Rt. James et al., WATER-QUALITY TRENDS IN LAKE TOHOPEKALIGA, FLORIDA, USA - RESPONSES TO WATERSHED MANAGEMENT, Water resources bulletin, 30(3), 1994, pp. 531-546
Water quality in eutrophic Lake Tohopekaliga, Florida, improved marked
ly from 1982 to 1992 as a result of reductions in phosphorus and nitro
gen loading to the lake. Annual budgets of water, chloride, phosphorus
and nitrogen were constructed for the lake, and indicate it is a sink
for phosphorus and a source for nitrogen. Water column concentrations
of total phosphorus, soluble reactive phosphorus, total nitrogen, dis
solved inorganic nitrogen, and chlorophyll a all declined as external
inputs of nutrients decreased. Water column nitrogen:phosphorus ratios
have increased, suggesting a probable shift from nitrogen- to phospho
rus-limitation. This apparent shift in nutrient limitation status also
is supported by comparisons of the mean Trophic State Indices for pho
sphorus, nitrogen, and chlorophyll a. These improvements in water qual
ity are attributed to the diversion of wastewater treatment plant effl
uent from the lake, and the increased use of wet retention ponds for s
tormwater runoff.