The invasive kelp Undaria pinnatifida: a prominent Asian food source spreading in European waters

• Applicant: Professor Dr. Kai Bischof
• Subject Area: Ecology and Biodiversity of Plants and Ecosystems
• Term: from 2015 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 269232491

The Asian kelp Undaria pinnatifida represents a seaweed species, which is extensively cultivated as food source in Chinese coastal waters and plays an important role in human nutrition in China and Japan ("wakame" in Japan, "qundaicai" in Chinese). Undaria is usually raised in mariculture facilities, where environmental perturbation and potentially overstocking might reduce the annual yield. At the same time, outside its native distributional range U. pinnatifida represents a rapidly spreading invasive species, with the potential to outcompete the respective native marine flora. It´s northern distributional limit in European waters is currently at the Dutch coastline and a further spread into the German Bight is to be expected soon. By the cooperation of a Chinese and German research team, which are both renowned in the field of seaweed biology, new insights will be gained on this species of global significance: We will experimentally explore Undaria´s responses to changing environmental parameters (temperature, radiation and nutrients) and use this information to predict its capacity for future bioinvasion in European waters. In parallel this information will be implemented to improve aquaculture techniques in its native range. We will conduct coordinated experiments in the laboratories in Qingdao and Bremen studying housekeeping ecophysiological processes like photosynthesis, growth, reproduction on specimens from the Qingdao and the northernmost European population of Undaria. We will study the effect of environmental changes on important physiological/biochemical parameters like pigment and fatty acid composition, antioxidative potential, phlorotannin synthesis. In this study we will include all different life-history stages of Undaria. We will furthermore compare the genetic identity of the respective population at both sites applying state-of-the-art techniques in population genetics. Conclusively we will gain new insights into the mechanisms of range expansion, which at the same time will allow for better protection measures against the invader in European waters and potentially improve yield and allow for a more sustainable cultivation (i.e. by less fertilizer release) along the coast of China.

• DFG Programme: Research Grants
• International Connection: China
• Cooperation Partner: Professor Dr. Shaojun Pang