Effect of Fallow Vegetation Materials Representing Different Organoc Matter Quality on Soil P Availability, P-Microbial Biomass, and Soil Microbe Activities in Incubation Study

Abstract

An incubation study on amended forest soil was conducted to investigate the effect of quality of fellow vegetation residue amended into forest soil on related soil phosphorus parameters. Plant residue from five species of secondary forest vegetation, namely: Albizia lebeck, Trichospermum Sp., Macaranga hispida, hromolaena odorata and Ficus subulata were incorporated in a very low-P Oxisol (0,8 ppm Bray-1;pH 5.68 CaC12) and incubated for 125 days. Soil pH, Net soil P mineralization, Soil P Microbial biomass, soil respiration and phosphatase activities were evaluated. The results revealed dynamics of soil pH during incubation with range from ca. 0.2 to 0.9 units, particulary at the first week. Soil P availability, soil microbial biomass, soil respiration and soil phosphatase activities were affected by plant residue quality. Chromolaena resulted in the highest available P in the soil.