To access, purchase, authenticate, or subscribe to the full-text of this article, please visit this link: http://dx.doi.org/10.1007/s13280-017-0930-x Byline: Tobias Tamelander (1), Kristian Spilling (2), Monica Winder (3) Keywords: Acidification; Baltic Sea; Climate warming; Eutrophication; Organic matter export; Pelagic food web Abstract: The impact of environmental change and anthropogenic stressors on coastal marine systems will strongly depend on changes in the magnitude and composition of organic matter exported from the water column to the seafloor. Knowledge of vertical export in the Baltic Sea is synthesised to illustrate how organic matter deposition will respond to climate warming, climate-related changes in freshwater runoff, and ocean acidification. Pelagic heterotrophic processes are suggested to become more important in a future warmer climate, with negative feedbacks to organic matter deposition to the seafloor. This is an important step towards improved oxygen conditions in the near-bottom layer that will reduce the release of inorganic nutrients from the sediment and hence counteract further eutrophication. The evaluation of these processes in ecosystem models, validated by field observations, will significantly advance the understanding of the system's response to environmental change and will improve the use of such models in management of coastal areas. Author Affiliation: (1) Tv?rminne Zoological Station, University of Helsinki, 10900, Hanko, Finland (2) Marine Research Centre, Finnish Environment Institute, P.O. Box 140, 00251, Helsinki, Finland (3) Department of Ecology, Environment and Plant Sciences, Stockholm University, 10691, Stockholm, Sweden Article History: Registration Date: 09/06/2017 Received Date: 19/12/2016 Accepted Date: 09/06/2017 Online Date: 24/06/2017 Article note: Electronic supplementary material The online version of this article (doi: 10.1007/s13280-017-0930-x) contains supplementary material, which is available to authorized users.