DETAILED COASTAL SEDIMENTARY RECORD OF WATERSHED LAND USE CHANGE SINCE THE EARLY 1900's: CORAL BAY, US VIRGIN ISLANDS

Sediment cores and surface samples collected in Coral Bay, St. John, USVI, indicate an increase of terrigenous (island-derived) sediment input over the last 100 years that is likely a result of anthropogenic activities. Terrigenous sediment loadings calculated for different parts of Coral Bay reflect a dramatic increase over the past century. The majority of terrigenous sediments entering Coral Bay are discharged through two main tributaries (guts) and are deposited in the innermost bay with little being deposited seaward. Data show that terrigenous sediment loadings into Coral Harbor have increased by ~ 5x since about 1930, with the most dramatic increase starting around 1960. Relative terrigenous sediment loadings from each tributary have varied since the mid 1940's likely in response to changes in anthropogenic activities. The dramatic rate increase seen in the Coral Bay data in 1960 through the late 1990's is likely to have had its beginnings in the 1960s from the construction of a major road, which crosses many of the major guts draining the north half of the Coral Bay watershed, altering natural drainage patterns, increasing the area of denuded slopes and providing an erodible surface for runoff. Additionally, all sites show a considerable increase in sedimentation since ~2000, which is likely due to construction of high-end, large-scale houses, villas and condo's since 2000.