Preliminary studies on phosphate levels in precipitation in the USVI due to Sahara dust

The 2000 summer season has been a severe season for the number of air-borne particles in the Caribbean. Increases in dust levels in the atmosphere due to the desertification in Africa ("Sahara Dust") have created a near constant haze over the United States Virgin Islands. In addition, recent studies on ground and ocean water in the USVI have indicated an increase in non-point source phosphate pollution that cannot be directly linked to agricultural or industrial sources. The result of increases in phosphate levels has been a phytoplankton bloom in the coastal waters. While this phytoplankton bloom has increased the number of filter feeding fishes of the class Osteichthyes and members of Chondrichthyes, such as rays and sharks, it is of concern to the coral reefs which can get buried under layers of plankton and algae, blocking light and killing corals.

New studies begun at the University of the Virgin Islands are monitoring and comparing the levels of atmospheric dust and the levels of phosphates in the ground water. One current proposed hypothesis is that long-range transport of phosphate laden aerosols from areas in Northern Africa are contributing to the phosphate levels in coastal waters. Current student research is focused on collecting samples of precipitation, ground water and coastal ocean water to determine phosphate levels and comparing against levels of dust collected in atmospheric samples. All data submitted is preliminary and for the 2000 season only. Later studies will target direct impacts on the coastal environments and a comparison of dust particulates with various areas of the Sahara to attempt to determine locations of sources.