BASAL RESPIRATION AND MICROBIAL POPULATION OF A RED-YELLOW LATOSOL UNDER DIFFERENT HARVESTING SYSTEMS OF SUGARCANE

The objective of this study was to evaluate the basal respiration and microbial population of a red-yellow latosol submitted to burning and mechanical harvesting. The following treatments were studied: manual harvesting of burned sugarcane (BS), mechanical harvesting of 1 st leaf (MH1), mechanical harvesting of 2 nd leaf (MH2), mechanical harvesting of 3 rd leaf (MH3) at depths: 0-5, 5-10, 10-20 cm. The basal respiration was determined by CO 2 capture. The microbial population was estimated by the number of Colony Forming Units (CFU) of bacteria and cultivable fungi. CO 2 release rates ranged from 22 to 35.92 mg Kg-¹CO 2 , BS treatments differed statistically from MH1 treatments, which differed from MH2 and MH3. There were no significant differences for CO 2 release at the depths evaluated. For fungi the CFU number did not differ between BS and MH1, and between MH2 and MH3. The greatest number of CFU was obtained for depth of 0-5 cm 2.5x106g -1 . For depth 0-5 and 10 to 20 did not differ significantly between them and the lowest number of CFU was obtained for the depth of 5-10 cm 1.9x106g -1 .