Quantification and characterization of sedimenting particulate organic matter in a shallow hypereutrophic lake*

Abstract

SUMMARY. Sedimenting seston was collected in May‐November 1976 and 1977 in sedimentation traps anchored 0.5 m above the pelagic sediments of hypereutrophic Wintergreen Lake. Sedimentation rates differed greatly in the two years studied, ranging from 2.7 to 19.3 g m−2 day−1 in 1976 and from 2.6 to 9.5 g m−2 day−1 in 1977. Because of the shallowness of the lake (maximum depth 6.5 m), the quantity and quality of sedimenting particulate organic matter (POM) was closely linked to the production dynamics of the phytoplankton. Chemical analyses indicated that the sedimenting POM was planktonic in origin and, in contrast to that of many deeper lakes, was dominated by protein. Short sedimentation distances coupled with the close proximity of the anaerobic hypolimnion to the photic zone ensured that the majority of sedimenting POM reached the sediments in a relatively undegraded form.

Long‐term changes in the areal hypolimnetic oxygen deficit (AHOD) of Onondaga Lake: Evidence of sediment feedback

“…2C), is rare, if not unique. The downward flux of POC is an acknowledged metric of primary production (Molongoski and Klug 1980;Kelly and Chynoweth 1981), and it is the link connecting metabolism between the trophogenic and tropholytic zones. The abrupt, steplike, decrease in POC df following industry closure has provided a rare opportunity to resolve and characterize the effects on hypolimnetic DO resources.…”

Partitioning whole‐lake denitrification using in situ dinitrogen gas accumulation and intact sediment core experiments

“…The selected NO { 3 -N addition rate reflected typical prestratification concentrations at Lake Fayetteville. The PC addition was derived from the concentrated seston slurry and was intended to mimic a typical rate of organic C sedimentation in a eutrophic reservoir over a 2-week period (Molongoski and Klug 1980). The experimental rate of PC loading to bottles was determined post hoc by filtering 0.5 mL of slurry onto a Whatman GFF filter and analyzing the filter for organic C on a Thermo Flash 2000 Organic Elemental Analyzer.…”

Water-quality models to assess algal community dynamics, water quality, and fish habitat suitability for two agricultural land-use dominated lakes in Minnesota, 2014

“…The sediment release rate of phosphorus can be related to the available phosphorus in the sediments, which, if the available phosphorus was large due to legacy phosphorus loading (Marsden, 1989;James and others, 2015), under favorable conditions, more phosphorus can be released back into the water column. The SOD is the oxygen consumed by organisms in the sediment, so in shallow to moderately deep lakes rich in organic matter (such as eutrophic lakes), SOD can be large (Molongoski and Klug, 1980;Cross and Summerfelt, 1987), whereas in an oligotrophic lake this effect would not be as important. Extinction coefficients are related to light extinction caused by different solids in the water column, such as inorganic suspended solids, organic suspended solids, algal biomass, and macrophyte biomass (Cole and Wells, 2015).…”