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221.
ABSTRACT

Smart and eco-cities have become important notions for thinking about urban futures. This article contributes to these ongoing debates about smart and eco-urbanism by focussing on recent urbanisation initiatives in Asia. Our study of India’s Smart Cities Mission launched under the administration of Narendra Modi and China’s All-In-One eco-cities project initiated by Xi Jinpin unfolds in two corresponding narratives. Roy and Ong’s [2011. Worlding Cities: Asian Experiments and the Art of Being Global. Oxford: Wiley-Blackwell] “worlding cities” serves as the theoretical backdrop of our analysis. Based on a careful review of a diverse set of academic literature, policy and other sources we identify five process-dimensions for analysing the respective urban approaches. We show how the specific features of China’s and India’s urban focus, organisation, implementation, governance and embedding manifest both nations’ approaches to smart and eco-urbanism. We argue that India’s Smart City Mission and China’s All-in-One project are firmly anchored in broader agendas of change that are set out to transform the nation and extend into time. The Indian Smart City Mission is part of a broader ambition to transform the nation enabling her “smart incarnation” in modernity. Smart technologies are seen as the key drivers of change. In China the framework of ecological civilisation continues a 5000-year historical tradition of civilisation excellence. By explicitly linking eco-urbanism to the framework, eco-cities become a means to enact ecological civilisation on the (urban) ground.  相似文献   
222.
Organisms sensitive to ambient environment are used as bioindicators in monitoring pollution. The present investigation is designed to measure the extent of mercury and organomercury levels in selective biota of different trophic levels inhabiting in the coastal environment of Sunderban Biosphere Reserve, eastern part of India. The primary objective of this work is to provide baseline data for future environmental quality programme and to ascertain the suitability of these organisms to be used as bioindicator species of pollution. The seagrass (Porterasia coarctata), macrobenthos (polychaetes, gastropods and bivalve molluscs) and pelagic finfishes were collected from sites of different physiochemical characteristics. Concentration of total mercury was determined by cold vapour atomic absorption spectrophotometry technique (CVAAS) using a Perkin-Elmer 2380 AAS equipped with MHS 10.Both mercury and organomercury levels showed considerable interspecific and regional variations which reflected the feeding strategy of these animals and also the location of stations. The bivalve molluscs showed a high degree of organ-specificity in accumulation which might be attributed to the ion exchange activity of mucous membrane covering gill and mantle. Mercury levels in various compartments did not reveal any regular temporal variations but showed a slight increase in the late monsoon months indicating the apparent influence of river run-off and reduction in salinity in the ambient medium. A continuous monitoring programme is recommended in order to clarify the present trend and to establish the studied organisms as indicator species.  相似文献   
223.
1951-2008年东北地区水分盈亏量时空格局   总被引:9,自引:0,他引:9  
基于1951-2008年东北地区106个气象站点的实测数据,利用Penman-Monteith公式计算潜在蒸散量,并将气候水分盈亏量表示为同期降水量与潜在蒸散量之差。最后,通过Kendall秩次相关趋势分析、Morlet小波函数、Mann-Kendall突变检验等方法探讨了东北地区水分盈亏量的时空变化特征。结果表明:①1951-2008年,东北地区多年平均水分盈亏量在-850~650 mm之间变化,呈自东向西、自北向南、自东北向西南逐渐减少的空间变化趋势;②东北地区106个气象站点中有97个站点的水分盈亏量呈下降趋势,其中28个站点的下降趋势能通过P<0.05的显著性检验;③全区平均、海拉尔、长春、宽甸年际波动明显,多年平均值依次为-283.60、-427.25、-362.58、334.91 mm,四者的水分盈亏量年内分配不均匀,最小值出现在5月,最大值出现在7-8月;④水分盈亏量存在周期结构性,偏高期、偏低期交替出现,全区平均、海拉尔、长春、宽甸的第一主周期依次为26、28、25、9 a,水分盈亏量还具有突变特征,全区平均在1999年发生了一次减少突变,长春在1958、1998年各发生了一次减少突变。  相似文献   
224.
