EFEITOS DE BAGAÇO DE CANA-DE-AÇÚCAR E MINHOCAS (Pontoscolex corethrurus) SOBRE A MICROBIOTA DO SOLO (PARAÍBA, BRASIL)

Abstract

In the cemented plots, between July/93 and August/94, in the campus of the Federal University of Paraíba, in João Pessoa (lat 7o 02' 30'' S and long 3o 45' 06' W), experiments were carried out as follows: in the plots A, B and C podzolic soil was put into them and amended with 25kg of sugarcane bagass and added 80 earthworms (A), 10kg of bagass and 80 earthworms (B) and unamended and added 40 earthworms (C). The results showed that the sugarcane bagass improved same soil properties, by raising the pH and Ca++, organic C, S.O.M., and N levels. Microbial biomass (BM), in mg CO2-C.100g-1 of soil and microbial activity (MA), in g.year-1, showed a means: (A) BM= 7.88mg and AM= 1.54g; (B) BM= 10.44mg and AM= 1.59g; (C) BM= 3.29mg and AM= 1.25g. Ratio Cmic : Corg were higher in the plots with greater amount of sugarcane bagass (0.84% in A, 0.64% in B, and 0.33% in C). Earthworms population density (individuals.m-2) was initially 13 in the three plots and increased to 35 in A, 40 in B, and to 30 in C respectively. The results obtained here suggest that 10kg of sugarcane bagass enhanced soil microbial biomass and activity, and the earthworm population assayed.