Open AccessTracing inputs of terrestrial high molecular weight dissolved organic matter within the Baltic Sea Ecosystem
Author(s) -
Barbara Deutsch,
Vanja Alling,
Christoph Humborg,
Frederike Korth,
Carl Magnus Mörth
Publication year - 2012
Publication title -
biogeosciences discussions
Language(s) - English
Resource type - Journals
ISSN - 1810-6285
DOI - 10.5194/bgd-9-4483-2012
Subject(s) - dissolved organic carbon , terrestrial ecosystem , estuary , environmental science , oceanography , baltic sea , bay , salinity , organic matter , ecosystem , carbon cycle , ecology , geology , biology
To test the hypothesis whether dissolved organic matter (DOM) in a high latitude marginal sea is dominated by terrestrial derived matter 10 stations were sampled along the salinity gradient of the central and northern Baltic Sea and were analyzed for concentrations of dissolved organic carbon as well as δ13C values of high molecular weight DOM. Different end-member-mixing models were applied to quantify the influence of terrestrial DOM and to test for conservative versus non-conservative behavior of the terrestrial dissolved organic matter in the different Baltic Sea basins. The share of terrestrial DOM to the total DOM was calculated for each station, ranging from 43 to 83%. This shows the high influence of terrestrial DOM inputs for the Baltic Sea ecosystem. The data also suggest that terrestrial DOM that reaches the open Baltic Sea is not subject to substantial removal anymore. However compared to riverine DOM concentrations our results indicate that substantial amounts of DOM (>50%) seems to be removed near the coastline during estuarine mixing. A budget approach yielded residence times for terrestrial DOM of 2.3, 2.7, and 4.1 yr for the Bothnian Bay, the Bothnian Sea and the Baltic Proper