Final Report IMPACTS OF TROPHIC STATE ON THE COMPOSITION OF ALGAE ASSEMBLAGES OF THE HARPETH RIVER IN MIDDLE TENNESSEE Jefferson G. Lebkuecher Biology Department Austin Peay State University Clarksville, TN
[email protected] Submitted to the Harpeth Conservancy Daniel B. Fitzgerald, Ph.D. Director of Watershed Science and Restoration The Harpeth Conservancy 215 Jamestown Park First Floor Brentwood, TN 37027
[email protected] 615.790.9767 www.harpethriver.org ii TABLE OF CONTENTS Abstract .……………………………………….………..…………………………………………………………………….…....….. 1 Introduction …..…………………………………………………………………………………………………….…….…….…….. 2 Bioassessments using algae ………………………………………………………………………………..…….…………….. 2 Bioassessments using diatoms ……………………………………………………………………………….……………..... 3 Bioassessments using soft algae ……………………………………………………………………………………….…….. 4 Methods and Materials ……………………………………………………………….……………………………………….... 5 The study area: Harpeth River Watershed ……………………………………………………………………….……... 5 Sampling site locations and dates …..……………………………………………………………………………………….. 6 Sampling cobbles to determine periphyton characteristics …………………………..…….…….…..……….. 6 Periphyton pigment concentrations and ash-free dry mass ………………………………………………….…. 7 Composition of soft-algae assemblages ………………………….…….…………….….………………….…….…….. 8 Composition of diatom assemblages …………………………..………………..……………………..……..….….….. 9 Metrics and indices …………………………………………………………………………………………….……….………… 10 Concentrations of total phosphorus and total nitrogen of water samples …………………………….. 11 Reach