IMPACTO DE RESÍDUOS ORGÂNICOS DE ABATEDOUROS DE AVES E SUÍNOS NA RESPOSTA DAS CULTURAS E NOS COMPARTIMENTOS DO CARBONO E NITROGÊNIO DO SOLO EM SISTEMA PLANTIO DIRETO

Abstract

The improper disposal of organic waste from poultry and pigs slaughterhouses can promote environmental pollution. The use of waste compost with or without mineral fertilizers in crop rotations in no-tillage system in the Campos Gerais region would be an alternative.. Moreover, it is important to monitor the risks of environmental quality provided by the use of high doses of organic waste applied in soils. Thus, the experiment was conducted using different levels of organic waste (OW) (0, 25, 50, 75, 100% of organic waste) combined with mineral fertilization (MF) (0, 25, 50, 75, 100 %) for a crop rotation during the period of from 2009 to 2012 under no-tillage Soil samples were collected after 5 crop seasons for assessments of carbon (C) pools. Laboratory experiments to evaluate the of C-CO2 emissions and nitrate leaching and mineralization in columns of PVC with undisturbed and loosened soil. At each columns was applied OW doses such as: (0, 0.5, 1, 2, 4, 8 and 16 Mg ha-1). The cumulative yields have not response to the application of MF and OW. The labile OC fraction extracted by permanganate (C-OXP) had a significant increase in response to the combination between FM and RO (50% OW + 50% MF) which was enabled to increase total organic carbon (TOC). The offset between the C-CO2 emissions and TOC retained soil was positive, and demonstrated the potential for C sequestration with increasing doses of OW in the soil. The nitrates (NO3-) leaching of and its nitrification increases as well increase the N content released by OW. The NO3- showed a lower leaching in columns with loosened soil compared to columns with undisturbed soil. There is confirming their variability in soil upturned the importance of the physical state of the soil nitrification and leaching of NO3-. Residue application from poultry and pigs slaughterhouse increased C mineralization and NO3- promoting increases in productivity, quality chemical, physical and biological soil. The control of the processes of nitrification and leaching of NO3- to the use of ROA need to be considered to synchronize applications via N ROA with losses.