SUMMARY: The sources of sulphide which appeared in the profundal zone of Blelham Tarn (English Lake District) were investigated. In experimental sediment cores, the absence of sulphate in the overlying water resulted in a drastic decrease in the release of sulphide, which suggested that sulphate reduction was a major contributor to the process. The quantity of suphide produced was much less than that of sulphate removed. This, and the inability to detect free sulphide in sediment interstitial water, was attributed to its rapid precipitation as FeS. In the absence of sulphate, production of sulphide would be from organic sources such as protein. Most probable number estimates indicated that the population of bacteria capable of producing sulphide from cysteine was much larger than that of sulphate reducers. Trace additions of S-labelled sulphate, cysteine and methionine were used to determine their turnover time to sulphide. Sulphate was turned over the fastest and methionine the slowest, and the turnover time was always shorter in profundal sediment. Poor recoveries of added label from littoral sediments were thought to be due to adsorption and higher rates of assimilation. Estimates of flux based on concentrations of sulphate and organic sulphur suggested that putrefaction was a more important source of sulphide in the littoral zone but contributed less than sulphate reduction in the profundal sediments.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error