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Since the publication of the third assessment report of The Intergovernmental Panel on Climate Change, vulnerability to climate change has become an important research question. Vulnerability assessment on the urban scale has become a major issue. This paper describes a conceptual framework for modelling vulnerability at the urban scale, the Climate Change Vulnerability Assessment model. The model is applied to Shanghai, a typical geographically vulnerable and rapidly-urbanizing case study area. Using Arc-GIS, a vulnerability map was created for understanding the spatial dynamics of climate change vulnerability in Shanghai. An additional process, combined with the weighting coefficients, produced different vulnerable areas. Based on the vulnerability map, we located several high risk areas. The vulnerability of each area was assessed. Identifying the risks in each case and associating them with a specific region can be useful for decision makers. [ABSTRACT FROM AUTHOR]

It is well received in the space syntax community that traffic flow is significantly correlated to a morphological property of streets, which are represented by axial lines, forming a so called axial map. The correlation co-efficient (R 2) approaches 0.8 and even a higher value according to the space syntax literature. In this paper, we study the same issue using the Hong Kong street network and the Hong Kong Annual Average Daily Traffic datasets, and find surprisingly that street-based topological representations (or street-street topologies) tend to be better representations than the axial map. In other words, vehicle flow is correlated to a morphological property of streets better than that of axial lines. Based on the finding, we suggest the street-based topological representations as an alternative GIS representation, and the topological analyses as a new analytical means for geographic knowledge discovery. [ABSTRACT FROM AUTHOR]

This paper investigates the spatial distribution of inbound and domestic tourist flows to cities in China and their growth rates using exploratory spatial data analysis. This method is a set of GIS spatial statistical techniques that are useful in describing and visualizing the spatial distribution, detecting patterns of hot-spots, and suggesting spatial regimes. The global Moran's I statistics for inbound and domestic tourist flows reveal strong positive and significant spatial autocorrelation. Furthermore, the Moran significance maps indicate four significant inbound tourism hot-spot areas in 1999 and 2006 (the Beijing-Tianjin cluster, the Yangtze River Delta cluster, the Fujian coast cluster and the Pearl River Delta cluster), and five significant domestic tourism hot-spot areas in 2002 and 2006 (with the addition of the Chengdu cluster). Based on the results, we show that tourism flows are polarized into clusters and remain very stable over time. As has been seen in other countries, hot-spots tend to be in insular and coastal areas, and associated with cities that are higher in China's urban hierarchy. Implications are drawn, such as priority of resource allocations for hot-spot area and the utilization of spillover effects from hot-spots. [ABSTRACT FROM PUBLISHER]

Climate change and human activities have changed a number of characteristics of river flow in the northwest of China. Numerous problems such as water resource shortage, drying up of rivers, water pollution are the direct consequences of these changes. In this paper, we used the example of Yulin city in northwest China to assess the spatio-temporal characteristics and driving forces of annual river flow changes. Our research was based on the long-term time series of hydrological data from 1956 to 2005, to analyse annual flow in four main rivers (Kuye River, Tuwei River, Wuding River and Jialu River). The river flow depends upon the runoff characteristics of the river catchment, therefore we used variation ratio, variation index, unevenness, Runoff-Concentration Degree (RCD) and Runoff-Concentration Period (RCP) to determine the change in runoff characteristics of the four main rivers flows of the Yulin city. We tested the tendency of runoff by the Mann-Kendall non-parameter statistical method to obtain the temporal evolution law. At the same time, Kriging spatial interpolation and GIS were used to derive the spatial evolution law. The dates of climate change (precipitation) and human activities were also used to calculate the driving forces for annual runoff changes of the rivers’ catchments. Through the accumulation curves and multi-recursive techniques, we built the correlation between precipitation and runoff. The driving factors for annual runoff change were then calculated by using the runoff coefficient method. Results showed that the distribution of annual runoff was uneven and had a small accumulation in July and August, especially in Kuye River, and there seemed to be a significant reducing trend in annual runoff. Isolines and the thematic map of Mann-Kendall tests U(R) revealed that the Tuwei River's catchment is the most affected catchment, with annual runoff substantially changed. At the 5% significance level, precipitation did not significantly drop compared with annual runoff. We also found that precipitation is not the only factor responsible for the decreased annual runoff. Therefore we included human activities affect in this case study by using the past 25 years land use, water conservancy and urbanisation data. We discriminated the impacts of climate change and human activities on the surface runoff by multi-recursive analysis method and runoff coefficient method. The results showed that human activities are the direct cause for the changes of river runoff. The results of the study also revealed that the Wuding and Jialu rivers had the most and the least changes in the runoff respectively; this phenomenon should be seriously considered for future water resources planning and management. [ABSTRACT FROM PUBLISHER]

