Mangrove leaf litter input and folliage renovation of an estuarine system in southeast Mexico

The patterns of mangrove litter production were studied in Pom-Atasta, a estuarine system linked to Terminos Lagoon, Campeche coast, Mexico. Four sampling sites with contrasting conditions of tidal influence were selected. Ten litter baskets placed randomly in each site for litter fall evaluation, were emptied monthly during an annual cycle (1995-1996). Litter material was classified, dried and weighed. The flowering season for Avicennia germinans was from June through September; Rhizophora mangle had flowers and hypocotyls year round. The most productive site was riverine forest dominated by A. germinans in the area with least tidal influence and hypohaline conditions, low annual salinity variation and lime-clay soils. Average litter production varied between 1.8 and 4.5 g m-2 day-1 and was closely related to regional climatic periods. In October 1995, two hurricans: Roxane and Opal. blew in the region and caused an extraordinary defoliation with liner production between 8 a 12 g m-2 day-1 These figures greatly exceed the amounts registered for mangroves in the Gulf of Mexico, the Caribbean and the Equator. The leaf renewal rate was 129-392 days.