Journal
LIMNOLOGY AND OCEANOGRAPHY
Volume 58, Issue 4, Pages 1259-1270Publisher
WILEY
DOI: 10.4319/lo.2013.58.4.1259
Keywords
-
Categories
Funding
- Estonian Ministry of Education and Research [SF0170011508]
- Estonian Science Foundation [7600, 8189, 9102]
- EU Regional Development Foundation, Environmental Conservation and Environmental Technology R&D Programme project Observatory of Estonian aquatic environment [3.2.0802.11-0043]
- 7th EU Framework Programme, Theme 6 (Environment including Climate Change) project REFRESH (Adaptive strategies to Mitigate the Impacts of Climate Change on European Freshwater Ecosystems) [244121]
- Mobilitas postdoctoral grant [MJD51]
- European Social Fund
Ask authors/readers for more resources
We traced the origin of dissolved organic matter (DOM) in the large, shallow, eutrophic Lake Vortsjarv in Estonia. Allochthonous DOM (Al-DOM) had higher delta C-13 values than autochthonous DOM (Au-DOM). The delta C-13 of inflow DOM varied from -228.2 parts per thousand to -225.4 parts per thousand (mean -226.7 parts per thousand) and in-lake DOM varied from -228.4 parts per thousand to -26.1 parts per thousand (mean -227.2 parts per thousand). Low stable isotope (SI) signatures of Au-DOM were caused by relatively C-13-depleted values of its precursors (mainly phytoplankton) with mean delta C-13 of -28.9 parts per thousand. SI signatures of dissolved inorganic carbon (DIC) in the inflows and in the lake were also relatively low (from -15.1 parts per thousand to -23.28 parts per thousand). SI values of DOM were lower during the active growing season from May to September and higher from October to April, with the corresponding estimated average proportions of Al-DOM 68% and 81%. The proportion of Al-DOM decreased with increasing water temperature, chlorophyll a, and pH and increased with increasing water level and concentration of yellow substances and DIC. The high proportion of Al-DOM in Vortsjarv shows that, even in this highly productive ecosystem, the labile Au-DOM produced is rapidly utilized and degraded by microorganisms and thus makes a relatively small contribution to the instantaneous in-lake DOM pool.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available