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Urban socio-economic development and spatial urban expansion has led to the loss and fragmentation of habitat.Global climate change adds to the gravity of these effects.An ecological network describes a network of habitats and connecting corridors that is mapped using habitat suitability and land use/land cover data.Connectivity within a habitat network ensures a flow of material,energy and information among the various patches,and allows species′ movement from inappropriate to appropriate areas.This ensures the abundance of species reaches a dynamic equilibrium at the network level and also means that the disappearance of species from any particular patch does not change the function of the regional ecosystem network.Thus,management of ecological network is an effective measure to counter the loss of biodiversity caused by reductions in habitat quality and area,as well as habitat fragmentation,in the context of rapid urbanization and climate change.The least cost path method is a way to construct and analyze ecological networks based on landscape spatial structure and dynamic biological processes.Based on the understanding that the characteristic of the matrix is one of the important factors determining the movement of species between patches,the least cost path method gives different cost values to different landscape types,and generates a cost surface to substitute the Euclidean space.Therefore,the dispersal paths generated by the least cost method are similar to those of actual species movement.Qingdao city is located in the eastern coastal region of China where the economy is relatively well-developed.The region is also where marine and terrestrial ecosystems meet.In this paper,we propose a wetland ecological network in the Qingdao district based on remote sensing and geographic information systems technology.We evaluate the overall structure of the network and the importance of individual patches using the correlation length index and betweenness centrality index,and use the findings to identify optimal strategies and make recommendations.In this paper,we discuss the following five questions:(1) How to classify landscapes?(2) How to determine the cost value of each landscape type?(3) How to evaluate the importance of each core patch?(4) How to evaluate the importance of stepping stones?(5) What is optimal management strategy for the wetland systems in the study area? The result shows that the network connectivities are very different in terms of threshold levels of path cost.Core patches in Jiao Zhou bay wetlands and Da Gu river have a relatively high degree of importance.Stepping stone patches with a high degree of importance are found in two zones: one comprising Jiao Zhou bay,Jiao Lai river and Wei He river estuary,and the other comprising Jiao Zhou bay and Ding Zi bay.In this paper,we propose a wetland management plan based on an ecological network including one core area,two axes and a ring in Qingdao and its surrounding area,to provide a scientific and quantitative basis for the selection of urban development sites within Qingdao City that simultaneously achieves wetland ecosystem protection.These network construction and evaluation methods can be used for other ecological network analysis.

Urban socio-economic development and urban spatial expansion has led to the loss and fragmentation of habitat.Global climate change adds to the gravity of these effects.The survival of wildlife species is subjected to enormous pressure due to natural environmental changes and human activities.Agent-based models(ABMs) are computer simulation models analyzing and simulating human or animal behavior through the integration of learning,adaptation,evolution and logical analysis.ABMs study the overall system characteristics by analyzing internal elements of the system(such as the interaction among individual agents,and agents with the environment) with a bottom-up approach.The agents in ABMs can complete given objectives,perceive and respond to changes of the external environment through the default logic control,and respond to stimuli from other agents and the external environment through learning and adaptation functions.This paper designed an agent-based evaluation model of an ecological pattern,which was used to analyze the impact of different woodland patterns on species survival and dispersal.The model focused on the logic control of survival and dispersal of agents,and used the dispersal strategy integrating CRW and LW models,which combines the advantages of these two models.The survival of the agent is control by the age-specified U-shaped survival curve and determination function considering their own energy and environmental risks.The model was developed on the GIS platform,realizing the seamless integration of the agent model and GIS,which could then be applied to real geographical environment simulation.Qingdao is a city located in the eastern coastal region of China where the economy is relatively well-developed.The region is also where marine and terrestrial ecosystems meet.Woodland is mainly distributed in the Laoshan Mountains in the east,the Daze Mountains in the north,and the Dazhu,Xiaozhu and Tiejue Mountains in the south.In the study area,the ecological environment is deteriorating,and various wildlife species are being impacted,with some species being endangered or facing extinction.This paper selected the woodlands in the Qingdao district as the study object,analyzing the effect of different spatial patterns on the survival and spread of woodland species.Simulation results showed that,compared with the original state,species populations and migration have improved significantly under different levels of ecological network framework,and the higher the level of ecological network framework,the more obvious the improvement.The distance between patches had a large influence on the dispersal of simulated species because they were not able to arrive at patches that were far away from the original patch.Therefore,this paper makes the suggestion that an approach integrating wetland and woodland systems could strengthen woodland system functional contact in the study area.It is suggested that the region around Jiaozhou Bay and the mainstream of Dagu River be used to increase the spatial distribution of woodland.Based on the simulation results,suggestions for the woodland ecological pattern construction are given below:(1) ensure that the large woodland can not be destroyed;(2) the wetland system district in the middle of Qingdao is an ideal place for a new woodland construction;(3) the ecological network framework can be used as a spatial reference for an ecological barrier to prevent the spread of urban land into woodland.

On the basis of the data of water utilization in seventeen cities of Hubei Province from 2003 to 2008 and the comparative advantage principle, the scale advantage indices and benefit advantage indices were calculated with the normalized revealed comparative advantage index(NRCA)model, and the weighted comparative advantage value was obtained. The seventeen cities were clustered by the comparative advantage indices(CAI) , then the space-time difference was analyzed. And we find that the driving factors which can bring on the fluctuation of CAI of productive water, were natural conditions, natural resources, population, economic development and water utilization efficiency ; and the driving factors of the fluctuation of residential water was urbanization level. The results showed that the superiority regions of irrigation water utilization were in Jianghan Plain, and the superiority regions of forestry, livestock and fisheries water utilization were in areas along Yangtze River and herbage regions in Hubei, and the superiority regions of industrial water utilization were in the traditional industrial districts, such as Wuhan, Huangshi and Shiyan. The results can present decision foundation for the optimal distribution of water resources.