Abstract: Seaweed beds play an important role in marine ecosystem, with unique ecosystem services value. We evaluated the importance of specific indices of ecological services of macroalgae in the seaweed beds of the eastern coastal waters of Shenzhen, China. Based on the previous survey of seaweed bed resources, their ecological values were evaluated using the market valuation method, alternative cost method, and contingent value method. The results showed that the importance of the specific indices of ecological services of macroalgae in the seaweed beds of four eastern coastal waters of Shenzhen was in an order of carbon sequestration and oxygen release > biodiversity maintenance > removal of N and P > material production > absorption of heavy metals > scientific research. The mean annual biomass of macroalgae was 10427.42 g·m^-2, the area of seaweed beds was 14.55 hm², and the total resource of macroalgae was 3983.90 t·a^-1. The total value of ecological services was 2.49 billion yuan·a^-1, with a per unit area value of 117 million yuan·hm^-2·a^-1. The ecological services value of macroalgae in the seaweed beds was 714, 587, 553, and 637 million yuan·a^-1 for Xiaomeisha, Qixing Bay, Yangmeikeng-Luzui, and Dongchong-Xichong, respectively, and accounted for 28.67%, 23.58%, 22.19%, and 25.56%. The quantification of the ecological values of macroalgae in the seaweed beds is helpful for protecting seaweed beds, which provides data support for the construction of marine pastures and related economic strategic decisions. Meanwhile, our evaluation method can provide reference for the formulation of the evaluation standard of ecosystem services of seaweed beds in China.

Key words: eastern coastal waters of Shenzhen, seaweed bed, macroalga, ecological services, evaluation