Atributos químicos de solos hidromórficos em área de preservação permanente no sudoeste do Paraná

Abstract

Hydromorphic soils are humid areas of ecosystems naturally saturated by water permanently or periodically, shallow, rich in organic matter, with a particular physical-chemical environment, presenting native floristic and fauna diversity, adapted to water conditions of high importance to the natural environment, mainly to water courses. Therefore, the work aimed to evaluate the chemical and physical attributes, the environmental importance of the studied areas, presenting the characteristics and weaknesses of these hydromorphic soils in areas of permanent preservation in southwestern Paraná, promoting the concept of preservation of these ecosystems. The work was carried out with the collection of eight sampling points in four areas of permanent preservation in the Jirau Alto River Basin, which supplies the municipality of Dois Vizinhos, with three areas of hydromorphic soils and a fourth area of well-drained soil, in the winter seasons. it's summer. Afterwards, physical and chemical analyzes of the soil weremade and, subsequently, the samples were subjected to analysis of variance and when significant, the Scott Knott means comparison test was applied at the level of 5% probability. The moisture content found for High Humidity 81.8%, Medium Humidity 61.5%, Low Humidity 30.2% makes it possible to visualize high humidity characteristics in hydromorphic soils, differently from well-drained soils, witnessing 23.3% humidity. A high content of silt was observed in the composition of the soils, with High Humidity (71.9%) being the area with the highest content among the areas, while the control area presented 41.8%. Poorly drained soils showed high levels of MOS and acidity, and for the other nutrients Ca, Mg, P and K there was little variation between the sampled areas. The hydromorphic soils of the Southwest of PR showed a higher content of MOS, acidity and less availability of nutrients than well-drained soils. Such characteristics limit its use for agricultural crops, but they manage to maintain the native vegetation, contributing to the maintenance and protection of the ecosystem, as well as in the filtration of water and in the supply of the water table. Practices to promote the conservation of these areas must be improved so that farmers understand the importance of preservation and the consequences of the accelerated process of anthropization of hydromorphic soils.