Deposição e composição química de serrapilheira em um bosque de sabiá

Abstract

This research aimed to evaluate the deposition and chemical composition of the components of the existing and deposited litter in a sabiá (Mimosa caesalpiniifolia Benth) canopy. The experiment was carried out from August 2006 to July 2007. The evaluation of the existing and deposited litter was performed every 28 days using 20 squares with 1m2 randomly allocated and new areas were chosen for each evaluation. The canopy showed plants with an average diameter of 26.8 cm at breast height. Monthly deposition of organic matter of leaves and branches during the experimental period was 15,167 kg and 3,373 kg/ha, respectively, and it increased during the highest precipitation period, in a 0.30 relationship with the accumulation, indicating higher accumulation than deposition. Leaf proportion was 87% of the total litter, with means of 2.9% of nitrogen and 0.17% of phosphorus. The carbon/nitrogen ratio of leaves was below 30, while carbon/nitrogen ratio of the branches ranged from 30 to 40, proving a better quality for leaves. During the experimental period, deposition of nitrogen through litter was approximately 462 kg/ha and 30 kg/ha for phosphorus. Litter deposition is essential for maintenance of soil fertility in a sabiá canopy and it contributes for conservation and sustainability of the canopy. © 2010 Sociedade Brasileira de Zootecnia.