Soil Microbial Biomass and Diversity Amended with Bagasse Mulch in Tillage and No-tillage Practices in the Sugarcane Plantation

Abstract Biomass residues in plantation farms and process industries still have valuable materials and can be recycled as other materials. Gunung Madu Plantation (GMP) in Lampung Province, Indonesia where this study was observed had used bagasse as mulch 80 tons (wet weight) per hectare. This study observed the effect of tillage and bagasse much on soil microbes in sugarcane plantation. Each treatment was used in conjunction with or without bagasse mulch in a split-plot experimental design. Previous study showed bagasse mulch had increased litter fungal biomass and communities in the soil. However soil microbial community structure has not been comprehensively investigated. Quinone profile method was used to analyze the community structure amended with bagasse mulch in the sugarcane plantation. Quinone profile method reflectively estimated the microbial biomass and the diversity. The no-tillage with bagasse mulch had the highest microbial biomass (1.026 μmol kg-1 dry soil) compare to the no-tillage without bagasse mulch, the conventional tillage with bagasse mulch and the conventional tillage without bagasse mulch. The Diversity index (DQ) and Shannon-Wiener diversity index (H) was also the highest in the no-tillage amended with bagasse mulch. Therefore mulch treatment in combination with no-tillage is an effective residue management of biomass residue to improve soil quality.