Trade-Off of Blue Carbon and Edible Use of Farmed Seaweed in China

With the intensification of the greenhouse effect, the development of marine carbon sequestration (blue carbon) cannot be delayed. At present, marine ranches, such as seaweed aquaculture, have become the main way of marine biological carbon sequestration. Part of farmed seaweed used for blue carbon will inevitably lead to the reduction of other economic values, mainly edible value, so the trade-off between ecosystem service values is particularly important. This paper calculates the value of various seaweed ecosystem services, evaluates the trade-offs and synergies between ecosystem services, and balances various service values to maximize the total service value. We selected 5 major species of cultured seaweeds and 6 major seaweed cultivation coastal provinces in China, and used optimization algorithm to evaluate the trade-off of the harvested ratio of each seaweed in each province. The results show that 19.14% of seaweeds for carbon sequestration can create over 127.62 million yuan in carbon sequestration value, reducing 32.38 million tons of CO2 emission per year, and it will increase by an average of 2.88% per year in the next 3 years, creating huge ecological benefits.