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1.
China and India together have more than one third of the world population and are two emerging economic giants of the developing world now experiencing rapid economic growth, urbanization, and motorization. The urban transportation sector is a major source of carbon dioxide (CO2) emissions in China and India. The goal of this study is to analyze the characteristics and factors of CO2 emissions produced by commuters in Chinese and Indian cities and thus to identify strategies for reducing transportation CO2 emissions and mitigating global climate change. Xi’an in China and Bangalore in India were chosen as two case study cities for their representativeness of major cities in China and India. The trends of CO2 emissions produced by major traffic modes (electric motors, buses, and cars) in major cities of China and India were predicted and analyzed. The spatial distributions of CO2 emissions produced by commuters in both cities were assessed using spatial analysis module in ArcGIS (Geographic Information System) software. Tobit models were then developed to investigate the impact factors of the emissions. The study has several findings. Firstly, in both cities, the increase of vehicle occupancy could reduce commuting CO2 emissions by 20 to 50 % or conversely, if vehicle occupancy reduces, an increase by 33.33 to 66.67 %. It is estimated that, with the current increasing speed of CO2 emissions in Xi’an, the total CO2 emissions from electric motors, buses, and cars in major cities of China and India will be increased from 135?×?106 t in 2012 to 961?×?106 t in 2030, accounting for 0.37 to 2.67 % of the total global CO2 emissions of 2013, which is significant for global climate change. Secondly, households and individuals in the outer areas of both cities produce higher emissions than those in the inner areas. Thirdly, the lower emissions in Xi’an are due to the higher density and more compact urban pattern, shorter commuting distances, higher transit shares, and more clean energy vehicles. The more dispersed and extensive urban sprawl and the prevalence of two-wheeler motorbikes (two-wheeler motorbike is abbreviated as “two-wheeler” in the following sections) fueled by gasoline cause higher emissions in Bangalore. Fourthly, car availability, higher household income, living outside the 2nd or Outer Ring Road, distance from the bus stop, and working in the foreign companies in Bangalore are significant and positive factors of commuting CO2 emissions. Fifthly, “70-20” and “50-20” (this means that generally, 20 % of commuters and households produce 70 % of total emissions in Xi’an and 20 % of commuters and households produce 50 % of total emissions in Bangalore) emission patterns exist in Xi’an and Bangalore, respectively. Several strategies have been proposed to reduce urban CO2 emissions produced by commuters and further to mitigate global climate change. Firstly, in the early stage of fast urbanization, enough monetary and land investment should be ensured to develop rail transit or rapid bus routes from outer areas to inner areas in the cities to avoid high dependency on cars, thus to implement the transit-oriented development (TOD), which is the key for Chinese and Indian cities to mitigate the impact on global climate change caused by CO2 emissions. Secondly, in Bangalore, it is necessary to improve public transit service and increase the bus stop coverage combined with car demand controls along the ring roads, in the outer areas, and in the industry areas where Indian foreign companies and the governments are located. Thirdly, Indian should put more efforts to provide alternative cleaner transport modes while China should put more efforts to reduce CO2 emissions from high emitters.  相似文献   

2.
The lower troposphere is an excellent receptacle, which integrates anthropogenic greenhouse gases emissions over large areas. Therefore, atmospheric concentration observations over populated regions would provide the ultimate proof if sustained emissions changes have occurred. The most important anthropogenic greenhouse gas, carbon dioxide (CO(2)), also shows large natural concentration variations, which need to be disentangled from anthropogenic signals to assess changes in associated emissions. This is in principle possible for the fossil fuel CO(2) component (FFCO(2)) by high-precision radiocarbon ((14)C) analyses because FFCO(2) is free of radiocarbon. Long-term observations of (14)CO(2) conducted at two sites in south-western Germany do not yet reveal any significant trends in the regional fossil fuel CO(2) component. We rather observe strong inter-annual variations, which are largely imprinted by changes of atmospheric transport as supported by dedicated transport model simulations of fossil fuel CO(2). In this paper, we show that, depending on the remoteness of the site, changes of about 7-26% in fossil fuel emissions in respective catchment areas could be detected with confidence by high-precision atmospheric (14)CO(2) measurements when comparing 5-year averages if these inter-annual variations were taken into account. This perspective constitutes the urgently needed tool for validation of fossil fuel CO(2) emissions changes in the framework of the Kyoto protocol and successive climate initiatives.  相似文献   

