Characteristics And Changing Trend Of Coastal Wetland Ecosystem In Macau

The coastal wetland ecosystem in Macau is an important midway station for the international migratory waterbirds in their flyways, and it is also an important habitat for the world threatened bird species, black-faced spoonbill Platalea minor in the winters. It is reported that about 2.73% of black-faced spoonbill Platalea minor in the world live through the winter in this area. So far, however, little research work has been done on the coastal wetland in Macau due to various reasons. Therefore, investigations on the characteristics of coastal wetland ecosystem in Macau can not only be beneficial to the sustainable development of the ecological environment of the coastal wetlands in Macau, but also can increase Macau's position and reputation in terms of the environmental protection by fulfilling the international obligations protecting the world endangered black-faced spoonbill Platalea minor effectively. This is the first systematic survey focusing on the coastal wetland ecosystem in Macau carried out by the Macau's local environmental NGO. In the current survey, ecological environment of the coastal wetlands in the artificial island of Nanwan Lake, Taipa-colanva mudflats and Longhuanpuyu Egrety, three main and typical coastal wetlands in Macau was assessed by comparing historical data and conducting field investigation. This survey concentrated on: 1. geography characteristics of natural geography and water resources in Macau; 2. characteristics of water environment of coastal wetlands in Macau; 3. characteristics of phytoplankton of coastal wetlands in Macau; 4. characteristics of zooplankton of coastal wetlands in Macau; 5. associations among phytoplankton and environmental factors in the wetlands of Macau; 6. characteristics of plant community of coastal wetlands in Macau; 7. characteristics of bird community of coastal wetlands in Macau. The results obtained from our survey show that: 1. the coastal wetlands in Macau are degrading; 2. rivers in Macau are in a eutrophic state; 3. diversity indexes and evenness indexes reflect that the water in coastal wetlands in Macau has been severely polluted; 4. correlations among phytoplankton and environmental factors indicate that temperature has relatively little impact on the phytoplankton, while the concentration of nutrients has the greatest effects on the phytoplankton; 5. wetland plants have been seriously threatened by the invasive Ipomoea cairica and Mikania micrantha, resulting in fewer plant species and a simple-structured community in coastal wetlands; 6. the decreasing biological capacity of wetlands bring about the decline of the number of waterbird. Our findings suggest that the wetlands in Macau show a degenerative trend due to some unsolved problems such as the inefficiency of wetland benefit and utilization, as well as deficiency of protective measures. The innovations of the current study can be concluded as follows: 1. it is the first systematical survey on the characteristics and changing trend of the wetland in Macau, where has been believed to be the most important place for the world threatened bird species, black-faced spoonbill Platalea minor living through the winters; 2. some effective suggestions and strategies also have been proposed to protect the wetland ecosystem in Macau based on these characteristics.