Effects of Nitrogen and Phosphorus Fertilization on Primary Productivity: A Case History of Grayson Lake, Kentucky
Although fertilization has been a common practice to increase fish production in low nutrient lakes and ponds, applicability of the practice in larger reservoirs is questionable. Under the assumption that increased algal production moves up the food web to fish, we fertilized Grayson Lake, Kentucky, surface water with high N to P ratio fertilizer during springs 1994 and 1995. April through July 1994 we added 1 kg P/ha and 22 kg N/ha over a 9-week period to approximately 162 ha of lake surface area. During 1995 we increased loading to 7 kg P/ha with 22 kg N/ha. Weekly photic zone water...