Determinação de íons metálicos disponíveis e parâmetros físico-químicos em solos com cobertura vegetal natural do oeste do Paraná

Abstract

Population growth coupled with economic development has brought about significant transformations in ecosystems. The increase in anthropogenic activities has intensified the destitution of natural vegetation in most of the river basins, since they do not resist the rapid expansion of the agricultural frontier and urban projects. In this context, there is a need for soil studies, especially in areas with no direct environmental impact. The determination of the natural composition of metallic elements and complementary parameters of the soil is an important step towards the definition of quality reference values, as well as a subsidy for the construction of legislation aimed at monitoring and intervention compatible with local reality. This work aimed at the characterization of six types of soils (PV, GX, MD, LV, NV, RR) collected in forest remnants of areas with natural vegetation cover of the Western Region of Paraná. The following parameters were determined: physical, chemical and chemical parameters (granulometry, pH, organic matter, organic carbon and phosphorus) according to Embrapa methodologies and available metallic elements (aluminum, calcium, cadmium, lead, copper, chromium, iron, magnesium, manganese, potassium, sodium and zinc). The complementary physical and chemical parameters presented variations among the soil classes with highlight to higher levels of clay + silt in LV and NV soils and lower PV soil content. The metal ions with the highest concentration (mg kg⁻¹) were found for Al (489,28) in soil LV; Ca (2342.26) in the MD only; Cu (1.02) for soil NV; Fe (4.62) not only LV; Mg (11.61) for the PV soil; Mn (468,42) not only NV; K (130.80) for RR soil; Na (22,97) in soil GX; and Zn (11,42) for soil NV. In general, the lowest Al, Ca, K, Na, Zn and Mn contents were found in the PV soil. With the application of statistical analysis of main components it was possible to notice that the six soil classes present different concentrations among themselves, separating them into 4 small groups, GX; PV; LV and NV; and MD and RR.