Responses to Artificial Fertilization at Grayson Lake, Kentucky

Abstract An artificial fertilization program was conducted at Grayson Lake (612 ha) from 1994 through 1997 in an attempt to increase reservoir productivity and increase populations of largemouth bass Micropterus salmoides in the reservoir. In 1994 and 1995, a 162-ha portion of Grayson Lake was fertilized with a liquid high-nitrogen fertilizer. In 1995, the high-nitrogen fertilizer was supplemented with a small amount of a liquid high-phosphorus fertilizer. The area fertilized in 1996 and 1997 was reduced to a 41-ha embayment originally in the area fertilized in 1994 and 1995, and the fertilizer was changed to a liquid high-phosphorus fertilizer. No major changes in the quantities of soluble reactive phosphorus (SRP), total inorganic nitrogen (TIN), or chlorophyll a occurred in the fertilized portion in 1994 or 1995. Bottom-up effects were detected after application of the high-phosphorus fertilizer in 1996 and 1997. Increases in SRP occurred in the fertilized portion of the reservoir in 1996, but because ...