Study Of Ecological Security In Yancheng National Nature Reserve

With the deterioration of the global environment, the development of environmental protection and the theory and practice of sustainable growth, the issue of ecological security has now become the focus of concern for governments of all countries, scholars and even ordinary people as well. Despite its great importance in ensuring the security of global ecology, littoral wetland, as the gradient belt between marine and terrestrial ecosystems, is confronted with threats to its own ecological security due to the fact that littoral zones are generally densely populated, economically developed and frequently disturbed by human activities. The conflict between social and economical development and ecological conservation in the littoral zones is now intensifying, which thus causes some further problems to the security of combined ecosystem of nature, society and economy.Yancheng National Nature Reserve, while providing a site for birds from different biological zones to meet, serves as an important stopover for the East Asian and Australian migrant waterfowls and their wintering ground. Among the six migrating routeways throughout the world, three of them are in China and the migrating routeway alongside the eastern coastal area constitutes the most important one both home and abroad. It is estimated that around 50% of migrant birds migrate from the south to the north or vice versa through this migrating routeway alongside the eastern coastal area. Yancheng National Nature Reserve, as the most important sector on this routeway, plays host to about 300,000,000 migrant birds in spring and autumn every year.In recent years, owing to the need to develop economy in towns and counties around the Reserve, more and more tideland has been reclaimed and many industrial parks have been constructed gradually. To make things even worse, the drains of some chemical factories are adjacent to the Reserve. For the present, these surrounding industrial parks, Chenjiagang Industrial Park, Binhai Industrial Park, Sheyang Industrial Park, Dafenggang and Hangyang Economic Development Zone, the industrial zones like Qionggang Town and Habitation area like Gangkou and other small-sized industrial areas are quite close to the Reserve, bringing about industrial and domestic waste and severely threatening the ecological security of the Reserve.In order to cope with the serious threats to the ecological security of Yancheng National Nature Reserve, the researcher studies the ecological security of the Reserve and that of the red-crowned cranes (Grus japonensis) in this dissertation. Specifically, the study is as follows. Firstly, based on the characteristic of multi-spacetime of the coastal wetland's evolution in Yancheng, the researcher analyzes the developmental history, evolutionary trend and changes in the structure of land utilization of its littoral tideland and wetland. He summarizes the existing research fruits, interprets data of remote sensing in different periods and examines reports on some on-the-spot investigations, on the basis of which, he explores the ecological function and structure of the littoral tideland and wetland. Secondly, the researcher utilizes the PSR model to construct an ecological security index system by referring to relevant research fruits home and abroad, consulting experts, conducting comparative analysis and considering the structure and function of the tideland and wetland in Yancheng National Nature Reserve for rare waterfowls in wetland. Thirdly, by using ecological security index system and analytic hierarchy process (AHP), he further gives an analysis on the state of ecological security of the Yancheng National Nature Reserve for rare waterfowls in wetland. Fourthly, he studies the biological adaptivity of red-crowned cranes (Grids japonensis) and the effect of human activity on their ecological security and evaluates their ecological security state with the help of GIS and RS technologies. Fifthly, he investigates the ecological security state of Yancheng National Nature Reserve for wetland rare waterfowls and puts forward corresponding ecological compensation strategies for the Reserve according to the Theory of Ecological Compensation. Meanwhile, after examining the ecological security pattern of red-crowned cranes (Grus japonensis), he comes up with suggestions for environmental management and protection in the Reserve so as to tackle problems with the present management.Results of the present study are in the following.i. the present status of Yancheng National Nature Reserve for wetland rare waterfowlsThe ecological security status is not quite good in the whole Reserve, with the ecological security levels for each region and the whole reserve approaching the prewarning limit. The comprehensive ecological security level for the Reserve is as low as 0.493, ranking below the prewarning limit. The best sector in the Reserve, Sheyang