No changes in contributions of echinoderms to the carbon budgets in shelf seas of China over the past five decades

The contribution over the past five decades of echinoderms to the regional carbon cycle of shelf sea areas in China, as well as the changes in calcium carbonate (CaCO₃)/calcium carbonate carbon (CaCO₃-C) standing stocks and production rates, was investigated using meta-analysis. We report results for water depths of <200m in the Bohai Sea, Yellow Sea, and East China Sea. The results show that the average annual standing stock over the past five decades was 2.61MT CaCO₃ (0.31MT CaCO₃-C as inorganic carbon) and the production rate was 1.07MTyr^-1 (0.13MTyr^-1 CaCO₃-C as inorganic carbon). All CaCO₃ standing stocks, CaCO₃ production rates, echinoderm biomasses, and total macrobenthos biomasses showed no significant linear decline, but there was a significant decline for the biomass ratio of echinoderms to total macrobenthic biomass since the 1950s. However, there remain no convincing evidences to explain this due to a lack of environmental data. We suggest that studies on the responses of echinoderms to intense anthropogenic activities and climate change should concentrate on their roles in carbon budgets and macrobenthos community stability.