ARS | Publication request: Modeling dissolved oxygen dynamics in blackwater rivers: The importance of site-specific data and carbon flux parameter complexity

Submitted to: North American Benthological Society Bulletin
Publication Type: Abstract Only
Publication Acceptance Date: January 31, 2011
Publication Date: May 21, 2011
Citation: Mehring, A.S., Davie, S.R., Vellidis, G., Bosch, D.D., Pringle, C.M., Lowrance, R.R. 2011. Modeling dissolved oxygen dynamics in blackwater rivers: The importance of site-specific data and carbon flux parameter complexity [abstract]. North American Benthological Society Bulletin.

Technical Abstract: The validity of models predicting parameters of ecosystem health may be limited by the resolution of data available for target river reaches. Here we test the ability of the Environmental Fluid Dynamics Code (EFDC) model to accurately predict dissolved oxygen (DO) concentrations in two reaches of southern Georgia’s Little River, using a long-term dataset including carbon flux parameters of varying complexity. Benthic oxygen demand is estimated from inputs, respiration rates, standing crops and breakdown rates (k) of leaf litter from five common tree species in 2nd- and 5th-order stream reaches. Goodness of fit (observed v. predicted DO) of model output is generated separately for each target reach from three parameterization datasets: (1) the Ogeechee River, and (2) the 2nd-order and (3) 5th-order reaches of the Little River. For each dataset, we examine effects of carbon flux parameters on DO dynamics using: (1) k of any one of five leaf species from litterbag experiments vs. a composite k (representing the reach’s species mixture of litter inputs) vs. detrital standing stock change over time; and (2) total DOC concentration vs. bioavailable fractions.