Degradação, avaliação ambiental e recuperação de áreas degradadas em Camalaú-PB, Semiárido Brasileiro.

Abstract

The function of Permanent Preservation Areas (APPs) is to protect water resources, landscape, biodiversity, geological stability, and soil. The research sought to evaluate the degradation process and apply techniques to recover degraded areas in the municipality of Camalaú-PB, in the Upper Course of the Paraíba River, Brazilian Semi-Arid. Different techniques were used: 1st) Analysis of the temporal behavior of the vegetation cover of the municipality of Camalaú-PB between 1985-2020, using remote sensing, based on MapBiomas, and statistical analysis by Mann-Kendall and Pettit; 2nd) Soil management and conservation as a strategy for recovering degraded areas by constructing contour lines and contour lines using tree pruning, stones, and used tires and then implementing agroforestry systems; 3rd) Mapping of soil fertility in the recovery process through a simplified parametric model of natural soil fertility using geoprocessing; 4th) Evaluation of soil moisture profile in managed and degraded areas of a semiarid region determined by the greenhouse and electric oven methods, in which the data were analyzed using R® software through the longitudinal mixed effects model.; 5th) Analysis of the biometric parameters of development of 11648 correlating with the variables collection time, precipitation and topographic elevation. The spatiotemporal change of the Caatinga Biome over the 36-year series in the municipality of Camalaú-PB was influenced by several factors, such as use and occupation, management practices adopted by farmers, type of exploration and climate change. The areas susceptible to desertification in the study area increased. The mechanical practice with stone cords and tires, in addition to helping to control the erosion process, also enabled the formation of seed banks. The cultivation of agave on contour lines allowed the formation of cordons that blocked the speed of water and helped its infiltration, preventing the erosion process. In the agroforestry system, the species of mandacaru (Cereus jamacaru DC) and elephant ear palm (Opuntia stricta Howard) presented the highest survival rates. The low content of P, Ca2+, Mg2+ and K+, and organic matter (OM), combined with the high Potential Acidity (H++Al3+) and total CEC influenced the classification of the natural fertility of the soils as Very Low and Low. The lower altitudes showed greater soil water retention at all depths. The degraded area presented lower moisture levels at the depth of 0-10 cm compared to the managed area. The cultivation of palm and agave promoted greater water retention in the soils in the managed area. The production of the Embrapa 11648 Hybrid agave cultivated in contour lines as a mechanical-vegetative practice in sloping areas and in the recovery process showed positive results regarding plant growth and development.