Litterfall of tropical forested wetlands of Veracruz in the coastal floodplains of the Gulf of Mexico

Canopy productivity of five seasonally flooded forests in the central area of the Gulf of Mexico was estimated by measuring the litterfall. Productivity was estimated on a monthly basis from November 2005 to October 2006, and values ranged between 9 and 15 t ha−1 yr−1. A total of 57 plant species were recorded based on the litter collected. The dominant species (Pachira aquatica, Annona glabra, Hippocratea celastroides and Dalbergia brownei) were the principal litterfall producers. The contribution of two life forms was assessed: trees (including trees, shrubs and palms) and lianas (climbers, lianas and creepers). Lianas were found to be extremely productive and represented between 8 and 62% of the total litterfall at the sampled locations. Leaves contributed most to the litter, followed by branches and reproductive structures. Fruit and seed fall coincided with the rainy season, and accounted for 50–90% of the production and shedding during the flooded season. Species that released seeds during this time had their seeds dispersed by water. Flower production occurred during the dry season (March–June). Species richness did not explain litterfall productivity. The litterfall productivity of these forests is similar to that of mangrove ecosystems.

► Mexican seasonally flooded forests showed a litterfall between 9 and 15 t ha−1 yr−1.
► The dominant species were the principal litterfall producers (i.e. trees P. aquatica, A. glabra) and lianas (H. celastroides and D. brownei).
► The most productive flooded wetlands were the ones in which water level decreased for a few months, but these were not necessarily the most diverse.
► Flowering occurred during the dry season (March to June) and fruit–seed fall coincided with the rainy season (July to October).
► The dominant trees and lianas require flood periods to disperse their seeds and to maintain their litterfall productivity.