Search results for "INORGANIC CARBON"
showing 2 items of 22 documents
Biogenic Fenton process - A possible mechanism for the mineralization of organic carbon in fresh waters.
2020
To explore the mechanisms that mineralize poorly bioavailable natural organic carbon (OC), we measured the mineralization of OC in two lake waters over long-term experiments (up to 623 days) at different pH and iron (Fe) levels. Both the microbial and photochemical mineralization of OC was higher at pH acidified to 4 than at the ambient pH 5 or an elevated pH 6. During 244 days, microbes mineralized up to 60% of OC in the 10-mu m filtrates of lake water and more than 27% in the 1-mu m filtrates indicating that large-sized microbes/grazers enhance the mineralization of OC. A reactivity continuum model indicated that the acidification stimulated the microbial mineralization of OC especially i…
A stable isotope study of the hydrological and carbon cycle in meromictic lake, Lovojärvi
2012
Lake Lovojärvi, at its deepest point of 17.5 m, is permanently stratified forming two water layers. The mixolimnion (the upper layer, from 0 to 10 m depth) is affected by seasonal changes while the monimolimnion (bottom layer, from 10 to 17.5 m depth) does not mix and is not affected by seasonal changes. As a result, the lake stores large quantities of dissolved inorganic carbon and methane. I used a multiple stable isotope approach to gain insight into the carbon cycle and water balance of Lovojärvi. The δ18O and δ2H profiles reveal that at the 7 m depth in the mixolimnion, there is a sub-surface stream whose isotopic characteristics are similar to surface streams from a nearby mire, sugge…