Aquatic Ecology and Water Quality of the St. Marks River, Wakulla County, Florida, with Emphasis on the Role of Waterhyacinth: 1989-1995 Studies;Final technical rept

摘要

Long-time Wakulla County residents report that water hyacinth ( Eichhornia crassipes), an invasive, nonnative aquatic plant was introduced into the St. Marks River in the summer of 1972. Ten years later, water hyacinth became abundant and resource managers began to manage this plant with herbicides. Between 1982 and 1988, the water hyacinth population was minimized by conducting small-scale herbicide applications in early spring each year. Fearing pesticides, a local citizens group sought legislative relief to stop the use of herbicides on the river. In 1988, House Bill 1671, Section 25 was passed prohibiting the use of herbicides on the river until a comprehensive ecological investigation was completed by the Florida Department of Natural Resources (now the Florida Department of Environmental Protection, FDEP). This report presents results from an ecological monitoring program conducted from 1989-1995, along with results from special studies that were conducted on the St. Marks River. The objectives were to assess the ecological effects of water hyacinth population dynamics in relation to the hydrological characteristics of the river. The study focused on the section of the river composed of a wide, shallow pool (16.1 ha) immediately south of the St. Marks River head-spring, which was historically conducive to water hyacinth growth. The study findings will be used to formulate a sound aquatic plant management program for the river.