Green Efficiency Measurement of Seaweed Culture in China under the Double Carbon Target

Seaweed culture is of great significance in giving full play to the function of marine carbon sequestration and strengthening the protection and repair of the marine ecosystem. Its green efficiency measurement can provide China with a means for a global low-carbon economy. From the ecological perspective of net carbon sink, this paper selects three indexes: input, expected output and unexpected output. The total carbon sink and carbon emissions are included in the evaluation index system of green efficiency of seaweed culture in China. The green efficiency of seaweed culture in China from 2008 to 2020 is calculated by the super-SBM model. Through the redundancy rate of input and output, the influencing factors of net carbon sink output of seaweed culture are put forward. According to the empirical calculation results and influencing factors of green efficiency, the countermeasures and suggestions for green seaweed culture in China under the dual-carbon target are put forward. The results showed that: (1) the net carbon sink and green efficiency level of seaweed culture in China showed an overall growth trend, and there was a lot of room for growth in economic and ecological benefits; (2) influenced by index factors and non-index factors such as marine resource economy and planning, there are differences in seaweed culture and green efficiency in the three major sea areas of China; (3) the indexes of green efficiency of seaweed culture in different study areas are different; and (4) the improvement of green efficiency can promote the Chinese seaweed culture industry. Green technology progress effect, structure effect, and input–output scale effect are the main influencing mechanisms of green efficiency of seaweed culture. It is suggested that in the future, we should optimize the structure of seaweed culture, innovate seaweed culture technology, improve carbon sink trading policy and strengthen the training of carbon sink talents. This will accelerate the realization of the goal of green and double carbon seaweed culture and promote the global low-carbon economy.