Environmental constraints on the input of reactive organic carbon to the Baltic Sea
Reactive DOC can be degraded into CO2 by O2-consuming photochemical and microbial processes, at rates that are significant for the dissolved O2 concentrations of poorly mixed waters and for the water-atmosphere exchange of greenhouse gases. Thus, in the sensitive environment of the Baltic Sea, the fate of DOC has important consequences.
By a combination of field surveys and experiments, we study key aspects of how SWRT and environmental drivers regulate DOC reactivity. The objectives are to: (I) Determine the degree to which SWRT exerts first-order (direct) control of DOC age, quality and reactivity. (II) Investigate interaction effects between SWRT and environmental factors in the regulation of DOC photo- and bio-reactivity. (III) Quantify the effects of contrasting nutrient concentrations, pH and salinity in freshwater and estuarine systems, on short- and long-term biological and photo-chemical DOC reactivity. The project will improve basic understanding of how one of the most important O2consuming processes in the Baltic Sea, i.e. the degradation of DOC, will respond to a changing environment and altered SWRTs.
Co-funded by CEC (2013-2016) and the Formas strong research environment "Managing multiple stressors in the Baltic Sea".
We participated the ASLO Ocean Sciences Meeting 2014 in Honolulu, Hawaii, with the following abstract titles (presenter):
Alves Soares AR, Marchlewska J, Islam S, and Berggren M.: River export of bioavailable nutrients and labile organic carbon: effects on estuarine nutrient stoichiometry and bacterioplankton nutrient limitation
Alves Soares AR, Kritzberg ES, Persson DA, and Berggren M.: Labile organic carbon in river runoff: the importance of carbon sources and water residence times
We have published the following paper in Journal of Plankton Research:
Berggren M, Sponseller RA, Alves Soares AR and Bergström A-K. 2015. Toward an ecologically meaningful view of resource stoichiometry in DOM-dominated aquatic systems. Journal of Plankton Research, advance online access.