| Commonly called as Mindong ,Ningde is located in the northeast of Fujian province and closely related to three-big economic zones of the Yangtze River delta, Pearl River delta and Taiwan as it is on the south of Wenzhou (a developed city in Zhejiang province), Fuzhou (capital city of Fujian province) to the north and to the west of Taiwan. Recently, the large-scale construction of infrastructural facilities including Wen-Fu high-speed rail Shen-Hai expressway have greatly promoted the economic development of Ningde region and have produced far-reaching impacts on regional eco-environment and ecological security at the same time.Ningde region is composed of 9 counties or municipalities, namely, Jiaocheng, Fu'an, Fuding, Xiapu, Gutian,Shouning, Pingnan, Zherong, Zhouning. In this study, field survey data and TM images (1990,2001 and 2007) were combined to explore in detail the landscape spatial-temporal dynamics for the 9 counties or municipalities and fractal characteristics, landscape stability and driving force mechanism for landscape dynamics of Mindong region by means of 3S technologies. On the basis of the work above, the Mindong eco-security indicator system was then established to assess the eco-security condition, dynamics and spatial variability of Mindong region at landscape scale. At the same time, many means such as gray correlation, RBF-ANN, AIS-PPE and SVM were introduced to regional eco-security assessment in Mindong region. The main results are as following.1.The analysis of spatial pattern and temporal dynamics of land use/cover in Mindong region show that forest and cultivated land were the dominant landscape types in Mindong region(85% in terms of land area). Landscape change from 1990 to 2007 was mainly related to forest with forest area reducing 27326 hm2. Cultivated land, built-up land and water body increased by 38386, 12019 and 3538 hm2, respectively and the unused land were developed at large-scale. Landscape change for this period was characteristic of the increase in landscape diversity, evenness and fragmentation, especially in landscape fragmentation which increased from 0.597 to 2.131 from 1990 to 2007. The distribution of land resources showed high regional heterogeneity with the extent, scale and variability of land resources exploration being higher in coastal areas than those in inland areas.2.Fractal analyses of landscape types in Mindong region show that built-up land was the most disturbed landscape type. The urban sprawling from 2001 to 2007 led to high regional variability. The spatial structure fractal dimensions for each landscape type in Mindong region were relatively high in all the studied year. Spatial structures of forest and cultivated land were complex which can be attributed to the interweaving with other landscape types and topographic influences. Cultivated land, non-use land and forest land were evenly spatial distributed with the evenness index declines over time whereas building area and water body showed high and increased aggregation over time. The stability of landscape types followed the order of built-up > forest> non-use land>cultivated land> water body. in addition it is found that the stability of various landscape types showed fluctuation and a rising trend as a whole. 3.The analysis of driving force mechanism for land use change in Mindong region shows that climate change was mainly responsible for the non-use land change whereas the changes in other land use types were mainly related to population increase, social development, technology invest and other factors. The formation and evolution of landscape pattern of Mindong region was the product of physical and artificial factors with the role of human activity being determinant.4.Mindong landscape eco-security assessment and its spatial-temporal dynamics analysis show that the eco-security index was higher than 0.8 and showed a rising trend, whether at the whole region scale or county scale, suggesting Mindong region had good and improving eco-environmental quality on the whole. The eco-security index showed positive spatial autocorrelation at range of 45 kilometers which declined over time. The eco-security index showed aggregated distribution pattern with the regions of high eco-security index and those of low eco-security index were clustered, but both the regions of high eco-security level and those of low eco-security index declined in terms of area. Structural factors played an determinant role in Mindong landscape eco-security whereas the role of non-structural factors were moderate but on the rise. The big topographic difference in Mindong region help to increase spatial auto-correlation and reduce the range of spatial analysis.5.Mindong regional eco-security assessments show that Mindong region is at the level of high eco-security. The level of science and technology and pressure from resources and environment impeded and limited the harmonious development of Mindong regional eco-security. The comparison of the behavior of gray correlation , RBF-ANN, AIS-PPE and SVM in the eco-security assessment in Mindong region shows that gray correlation , RBF-ANN and SVM behaved well whereas AIS-PPE behaved relatively bad, which provide important information for tool selection for regional eco-security assessment.6.Eco-environmental change and driving forces analysis show that most counties of Minding region were at the level of excellence in 2001 and 2007 except Zhouning in 2001 and Fuding in 2007, which is attributable to the facts that Mindong region is rich in biodiversity and ecologically stable and therefore suitable for human living. Eco-environmental change results verify the conclusions above mentioned.In the end, the environmental problems with eco-construction in Mindong region were addressed and the corresponding advice and suggestion are given in this paper.In sum, land resources dynamics analysis and eco-security assessment of Mindong region is expected to provide important information for management and planning and spatial allocation of land resources of Mindong region and the economical construction in Economic Zone on the Western Coast of the Taiwan Straits.
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