RESIDUAL CONCENTRATION OF COPPER, IRON, MANGANESE AND ZINC IN EUTROPHIC 'LATOSSOLO ROXO’ UNDER DIFFERENT SOIL MANAGEMENTS

Abstract

The removal of micronutrients from soil by grains and burning of cultural remains constitute the main means of soilexhaustion. The correction of soil fertility and the adapted soilmanagement have been the means used to maintain the grainproduction. The soybean, corn, rice and common bean crops were developed in an eutrophic ‘latossolo roxo’, submitted to fourmanagement systems: 1) no-till, 2) deep moldboard plowing, 3)shallow harrow plowing and 4) deep stirring, using a chiseling plower and three level of fertilization: 1) Check (natural soil fertility), 2) Goiás State recommendation and 3) Fertilizers to cover the nutrients extracted by grain exportation. Larger values of the pH were observed in the superficial layer of soil submitted to deep moldboard plowing in relation to no-till, shallow harrow plowing and deep stirring. Uniform distributions of iron, manganese and zinc were observed in areas submitted to deep moldboard plowing. The 40-60 cm layer presented similar concentrations in all types of soil management. Copper tried in the superficial layer and at deepest layers can be explained by the larger concentration of organic matter and origin of the soil. No variation was observed in relation to fertilizers application.

KEY-WORDS: Micronutrients; no till system; cerrado soil.