Davis, Maxine; Lalor, Gerald C.; Rattray, Robin
Author Affiliation, Ana.
International Centre for Environmental and Nuclear Sciences
Nutrient status of the Black River system, St. Elizabeth, Jamaica
Jamaican Journal of Science and Technology
Date of Publication
The nutrient status of water samples from the Black River watershed with respect to nitrate+nitrite, orthophosphate, silicate and ammonia is reported. Nitrate+nitrite concentrations in the Black River are highest in the upper section of the river and decline downstream. Fertilizer runoff is a likely source of this dissolved inorganic nitrogen. The Elim River, which is polluted by ammonia and orthophosphate in wastewater effluent from the nearby sugar factory and ammonia from an aquaculture operation, is a major contributor to the nutrient load entering the Upper Morass. Below Lacovia, all nutrient levels in the Black River decrease. This may be partially due to the presence of large quantities of water hyacinth, pointing to the importance of preserving this vegetation. On the Broad River the seasonal saline wedge was evident 6.3 km upstream, producing low silicate and inorganic nitrogen in samples collected near the bottom of the river. A relatively high ammonia concentration was observed in samples collected near the bottom of a section of this river. Nutrients in the plume of the Black River are conservatively diluted at least 1.2 km into the saline water of the bay.....