Denitrification in Lake Sediments

The capacity of selected calcareous and non-calcareous lake sediments from Wisconsin to reduce NO3-N gas to N2 gas under anaerobic conditions was examined. Although the individual rates of denitrification varied, all lake sediments examined were able to convert approximately 70% of added NO3-N to N2. In one case, approximately 65% of added NO2-N was also converted to N2. All sediments were able to generate CH4 and when amended with either NO3-N or NO2-N produced N2O as a transient intermediate.