The Brazilian potential in the production of electricity from burning bagasse, cane sugar signals to an environmental concern: the large production of waste. The São Paulo industries, especially in the production of alcohol, sugar and citrus juice, are the largest generators of waste ash from bagasse cane sugar (RCC). Of varied composition, rich in macro and micro nutrients and toxic metals in lower concentrations, the RCC has been applied to the soil, without any criteria supported by scientific and environmental law. On the other hand, some studies have been conducted to evaluate only the general characteristics of the RCC and their application effects on attributes of soil fertility and crop development. Knowing the essential nature of biological components to regulate the transformation and accumulation of nutrients, as well as the maintenance of soil organic matter (SOM) for the carbon cycle (C) in the land, this work have hypothesized that the application of RCC in the soil affects the population of microorganisms and biological attributes of the soil, changing the compartments of SOM by moving the C and nitrogen (N). Thus, this study aims: 1) evaluate the effect of different doses of RCC on the attributes and biological compartments of SOM in Alfissol and 2) assess the potential leaching of nitrate and dissolved C in soils of different textures submitted to the application of different doses of RCC. For this, the study will consist of two steps: 1) installation of a field experiment with application rates (0, 5, 10, 20 and 40 t ha-1) of RCC with and without incorporation into Alfissol under cultivation citrus, valued at two periods (wet and dry) during the agricultural years 2012/2013 and 2013/2014, at depths of 0 to 0.05 0.05 to 0.10 m in my first year and 0 to 0.05 ; 0.05 to 0.10 and 0.10-0.20 m in the second year for space 1 (not embedded) and space 2 (embedded) at depths of 0 to 0.15 0.15 to 0 I , 30 m, b) application of the same doses in soil columns with different textures and structures preserved. The designs will be used: a randomized block design for field experiment and for the completely randomized experiment in soil columns with structure preserved. In the field experiment will be evaluated and biological attributes of SOM fractions. In the experiment in soil columns, will be assessed the movement of C and N throughout the soil profile and levels of C and N in the soil leachate. With this, it is expected that this work can contribute to the advancement of scientific knowledge in the application of RCC on the biological attributes of soil and SOM compartments as well as aid in the construction rules of agronomic parameters, environmental, social and economic regarding the correct disposal of RCC in agricultural soils.
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