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Coral reefs in the US Virgin Islands (USVI) are threatened by multiple human impacts such as coastal development and pollution. In St. John,USVI, watershed development and unpaved roads have been shown toincrease the delivery of sediment and land-based pollutants to sensitive coral reef habitats. Hallock et al. (2003) described a “FORAM Index” (FI),based on the proportion of symbiont-bearing foraminifera. The FI is used asa proxy for water quality in tropical coral reef environments and predicts whether water quality is adequate for reef growth or recovery. The objectives of this study are 1) to examine differences between the FI in coral reefs below areas of watershed development (with abundant unpaved roads) compared to below undeveloped watersheds that are protected within the Virgin Islands National Park, and 2) to examine if the FI changed from 2011 to 2013. Benthic sediment samples (top 1-2 cm) were collected using snorkel and SCUBA in 2010, 2011, and 2013 from three coral reef sites, one below a developed watershed, one below a minimally developed watershed and one from a mangrove area with coral reefs (Hurricane Hole).Samples were wet sieved (63μm), split, and 150-200 Foraminifera were picked and counted. Foraminifera were then identifi ed and classified as symbiont-bearing, opportunistic, or heterotrophic. Finally, the FI was calculated for each site. The FIs at minimally developed sites were greater than at developed sites, indicating better water quality at sites protected by the national park. The FI increased between the years, suggesting a slight improvement in water quality over time, which may be related to the paucity of large storms or the implementation in 2011 of watershed restoration. The FORAM Index can be used as part of regular reef monitoring to track the condition of coral reefs. 

Abstract Bedforms of Thwaites Glacier, West Antarctica both record and affect ice flow, as shown by geophysical data and simple models. Thwaites Glacier flows across the tectonic fabric of the West Antarctic rift system with its bedrock highs and sedimentary basins. Swath radar and seismic surveys of the glacier bed have revealed soft‐sediment flutes 100 m or more high extending 15 km or more across basins downglacier from bedrock highs. Flutes end at prominent hard‐bedded moats on stoss sides of the next topographic highs. We use simple models to show that ice flow against topography increases pressure between ice and till upglacier along the bed over a distance that scales with the topography. In this basal zone of high pressure, ice‐contact water would be excluded, thus increasing basal drag by increasing ice‐till coupling and till flux, removing till to allow bedrock erosion that creates moats. Till carried across highlands would then be deposited in lee‐side positions forming bedforms that prograde downglacier over time, and that remain soft on top through feedbacks that match till‐deformational fluxes from well upglacier of the topography. The bedforms of the part of Thwaites surveyed here are prominent because ice flow has persisted over a long time on this geological setting, not because ice flow is anomalous. Bedform development likely has caused evolution of ice flow over time as till and lubricating water were redistributed, moats were eroded and bedforms grew.