Atividade microbiana e decomposição de serrapilheira no Semi-árido Paraibano.

Abstract

The selection of plants with a high capacity for recycling nutrients, producing litter, and exploiting a greater volume of soil, making it possible to maintain the conditions of productivity of the edaphic complex, and an important focus that must be given in the conditions of the semi-arid. The present work aimed to verify the decomposition of different organic materials (litter litter) and microbial activity in Luvissolo in the municipality of Patos-PB The experiment was installed in the field, in the period between December/2001 and May/2002, in the CNPA/EMPRAPA area. An experimental design in blocks was used causalized, with 04 repetitions and 08 treatments (little litter of: mesquite, leucena, jurema-preta, neem, monkfish, juazeiro, angico and jucá). These residues were placed in bags of nylon, containing 20g of dry material and buried at a depth of 20.0 cm. Monthly, until the 5th month, a bag was removed from each treatment where the decomposition rate was evaluated by weighing method and, every 15 days, day and night edaphic respiration was determined. THE The methodology used was based on the principle that the CO² released by an area of ​​soil is absorbed by a solution of KOH 0.5 N and titrated with HCl 0.1 N. It was observed that the litter of leucena and jucá showed greater resistance to decomposition, and litter of monkfish was the one that presented, in the studied period, the highest rate of decomposition. THE CO2 production was more intense at night. It is recommended to disclose to the farmers and ranchers the importance of implanting/conserving tree species in the semiarid region, in view of the benefits it will bring to the soil, in terms of fertility, as well as for comfort animal.