Research On Land Use Ecological Security Pattern In Jiangxi Province

With the “Poyang lake ecological economic area planning”,“Jiangxi central Soviet area planning”,“Gan river new district”,“the northwestern Jiangxi planning”,“the west Jiangxi economic transformation planning” gradual implementation,Poyang lake ecological area,Jiangxi central Soviet area and other areas will experience a rapid economic development in the future,the spatial pattern of development will be adjusted in Jiangxi province.Analysis the speed and intensity of the process of land use change,the conversion of land use,the driving mechanism,and its ecological environmental effects,is a major issue of Jiangxi.It is effective to explore the ecological security situation from land use change and land cover change.With the help of land use date,the security situation of the land ecosystem can be evaluate dynamically,and then an ecological security pattern can be establish based the landscape ecology methodology,the ecological security pattern can provide active references for ecosystem protection and sustainable use of land resources in Jiangxi.Based on the remotely sensed date of Jiangxi Province,we used man computer interactive image processing methods to acquire the land use date in 2005,2010,2013.With the help of GIS and Ucinet software,the spatial-temporal variations of land use change were quantitatively analyzed,including land use change rate,land use transformation pattern and land use intensity.The results showed as follows:(1)The integrated dynamic degree of land use showed a decreasing tendency.During 2005-2013,the area of grassland,arable land and unutilized land decreased gradually,the area of construction land increased gradually,the water area increased during 2005-2010 and then decreased during 2010-2013,forest area decreased during 2005-2010 and then increased during 2010-2013.(2)Since 2005,the land use interchange flows between arable land,forest land and construction land have been dominant in the land use change of Jiangxi province.In general,the density of the area of land use change was decreased and the range of high density was reduced.The hot area of land use transformation was distributed in patches or dots.(3)In general,the land use intensity in Jiangxi province showed increasing tendency during 2005-2013,and the gap narrowed between the area of high land use intensity and the area of low land use intensity.Affected by the central policy,the Poyang Lake ring area and Gannan area become the area of high land use intensity obviously.The ecological impact of different land use types and intensity can show on regional ecosystem structure changes directly,and the changes of structure and function of land ecosystem would profoundly affect regional ecosystem health.Therefore,ecological risk assessment in terms of landscape structure is an effective method to study regional ecological risk pattern.Based on an ecological risk assessment model established through land use structure,the study try to explore ecological security pattern in large scale area and provide a reference for the optimization of land utilization in Jiangxi.This study present Jiangxi Province as a case study to explore the impact of land use change on ecological risk.The spatial-temporal variation of the ecological risk were investigated by spatial autocorrelation and geo-statistics.It shows that about 9.2% of the total areas experienced land use changes,presenting a remarkable trend of non-agricultural transformation.With the reduction of farmland and the rapidly expansion of construction land,the average ecological risk index(ERI)increased from 0.237 in 2005 to 0.246 in 2013.The spatial distribution of ERI showed a positive autocorrelation and significant local spatial clustering.The spatial disparity of ERI was obvious,i.e.the north is higher than the south.Based on the result of spatial interpolation of ERI,the study area were further divided into five categories.The high risk and relatively high risk region expanded rapidly,mainly located in Poyang Lake area,Nanchang,Jiujiang and central Jiangxi,with the area proportion increasing from 9.08% in 2005 to 11.68% in 2013.The spatial distribution of ERI grade was significantly related to topography.The distribution of ERI showed an obvious topographic directivity with the ERI grade increasing.In order to study the effects of land use pattern change on habitat quality in the background of urbanization,the InVEST model was applied to calculate the contributions of habitat threats(urban area,rural construction area,main roads)to habitat degradation,and to assess habitat quality changes between 2005 and 2013,the results of habitat quality assessment shows that the ecological risk is negative relate to habitat quality,the two results get from different assessment model show a mutual verification relationship.According to the patch area and the importance of ecosystem services,and in combination with habitat quality of patch,we designated the core ecological patch as sources of ecological security pattern,and utilized the minimum cumulative resistance model to build comprehensive ecological security patterns,thus a number of ecological security pattern portions and positions were identified,including ecological corridors,ecological points and three-level ecological function zones.