1961-2006年东北地区农业气候资源变化特征   总被引:6,自引:0,他引:6  
应用1961-2006年中国东北三省72个气象台站的气象资料,统计分析了东北三省稳定农耕期、生长期及积温、降水量、日照时数农业气候资源的变化特征,结果表明:研究期间,东北三省平均农耕期、生长期分别延长了2.4 d·10 a-1、2.3 d·10 a-1;经Mann-Kendall检验,农耕期长度、生长期长度分别在1988年、1992年发生突变。46 a东北三省积温表现为一致的增多趋势,降水量、日照时数呈减少趋势。分析比较突变年前后两个时段的农业气候资源变化,农耕期、生长期平均积温高值区向东、向北扩展;农耕期降水量高值区、低值区面积萎缩,中值区向东南方向扩张,生长期降水量中高值区面积减少;农耕期平均日照时数呈现高值区、低值区面积减少,而生长期日照时数呈现高值区、低值区面积增大的特点。  相似文献   
225.
In view of the increasing interest in the development and dissemination of technologies for harnessing new and renewable sources of energy in India, there have also been some efforts towards their use in the domestic lighting sector. However, the cumulative number of Solar Photovoltaic (SPV) lighting systems such as SPV lanterns and solar home lighting systems in India is far below their theoretical potential despite government subsidy programmes. One of the major barriers is the high capital investment in these systems. The Clean Development Mechanism (CDM) provides industrialized countries with an incentive to invest in emission reduction projects in developing countries to achieve a reduction in CO2 emissions at lowest cost that also promotes sustainable development in the host country. SPV lanterns and solar home lighting systems could be of interest under the CDM because they directly displace greenhouse gas emissions while contributing to sustainable rural development. However, only two SPV projects have been submitted under the CDM so far. This study assesses the maximum theoretical as well as the realistically achievable CDM potential of SPV lanterns and solar home lighting systems in India. The SPV lantern project is financially viable at a certified emissions reductions (CER) price of 34 € whereas the solar home lighting project is financially viable at a CER price of 46 €. While the maximum mitigation volume is about 35 million tonne CO2 on an annual basis, an estimate of achievable CER levels is done using the past diffusion trends of SPV systems. We find that annual CER volumes could reach 0.8 to 2.4 million by 2012 and 5.6 to 13.6 million by 2020. This would require that the government sets the subsidy level for SPV lighting systems at a level that allows them to become viable with the CER revenue. From a macro-economic point of view this makes sense if the sustainability benefits are deemed sufficiently high to warrant promotion of this type of project.
Axel MichaelowaEmail:
  相似文献   
226.
Organochlorine pesticides (OCPs) are an important potential component of chemical pollutants used extensively for agriculture and sanitation purposes in India as these are comparatively cheap and effective. These persistent organic compounds such as HCH isomers, DDT and its metabolites are the predominant chemical contaminants found along the Indian coast and thus constitute both alluring and grave areas of scientific research. Our objective in the paper is to provide a comprehensive account of the distribution of organochlorine pesticides in biotic and abiotic compartments of the Indian coastal environment, make some comments on their environmental sources, their movement through the food chain and possible ecotoxicological risk of health in biota including humans. The prevalent HCH, DDT and HCB concentrations differ markedly in eastern and western coast of India reflecting differing agricultural and other usage and their ultimate input into the coastal environment by several rivers and the bioturbation activities of macrozoobenthos (bivalve mollusks, polychaetous annelids, etc.). In several cases, the DDT levels exceeded the effects range-low (ER-L) and could thus cause acute biological impairments, in comparison with the sediment quality guidelines. Contributions of DDT metabolites (DDT, DDD and DDE residues) vary in different Indian coastal regions predominated by pp'-DDT and pp'-DDD. Measured concentrations of HCHs were lower than DDTs that might be due to higher water solubility, vapor pressure and biodegradability of the latter. HCH and DDT residues in fish in India were lower than those in the temperate countries indicating a lower accumulation in tropical fish, which might be related to rapid volatilization of this insecticide in the tropical environment. The concentrations of other chlorinated pesticides (aldrin, dieldrin, eldrin, methoxychlor, endosulfan sulphate) were lower and not generally of great concern.  相似文献   
227.
