Double whammy for important Baltic seaweed

Wherever ecosystems rich in species develop on the rocky shores of the Baltic Sea, the bladder wrack Fucus vesiculosus has provided perfect groundwork. By colonizing pebbles and rocks, it creates habitats for many other species. Other algae grow on the seaweed to be grazed by snails, isopods and amphipods. Crustaceans, mussels and predatory fish as well as many smaller organisms that are important for the Baltic Sea ecosystem thrive in submarineFucus forests. Fucus vesiculosus is one of the main producers of organic matter in the Baltic and plays a crucial role for its biodiversity and biogeochemical cycles. These functions could be lost due to a series of reactions triggered by climate change.

According to a study conducted by marine biologists of GEOMAR Helmholtz Centre for Ocean Research Kiel and Rostock University within the German research network BIOACID (Biological Impacts of Ocean Acidification), eutrophication - that is already known for its negative effects - and rising seawater temperatures could lead to a decline of the bladder wrack in the Baltic Sea. "It is important to consider the effects of a combination of global and local environmental factors on entire ecosystems", Dr. Franziska Julie Werner stresses. The post-doctoral researcher in marine ecology at GEOMAR is main author of two studies published in the magazines Limnology and Oceanography and Oecologia. "Our results also illustrate how important it is to promote a successful eutrophication management in the Baltic Sea - a factor which, unlike rising global temperatures, could be achieved by national commitment."