Avaliação da qualidade do solo da área de preservação permanente da nascente de um afluente do Rio Potengi como ferramenta para diagnóstico e recuperação ambiental

Abstract

Water resources are essential for living beings. In this sense, the preservation of watercourses, springs, and their surroundings is of paramount importance for promoting the quality of life of individuals. However, soil degradation due to disorderly occupation and inappropriate use has been affecting areas legally designated for environmental preservation, such as Permanent Preservation Areas (APP) of springs. In the northeastern Semi-Arid region, this reality is intensified due to the natural characteristics of the region, which has low water availability, with rainfall concentrated in a short period of the year, high temperatures, low humidity, poorly developed soils, and sparse vegetation. In addition, anthropogenic activities, such as agriculture and livestock farming, are carried out in areas increasingly close to existing water bodies, which contributes to the progressive impoverishment of both soil and water quality. The removal of riparian vegetation increases the vulnerability of the soil to erosion, transforming these areas into diffuse sources of pollution for aquatic systems. In this sense, the objective of this study is to evaluate the most sensitive variables related to soil quality in the APP of the source of the Gameleira Stream, a tributary of the Potengi River, located in the quilombola community of Gameleira de Baixo in São Tomé/RN, in order to support future proposals for environmental recovery techniques that can be applied to the area, taking into account the current soil quality. To this end, 11 composite soil samples were collected, each consisting of a mixture of five simple samples. Seven samples were collected from the area degraded by anthropic activity, presenting exposed soil, and four samples from a conserved area, with vegetation cover, to serve as a reference for soil quality. The samples were subjected to analysis of physical attributes: particle size, soil density, particle density, and total porosity; in addition to chemical attributes: pH, electrical conductivity, available phosphorus, and organic matter. The results obtained demonstrate the loss of soil quality due to the erosive processes existing in loco, caused mainly by the development of livestock activities and the presence of invasive plant species in the vicinity of the spring. Thus, highlighting the need to protect the area, as well as to promote environmental recovery techniques to improve soil quality.