Qualidade física do neossolo quartzarênico sob manejo de aplicação de cinza vegetal em pastagem em recuperação no cerrado mato-grossense

Abstract

The ash from the burning of wood has the potential to be used as physical conditioning of the soil, changing its quality and physical characteristics. In the study of soil physical quality, the characterization of indicators and indexes related to physical properties is paramount. Thus, the application of wood ash can be an alternative to the supply of organic material in the soil, as much in the chemical increment, because it is rich in essential nutrients the plants, as in the possible influence that can confer the physical quality of the soil. In this context, the objective was to study the influence of the wood ash and forms of application (incorporated with light and non-incorporated grid) in the physical quality of entisols quartzipsamments in recovering Marandu grass pasture. The experiment was conducted in the field at the Mato Grosso do Sul Cotton Institute (IMAmt), located in the municipality of Rondonópolis-MT located geographically at latitude 16º 33 'south; longitude 54º 37 'west and altitude of 314 m The experimental design was in randomized blocks with plot plots in factorial scheme 6x2, corresponding to six doses of wood ash (0, 3, 9, 12 and 15 t ha-1 ) and two forms of application (incorporated with light grid and not incorporated), with four repetitions. The ash was applied manually to the soil surface. Soil samples with deformed and undisturbed structure were collected in the 0-0.20 m layers and 0.20-0.40 m depth within the useful portion of each treatment. The soil physical properties, such as particle size, particle density for soil characterization, and soil bulk density, total porosity, macroporosity, microporosity, soil water retention curve and S. index were evaluated. Results were submitted to analysis of variance and when significant the qualitative variables (incorporation forms) to the Tukey test and the quantitative variables (doses of wood ash) the regression analysis, both until the level of significance of 5% of probability of error. The application of the wood ash in the two years of study did not affect the physical quality of the soil, maintaining its S indexes, as very good physical quality for all the doses of wood ash and application management. In the first year of study the wood ash decreased the density of the soil in the layer (0-0,20 m), being the macroporosity and microporosity consequently influenced by the wood ash, obtaining beneficial effects as the increase of the doses.