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-A study of heavy metals in estuarine sediments and foraminifera1 tests along with foraminifera1 distributions from Southampton Water indicates that: a) heavy metals have a marked effect upon foraminiferid distribution. Some species are able to tolerate pollution and their relative abundance increases at discharge points, whereas other species develop test deformities. Investigation of cores show that no deformed specimens exist within sediments prior to the introduction of pollution. b) deformed specimens contain higher levels of elements such as Cu and Zn than non-deformed specimens. This indicates that heavy metals may be responsible for the abnormalities within foraminiferid tests. Culture experiments support this hypothesis. Specimens of Ammonia beccarii (Linnk) developed abnormal chambers over a period of 12 weeks within a culture medium containing 10-20ppb of Cu.

The health of the Chesapeake Bay ecosystem has been declining for several decades due to high levels of nutrients and sediments largely tied to agricultural production systems. Therefore, monitoring of agricultural water use and hydrologic connections between crop lands and Bay tributaries has received increasing attention. Remote sensing retrievals of actual evapotranspiration (ET) can provide valuable information in support of these hydrologic modeling efforts, spatially and temporally describing consumptive water use by crops and natural vegetation and quantifying response to expansion of irrigated area occurring with Bay watershed. In this study, a multisensor satellite data fusion methodology, combined with a multiscale ET retrieval algorithm, was applied over the Choptank River watershed located within the Lower Chesapeake Bay region on the Eastern Shore of Maryland, USA to produce daily 30 m resolution ET maps. ET estimates directly retrieved on Landsat satellite overpass dates have high accuracy with relative error (RE) of 9%, as evaluated using flux tower measurements. The fused daily ET time series have reasonable errors of 18% at the daily time step ‐ an improvement from 27% errors using standard Landsat‐only interpolation techniques. Annual water consumption by different land cover types was assessed, showing reasonable distributions of water use with cover class. Seasonal patterns in modeled crop transpiration and soil evaporation for dominant crop types were analyzed, and agree well with crop phenology at field scale. Additionally, effects of irrigation occurring during a period of rainfall shortage were captured by the fusion program. These results suggest that the ET fusion system will have utility for water management at field and regional scales over the Eastern Shore. Further efforts are underway to integrate these detailed water use data sets into watershed‐scale hydrologic models to improve assessments of water quality and inform best management practices to reduce nutrient and sediment loads to the Chesapeake Bay.

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