Efeito da compactação do solo na produtividade da cultura da soja (Glycine max L.)

Abstract

The use of techniques aiming soil decompression have been increasing year after year in a planet where food demand is greater every day. In this sense, Brazil have been standing out as one of the main producers in order to meet this increasing demand. Soybean is the main crop and it is among the biggest responsible factors behind economically success of the Brazilian agribusiness. Aiming at increasing production of this important crop, soil decompression techniques have been used constantly. Soil compaction occurs due to the crop-livestock integration, intensification of crops, use of large and heavy machines and agricultural operations with inadequate soil moisture level. The sum of these factors results in an increase in soil density, which restricts water infiltration and storage, leading to flooding, and limiting root development. By promoting soil decompression either through biological or mechanical methods, soil physical conditions become more suitable for crop development what increases soil water infiltration and storage root distribution, increasing the plant’s ability to tolerate periods of water stress. In the test in question, a quadricycle was used wich counted on the measurement of soil compaction through the automated system for measurement. Based on this information, scarification management was performed in area that presented high resistance to soil penetration and scarified an area that presented low resistance to penetration. It was possible to observe that this management brought a 3.2% increase of grain yield of the area of high resistance to penetration and of 12.3% in the area of low resistance to penetration, but without statistical difference. When observing the effect of the scarification in each zone of resistance to different soil penetration, the most positive yield effect in the zone of low resistance to penetration is due to the preferential water flow of the area as well as a larger area of water abstraction, concluding that for a site-specific scarification, the mapping of accumulated water flow to the soil penetration resistance mapping must be linked to perform a really efficient work.