Erosion control is one of the most important functions of forest ecosystems, and its accurate assessment is useful to illuminate the importance of forest ecosystem services for humans so as to rationally conserve forest resources. This paper examines Zhangjiajie National Forest Park, the first national forest park in China, to seek practical methods for assessment of the forest erosion control function using a geographical information system (GIS). The results show that the potential and actual amounts of soil erosion are 2.92 million ton and 0.14 million ton per year, respectively, in Zhangjiajie National Forest Park. The total reduction in soil loss reaches 2.77 million ton per year with the existence of a forest ecosystem. The erosion control function of near mature, mature and over mature broadleaf forest is excellent, and natural forest conservation and natural restoration of the degraded forest ecosystem can provide the largest benefits in soil erosion control. Nearly all the near mature, mature and over-mature forest in the park is at the top and in steep mountain areas, and could be rationally cut and utilized by local communities, but extensive timber felling should be strictly prohibited. [ABSTRACT FROM AUTHOR]

Rapid land development in rapidly growing countries has created a series of land-use problems. The implementation of sustainable land use can alleviate some of these problems. It needs a set of tools for the exploration, design, modification, illustration, and evaluation of alternative planning scenarios. This paper demonstrates that the integration of cellular automata and agent-based modelling can provide a spatial exploratory tool for generating alternative development patterns. Sustainable development strategies are embedded in the modelling to regulate agents' behaviours. The use of agents can help to represent human-environment interactions in solving complex land-use problems. It is able to examine the effects of different stakeholders in influencing the process of land development. The proposed model has been applied to the simulation of planning scenarios for residential development in a rapidly expanding city in the Pearl River Delta. [ABSTRACT FROM AUTHOR]

The aim of this research was to evaluate the predictive performances of frequency ratio (FR), logistic regression (LR) and weight of evidence (WoE), in flood susceptibility mapping in China. In addition, the ensemble WoE and LR and ensemble FR and LR techniques were applied and used in the evaluation. The flood inventory map, consisting of 196 flood locations, was extracted from a number of sources. The flood inventory data were randomly divided into a testing data-set, allocating 70% for training, and the remaining 30% for validation. The 15 flood conditioning factors included in the spatial database were altitude, slope, aspect, geology, distance from river, distance from road, distance from fault, soil type, land use/cover, rainfall, Normalized Difference Vegetation Index, Stream Power Index, Topographic Wetness Index, Sediment Transport Index and curvature. For validation, success and prediction rate curves were developed using area under the curve (AUC) method. The results indicated that the highest prediction rate of 90.36% was achieved using the ensemble technique of WoE and LR. The standalone WoE produced the highest prediction rate among the individual methods. It can be concluded that WoE offers a more advanced method of mapping prone areas, compared with the FR and LR methods. [ABSTRACT FROM AUTHOR]

Based on remote sensing and Geographic Information System techniques, multi-temporal Landsat data were used to monitor land use/cover changes (LUCC) in the Nanchang area during 1989–2010. Quantitative and spatiotemporal indicators derived from the transition matrix for overall changes, intensity analysis for inter-category transitions, and spatiotemporal analysis of intra-category variations were constructed to analyze the spatiotemporal LUCC evolution. The study results show that urban and industrial land rapidly and continually expanded. The spatial extent of rural settlements shrunk while their distribution density increased. Cultivated land showed a tendency of spatially continuous loss and fragmented distribution, whereas the spatial pattern of forest tended to concentrate. The extents of ponds and reservoirs remained stable, but spatial changes were obvious. Rivers and bottomlands decreased significantly and tended toward fragmentation. The overall LUCC pattern showed that construction land rapidly sprawled while cultivated land decreased substantially, indicating an accelerating stage of urbanization and industrialization. Although rigid land requirements for urbanization had to be satisfied, land development and consolidation across forests and water body areas, as well as adjustment of agricultural structure, laid the foundation for a transition toward intensive land use in the Nanchang area. [ABSTRACT FROM PUBLISHER]

