Microbial Biomass and Soil Respiration Response to Pruning and Fertilization Practices in Coffee-Pine Agroforestry

Abstract

Pruning and fertilization practices plays an important role in coffee plantation, used to maintain soil quality and coffee productivity. However, the impact of pruning and fertilization practices on soil microbial activity under coffee-based agroforestry are poorly understood. The aimed of this study was to analyze the response of soil microbial properties (i.e., soil microbial biomass C (SMBC) and soil respiration rates (SR)) to pruning and fertilization management in coffee-based agroforestry in UB (Universitas Brawijaya) Forest. A split-plot design with eight treatments and three replications were used in this experiment. The main-plot factor consisted of two types of pruning (Pruning and Bending), and the sub-plot factor consisted of four types of fertilization (i.e., no fertilizer (NF), 100% chicken manure (MN), 50% chicken manure + 50% NPK-inorganic (MN+NPK), and 100% NPKinorganic (NPK)). The result showed that there was a significantly different (p<0.05) in the soil microbial biomass C and soil respiration after the application of fertilizer. The addition of chicken manure (MN and MN+NPK treatment) could enhance the soil microbial biomass and soil respiration, compared to the NF treatment under different pruning practices. The level of soil pH in MN were highest and significantly different with NPK treatment, showed that the application of chicken manure had a potential to neutralize the soil acidity. Metabolic quotient (qCO 2 ) showed highest in the NF treatment as compared to the other treatments. The soil respiration had positive correlation (p<0.05) with SMBC, while SMBC had negative correlation (p<0.01) with qCO 2 .