Abstract:
Abstract: The rapid urbanization in China has caused a series of ecological and environmental problems. The irrational utilization of land resource poses the risk of regional ecological security, especially in ecological fragile regions. Consequently, the study on the optimization of ecological security pattern is essential to the regional ecoplanning and optimal allocation of land resources, and beneficial to the sustainable development. In order to explore the ways of optimizing regional ecological security pattern and ensuring regional ecological safety and rational utilization of land resources, this study was conducted in Huailai County located between 115°16′-115°58′E and 40°04′-40°35′N. By interpreting the remote sensing images of 1993, 2003 and 2013, the study analyzed the hot regions of land use change in Huailai county through the information map spectrum of land use change and by establishing Competitive Advantage of Construction Land and Ecological Land (CACE) Model. The study also analyzed the competitive advantage distribution area and divided the competition critical line of construction land and ecological land. In view of landscape ecology, the study constructed the single factor ecological security pattern of hydrology, geological hazard prevention, biodiversity conservation and soil and water conservation respectively. The maximum value of each single factor was utilized to construct the regional comprehensive ecological security pattern. The optimization direction of ecological security pattern was proposed according to the distribution of dominant region of construction land and ecological land. The results showed that: 1) the hot regions of land use change in Huailai County mainly appeared around Guanting Reservoir and Shacheng Town as the continuous decrease of reservoir water area and the expansion of construction land; 2) the dominant regions of construction land were mainly distributed in the central plains, while the dominant regions of ecological land were mainly distributed in the mountainous regions and the basin regions in the middle part. The distribution exhibited a significant topographic gradient feature; 3) the acreage of the regional comprehensive ecological security pattern in Huailai County was 1470.59 km2, accounting for 82.51% of the total area. The acreage of basic ecological security pattern was 521.33 km2, accounting for 29.25% of the total area, while the acreage of satisfactory ecological security pattern and ideal ecological security pattern was 206.93 km2 (11.61%) and 742.34 km2 (41.65%) respectively. The basic ecological security pattern was mainly distributed in the periphery of critical line and endured relatively low pressure from construction land expansion. The satisfactory ecological security pattern was mainly located in the ecological dominant area and partly limited the construction land expansion, serving as a critical ecological buffer zone of Huailai County. The ideal ecological security pattern was mainly in the interior of critical line and receives more pressure from construction land expansion. Then the government should emphasize the construction of ecological corridor network, which guides the disperse integration of nature patch into construction land in the form of corridor and small plaque. The research methods and results can provide valuable information for regional ecological planning and land use structure optimization.