The Landscape Pattern Optimization On The Basis Of Biodiversity Conservation In Guangxi Beibu Gulf Economic Zone

The beibu gulf economic zone is a new hot spot of open development in southeast China, and also is the core area of the economic communication between China and Southeast Asia. Since the beibu gulf economic zone development plan was approved by the national government in 2008, the large-scale investment and construction has been accelerated. Large numbers of forests and cultivated lands have been transformed into construction land, thus destroyed the species habitat and threatened biodiversity, and also caused the mass change of regional landscape structure and its spatial pattern. Therefore, understanding the current status of biodiversity in the region and how to protect biodiversity is a problem to be solved.The land use type change made the species habitat destroy and shrink, the excessive use by human can even make the species die out, many species such as Cyathea podophylla、Erythrophleum fordii、Madhuca pasquieri are endangered, which are listed in the IUCN red list of species, these bring a serious threat to the regional biological diversity.In view of the background, this paper selected the beibu gulf economic zone as the study area, based on the TM remote-sensing images in 1990,2001,2009 as the main data source, by using “3S” technology and the landscape ecology theory, it selected the landscape index to analyze the landscape pattern change during the 20 years. And then it selected the species endangered degree、landscape diversity index、habitat types and the nature reserve type as four criterion layers to build a biodiversity abundance evaluation system, using analytic hierarchy process(AHP)to evaluate the biodiversity status. Finally, based on the landscape ecological flow accumulative cost distance model, it established ecological source、ecological corridor and ecological node and built the network which was good for biodiversity protection and maintenance, and also promoted the smooth operation of the landscape ecological flow. It provided reference for the regional biodiversity protection from the scale of the landscape. The main conclusion:1.Forests and cultivated land are the main two types of patches in the area, the total area of them account for nearly 95% of the total area, which occupy absolute advantage; About the changes, from 1990-2009, the most obvious change of the land use was the expansion of construction land and the decrease of grassland, construction land area increased nearly six times, grass land and unused area fell nearly 60% and 62.3%; The degree of landscape fragmentation increased all the time, the landscape fragmentation index of three periods were 0.033, 0.038 and 0.048, so do the different type patches, especially the cultivated land and forest land disturbance intensity were strong, the fragmentation increased quickly and the growth was obvious after 2001. The landscape fragmentation bring a great challenge to the regional ecological environment and biodiversity protection.2.The biodiversity abundant area are mainly distribute in Shangsi、 Longzhou、Pinxiang、Mashan、Shanglin、Pubei and so on. The town、construction land and the coast are the least abundant area. The extremely rich region covers an area of 1287.7km2, accounts for 1.8% of the total area; the relatively rich region covers an area of 2347.3km2, accounts for 3.2% of the total area; the rich region covers an area of 8665.4km2, accounts for 12% of the total area; the generally rich region covers an area of 29624km2, accounts for 40.8% of the total area; the not rich region covers an area of 30712.4km2, accounts for 42.2% of the total area.3.It established 18 forest patches and 6 water patches as ecological source, built 47 Ecological corridor and 35 nodes, to build the point on the surface of the line way to maintain the biodiversity protection network. The optimization measures are to protect the existing core batches, to avoid the interference effect from the land development. The corridor construction should be strengthened the east to west direction in the future. The network can provide a scientific reference for regional development planning, notice and make sure the avoiding collision area for biodiversity protection in the process of land development, to protect the regional biodiversity more effectively.