Environmental Protection Area of Cariri Paraibano - APA Cariri, the area is formed by three municipalities Cabaceiras, São João do Cariri and Boa Vista, located in the state of Paraíba. Remote sensing and GIS were used in conjunction with the use of the Standard Difference Vegetation Index (IVDN) to verify the vegetation behavior. Three areas were selected within the Cariri APA, a very degraded, semi-degraded and an area Preserved, in which the respective soils were collected for chemical and physical analysis, as well as a survey of the vegetation of the preserved area. Then, the digital maps of the Cariri APA vegetation cover were generated from 1990 to 2010 and it was verified that in 20 years of temporality the Cariri Paraibano APA lost an area of shrub caatinga equivalent to 27,6Km2, with a Reduction of 61% of the existing area and in relation to the exposed soil there was a doubling of the total area in this period. The recognition of the environmental conditions of the impacted area, such as: soil characteristics, vegetation and precipitation are fundamental elements for the selection of adequate degraded areas recovery techniques, and according to the results obtained for Cariri APA, For land degradation were deforestation for energy and agricultural purposes and livestock. The results for the chemical and physical analyzes of the three areas correspond to expected results in semi-arid areas. For the degraded area the pH, P, K, Mg and MO levels, which are elements that directly respond by soil fertility, were 6.94; 1.02; 6.46; 8.13; 0.62 respectively, for the physical analyzes of sand, silt and clay were 63.76; 21.60 and 14.64 respectively. The results referring to the phytosociological survey of the preserved area were 68 individuals found, belonging to 9 species, contained in 7 families. The families that presented the greatest number of species were: Anacardiaceae, Fabarceae and Cactaceae. The most important species of importance were: Myracrodum urundeuva (Engl.) Fr.All (aroeira), Schinopsis brasiliensis Engl. (Baraúna), Caesalpinia pyramidalis (Tul.) (Catingueira) and Mimosa tenuiflora (Will.) Poir (jurema-preta). The area selected for recovery projects is adequate, firstly because it presents native vegetation composed of pioneer species and also represents areas that soil conditions are satisfactory for plant growth, with adequate amounts of chemical elements that respond for their fertility, As well as in relation to the proximity to preserved areas, that can contribute with the supply and transport of litter, seed collection, native seedlings among others.