Stream diurnal dissolved oxygen profiles as indicators of in-stream metabolism and disturbance effects: Fort Benning as a case study

We investigated whether two characteristics of stream diurnal dissolved oxygen profiles, the daily amplitude and maximum value of the dissolved oxygen saturation deficit, are useful indicators of stream metabolism and the effects of catchment-scale disturbances. The study was conducted at the U.S. Army's Fort Benning installation where vegetation loss and high rates of erosion from intensely used training areas and unpaved roads have resulted in extensive sedimentation in some streams. Diurnal profiles of dissolved oxygen were measured in 10 second-order streams draining catchments which exhibited a range of disturbance levels. Rates of gross primary production (GPP) and total ecosystem respiration (R) per unit surface area were determined for each stream using the single-station diurnal dissolved oxygen change method with direct measurement of air–water oxygen exchange rates. The daily amplitude of the diurnal dissolved oxygen deficit profile was highly correlated with daily rates of GPP, and multiplying the daily amplitude by average stream depth to account for differences in water volume did not improve the correlation. The daily maximum dissolved oxygen deficit was highly correlated with daily rates of R, and multiplying by average stream depth improved the correlation. In general, these indicators of stream metabolism declined sharply with increasing catchment disturbance level, although the indicators of R showed a more consistent relationship with disturbance level than those of GPP. Our results show that the daily amplitude and maximum value of diurnal dissolved oxygen deficit profiles are good indicators of reach-scale rates of metabolism and the effects of catchment-scale disturbance on these metabolism rates. At Fort Benning, and presumably at other military installations, they are useful tools for evaluating trends in impacts from military training or rates of recovery following restoration activities.

[1]  Gene E. Likens,et al.  Pattern and Process in a Forested Ecosystem , 1980 .

[2]  William H. McDowell,et al.  Inter‐biome comparison of factors controlling stream metabolism , 2001 .

[3]  P. Mulholland,et al.  Catchment disturbance and stream metabolism: patterns in ecosystem respiration and gross primary production along a gradient of upland soil and vegetation disturbance , 2005, Journal of the North American Benthological Society.

[4]  Virginia H. Dale,et al.  Understory vegetation indicators of anthropogenic disturbance in longleaf pine forests at Fort Benning, Georgia, USA , 2002 .

[5]  A. Spacie,et al.  Dissolved oxygen dynamics of streams draining an urbanized and an agricultural catchment , 2003 .

[6]  T. Bott.  CHAPTER 28 – Primary Productivity and Community Respiration , 2007 .

[7]  Alan D. Steinman,et al.  Improvements to the diurnal upstream-downstream dissolved oxygen change technique for determining whole-stream metabolism in small streams , 1998 .

[8]  Gene E. Likens,et al.  Inorganic Nitrogen Losses from a Forested Ecosystem in Responseto Physical, Chemical, Biotic,and Climatic Perturbations , 2002, Ecosystems.

[9]  G. Lamberti,et al.  Methods in stream ecology , 1997 .

[10]  A. Huryn,et al.  EFFECTS OF LAND USE ON STREAM METABOLISM AND ORGANIC MATTER TURNOVER , 1999 .

[11]  J. W. G. Lund,et al.  A Manual on Methods for Measuring Primary Production in Aquatic Environments. , 1970 .

[12]  Kelly O Maloney,et al.  Influence of Catchment-Scale Military Land Use on Stream Physical and Organic Matter Variables in Small Southeastern Plains Catchments (USA) , 2005, Environmental management.

[13]  Wayne T. Swank,et al.  Stream Chemistry Responses to Disturbance , 1988 .

[14]  John B. Erdmann.  Discussion of "Delta Method for Estimating Primary Production, Respiration, and Reaeration in Streams" , 1992 .

[15]  G. Cavalcanti.  Effects of Sediment Deposition on Aboveground Net Primary Productivity, Vegetation Composition, Structure, and Fine Root Dynamics in Riparian Forests , 2004 .

[16]  William M. Lewis,et al.  Uncertainty in the Estimation of Stream Metabolism from Open-Channel Oxygen Concentrations , 1998, Journal of the North American Benthological Society.

[17]  J. Stoddard,et al.  Is Nitrogen Deposition Altering the Nitrogen Status of Northeastern Forests? , 2002 .

[18]  Gene E. Likens,et al.  Climatic Control of Nitrate Loss from Forested Watersheds in the Northeast United States , 1996 .

[19]  R. Rathbun,et al.  Laboratory Studies of Gas Tracers for Reaeration , 1978 .