Environmental changes, such as ocean acidification and eutrophication, have created threats to kelp mariculture. In this study, the growth, photosynthesis, respiration and nutrient composition of Saccharina japonica were evaluated at different levels of pCO 2 (400 and 800 µL L –1) and nutrients (nutrient-enriched and non-enriched seawater). Elevated pCO 2 decreased the relative growth rate (RGR), net photosynthetic rate and contents of tissue carbon and tissue nitrogen under non-enriched nutrient conditions, but it had no significant effect on these parameters under nutrient-enriched conditions. The dark respiration rate was positively affected by elevated pCO 2 regardless of the nutrient conditions. However, the C:N was unaffected by elevated pCO 2 at both nutrient levels. These results implied that ocean acidification could reduce the production and nutrient contents in the tissues of S. japonica, which was associated with nutrient conditions.
The copyright to this article, including any graphic elements therein (e.g. illustrations, charts, moving images), is hereby assigned for good and valuable consideration to the editorial office of Journal of Ocean University of China, Science Press and Springer effective if and when the article is accepted for publication and to the extent assignable if assignability is restricted for by applicable law or regulations (e.g. for U.S. government or crown employees).