Abstract:Wetlands are the kidneys of the Earth. Wetland ecosystems are vital in regulating the Earth's environmental balance. Caohai is one of the three Plateau Freshwater Lakes in China, located in the Yunnan-Guizhou Plateau within the Yangtze River watershed area, having an important role in the downstream water balance. The Caohai Wetland ecosystem provides people not only with essential ecosystem goods, such as raw materials and freshwater resources, but also has the potential to provide many services that are critical for regional sustainable development. However, the lack of information on the ecological economic value of Caohai Wetland hinders cooperation among different stakeholders. Furthermore, inappropriate development and pollution are threatening the functioning and the resultant benefits provided by these wetland systems. The economic valuation of Caohai Wetland ecosystems can help to clarify the tradeoffs among ecosystem services and social goods and services towards wise wetland management. In this paper, we divided the wetland ecosystem services into 3 main categories, provisioning services, regulating services, and cultural services, based on the underlying ecological mechanisms and beneficiary analyses. The 3 categories were further subdivided into 10 subcategories, food production, raw material production, water provisioning service, flood mitigation service, groundwater recharge service, water purification service, climate regulation service, gas regulation service, recreational service, and biodiversity and landscape conservation service. We evaluated the economic value of these 10 subcategories of wetland ecosystem services based on the year 2010 using different methodologies, such as the market value method, shadow engineering method, travel expense method, and contingent valuation method. According to the results of this valuation, the total economic value of the 10 subcategories of ecosystem services provided by Caohai Wetland was 4.39×108 Yuan RMB, of which provisioning services, regulating services, and cultural services contributed 0.74×108 Yuan RMB, 1.14×108 Yuan RMB, and 2.51×108 Yuan RMB, respectively. The major contributing services among all these wetland ecosystem services were recreational service, biodiversity and landscape conservation service, water provisioning service, and flood mitigation service. The total value of these four services was 3.78×108 Yuan RMB, which accounted for 86.05% of the total value, with recreational service value accounting for 29.93%, the biodiversity and landscape conservation service value accounting for 27.20%, the water provisioning service value accounting for 15.53%, and the flood mitigation service value accounting for 13.39%. The recreational value topped the others in the economic valuation, followed in order by biodiversity and landscape conservation value, water provisioning value, flood mitigation value, climate regulation value, groundwater recharge value, gas regulation value, raw material production value, water purification value, and food production value. The area of Caohai Wetland covers only 0.43% of Weining County, but the economic value of this wetland was 16.40×104 Yuan RMB per hectare, which is 16.91 times higher than the annual gross domestic product (GDP) per hectare of the county. Hence, it is inappropriate to transform Caohai Wetland into farmlands. The results of this study reflect the importance of Caohai Wetland in supporting the regional economy. Therefore, it is now important to raise public and government awareness to protect the wetlands for their continuous flow of sustainable services. Decision makers can incorporate the economic value of wetland ecosystem services to create ecological compensation mechanisms while dealing with the contradictions among different stakeholders.