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Wen Lin 《Urban geography》2013,34(7):901-922
While local governments have been one of the major user groups of GIS, there is still little research on how GIS development in local government might be intertwined with urban governance, particularly in non-Western contexts. Drawing upon insights from GIS implementation, critical GIS, and governmentality studies, this article seeks to bridge this gap by examining the implications of Chinese urban government GIS practices amidst China's changing urban governance. Through an in-depth case study of Shenzhen, this article analyzes how urban GIS has been transformed from a practice involving internal organizational workflow automation, into a more active dimension of the governance of urban spaces—reflected in the expanding practice of “geo-coding” the urban landscape. “Geo-coding” here refers to a broadly defined spatial practice of carving and reconstructing a rational urban space. GIS practices have constituted a particular form of geographic rationality that seeks to govern at a distance while simultaneously regulating the urban environment, intersecting with the broader transformations of China's urban governance. These GIS developments have been largely government-centric rather than citizen-centric, yet they provide possibilities for new forms of spatial knowledge production for citizen participation in urban governance. 相似文献
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Abstract Results are presented of calculations on the generation of residual vorticity by tidal currents over the bottom topography of the Southern Bight of the North Sea. A typical order of magnitude is 10?6 to 10?7 s ?1. This is compared with current measurements on calm days, when similar magnitudes are found. At windspeeds less than about 5 m/s tidal generation of residual vorticity is important; at higher windspeeds wind effects begin to dominate. Our results are relevant in understanding the spatial variability of residual currents, because a non-zero vorticity implies the existence of horizontal gradients in the residual current field. 相似文献
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Bioremediation of Phenanthrene by Mycoplana sp. MVMB2 Isolated from Contaminated Soil 总被引:1,自引:0,他引:1
Mahalingam Brinda Lakshmi Venkataramagounder Perumal Anandaraj Manickam Velan 《洁净——土壤、空气、水》2013,41(1):86-93
The effect of nutrient and surfactant addition on the biodegradation of phenanthrene was studied in a batch scale soil–slurry system using isolated Mycoplana sp. MVMB2strain. The study was conducted using an artificially phenanthrene spiked and as well as contaminated soil from petrochemical industrial site. Maximum phenanthrene degradation and subsequent high microbial growth were observed at optimum pH (pH 6) and C/N/P ratio (100:20:3). To investigate maximum substrate degradation potential of Mycoplana sp. MVMB2, very high concentrations of phenanthrene (50–200 mg/kg soil) were used. The organism was capable of degrading >60% for a concentration below 20 mg/kg soil and >40% for concentrations up to 200 mg/kg within 8 days. Further the influence of five different surfactants namely Span 80, Tween 20, Triton X‐100, cetyl trimethyl ammonium bromide, and sodium dodecyl sulfate were tested at their critical micelle concentration (CMC) levels for phenanthrene degradation in the soil. The addition of surfactant enhanced the biodegradation and a maximum of 84.49% was obtained for Triton X‐100. Complete phenanthrene degradation by Mycoplana sp. MVMB2 was observed at 3 CMC concentration of Triton X‐100. The optimized parameters obtained were used for the degradation of phenanthrene present in the contaminated soil and 98.6% biodegradation was obtained. Thus, the results obtained in the study suggested that biodegradation of phenanthrene by Mycoplana sp. MVMB2 appeared to be feasible to remediate phenanthrene rich contaminated sites. 相似文献
78.
西昆仑山前东段的和田-柯克亚构造带与塔里木盆地内的麻扎塔格构造带相距为200 km,两者近似平行,遥相对应,麻扎塔格构造带是和田-柯克亚构造带的前沿,山前挤压变形量沿古近系阿尔塔什组膏泥岩向北传递约200 km到麻扎塔格,形成往北东逆冲的断层传播褶皱,在盆地腹部表现为一条显著的北西向地形隆起。因此,整个西昆仑山前东段新生代褶皱冲断带宽约为270 km,长约为220 km,由和田-柯克亚构造带、麦盖提斜坡和麻扎塔格构造带组成。中部近200 km的麦盖提斜坡内没有明显构造变形,且整个褶皱冲断带的锥形楔角度远小于活动造山带的临界锥形角,说明古近系底部阿尔塔什组膏泥岩以及新生代沉积体的形态是这个褶皱冲断带锥形楔形成的主控原因,膏泥岩控制了锥形楔的顶面坡度α基底构造形态及上覆沉积楔形体则控制了锥形楔的底部滑脱层倾角β。 相似文献
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Critical adaptation to hurricanes in the Mexican Caribbean: Development visions, governance structures, and coping strategies 总被引:1,自引:0,他引:1
David Manuel-Navarrete Mark Pelling Michael Redclift 《Global Environmental Change》2011,21(1):249-258
The need to tackle climate hazards and development efforts simultaneously is widely acknowledged. However, the possibility of alternative visions of development is seldom contemplated. Instead, adaptation research usually assumes monolithic claims about development constructed from the status quo of global capitalism. This paper outlines a critical approach to adaptation and explores the interplay between visions of development, governance structures, and strategies to cope with hurricanes in the Mexican Caribbean, a region at the ‘front line’ of both globalization and climatic extreme phenomena. Critical adaptation formulates the experiencing of hazards as essentially political and tied to contingent development paths, which may eventually become hegemonic. Over a hundred semi-structured and open interviews were held in Cancun, Mahahual, Playa del Carmen, and Tulum including academics, businesspeople, bureaucrats, journalists, non-governmental organizations and tourism workers in order to characterize development visions in the Mexican Caribbean. Findings show a prevalent hegemonic vision supporting mass tourism growth which encourages hurricane coping strategies based on effective evacuation and attracting investments for rapid economic recovery. The actual implementation of this vision increases social inequalities, degrades ecosystems, and amplifies overall exposure to extreme events. Mass tourism is enforced by undemocratic governance structures sustained by a coalition of government and tourism corporations (a government-capital bloc in Gramsci's sense). Some weak signs of counter-hegemony were identified in Playa del Carmen, Tulum and Mahahual. These isolated episodes of resistance might have triggered alternative coping strategies despite having little effect in altering the overall course of development. Further critical research is needed to unveil the socio-political foundations of development visions and their influence on capacities to cope with climatic extreme events. 相似文献
80.
This study investigates the mechanism of formation of convection plumes of mushroom shape in sub-solidus mantle and their prediction.The seismic-tomographic images of columnar structures of several hundreds kilometers in diameter have been reported by several researchers,while the much cherished mushroom-shaped plume heads could only be found in computational geodynamics(CGD) models and simple small-scale laboratory analogue simulations.Our theory of transient instability shows that the formation of conv... 相似文献