Alterações na fertilidade do solo e teores de metais pesados em solos cultivados com videira

Abstract

Cultivation can substantially alter the soil characteristics either to improve or decrease its fertility, depending on the manangement practices. Vineyard soils are sensitive to soil changes due to the intensive chemical input. The research was performed aiming to study the soil fertility changes in vineyards soils of the São Francisco valley. Were selected eight grape farms posing different cultivation time spans (5, 6, 8, 10, 12, 15 and 16 years) as well as in Caatinga areas which were taken as a reference. The folowing soil fertility characteristics were determined: pH, exchangeable contents of Ca, Mg, Na, K and Al; H+Al; available P; organic carbon; sum of bases, CEC, Al saturation and base saturation. These analyses were carried out in soil samples from the 0-20 and 20-40 depths. The results analyzed using the F test, correlation and Tukey´s test. The results showed that soil fertility was changed according to the lenght of cultivation as compared to reference areas. The soil organic matter contents were increased in the majority of vineyards. This resulted in increased contents of Ca, Mg and K. The intensive P fertilization in the areas provoked very high P concentrations in soil that can be undesirable owing to P leaching and nutrients unbalance. Of the analyzed areas the with 6 years of vine cultivation, experimental area of Embrapa, was the one that it presented smaller alteration in relation to reference area, for majority of the analyzed chemical attributes.