广州南沙地区湿地生态系统的服务功能与保护

南沙地区是广州城市空间“南拓”发展战略的重点开发区域。南沙地区湿地资源丰富，其开发建设必须正确处理湿地开发与保护的关系，实现社会经济与生态环境可持续发展。在南沙地区湿地资源现状调查的基础上，分析了南沙地区湿地生态系统的服务功能，依据功能的重要程度与湿地资源的稀缺性，指出了南沙开发中应加强生态敏感区、红树林生境、水生动物繁殖区与鱼类洄游通道、自然林植被区、历史文化遗迹与自然景观分布区等重要湿地的保护，并提出了相应保护措施。

Service and Conservation Functions of Wetland Ecosystem in Nansha District,Guangzhou City

Nansha District is the major development zone in carrying out the program of enlarging urban areas in the southern regions Guangzhou City. There are substantial wetland resources in Nansha District which provide large land and favorable environment for the development. According to the classification principle of Chinese and foreign wetlands and the features of Pearl River estuary, and the result of survey by using satellite remote sensing image taken in November 2002, the wetlands in Nansha District were classified into 5 types and 12 subtypes with total area of 53322.13hm 2 , accounting for 89.2% of the whole precinct. Among these wetlands, the delta alluvium plain and the water area of estuary are the two largest subtypes, occupying 47.9% and 45.7% of the total area of wetlands, respectively. Meanwhile, there are 318 species of higher plants and 312 species of wild animals in wetlands. Wetlands are unique and important resources of great ecological benefit. The ecological service functions of wetland ecosystem in Nansha District are as follows: 1) storing water, preventing flood and protecting coast; 2) improving territorial environment; 3) reducing pollution; 4) conserving biodiversity; 5) providing for sightseeing and tour. Therefore, the relationship between utilization and conservation of wetlands in Nansha development should be properly settled to further the sustainable development of economy and environment. On the basis of investigation of the wetland resources and analysis of the service functions of wetland ecosystem in Nansha District, it was pointed out that wetlands whose ecological functions were very important or which were rare in this region should be conserved in Nansha development, such as ecologically sensitive areas, mangrove swamp, marine animals' propagating places, fish's passage between freshwater and sea, wildwood areas, and wetlands where there are historic or natural relics. In the end, some countermeasures for the wetland conservation were put forward.