LITTERFALL PRODUCTION IN MANGROVE FORESTS OF THE SÃO FRANCISCO RIVER ESTUARY, SERGIPE STATE, BRAZIL

Abstract

Litterfall production contributes to the flow models and carbon content essential for ecosystem dynamics. The objective of the present study was to assess litterfall production rates in the Costinha mangrove forests, São Francisco River Estuary, Sergipe state, Brazil. To this end, litterfall production in the study area was monitored in five stratified stations (A, B, C, D and E) using the same channels as dividers. Ten (10) 0.25 m² litter collectors, totaling 120 litterbags, were allocated to each forest station for monthly monitoring lasting two years. The collected material was separated into fractions: leaf, flower, fruit, branch and twig, stipule and miscellaneous, and leaves and fruits were separated by species. The average litterfall production was 13.53 ton ha^-1.year^{-1 in the first year and 13.21 ton ha-1}.year^{-1 in the second year, with no statistically significant differences (p>0.05) between the years during the evaluation period. Generally, litterfall production in} fractions presented the following descending order: leaves > branches and twigs > stipules > fruits and propagules > miscellaneous > flowers, with the leaf fractions accounting for 71.46% of the production. The Costinha mangrove forest showed variable litterfall production rates throughout the study period, but there was an increasing trend in leaf fall in warmer seasons.