Atributos químicos do solo e teor foliar de nutrientes em cana-de-açúcar sob diferentes formas de preparo de solo em área de reforma e expansão no Cerrado

Abstract

Since its introduction in Brazil, Sugarcane (Saccharum spp) is known for its importance to the country. Actually, its eminence is due to the energetic source with ethanol production, reducing petrol consume and dependence. Regarding the renewable source of clean energy and its different applications it becomes essential its sustainable production, decreasing the soil till. The scenarios of sugarcane cultivation it is under the strong presence of machines and heavy implements which may cause debilitation of physical, chemical, biological and hydric soil conditions, forcing soil degradation. Facing this, it becomes necessary to implement practices to promote the sustainability of the activity. However the objective of the present work was to verify the influence of different tillage over soil chemical properties and the macro and micronutrients absorptions by the leaves. The trial was set at Jalles Machado Mill and the planting and evaluations were done from January 2009 and July 2010. There were studied two different environment productions being one a sugarcane renovation area and the other a expansion area over pasture. In each one of the areas the experimental design utilized was a randomized blocks with six treatments and four replications adding a total area of 34.650 m2 each area. At the renovation area it was planted the IAC 87-3396 variety and it was set the following tills: desiccation + limestone + plowing + harrow (T1); limestone + subsoiler + plowing (T2); desiccation + limestone + zero till (T3); desiccation + limestone + subsoiler + zero till (T4); ratton destroyer + limestone + subsoiler (T5); ratton destroyer + limestone + plowing + harrow + plowing (T6). Already at the expansion area there were set the following treatments, using the variety CTC -2: desiccation + limestone + harrowing + plowing (T1); limestone + harrowing + plowing (T2); limestone + plowing + harrowing + plowing (T3); desiccation + limestone + zero till (T4); desiccation + limestone + subsoiler (T5) e plowing + limestone + harrowing + plowing (T6). There were evaluated the following soil chemical attributes: pH, H+Al, Al, m%, V%; the organic matter; macronutrients and micronutrients from soil and plant leaves. The analyzed variables were submitted to presuppositions test, variance and Tukey at 1 and 5% of probability. It was conclude that zero till may be beneficial through the cultivation years; the tested tillage had little influence on soil chemical attributes at this first year of evaluations, as well as did not promoted nutrient absorption by the leaves at the reform area. But for the expansion area the different till promoted soil chemical attributes changes and also to the leave s nutrients.