Limnology of Lago Loiza, Puerto Rico

摘要

The principal chemical, physical and biological characteristics of Lago Loiza, Puerto Rico, and its main tributaries were studied from 1973-74. The lake supplies an average of 300,000 cubic meters per day of water to metropolitan San Juan. Flows from Rio Grande de Loiza and Rio Gurabo contribute 83.0 percent of the water, 67.4 percent of the nitrogen, and 65.7 percent of the phosphorus to the lake. About 31 percent of the nitrogen and 45 percent of the phosphorus were retained in the lake, which has a mean flushing rate of 19 times per year. The lake's capacity declines at a rate of about 1.9 percent per year and is about 14.9 million cubic meters. Lago Loiza is a hypereutrophic lake, with an average total nitrogen concentration of 1.7 milligrams per liter and 0.33 milligrams per liter of total phosphorus.