The Coupling Relationship Between Urbanization And Regional Ecological Risk In Poyang Lake Ecological Economic Zone

With the rapid developm ent of urbaniza tion, human excessively intervened on ecosystems, the urban land wantonly expansio n, overcrowding, high strength industrial activities, traffic jam and other serious problems appeared, wh ich deteriorated the city’s ecological environment, led to the rising of regional ecol ogi cal risk. How to achieve the coordinated development between new ur banization and ecolog ical environment, maintaining ecosystems health, is a major issue in currently we facing in developm ent. In this context studying the coupling rela tionship between urbanization and regional ecological risk, is a basic for recognizing, avoiding, preventing and m anaging of the regional ecological risk in the process of urbanization. And it is possible to provide a scientific suggestion for the new urbanization.It made the Poyang Lake Ecological Economic Zone as exam ple,establishing urbanization measurement index, from a single index and comprehensive index, respectively.Then with these two m ethods measured the urban level of Poyang Lake Ecological Economic Zone from 1990 to 2013;The regional ecol ogical risk was conducted based on land use change. W hile the land use change date was from four Landsat TM images(included 1990,2000,2010and2013), that were interpreted as basic information sources.The gray correlation analysis, variab le correlation analysis, c enter of gravity coupling, cold-hot spots coupling were as model to quantitative analyze the coupling relationship between urbanization and regional ecological risk, and discussed the coupling relationship change in space and time sequence in Poyang Lake Ecological Economic Zone from 1990 to 2013. Then according to coupling relationship urbanization between regional ecological risks divided dif ferent types of coupling area; Finally, it put forward the development of urbanization and aversion regional ecological risk strategies for different coupling regional. The main conclusions were as follows:(1)The level of urbanization continued to increase and show a significant difference in spatial in the Poyang L ake Ecological Economic Zone from 1990 to 2013. According to single index, such as the proportion of urban population and the proportion of urban land,it found that the proportion of urban population and the proportion of urban land from 21.64%,1.49% increased to 46.48%,4.75%, respectively.It was into the m iddle stages of urbanization. The single index of urbanization showed that the center of gravity m oved to west in space. The single index of urbanizat ion also showed that the urbanization’s low value gathered significantly in general,but becam e weak. As the proportion of urban population,it suggested that hot spots gradually increased and moved to the east, and cold spots declined, but advanced to southern. As the proportion of urban land, it found that the hot spots gathered to the central of area, the cold spots reduced to the east.According to comprehensive index of urbanization,the level of urbanization increased to 0.6118 from the 0.2707.It was belonge d to the high urbani zation stage. Also its subsystems such as population, econom ic, spatial and social ur banization increased from 0.2785,0.1593,0.2270,0.3435 to 0.4908,0.7710,0.5522,0.5718,while the economic urbanization raised significantly. The center of gravity m igrated to southwest with the distance of 2.45km in space, the low value gathered remarkably in general, while the hot spots decreased, gathered in southeast,the cold spots was down,and gathered in the northeast.(2)The regional ecological risk grew quic kly, which was from 0.0113 to 0.2865. It become to a medium ecological risk stage. The center of gravity migrated to the southeast with 0.51km. The high value gath ered significantly, but declined, and focused on central and northern, the cold spots incr eased stably, strengthened the gathering in the northeast and west in Poyang Lake Ecological Economic Zone from 1990 to 2013.(3)The coupling relationship between Urbani zation and regio nal ecological risk in spatial and temporal evolution was remarkable in Poyang Lake Ecological Economic Zone from 1990 to 2013. From the aspect of ti me sequence, firstly, based on gray correlation analysis,the relationship of urbanization and regional risk was closely,their gray correlation index improved gradually.The proportion of urban population and the proportion of urban land use,comprehensive urbanization all coul d prove it. T heir gray correlation indexes added respectively from 0.6056,0.4911,0.7621 in 1990, to 0.7224,0.5031,0.8101 in 2013. It also found that the link between comprehensive urbanization and regi onal ecological risk was most closely. Secondly,the result of Pear son correlation analysis presented that, the proportion of urban population variable, the proportion of ur ban land variable and the variables of com prehensive urbanization a 11 kept a high and strong correlation with regional ecological risk variable in general.T heir variable correlation coefficients was-0.382,0.822,0.781, respectively. And in phases th ey also exhibited a very high correlation.It meant with the developm ent of urbanization,the regional ecological risk arose.(4)From the spatial seq uence,the center of gravity migration direction revealed that the proportion of urban population, the pr oportion of urban land, com prehensive urbanization and regional ecological risk a 11 moved to southward in the overall. Next, according to the cold-hot spots coupling analysis, urbanization and regional ecological risk coupled in cold-hot spots rem arkably. The proportion of urban population and regional ecological risk hot spots coupling was weak and decreas ed year by year, the cold spots coupling was unstable; the proportion of urban land and regional ecological risk had strong cold spots coupling relationship. C omprehensive urbanization an d regional ecological risk’s hot spots had a coupling relationship,but the coupling area constantly fluctuated. The cold spots had a stable relatio nship, and increas ed year by year. It suggested that urbanization and regional ecological risk grew similar on the spatial evolution.(5)The coupling type between urbanization and regional ecolo gical risk ch anged constantly. It declined from six categories to four types in the P oyang Lake Ecological Economic Zone from 1990 to 2013. Until 2013, the rem ained types were moderate urbanization&low ecological risk (in Gu ixi, Fuliang, Dongxiang, W uning), moderate urbanization&moderate ecological risk (i n Pengze, Poyang, Douchang, Y ugan, Yujiang, Leping, Jiujiang, Yongxiu, Jinxian, Nanchang,Xinjian, Anyi, Gaoan, Fengcheng, Xingan), high urbanization&low ecological risk (in Jingdezhen, Ruichang, Dean, W annian),high urbanization&moderate ecological risk (in Nanchang, Jiujiang, Xingzi, Hukou, Y ingtan, Fuzhou, Xinyu, Zhangshu).Depending on the t ypes of different coupling, it proposed different development strategies.