Evaluation of coastal wetland ecosystem services based on modified choice experimental model: A case study of mangrove wetland in Beibu Gulf, Guangxi

Abstract

The evaluation of the service value of coastal wetland ecosystem is of great significance for the scientific development and effective utilization of coastal wetland resources. It has been proved that the addition of attribute cut-offs in the choice experiment (CE) evaluation framework improves the validity of evaluation results. However, whether this improvement is due to the improvement of the questionnaire or the improvement of the utility equation cannot be distinguished with this framework. In this study, the modified selection model with cut-off is used to assess the two key elements of the modified selection model that differ from the traditional model. These are the CE questionnaire that leads to cut-off and the CE utility equation that incorporates cut-off. Each element pair is analyzed separately. Both are utilized to evaluate the impact of the validity of the results, and quantitatively evaluate the service value of the mangrove wetland ecosystem in the Beibu Gulf region, Guangxi, China. The results showed that: In 2021, the total value of mangrove wetland ecosystem services in the Beibu Gulf region was 1.181 billion yuan. In the modified CE model, both the improvement of the questionnaire and the improvement of the utility equation contribute to the improvement of the validity of the evaluation results; their contribution degree is equal. Regarding the choice model, based on the correction, the public's willingness to pay per capita values for strengthening the protection of mangroves are (in order): the improvement of biodiversity, mangrove forest coverage, water quality, and the appreciation of the landscape. Related values are 53.89 yuan, 47.00 yuan, 35.46 yuan, and 17.29 yuan, respectively. The results provide a scientific basis for the formulation of ecological management policies of coastal wetlands by the government.