The Cumulative Ecological Impact Assessment Of The Wintering Waterbird Habitat In The Yancheng Wetland National Wildlife National Nature Reserve Project

In recent years, with the rapid development of economy, some construction projects have been extended to nature reserves. Due to the lack of nature reserve management and the systems of regulations, construction projects become more disorder. All of these aggravate the degradation of ecosystem and decrease the suitable habitat of various creatures, especially the waterfowl.On the basis of previous studies, this paper chose waterfowl in the Yancheng wetland national nature reserve as the research object and land area of experimentation area in nature reserve as the research scope. The study area was divided into four parts from north to south which are north experimental area N1, N2 and south experimental area S1,S2. According to the habit of wintering waterfowl in nature reserve and the characteristics of the construction projects, crane representative species (red-crowned cranes), ducks and geese were selected as the representation and indication of wintering waterfowl and land use, biomass loss and human disturbance were chosed as main factors to construct comprehensive evaluation index model of wintering waterfowl habitat. It can quantify the effects of the construction projects on the wintering waterfowl and analyse the change of suitable habitat of the wintering waterfowl. The corresponding habitat restoration compensation measures which based on the analysis. were put forward There are the main results and conclusions of this paper.First of all, the cumulative ecological impact index of the wintering waterfowl in the nature reserve under the influence of construction projects was 1.22, reaching at the moderate level, which shows that project although not yet reach the level of excessive development,the ecological impact of waterfowl has been relatively significant. Reserve area of four pieces in experimental area of N1 affected by the construction project is the most, the largest cumulative comprehensive ecological impact index was 2.02, and reaching the level of intensity. Which are followed by the N2 experimental area and accumulated comprehensive ecological impact index is 1.70, reaching to the moderate level. Both of S2 and S1 are mild level and accumulated comprehensive ecological impact index were 0.42 and 0.20. Wind power projects have the most impact on ecological influence in all kinds of construction projects.Secondly, according to the preference of wintering waterfowl to different habitat types, dividing the area into three levels are followings: suitable, moderately suitable and unsuitable. We analyze the change of suitable habitat for overwintering water birds before and after the construction project under the support of space technology.The results show that the most changes in waterfowl unsuitable habitat is 2400%, the changes of suitable habitat and general suitable habitat are relatively small, reducing to 18% and 13% respectively. The waterfowl habitats loss proportion is the largest in N1, and S1 is the smallest. In addition, from the perspective of the absolute area of waterfowl habitats loss, S2 is the largest and S1 is the smallest.Finally, in allusion to the the environmental impact of the construction projects and the suitable habitat of the winter waterfowl, five measures were proposed to slow down the effect of construction projects from three perspectives of habitat compensation, biomass compensation and human disturbance compensation, which are compensation in different places, returning fishery back to wetland engineering,food supplement, reconstruction and optimization of construction site and strengthen supervision and management.