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The key to studying urban sustainable development depends on quantifying stores, efficiencies of urban metabolisms and capturing urban metabolisms' mechanisms. This paper builds up the metabolic emergy account and quantifies some important concepts of emergy stores. Emphasis is placed on the urban metabolic model based on the slack based model (SBM) method to measure urban metabolic efficiencies. Urban metabolic mechanisms are discussed by using the regression method. By integrating these models, this paper analyzes the urban metabolic development in Beijing from 2001 to 2010. We conclude that the metabolic emergy stores of Beijing increased significantly from 2001 to 2010, with the emergy imported accounting for most of the increase. The metabolic efficiencies in Beijing have improved since the 2008 Olympic Games. The population, economic growth, industrial structures, and environmental governance positively affect the overall urban metabolism, while the land expansion, urbanization and environmentally technical levels hinder the improving of urban metabolic efficiencies. The SBM metabolic method and the regression model based on the emergy analysis provide insights into the urban metabolic efficiencies and the mechanism. They can promote to integrate such concepts into their sustainability analyses and policy decisions. [ABSTRACT FROM AUTHOR]

Farmland protection and delimitation in the urban fringe considers not only natural factors but also the spatial characters and site factors. Taking Daxing District, Beijing in China as a case study, this paper used landscape ecology and power-law methods to analyze and evaluate farmland loss during the period of 2004-2007 based on the interpretation results of SPOT5 remote sensing images in 2004 and 2007. At the patch level, we selected four landscape indices, namely patch size, shape index, the nearest neighbor distance between farmland and construction land (including residential land and other construction land), and cropping type, to evaluate the risk of farmland loss and establish a farmland site analysis indicator system. The results showed that patch size and shape index have a significant positive correlation with farmland loss, whereas the distance to construction land has a clear negative correlation with farmland loss. As regards cropping type, fallow farmland is much easier for non-agricultural use than cultivated farmland. The relative transition ratio among vegetable land, fallow farmland and cultivated farmland is 1:5.6:1. The patch size of lost farmland follows a power-law distribution, indicating that not only small parcels but also large parcels can be lost. Patch size less than 4 ha or more than 15 ha is in high loss risk, between 4 ha and 10 ha in medium loss risk, and larger than 10 ha and less than 15 ha in low risk. Farmland with a more regular shape has a higher likelihood of loss. Patch shape index less than 2.0 is in high loss risk, between 2.0 and 3.0 in medium loss risk, and larger than 3.0 in low risk. Construction land has a varying impact on farmland loss, the residential land effected distance is 1000 m, and that of the other construction land is 2000 m. This analysis showed the relationships between site factors and farmland loss, and the analysis framework can provide support and reference for farmland protection and delimitation of prime farmland in China. [ABSTRACT FROM AUTHOR]

Using datasets on high-tech industries in Beijing as empirical studies, this paper attempts to interpret spatial shift of high-tech manufacturing firms and to examine the main determinants that have had the greatest effect on this spatial evolution. We aimed at merging these two aspects by using firm level databases in 1996 and 2010. To explain spatial change of the high-tech firms in Beijing, the Kernel density estimation method was used for hotspot analysis and detection by comparing their locations in 1996 and 2010, through which spatial features and their temporal changes could be approximately plotted. Furthermore, to provide quantitative results, Ripley's K-function was used as an instrument to reveal spatial shift and the dispersion distance of high-tech manufacturing firms in Beijing. By employing a negative binominal regression model, we evaluated the main determinants that have significantly affected the spatial evolution of high-tech manufacturing firms and compared differential influence of these locational factors on overall high-tech firms and each sub-sectors. The empirical analysis shows that high-tech industries in Beijing, in general, have evident agglomeration characteristics, and that the hotspot has shifted from the central city to suburban areas. In combination with the Ripley index, this study concludes that high-tech firms are now more scattered in metropolitan areas of Beijing as compared with 1996. The results of regression model indicate that the firms' locational decisions are significantly influenced by the spatial planning and regulation policies of the municipal government. In addition, market processes involving transportation accessibility and agglomeration economy have been found to be important in explaining the dynamics of locational variation of high-tech manufacturing firms in Beijing. Research into how markets and the government interact to determine the location of high-tech manufacturing production will be helpful for policymakers to enact effective policies toward a more efficient urban spatial structure. [ABSTRACT FROM AUTHOR]

