| Mangroves are considered dominant primary producers in many tropical and subtropical coastlines. In recent years, modeling of primary productivity (PP) and net primary productivity (NPP) in terrestrial ecosystems has been a subject of increasing interest because of the importance of the terrestrial carbon cycle in the global carbon budget and in climate change. Various studies have reported that leaf area index (LAI), litterfall and nutrient dynamics are some essential parameters related to the photosynthetic capacity of the mangrove ecosystems. The overall objective of this research was to determine PP of the red mangrove, Rhizophora mangle, in the Natural Marine Reserve of La Parguera, Puerto Rico, using both field measurements and remote sensing techniques.;Spatial and temporal trends in LAI, litterfall and nutrients exhibited a temporal variation that was mostly influenced by air temperature and salinity. Remineralized nutrients from leaf litter or exogenous nutrient inputs were the driving force for the observed spatial dynamics of primary productivity within these mangrove forests.;The remotely-sensed normalized-difference vegetation index (NDVI) was highly correlated with field-measured mangrove LAI. Accordingly, LAI maps of the study site were derived from IKONOS satellite imagery. LAI derived values were transformed to net primary productivity maps. Spatial variations of the NPP were clearly detected from remotely sensed images and can possibly be used to explain ecological patterns of LAI and leaf fall. |
