Aplicação de dejetos líquidos suínos e seus efeitos nas propriedades físicoquímicas do solo

Abstract

Soil is an important natural resource, essential for the maintenance of life on the continents, whose balance depends, in large part, on the management and uses employed. In view of good soil management practices by agricultural activities, notably swine farming, this research had as main objective to evaluate the behavior of solutes movement, originating from pig slurry, in a soil profile, in different segments of the national Forest of Piraí do Sul, Paraná, Brazil. The hypothesis considers that the different dosages of DLS may have their movement facilitated due to physical characteristics of the soil, up to 60cm, modifying the chemical characteristics of fertility and availability of heavy metals. Thus, it was sought to recognize, along the hillside, the physical attributes of the soil that favor the dispersion of the solutes and determine the chemical properties of the soil that favor its nutrition and/or degradation. The superficial runoff was also evaluated after the application of the pig slurry and its potential for environmental quality degradation, seeking to recognize the implications of using DLS in soils as a final destination alternative for soil/water conservation. Fundamentally, the methodology is based on field experiments, with the application of DLS at doses 76, 38 and 0 m3 / ha determined based on the soil demand for nutrients present in the pig slurry and its potential to make it available to the soil. This determination was based on soil physical and chemical analyzes that refer to porous space and texture, characteristics of the assortment complex and oxide content. Thus, after auger drilling, 3 experimental plots of 10m2 were selected, in a slope in the Piraí do Sul National Forest, chosen as the study area. Gutters were installed for surface runoff monitoring after pig slurry application. The aforementioned analyzes were again performed to understand the processes because the soils passed. In the studied slope, the soils of the plots were classified as Oxisol. Soil physical attributes such as macroporosity and microporosity can be considered factors that favor the dispersion of solutes present in the DLS, intensifying their interactions with the soil at depths beyond the cultural profile, especially regarding exchangeable Al, P and C organic of the assortment complex of soils. P, K and C organic favored the nutritional enrichment of soils, but they were not enough to increase their fertility status, since CTC and pH, as well as Ca and Mg did not contribute effectively to the fertility improvement. The existence of the heavy metal Arsenic considered contaminant was verified, even before pig slurry application. However, the overdose of 76 m3 /ha disposed Cobalt, Cuprum, Zinc metals in the soil in concentrations that can be considered soil contaminants and quality degradants. Disposal ofpig slurry in soils is important for the swine viability, however, good soil management practices should take into account their ability to receive waste according to the nutritional demand of the soil and its ability to assimilate nutrients and nutrients other inorganic components such as heavy metals.