Determinação do valor de prevenção para cromo em solos do estado de Minas Gerais

Abstract

This paper aims to investigate the values of prevention for Cr in two classes of soils. They selected two state soil classes of moderate clayey (CXbd) from the campus of the Federal University of Lavras. The soils were classified as Oxisol medium texture dystrophic The moderate rain forest stage subperenifólia (LVAd) from the Municipality of Itumirim-MG and Cambisol also Hapludox The species of plants tested were Zea mays and Phaseolus aureus. The treatments consisted of eight doses of Cr (0, 5, 10, 20, 45, 90, 200 and 400 mg kg-1 of dry soil) applied in solution in the form of dichromate K. The effects of treatments on the plants were evaluated by means of shoot height, root length, shoot dry weight, root dry weight. Data were subjected to non-linear models through the STATISTIC 7.0 software. The value of VP estimated in this study was 292 mg kg-1 for CXbd in maize, while the current value recommended by law is 75 mg kg1 . This value indicates the need to review the current legislation and should be used as a starting point for future studies. It can be said that the higher the dose of Cr added in the largest land the Cr content present in the plant. Although the crops absorb Cr in their structures, much of this is still retained soil.