厦门湿地生态系统服务功能价值评估

Evaluation on Service Value of Wetland Ecosystem in Xiamen City

厦门湿地具有多种重要的生态系统服务功能,对其服务功能进行评估是湿地保护与合理开发的基础,也是确保湿地资源的可持续性利用的基础。依据2003年Landsat TM遥感影像解译数据,将厦门市湿地生态系统类型划分为浅海水域、滩涂、河口水域、河流、水库、红树林、滩涂、沙滩、盐田等9个类型,着重针对湿地提供的栖息地、湿地产品、涵养水源、污染净化、抵御海洋灾害、旅游以及文化科研等7种服务功能,采用生态经济学的理论和方法来评估各项生态系统服务功能价值。结果表明:厦门湿地的服务功能总价值为135.54亿元/a,其中湿地的污染净化功能的价值量最大,为66.46亿元/a,其次旅游休闲的功能价值为33.14亿元/a。

Wetlands, locate at transitional zone of water area and land, provide many environmental functions maintaining ecological balance and regional stability. Wetlands are the most productive ecosystems in the world, and provide many important services to human society.Furthermore wetland is also the ecologically sensitive and adaptive systems. Costanza. R, an ecologist of the United States, attempted to put a price on global ecosystem. He estimated the current economic value of 17 ecological services for 16 biomes, giving the annual value of global ecosystem services, which accounted to US $ 33 ×10^12, of which, ocean ecosystem, consisting mostly of bay, estuary, seaweed, coral reef, tidal fiat and mangrove, supplies US $ 20.9 × 10^12, which is 63 percent of the total value. These data presented obviously importance of ecological function of coastal wetland. Xiamen city, with various wetland and abundant bio - diversity, lies in the southeast coast of china. According to the regulation of investigation on wetland resource and the definition of wetland in Ramsar Convention on Wetlands （http ：//www. ramsar, org） , 9 categories of ecological system were divided, which included shallow sea, estuary, river, silt beach, sand beach, breed, mangrove, Brine pan, pond and reservoir. The natural wetlands, whose area is more than 256 km^2, include shallow sea, estuary, mangrove, sand beach, tidal fiat and river. Among those wetlands, dominating coastal wetlands which consist of shallow sea, tidal fiat, sand beach and mangrove, and natural wetland are respectively account for 90% and 65% of areas of all wetland. In this contribution, the services of wetland ecosystem are evaluated in order to estimate the importance of wetland ecosystem to regional development of Xiamen city. These studies are beneficial to providing scientific basis for making policies on wetlands conservation and management, and ensuring the sustainable development of wetland resources. The area data of different wetland types are extracted from Landsat Thematic Mapper （TM） image measured in March 2003. Some statistical data are derived from the Statistical Yearbook ofXiamen （Xiamen Municipal Statistical Bureau, 2003）. This paper pay more attention to the 7 services functions of wetland ecosystem, which include those services of water purification, water conservancy, culture and scientific research, wild species habitat, erosion control and organic matter production. The economic theory and methods are used to evaluate the value of wetland eco system＇s services, and GIS technologies are also applied to data processing, statistical analysis and compiling the spatial distribution map of services value of wetland ecosystem. The results indicate that the total value of wetland ecosystem is about 135.54 × 10^8 Yuan （ Chinese RMB） in 2003, which equal to 17.8 percent of the gross domestic product（GDP） in Xiamen city（760 ×10^8 Yuan）. According to values of these seven kinds of services, the value decrease from water purification to tourism, wetland production, Erosion control, culture and scientific research, wild species habitat and water conservancy. Among all these services values, value of purification, tourism, wetland production and erosion control are contributed to 95.7%. Water purification value is 66.46× 10^8 Yuan, and the value of tourism, wetland production, Erosion con-trol, culture and scientific research, wild species habitat and water conservancy are respectively34. 14 × 10^8 Yuan, 16.82 ×10^8 Yuan, 15.83 × 10^8 Yuan, 2.59 × 10^8 Yuan, 1.96 ×10^8 Yuan, 1.22 × 10^8 Yuan. Variation between different ecosystem service＇ contribution is obvious among these nine wetland ecosystems. Specifically, the shallow sea and tidal flat ecosystem play the most important role in the ecosystem services. Shallow sea contributed 47.59% of the total value; the second is tidal flat with 37.97% of all values. The service value of mangrove, estuary, river, sand beach, breed, brine pan, pond and reservoir are 0.07×10^8Yuan, 1.18×10^8 Yuan, 2.46×10^8 Yuan, 0. 13 ×10^8 Yuan, 14.31 ×10^8 Yuan, 1.19×10^8 Yuan, respectively, The service of natural wetland is far higher than artificial wetland . The spatial distribution of wetland ecosystem services of unit area showed Mangrove is more than Silt beach, Shallow sea and Estuary,, River, Sand beach, Breed, Pond, Reservoir and Brine pan. Wetland, especially natural wetland ecosystem plays an important role in sustainable development and protection of land resource in Xiamen city. In the process of urbanization and exploitation, natural wetlands around city are continuously transformed into farming, industry, port and residential area ere, which lead to loss and degradation of wetlands. Consequently wetland ecosystem services are greatly discounted. The assessment of wetland ecosystem service provides us a new concept of conservation, and development of wetlands. Primary evaluation of the wetland ecosystem services is favored to cognizing the value of wetland resources. Rationally developing natural wetland and protecting wetland ecological environment are beneficial to not only the sustainable utilization of wetland ecological service, but also the sustainable development of regional economy and society in Xiamen city. In this paper, estimating service of wetlands ecosystem is preliminary study; and more detailed methods of assessment should be applied to study of wetlands＇ ecosystem service in the future.