Residence Time and Release of Carbon and Nitrogen from Litter in Caatinga

Abstract

This study aimed to evaluate decomposition and release of C and of N from the litter of forest Caatinga species in the humification phase, as well as to estimate the residence time of C and N. Litter decomposition of the species was evaluated in 2014/2015 in the municipality of Floresta, Pernambuco, Brazil, using a method of the litter bags at 270; 300; 330; and 360 day. Litter from species of the Fabaceae family presented different decomposition groups, suggesting that decomposition was more influenced by the C/N ratio than N concentration only. The N release was 6.25% greater than the release of C. C will remain in the litter for more time, while N will be almost totally released in approximately 1.14 years. The species litter decomposition were shared, suggesting that the nutrients cycling is fundamental in the preservation of the Caatinga, mainly due to the longer residence time of C.

Keywords:
Dry Tropical forest; Forest nutrition; N cycling; C/N Ratio; Litter humification