Metabolism of a sub-tropical low gradient black water river

SUMMARY. 1. Single-station diel oxygen curves were used to monitor the oxygen metabolism of the Ogeechee River, a sixth-order blackwater river in the Coastal Plain of southeastern U.S.A., over a period of 4 years. Ecosystem production (P) and respiration (R) were estimated, and P/R ratios calculated to determine the extent of autotrophy characteristic of this type of river. The potential error in oxygen metabolism caused by photo-oxidation of dissolved organic carbon (DOC) in the water was measured and found to be minor. 2. Rates of ecosystem primary production measured were intermediate compared to other rivers, ranging from 0.49 to 13.99g O2m−2 day −1.Primary production rates were highest during the summer when water levels were low. Regression analysis indicated that water depth and light absorption by DOM were significant predictors of primary production in this river. Incident light intensities were not significantly correlated with production rate. 3. Respiration rates were unusually high, varying between 3.70 and 11.5 g O2 m−2 day − 1. System respiration also varied seasonally, but less than primary production. Rates were slightly higher in spring and summer. 4. With one exception, P/R ratios were considerably lower than l throughout the study period, indicating that the Ogeechee River was highly heterotrophic. PIR ratios ranged from 0.09 to 1.3, and averaged 0.25. 5. A carbon budget calculated for this river showed floodplain inputs were 7 times autochthonous production. Organic carbon turnover length was 690 km, considerably longer than has been reported for lower-order rivers.

[1]  P. Brezonik,et al.  Oxygen consumption in humic-colored waters by a photochemical ferrous-ferric catalytic cycle. , 1981, Environmental science & technology.

[2]  R. O'Neill,et al.  Organic carbon spiralling in stream ecosystems , 1982 .

[3]  J. Day,et al.  PRODUCTIVITY AND COMPOSITION OF A BALDCYPRESS-WATER TUPELO SITE AND A BOTTOMLAND HARDWOOD SITE IN A LOUISIANA SWAMP' , 1976 .

[4]  R. Zepp,et al.  Comparison of photochemical behavior of various humic substances in water: II. Photosensitized oxygenations , 1981 .

[5]  Robert C. Petersen,et al.  Developments in Stream Ecosystem Theory , 1985 .

[6]  J. B. Wallace,et al.  Quantification of Wood Habitat in Subtropical Coastal Plain Streams , 1984 .

[7]  G. Minshall.  Autotrophy in Stream Ecosystems , 1978 .

[8]  G. Minshall,et al.  INTERBIOME COMPARISON OF STREAM ECOSYSTEM DYNAMICS , 1983 .

[9]  T. C. Dorris,et al.  PRIMARY PRODUCTIVITY IN A SOUTHERN GREAT PLAINS STREAM1 , 1966 .

[10]  H. Sioli.  Tropical Rivers as Expressions of Their Terrestrial Environments , 1975 .

[11]  J. Day,et al.  PRODUCTIVITY AND NUTRIENT EXPORT STUDIES IN A CYPRESS SWAMP AND LAKE SYSTEM IN LOUISIANA , 1977 .

[12]  F. O. Howard,et al.  The Utilization of Leaf Litter by Stream Detritivores , 1973 .

[13]  C. Hall,et al.  Methods of Assessing Aquatic Primary Productivity , 1975 .

[14]  R. Zepp,et al.  Photosensitized transformations involving electronic energy transfer in natural waters: role of humic substances , 1985 .

[15]  H. Odum.  Primary Production Measurements in Eleven Florida Springs and a Marine Turtle-Grass Community1 , 1957 .

[16]  John C. Wright,et al.  PRODUCTIVITY STUDIES ON THE MADISON RIVER, YELLOWSTONE NATIONAL PARK1 , 1967 .

[17]  Trevor Platt,et al.  Mathematical formulation of the relationship between photosynthesis and light for phytoplankton , 1976 .

[18]  Gene E. Likens,et al.  Energy Flow in Bear Brook, New Hampshire: An Integrative Approach to Stream Ecosystem Metabolism , 1973 .

[19]  Sandra Brown,et al.  Primary Productivity, Decomposition and Consumer Activity in Freshwater Wetlands , 1981 .

[20]  A. Benke,et al.  INVERTEBRATE PRODUCTIVITY IN A SUBTROPICAL BLACKWATER RIVER: THE IMPORTANCE OF HABITAT AND LIFE HISTORY' , 1984 .

[21]  R. Naiman,et al.  Relationships Between Metabolic Parameters and Stream Order in Oregon , 1980 .

[22]  G. Minshall,et al.  The River Continuum Concept , 1980 .

[23]  D. E. Busch,et al.  Metabolism of a desert stream , 1981 .

[24]  R. W. Edwardś,et al.  The effects of plants on river conditions. I. Summer crops and estimates of net productivity of macrophytes in a chalk stream. , 1960 .

[25]  Charles A. S. Hall,et al.  Migration and Metabolism in a Temperate Stream Ecosystem , 1972 .

[26]  Mahlon G. Kelly,et al.  Light and the annual variation of oxygen‐ and carbon‐based measurements of productivity in a macrophyte‐dominated river1 , 1983 .

[27]  R. Naiman.  The Annual Pattern and Spatial Distribution of Aquatic Oxygen Metabolism in Boreal Forest Watersheds , 1983 .

[28]  Patrick J. Mulholland,et al.  Organic Carbon Flow in a Swamp‐Stream Ecosystem , 1981 .

[29]  N. A. Thomas,et al.  A METHOD FOR MEASURING PRIMARY PRODUCTION BY STREAM BENTHOS , 1966 .

[30]  W. McDiffett,et al.  An Estimate of Primary Productivity in a Pennsylvania Trout Stream Using a Diurnal Oxygen Curve Technique , 1972 .

[31]  Howard T. Odum,et al.  Trophic Structure and Productivity of Silver Springs, Florida , 1957 .