Management of stranded eelgrass and macroalgae along the German Baltic coastline

Journal Article
Schernewski, Gerald
Dahlke, Sven
Haller, Inga
Mossbauer, Matthias
Ocean & Coastal Management

Marine vegetation washed ashore recreationally used beaches is a widespread subject of discussion. This paper presents an innovative and cost-saving monitoring method of stranded eelgrass and macroalgae, combined with surveys and a literature review, to provide baseline criteria for recommendations for an advanced beach wrack management. Between May and October 2010 around 4900 t (dry matter) of beach wrack were accumulated in the study area. Accumulation took place on 8.3% of all days. The material is habitat, a nutrient source for beach ecosystems but also a nuisance for a fraction of beach tourists. Seaside resorts rake beaches mechanically almost every day and remove on average 269 kg/m beach wrack mixed with sand during the summer season. This costs up to 38 Euro per meter beach per year. German beach wrack management is a patchwork of local solutions with no general strategy. Beach wrack is either disposed or re-used as fertilizer, compost or soil improver in agriculture. More than 7.8 million Euros were invested in research for improvements and cost reduction in beach wrack management. Costs for beach cleaning are still an economic burden for spa resorts. The legal situation for biomass treatment is a hindering factor for innovation, and an ecosystem approach to management is regarded too expensive. We recommended overcoming current hindrances and throwbacks in beach management by zoning, seasonable limitations, a two-step beach cleaning, and improved environmental education. In terms of scientific research, a more detailed understanding of beach wrack nearshore drifting processes, and the establishment of baseline criteria is necessary.