Mechanism and modeling of the land subsidence are complex because of the complicate geological background in Beijing, China. This paper analyzed the spatial relationship between land subsidence and three factors, including the change of groundwater level, the thickness of compressible sediments and the building area by using remote sensing and GIS tools in the upper-middle part of alluvial-proluvial plain fan of the Chaobai River in Beijing. Based on the spatial analysis of the land subsidence and three factors, there exist significant non-linear relationship between the vertical displacement and three factors. The Back Propagation Neural Network (BPN) model combined with Genetic Algorithm (GA) was used to simulate regional distribution of the land subsidence. Results showed that at field scale, the groundwater level and land subsidence showed a significant linear relationship. However, at regional scale, the spatial distribution of groundwater depletion funnel did not overlap with the land subsidence funnel. As to the factor of compressible strata, the places with the biggest compressible strata thickness did not have the largest vertical displacement. The distributions of building area and land subsidence have no obvious spatial relationships. The BPN-GA model simulation results illustrated that the accuracy of the trained model during fifty years is acceptable with an error of 51% of verification data less than 20 mm and the average of the absolute error about 32 mm. The BPN model could be utilized to simulate the general distribution of land subsidence in the study area. Overall, this work contributes to better understand the complex relationship between the land subsidence and three influencing factors. And the distribution of the land subsidence can be simulated by the trained BPN-GA model with the limited available dada and acceptable accuracy. [ABSTRACT FROM AUTHOR]

As responses to metropolitan suburbanization and rural urbanization, the formation and evolution of urban fringes should be understood against the background of overall economic development and spatial reconstruction of entire metropolises. At the same time, however, endogenous interactions between industrial structure and spatial patterns of non-agricultural activities are also worthy of scholarly attention. Since the 1980s, studies on urban fringes in China have been restricted by the lack of micro-level data. This paper investigates the spatial expansion and structural evolution of the urban fringe by taking the case of Beijing and uses systematic firm-level data in 1996 and 2001 from the National Census of Basic Units. The diversity of distribution patterns across industrial sectors brings about two interrelated results. On the one hand, structural adjustment of non-agricultural industries promotes the expansion and spatial evolution of the urban fringe. On the other hand, the stability and dynamics of industrial structure coexist in the moving urban fringe. This study also reveals that the outward-moving urban fringe is the optimal location for manufacturing, especially heavy manufacturing, as well as traditional producer and consumer services. However, industries with spatial stickiness such as tourism and sports have not moved with the fringe. Most advanced services remain concentrated in the city center. The authors argue that it is essential for understanding and managing urban fringes to take into account spatial evolution and industrial structural adjustment together with their interaction with each other. [ABSTRACT FROM AUTHOR]

Based on multi-source data, this paper evaluated the economic value of ecological services in the Yeyahu Wetland Nature Reserve, Beijing, China. The ecological services of wetland included gas regulation, water quality improvement, biodiversity maintenance, erosion control, water supply, recreational opportunity, raw material supply and existence value. Multiple conventional evaluation methods were used to calculate the value of eight wetland services. The results showed that significant values came from biodiversity maintenance and recreational opportunity. The main reasons were as follows. Firstly, Yeyahu Wetland Nature Reserve was the habitat for migrant birds, and government had payed more efforts to protect precious birds. Secondly, the population is large in Beijing. People enjoyed going outside and enjoyed the natural and artificial wetland scenes. At the same time, most people were prepared to pay for wetland conservation. The decline of vegetation cover made the economic value of erosion control the lowest. While the shrink of water resource and the deteriorative water quality caused the economic value of water supply lower. The evaluation results could help decision-makers understand the present status of the Yeyahu Wetland Nature Reserve and provide a scientific basis for strategic decision. [ABSTRACT FROM AUTHOR]

Based on the data of gross domestic product (GDP), industrial added value and the proportion of industrial employees from 2000 to 2008, this paper studies the effect of industrial structure change on the regional economic growth of Beijing-Tianjin-Hebei Metropolitan Region in China using the shift-share method. The results show that: 1) In the 21st century, the industrial output of three industries, namely, primary, secondary, and tertiary, and the GDP grew rapidly in the study period. The tertiary industry grew the fastest; it had the largest contribution to the GDP and meanwhile had become the most competitive industry in the metropolitan region. 2) The development of cities within the region was not balanced. Firstly, compared with Tianjin, Beijing, as one of the two core cities, was more rational in the industrial structure. Secondly, the surrounding eight cities, which are Shijiazhuang, Qinhuangdao, Tangshan, Langfang, Baoding, Cangzhou, Zhangjiakou, and Chengde, were all uncompetitive than the two core cities. 3) There was a great industrial gradient in the region (especially between the two core cities and the cities of Tangshan, Baoding, Zhangjiakou, Chengde, Cangzhou, and Langfang). As a result, it is foreseeable that the industry transfer in the Beijing-Tianjin-Hebei Metropolitan Region will be one of the trends in regional development, and the industry transfer is inevitably to promote the regional integration. [ABSTRACT FROM AUTHOR]