Digital Agriculture is one of the important applications of Digital Earth. As the global climate changes and food security becomes an increasingly important issue, agriculture drought comes to the focus of attention. China is a typical monsoon climate country as well as an agricultural country with the world's largest population. The East Asian monsoon has had a tremendous impact upon agricultural production. Therefore, a maize drought disaster risk assessment, in line with the requirements of sustainable development of agriculture, is important for ensuring drought disaster reduction and food security. Meteorology, soil, land use, and agro-meteorological observation information of the research area were collected, and based on the concept framework of ‘hazard-inducing factors assessment (hazard)-vulnerability assessment of hazard-affected body (vulnerability curve)-risk assessment (risk),’ importing crop model EPIC (Erosion-Productivity Impact Calculator), using crop model simulation and digital mapping techniques, quantitative assessment of spatio-temporal distribution of maize drought in China was done. The results showed that: in terms of 2, 5, 10, and 20 year return periods, the overall maize drought risk decreased gradually from northwest to southeast in the maize planting areas. With the 20 year return period, high risk value regions (drought loss rate ≥0.5) concentrate in the irrigated maize region of Northwest china, ecotone between agriculture and animal husbandry in Northern China, Hetao Irrigation Area, and north-central area of North China Plain, accounting for 6.41% of the total maize area. These results can provide a scientific basis for the government's decision-making in risk management and drought disaster prevention in China. [ABSTRACT FROM AUTHOR]

The ecological and environmental relationship between a natural reserve (NR) and its surrounding area is a ‘hotspot’ in the human–environment relationship. However, the effect of landscape pattern of the surrounding land-use changes on the NR has not been thoroughly explored. How to protect the NR has become an issue of major concern. This research analysed the land-use/land-cover (LULC) change of the NR and its surrounding area using Landsat Thematic Mapper (TM) images and applied theories of landscape ecology to study the effect of the surrounding LULC on the wetland landscape of the NR in Tianjin, China. The results show that (1) the wetland area decreased from 122,461.11 ha in 1988 to 111,753.99 ha in 2008 while the built-up area expanded from 11,983.22 ha in 1988 to 20,197.71 ha in 2008; (2) landscape diversity will increase along with direct LULC in the NR and its surrounding area, where human activities have already diversified the original wetland landscape; and (3) the unitary landscape has been replaced by diverse landscapes and the land type that was once dominant has lost its status. Restoring the watershed wetland is a good method for realising protection of the NR. [ABSTRACT FROM PUBLISHER]

Lodging is one of the major problems in maize production which causes severe yield loss every year all over the world. In the present study, the lodging suitability of different maize varieties in target growing environments was investigated based on geographical information science. A total of 401 maize planting counties in northeast China and northern China were selected as study areas. The mean and standard deviation of environment accumulated temperature in vegetative stage of maize were calculated from raw temperature data obtained from 167 meteorology stations in these areas. The variety lodging resistance was determined based on the data of national regional variety trials for maize, and the environment lodging stress was measured using field survey data on lodging. Probability analysis based on the calculated values of environment accumulated temperature in vegetative stage of maize was utilized to determine whether a maize variety can be physically mature in a planting county, and lodging suitability of the variety was evaluated with geographical information science combining variety lodging resistance and local environment lodging stress together. A new maize variety NH1101 was taken as an example to illustrate the modeling and calculating procedures. The result shows that, from southwest to northeast of the study areas, the overall suitability trend changes from nonsuitable to suitable, then to not very suitable. And it is demonstrated that the lodging suitability is not only related to the variety resistance but also to the local environment stress. [ABSTRACT FROM AUTHOR]

