Browsing Asiantuntijatarkastetut julkaisut - Refereed publications by Author "Meier, H. E. Markus"

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  • Kuliński, Karol; Rehder, Gregor; Asmala, Eero; Bartosova, Alena; Carstensen, Jacob; Gustafsson, Bo; Hall, Per O. J.; Humborg, Christoph; Jilbert, Tom; Jürgens, Klaus; Meier, H. E. Markus; Müller-Karulis, Bärbel; Naumann, Michael; Olesen, Jørgen E.; Savchuk, Oleg; Schramm, Andreas; Slomp, Caroline P.; Sofiev, Mikhail; Sobek, Anna; Szymczycha, Beata; Undeman, Emma (Copernicus Publ., 2022)
    Earth system dynamics
    Location, specific topography, and hydrographic setting together with climate change and strong anthropogenic pressure are the main factors shaping the biogeochemical functioning and thus also the ecological status of the Baltic Sea. The recent decades have brought significant changes in the Baltic Sea. First, the rising nutrient loads from land in the second half of the 20th century led to eutrophication and spreading of hypoxic and anoxic areas, for which permanent stratification of the water column and limited ventilation of deep-water layers made favourable conditions. Since the 1980s the nutrient loads to the Baltic Sea have been continuously decreasing. This, however, has so far not resulted in significant improvements in oxygen availability in the deep regions, which has revealed a slow response time of the system to the reduction of the land-derived nutrient loads. Responsible for that is the low burial efficiency of phosphorus at anoxic conditions and its remobilization from sediments when conditions change from oxic to anoxic. This results in a stoichiometric excess of phosphorus available for organic-matter production, which promotes the growth of N2-fixing cyanobacteria and in turn supports eutrophication. This assessment reviews the available and published knowledge on the biogeochemical functioning of the Baltic Sea. In its content, the paper covers the aspects related to changes in carbon, nitrogen, and phosphorus (C, N, and P) external loads, their transformations in the coastal zone, changes in organic-matter production (eutrophication) and remineralization (oxygen availability), and the role of sediments in burial and turnover of C, N, and P. In addition to that, this paper focuses also on changes in the marine CO2 system, the structure and functioning of the microbial community, and the role of contaminants for biogeochemical processes. This comprehensive assessment allowed also for identifying knowledge gaps and future research needs in the field of marine biogeochemistry in the Baltic Sea.
  • Reckermann, Marcus; Omstedt, Anders; Soomere, Tarmo; Aigars, Juris; Akhtar, Naveed; Bełdowska, Magdalena; Bełdowski, Jacek; Cronin, Tom; Czub, Michał; Eero, Margit; Hyytiäinen, Kari Petri; Jalkanen, Jukka-Pekka; Kiessling, Anders; Kjellström, Erik; Kuliński, Karol; Larsén, Xiaoli Guo; McCrackin, Michelle; Meier, H. E. Markus; Oberbeckmann, Sonja; Parnell, Kevin; Pons-Seres de Brauwer, Cristian; Poska, Anneli; Saarinen, Jarkko; Szymczycha, Beata; Undeman, Emma; Wörman, Anders; Zorita, Eduardo (Copernicus GmbH, 2022)
    Earth System Dynamics
    Coastal environments, in particular heavily populated semi-enclosed marginal seas and coasts like the Baltic Sea region, are strongly affected by human activities. A multitude of human impacts, including climate change, affect the different compartments of the environment, and these effects interact with each other. As part of the Baltic Earth Assessment Reports (BEAR), we present an inventory and discussion of different human-induced factors and processes affecting the environment of the Baltic Sea region, and their interrelations. Some are naturally occurring and modified by human activities (i.e. climate change, coastal processes, hypoxia, acidification, submarine groundwater discharges, marine ecosystems, non-indigenous species, land use and land cover), some are completely human-induced (i.e. agriculture, aquaculture, fisheries, river regulations, offshore wind farms, shipping, chemical contamination, dumped warfare agents, marine litter and microplastics, tourism, and coastal management), and they are all interrelated to different degrees. We present a general description and analysis of the state of knowledge on these interrelations. Our main insight is that climate change has an overarching, integrating impact on all of the other factors and can be interpreted as a background effect, which has different implications for the other factors. Impacts on the environment and the human sphere can be roughly allocated to anthropogenic drivers such as food production, energy production, transport, industry and economy. The findings from this inventory of available information and analysis of the different factors and their interactions in the Baltic Sea region can largely be transferred to other comparable marginal and coastal seas in the world.