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We identified eight Panamanian watersheds in which conversion from wet tropical forest to pastures differed and assessed the effects of degree of deforestation, and down-estuary transformations, on the suspended particulate matter discharged from the watersheds, entering, traversing through mangrove estuaries, and emerging into coastal waters. Deforested watersheds discharged larger concentrations of suspended particulate matter, with lower % C and N, higher mineral content, and heavier isotopic signatures into fresh reaches of estuaries. Down-estuary, sediment entrainment increased non-organic content of particulates, and watershedderived imprints of deforestation on composition of particulate matter were mostly erased by withinestuary transformations. Isotopic signatures of C, N, and S in particulate matter demonstrated strong land-sea couplings, and indicated that the direction of the coupling was asymmetrical, with terrestrial and estuarine sources delivering particulate materials to coastal waters and sediments. Mangrove estuaries therefore both act as powerful modulators of human activities on land, while also exporting particulate materials to sea.

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A synoptic perspective of reef biogeochemical dynamics and community structure was revealed using new technologies and methods designed to enable high resolution underwater habitat assessment with non-invasive monitoring capabilities and rapid information output. A towed, chemical sensor platform (TETHYS) and a diver-based, benthic imaging system (SCUBA COP) were developed to compare reef architecture and seafloor morphology across centimeter to kilometer spatial scales, and resolve sub-meter variability in ambient water chemistry across 300 km seascapes. Acoustic bathymetry, stereo-optical imaging, in-situ underwater mass spectrometry, and fluorometry data were coupled with precision navigation to enable multi-parameter biogeochemical and structural comparisons of coastal and island coral habitats surrounding Coiba Island, a UNESCO World Heritage site in Pacific Panamá. Baseline chemical data [O 2 , CO 2 , CH 4 , N 2 ]; and digital 3-D reef mosaics were coupled with SCUBA diver transect data, High Definition video, oceanographic time series from a cabled underwater observatory, Landsat and SeaWiFs satellite imagery to create and validate comprehensive, thematic chemical and benthic habitat maps. This integrated approach shows considerable promise for locating, predicting and quantifying natural and anthropogenic environmental stressors affecting the distribution, diversity and health of tropical coral communities.