Sector, enjoys the highest ecological security level, 0.606, yet only slightly higher than the upper prewarning limit, while the lowest level of 0.407 in Xiangshui Sector is quite close to the dangerous level.ii. Ecological security pattern of red-crowned cranes (Grus japonensis) in the ReserveFor the present, the Reserve still constitutes a quite suitable habitat for red-crowned cranes (Grus japonensis). Good condition area covers around 64.78% of area of 1,476.55km~2, ideal condition area occupies around 15.96% of area of 363.85km~2, and mal-condition and bad condition area include about 4.72% of area of 107.56km . The way of land utilization is the primary factor influencing biological security of red-crowned cranes (Grus japonensis) and water quality is another important factor. According to comparative analysis of typical regions, hardly half of the Reserve has undergone great changes in terms of ecological security for red-crowned cranes (Grus japonensis) from 1992 to 2005, but nearly 40% of the area has ddeteriorated. Besides, 12.85% of area has improved, while only 2.84% of area has improved to a great extent in this respect.Part of Sheyang and Dafeng sectors have improved a great deal in terms of ecological security for red-crowned cranes (Grus japonensis), mainly because of the construction of Yancheng National Nature Reserve for rare waterfowls in wetland and Dafeng Nature Reserve for Milu deer, which have a great impact on the protection and improvement of local eco-environment. With the increasing development of the coastal towns and counties around the Reserve, however, the ecological security status for red-crowned cranes (Grus japonensis) worsens in more and more regions, with the lowest percentage of over 30% in Sheyang sector and the highest of over 35% in both Dafeng and Dongtai sectors. The main cause of such a phenomenon is that natural eco-environment appropriate for red-crowned cranes (Grus japonensis) suffers from damage and has been changed into artificial eco-environments inappropriate for red-crowned cranes (Grus japonensis) like housing and urban areas.iii. strategies for sustainable development in the ReserveLocated in the comparatively less developed and densely populated area in Jiangsu Province, Yancheng National Nature Reserve for rare wetland waterfowls faces great pressure of social and economical development. With the development of marine economy recently, stricter requirements have been made to the utilization of coastal wetland, and enormous menace is thus posed to the sustainable development in the Reserve. Study on the ecological security of the Reserve in the relevant towns and counties further provides proof to this point. The ecological security levels in Xiangshui and Binhai are both below 0.5, which is on the brink of dangerous level. In light of the problems existing in the management and protection in the Reserve and the analysis of the ecological security pattern of red-crowned cranes (Grus japonensis), the researcher finds that growing human activities have affected the ecological security of red-crowned cranes (Grus japonensis) and sees urgency for necessary measures.iv. construction of ecological compensation mechanism in Yancheng National Nature ResreveThe agents for ecological compensation in nature reserves comprise the central and local governments, beneficiary parties in the process of developing and exploring the reserves and destroyers of them, while the patients of compensation include the destructed wetland resources and eco-environment, those who help to protect the eco-environment or participate in some construction projects for conservation and those who sacrifice in terms of giving up some equal rights for development for the sake of eco-environmental protection. Altogether four methods can be adopted to set ecological compensation standards in the reserves, i.e., determining compensation standards based on the service value of the ecosystem, the cost of protection, protection of the loss and willingness to pay and to be repaid. Sources of compensation fund come from government, marketing operations, etc.The new ideas and contributions brought by the thesis are as follows:(1)The thesis evaluates and researches into the ecological security of the nature reserve, by considering the ecological security of both the region and the main species protected, with the double concern of the security of nature and humanbeings. It's a new way to study the ecological security of the nature reserve.(2)Lacking detailed statistical data in the nature preservation zone, the thesis analyses the appropriateness of habitat of the red-crowned crane, selects a few key elements as evaluating indicator from the aspects of the appropriateness of habitat and artificial interference, and evaluates the state of the spatial distribution and dynamic change of ecological security of red-crowned crane. It is a new try for the stydy of ecological security of the nature reserve.