Full abstract

Coastal areas are among the most biologically productive aquatic systems worldwide, but face strong and variable anthropogenic pressures. Few studies have, however, addressed the temporal development of coastal ecosystems in an integrated context.

This study represents an assessment of the development over time in 13 coastal ecosystems in the Baltic Sea region during the past two decades. The study covers between two to six trophic levels per system and time-series dating back to the early 1990s. We applied multivariate analyses to assess the temporal development of biological ecosystem components and relate these to potential driving variables associated with changes in climate, hydrology, nutrient status, and fishing pressure.

Our results show that structural change often occurred with similar timing in the assessed coastal systems. Moreover, in 10 of the 13 systems, a directional development of the ecosystem components was observed. The variables representing key ecosystem components generally differed across systems, due to natural differences and limitation to available data. As a result of this, the correlation between the temporal development of the biological components in each area and the driving variables assessed was to some extent area-specific. However, change in nutrient status was a common denominator of the variables most often associated with changes in the assessed systems.

• To the publication: Olsson, J., Tomczak, M. T., Ojaveer, H., Gardmark, A., Poluma¨e, A.,Muller-Karulis, B., Ustups, D., Dinesen, G. E., Peltonen, H., Putnis, I., Szymanek, L., Simm, M., Heikinheimo, O., Gasyukov, P., Axe, P., and Bergstro¨m, L. Temporal development of coastal ecosystems in the BalticSea over the past two decades. – ICES Journal of Marine Science.

Article authors at the Baltic Sea Centre:

• Maciej T. Tomczak
• Bärbel Müller-Karulis