Scientific Investigations Report 2009–5029
ABSTRACTDuring August and September 2005, dissolved oxygen, temperature, pH, specific conductance, streamflow, and light intensity (LI) were determined continuously at six sites defining five reaches on Meduxnekeag River above and below Houlton, Maine. These data were collected as input for a dual-station whole-stream metabolism model to evaluate primary productivity in the river above and below Houlton. The river receives nutrients and organic matter from tributaries and the Houlton wastewater treatment plant (WWTP). Model output estimated gross and net primary productivity for each reach. Gross primary productivity (GPP) varied in each reach but was similar and positive among the reaches. GPP was correlated to LI in the four reaches above the WWTP but not in the reach below. Net primary productivity (NPP) decreased in each successive downstream reach and was negative in the lowest two reaches. NPP was weakly related to LI in the upper two reaches and either not correlated or negatively correlated in the lower three reaches. Relations among GPP, NPP, and LI indicate that the system is heterotrophic in the downstream reaches. The almost linear decrease in NPP (the increase in metabolism and respiration) indicates a cumulative effect of inputs of nutrients and organic matter from tributaries that drain agricultural land, the town of Houlton, and the discharges from the WWTP. |
For additional information contact: Part or all of this report is presented in Portable Document Format (PDF); the latest version of Adobe Reader or similar software is required to view it. Download the latest version of Adobe Reader, free of charge. |
Goldstein, R.M., Schalk, C.W., and Kempf, J.P., 2009, Primary productivity in Meduxnekeag River, Maine, 2005: U.S. Geological Survey Scientific Investigations Report 2009–5029, 15 p., online only.
Abstract
Introduction
Purpose and Scope
Description of Study Area
Previous Studies
Review of Primary Productivity in Streams
Methods
Data Collection
Stream Hydraulic Data
Continuous Water-Quality Indicators
Light Intensity
Data Analysis
Primary Productivity In Meduxnekeag River, Maine, 2005
Limitations of the Study and Suggestions for Future Investigations
Summary and Conclusions
References Cited