%0 Journal Article
%T Spatial variability of mangrove primary productivity in the neotropics
%A Andr¨¦ Scarlate Rovai
%A Edward Casta£¿eda©\Moya
%A Rafaela de Albuquerque Ribeiro
%A Robert R. Twilley
%J Ecosphere - Wiley Online Library
%D 2019
%R https://doi.org/10.1002/ecs2.2841
%X Mangroves are considered one of the most productive ecosystems in the world with significant contributions as carbon sinks in the biosphere. Yet few attempts have been made to assess global patterns in mangrove net primary productivity, except for a few assumptions relating litterfall rates to variation in latitude. We combined geophysical and climatic variables to predict mangrove litterfall rates at continental scale. On a per©\area basis, carbon flux in litterfall in the neotropics is estimated at 5 MgC¡¤ha£¿1¡¤yr£¿1, between 20% and 50% higher than previous estimates. Annual carbon fixed in mangrove litterfall in the neotropics is estimated at 11.5 TgC, which suggests that current global litterfall estimates extrapolated from mean reference values may have been underestimated by at least 5%. About 5.8 TgC of this total carbon fixed in the neotropics is exported to estuaries and coastal oceans, which is nearly 30% of global carbon export by tides. We provide the first attempt to quantify and map the spatial variability of carbon fixed in litterfall in mangrove forests at continental scale in response to geophysical and climatic environmental drivers. Our results strengthen the global carbon budget for coastal wetlands, providing blue carbon scientists and coastal policy makers with a more accurate representation of the potential of mangroves to offset carbon dioxide emissions. Mangrove forests have global distribution of 81,848 km2 (Hamilton and Casey 2016), which is a fraction of the total extent of tropical forests (Giri et al. 2011). However, these coastal forested wetlands are among the most productive ecosystems in the world, playing a major role as sinks in the global carbon (C) cycle (Twilley et al. 1992, Bouillon et al. 2008). Global patterns of mangrove net primary productivity have been associated with variation in coastal geomorphology (relative contribution of river discharge, tidal flushing, and wave energy) and climatic regimes (temperature, precipitation, and evapotranspiration; Lugo and Snedaker 1974, Thom 1982, Twilley 1995). In general, mangroves occurring in coastal morphologies with higher temperatures, tidal range, and riverine inputs (freshwater and nutrient discharge) are more productive than mangroves exposed to harsh environments (e.g., low temperatures, seasonal droughts, and hypersalinity; Fosberg 1961, Pool et al. 1975, Twilley et al. 1986, Schaeffer©\Novelli et al. 1990). Net primary productivity also varies across different ecological types of mangroves as a function of hydroperiod (flooding frequency, duration, and depth;
%U https://esajournals.onlinelibrary.wiley.com/doi/full/10.1002/ecs2.2841