东北地区参考蒸散量的变化特征及其成因分析   总被引:6,自引:0,他引:6  
蒸散是水分运动过程中地表热量平衡和水分平衡的组成部分,是影响气候变化的重要一项。进行蒸散量变化的研究,对了解气候变化、探讨水分循环变化规律具有十分重要的意义。论文利用东北地区124个气象站1961—2007年的日气象数据,采用Penman-Monteith方程计算了参考蒸散量,分析了参考蒸散量的变化趋势及其变化原因。结果表明,在这47 a间,东北地区年平均气温以0.38℃/(10 a)的趋势递增,但是参考蒸散量总体上却以4.4 mm/(10 a)的速度递减。在地区分布上,三分之二的地区参考蒸散量呈下降趋势,显著下降的地区集中在辽宁朝阳地区,三分之一的地区参考蒸散量呈上升趋势,主要集中在辽宁南部和吉林东部地区。对有关各气象因子分析表明,影响参考蒸散量的主要因子为日照时数和风速。  相似文献   
228.
Urban parks in India are often discussed as positive environmental projects, and their creation appears as unproblematic in public discourse. This paper presents the creation of a municipal park in a small city in Gujarat, India. Using insights from history and architecture, we stress the importance of reading parks as political and to some extent ideological projects in the larger context of city-making. The political ecology and history of the particular park studied here allow us to problematise the socio-ecological project of urban “beautification” via park creation. The municipal park, established in the centre of a small urban agglomeration after displacing a slum settlement from the site, is – as we argue – an integral part of a local geography of power. As such it expresses several registers of values upheld by local elites and brings into focus highly conflictive social relations. The case study contributes to further developing a situated urban political ecological approach that starts theorising cities from the South. It moreover offers a critical perspective on the understudied urban nature of small towns.  相似文献   
229.
This study tests the thesis that ‘vulnerability to climate change is not only a result of biophysical events alone but also influenced by the socioeconomic conditions in which climate change occurs’. The study chose Uttar Pradesh (UP), a state in India, for its importance in the nation's food and nutrition security programme and its high sensitivity to climate change. It uses an indicator approach to see which districts of UP are the most vulnerable to climate change, and attempts to identify the factors on a set of explanatory variables. The study finds that infrastructurally and economically developed districts are less vulnerable to climate change; in other words, vulnerability to climate change and variability is linked with social and economic development. This observation is corroborated by the findings of relational analysis wherein livestock, forestry, consumption of fertilizer, per capita income, and infant mortality rate are observed to be important correlates of vulnerability to climate change.  相似文献   
230.
The rate of degradation of forchlorfenuron, a cytokinin-based plant growth regulator (PGR) was explored in typical grapevine soils of India with simultaneous evaluation of its effect on biochemical attributes of the test soils in terms of the activities of specific soil microbial enzymes. In all the test soils, namely clay, sandy-loam and silty-clay, the dissipation rate was faster at the beginning, which slowed down with time, indicating a non-linear pattern of degradation. Degradation in soils could best be explained by two-compartment 1st + 1st order kinetics with half-life ranging between 4–10 days. The results suggest that organic matter might be playing a major role in influencing the rate of degradation of forchlorfenuron in soil. The rate of degradation in sandy-loam soil was fastest followed by clay and silty-clay soils, respectively. Comparison of the rate of degradation in natural against sterilized soils suggests that microbial degradation might be the major pathway of residue dissipation. Changes in soil enzyme activities as a consequence of forchlorfenuron treatment were studied for extra-cellular enzymes namely acid phosphatase, alkaline phosphatase and β -glucosidase and intracellular enzyme-dehydrogenase. Although small changes in enzyme activities were observed, forchlorfenuron did not have any significant deleterious effect on the enzymatic activity of the test soils. Simple correlation studies between degradation percentage and individual enzyme activities did not establish any significant relationships. The pattern and change of enzyme activity was primarily the effect of the incubation period rather than the effect of forchlorfenuron itself.  相似文献   
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