This study investigates the spatial dependence and mechanisms of international and domestic tourist distributions in 299 cities in mainland China through a set of Geographical Information Systems (GIS)-based spatial statistical tools. The results show that during the period of investigation (1999-2007), there was a significant degree of neighbouring effect (i.e. positive spatial correlation) in both international and domestic tourist distributions. We have also highlighted that tourism development in a given city is dependent on the developments in neighbouring cities. Specifically, the tourist distribution shows a polarized (core - periphery) spatial pattern, which is strongly connected to the economic development level and tourism resources of the cities. Furthermore, the findings reveal tourist distribution clusters that underscore the importance of geographical focus. Overall, the results imply that policy makers are encouraged to pay attention to patterns of tourist distribution. [ABSTRACT FROM AUTHOR]

In this study, a web-GIS based support system for rural residential land consolidation in China was designed to evaluate the potential and objectives for rural land consolidation. It was developed using ASP.NET. ArclMS, ArcSDE and SQL Server technologies. The results show: (I) that according to the potential evaluation, the major rural consolidation areas are concentrated in the north-east of China, east China, north China and Inner Mongolia. These account for 65% of the total potential area in 2010; (2) that based on the rural consolidation objectives analysis, the major rural consolidation areas are concentrated in north-east China, east China, north China, Inner Mongolia and Xinjiang province. These account for 75% of the total consolidation objective area in 2020; (3) that the data can be shared and transported by the system on the internet. [ABSTRACT FROM AUTHOR]

To make a dynamic analysis of ecological capacity and a quantitative analysis of ecological compensation, to promote the sustainable development in a nature reserve, and to make Po-yang Lake Nature Reserve as an example, the authors obtained information on land-use change in the years 1985, 1995, 2005 in Po-yang Lake Nature Reserve based on RS and GIS. Ecological capacity was quantified and its development change, spatial characteristics, and the sustainable development status of the nature reserve with ecological deficits and surpluses were analysed. Results show that land use had been stable since the Po-yang Lake Nature Reserve came into existence. The change compared grassland (increased 15.22%), water body (increased 7.05%) and unused land (decreased 18.19%). The ecological capacity improved from 1985 to 2005 (the per capita ecological capacity from 0.8284 ha to 1.0534 ha). Among nine villages and towns in the reserve, the ecological surplus villages and towns were Wucheng, Tiehe and Changyi, the ecological balance villages and towns deficit were Sanjiao and Shahu. The remainder were in ecological deficit. In all of the nature reserve, the ecological capacity in the southeastern area was in surplus but that in the north-west was in deficit. The degree of ecological harmony was 1.414, which proves that the sustainable development state in Po-yang Lake Nature Reserve was under sustainable status. In 2005, the ecological footprint efficiency was 8382 yuan/ha, and the agricultural ecological footprint efficiency was 3204 yuan/ha. The lowest ecological compensation was 1725 yuan per family or 403 yuan per person, and the equal ecological compensation was 3798 yuan per family or 888 yuan per person. [ABSTRACT FROM AUTHOR]

With the development of hydrographic work and information techniques, the traditional work mode is not suitable for the Chinese Marine Safety Administration Bureau (CMSAB). Aiming at the separation of charts production and management, a new idea that is the integration of production, management, and quality control is presented. Geographic Information System (GIS), Management Information System (MIS), Office Automation (OA) and Spatial Database Management (SDM) advanced techniques are introduced into the workflows in CMSAB. To realize information sharing, a mixed mode with Browser/Server (B/S) mode and Client/Serve (C/S) mode are adopted. Based on the above ideas and strategies, an integrated system named Hydrographic Production And Management Information System (HYPAMIS) was developed. The whole workflow and three subworkflows including survey management workflow, production workflow, and quality control workflow of are outlined after re-engineering the CMSAB organization. Some design principles and key techniques of the HYPAMIS including the cooperation of GIS and MIS, object-oriented spatial data model and management, data management based on database, and security control are illustrated in detail. Then the implementation of the system is introduced briefly. Finally, performance evaluation of the system and future work is given. [ABSTRACT FROM AUTHOR]