The areal hypolimnetic oxygen deficit: An empirical test of the model1

Abstract

The areal hypolimnetic oxygen deficit (AHOD) model wa; tested by examining the relationship between rates of hypolimnetic oxygen depletion ant! three measures of lake trophic status. Measurements of AHOD were positively correlated with the measured total phosphorus concentration and with annual 14C pelagic primary pro(luction and inversely correlated with mean summer Secchi depth. Because each of the correlations between AIIOD and trophic status explained ~45% of the observed variation in A HOD values, other factors must also influence the AHOD of a lake. Significant amounts of the residual variation were cxplained by including the mean depth of the lake and meal hypolimnetic temperature as additional independent variables in a multiple regression ar alysis. A lake with a thicker OI warmer hypolimnion had a higher AHOD than a lake with a shallow or colder hypolimnion. The AIIOD model was developed to eliminate the influence o Flake morphometry on interlakc comparisons of hypolimnetic oxygen depletion, but it does nc t do this and a new model must be developed.

In situ pCO2 and O2 measurements in a lake during turnover and stratification: Observations and modeling

“…With further solar heating, the water column becomes thermally stratified, isolating the bottom water from the atmosphere until turnover occurs again, which is usually in the fall for dimictic lakes. The duration and magnitude of ice cover, turnover, and stratification can dramatically influence the concentrations of biogeochemical species both seasonally and interannually (e.g., Cornett and Rigler 1980;Effler and Perkins 1987;Livingstone 1993;Ste-1 Corresponding author (mdegrand@selway.umt.edu).…”

Relationship between areal hypolimnetic oxygen depletion rate and the trophic state of five lakes in northern Poland

“…The role of phosphorus in the TSI(TP)-AHOD relationship has also been confirmed, as did Cornett and Rigler (1980). The relationship between these two variables indicates that it can only explain about 47% of the observed AHOD variability.…”

“…In spite of this, AHOD is not completely independent of the influence of the hypolimnion depth on the rate of oxygen depletion in this layer during the summer stratification period. The lakes with deeper hypolimnion layers provide a longer sedimentation pathway, which creates favorable conditions for complete oxidation of matter undergoing sedimentation (Charlton 1980;Cornett and Rigler 1980).…”

“…However, later research has shown that biological production explains less than fifty percent of the differences in the rate of areal hypolimnetic oxygen depletion (AHOD) Rigler 1979, 1980;Rutherford 1982). This is the result of the oversight of the role of the hypolimnion temperature, which affects decomposition rate of microbiologic matter turning into sediment (Charlton 1980;Rosa and Burns 1987), as well as the oversight of the role of the hypolimnion thickness, which affects the effectiveness of oxidation -a process that intensifies with increasing hypolimnion thickness (Charlton 1980;Cornett and Rigler 1980).…”

The Oxygen Deficit in Jurumirim Reservoir(Paranapanema River, Sao Paulo, Brazil).

“…During sedimentation to deeper region, a degradation of organic matter occurs and induces an oxygen consumption and deficit. In this way, oxygen deficit was related with seston concentration in epilimnetic zone and Secchi disk transparency (LASENBY, 1975), with phosphorus load (WELCH and PERKINS, 1979), also with pelagic phytoplankton production (CORNETT and RIGLER, 1980) highly stable stratification due to the density gradients (HENRY, in press a). The low oxygen content (but higher than 2 mg• 1-1) in water near the bottom had no effect on aquatic organisms .…”