Using community metabolism to define the riverine, transition, and lacustrine zones of a reservoir, Lake Waco, Texas.

Community metabolism of the pelagic region of Lake Waco was measured in different areas in order to define the riverine, transition, and lacustrine zones with a biological indicator. Community metabolism was measured using the production to respiration ratio (P/R). Both production and respiration were measured by oxygen change. Daily and seasonal variation, summer through fall, was great, but general trends over time showed little difference between different parts of the lake. Median P/R ratios were highest closest to the dam at 1.9. This station also showed the greatest variability in P/R, but the least in chlorophyll. The expected transition zone and riverine zone ratios ranged from 0.3 to 3.3. There was no statistical difference between chlorophyll concentrations throughout the reservoir. Due to the drought conditions under which the data was collected, Lake Waco was determined to show more natural lake than reservoir characteristics.