Landscape Ecological Security Pattern Optimization Approach Base On Grain Size Reverse Method

Landscape ecological security pattern regard the interrelation between landscape space pattern and ecological process as its main research contents, whose optimization approach is an effective way to construct a better ecological environment and to improve person and natural harmonious evolution in landscape ecology. This study taked the Xiuying district in Haikou City for example to analyses the landscape ecological security pattern of Xiuying district by landscape ecological security pattern optimization approach, in addition, it put forward corresponding prioritization scheme and suggest, in order to provides basis and reference for ecosystem construction. In the optimization process, in order to make the result become more reasonable and having practical guiding significance, the article put forward a new method to confirm the origi and scale of ecological source, which is based on the theory and method of landscape pattern, spatial analysis and inverse method, called grain size reverse method. Additionally, thinking of the interrelationship between ecological resistance, kriging is used to improve the establishment of ecological resistance surface. The results are presented as follows:(1) When the grain size is400m, the ecological landscape component is the best ecological landscape component, it hinders the working of ecological flow least. There are18ecological sources in Xiuying district now, the scale of ecological sources is very different, and the maximum one should be protected and constructed specially in the optimization process. The minimum area of ecological source is38.5hm2. Hence,38.5hm2is the Construction reference standard of the new ecological sources in Xiuying district. It enhances the connectivity of ecosystem by integrates more ecological plague to form ecological source, to improves the quality of ecological environment.(2) The critical distance of ecological in Xiuying district service is800m, when the grain size beyond800m, the connection between ecological plaque components become very faintly. In the optimization process, we should pay attention to the maximum distance of different ecological sources, to make sure as much as scope under the serive of ecological sources. The density of ecological function points is low when the distence threshold is around200m under the grain size of10m. So, we should pay attention to the ecological construction of ecological plaques that the spacing distance is about200m specially.(3) The spatial distribution characteristics of ecological sources in Xiuying district can be summarized as follows:whole is disperse and locality is centralized, the ecological sources can be divided into two group, south ecological source group and north ecological source group. The eastnorth of Xiuying district is not has ecological source, so when we carry out the optimization process, to improve the quality of this district should be prior. There are6plough lands and5construction lands need to change the use type, and the total scale is hm2, they form some large ecological sources by link the ecological landscape components which are interfacing, and they have a very important function to the improvement of ecological environment.(4) At present, there are17ecological corridors in Xiuying district, includ14plough ecological corridors and3urban ecological corridors. The longest one and the3urban ecological corridors produces a great reinforcement for the harmonious development of human and environment, they are the focal point of ecological construction. There are11ecological function nodes on the ecological corridors in Xiuying district, includ8plough ecological nodes and3urban ecological nodes. The ecological node which is on the longest ecological corridor should take the ecologcial source as standard to construct it.3urban ecological nodes should take the secondary ecologcial source as a standard to construct them.(5) It is feasible to use the grain size reverse method to choice the best ecological sources component, the result supply a objective reference to the choice of ecological sources. The best ecological landscape component which is chosen by the method has the strongest connection and hinders the process of ecology least. The optimize measure has a strong theory base and reality conduct meaning. The grain size reverse method can reflect the connectivity of landscape component.(6) The comprehensive ecological resistance surface was formed by dominant ecological resistance surface and recessive ecological resistance surface, it is able to combine landscape type with the interact of ecological resistance, and it may simulates the reality of ecological resistance of Xiuying district preferably. The contrast of dominant ecological resistance surface and recessive ecological resistance surface can reflect the potential weakness of ecology system.