3.
Although stable isotope ratios in animals have often been used as indicators of the trophic level and for the back-calculation of diets, few experiments have been done under standardized laboratory conditions to investigate factors influencing 15N and 13C values. An experiment using Nile tilapia [Oreochromis niloticus (L.)] was therefore carried out to test the effect of different dietary protein contents (35.4, 42.3, and 50.9%) on 15N and 13C values of the whole tilapia. The fish were fed the isoenergetic and isolipidic semi-synthetic diets at a relatively low level. 15N and 13C values of the lipid-free body did not differ between the fish fed the diets with different protein contents, but the trophic shift for N and C isotopes decreased with increasing protein accretion in the individual fish, for N from 6.5 to 4 and for C in the lipid-free body from 4 to 2.5. This is the first study showing the strong influence of the individual protein balance to the degree to which the isotopic signature of dietary protein was modified in tissue protein of fish. The extrapolation of the trophic level or the reconstruction of the diet of an animal from stable isotope ratios without knowledge of the individual physiological condition and the feeding rate may lead to erroneous results.  相似文献   

4.
海伦·伊丽莎白·克拉克(Helen Elizabeth Clark),1950年2月26日出生于新西兰哈密尔顿市。她早年就读于提帕胡小学、奥克兰爱普松女子语言学校,后在奥克兰大学攻读文学学士和文学硕士学位,于1976年获得大学格兰特委员会奖学金,随后出国留学,之后在奥克兰大学政治系执教8年。  相似文献   

5.
6.
胡利娅·卡拉维亚斯·利略。墨西哥前环境、资源和渔业部部长,墨西哥国立自治大学生物学教授。卡拉维亚斯教授1954年出生于墨西哥城,在墨西哥国立自治大学获得学位后留校教授环境科学并从事热带雨林保护、自然资源管理和环境保护方面的研究。  相似文献   

7.
Flower colour is an important signal used by flowering plants to attract pollinators. Many anthophilous insects have an innate colour preference that is displayed during their first foraging bouts and which could help them locate their first nectar reward. Nevertheless, learning capabilities allow insects to switch their colour preferences with experience and thus, to track variation in floral nectar availability. Manduca sexta, a crepuscular hawkmoth widely studied as a model system for sensory physiology and behaviour, visits mostly white, night-blooming flowers lacking UV reflectance throughout its range in the Americas. Nevertheless, the spectral sensitivity of the feeding behaviour of naïve moths shows a narrow peak around 450 nm wavelengths, suggesting an innate preference for the colour blue. Under more natural conditions (i.e. broader wavelength reflectance) than in previous studies, we used dual choice experiments with blue- and white-coloured feeders to investigate the innate preference of naïve moths and trained different groups to each colour to evaluate their learning capabilities. We confirmed the innate preference of M. sexta for blue and found that these moths were able to switch colour preferences after training experience. These results unequivocally demonstrate that M. sexta moths innately prefer blue when presented against white flower models and offer novel experimental evidence supporting the hypothesis that learning capabilities could be involved in their foraging preferences, including their widely observed attraction to white flowers in nature.  相似文献   

8.
Blood-sucking leeches have been used for medical purposes in humans for hundreds of years. Accordingly, one of the most prominent species has been named Hirudo medicinalis by Carl Linne in 1758. Feeding on vertebrate blood poses some serious problems to blood-sucking ectoparasites, as they have to penetrate the body surface of the host and to suppress the normal reactions of the host to such injuries (swelling, pain, inflammation) to remain undetected during the feeding period. Furthermore, the parasites have to take measures to inhibit the normal reactions in host tissues to blood vessel damage, namely hemostasis and blood coagulation (platelet aggregation and activation, activation of thrombin and formation of fibrin clots). During evolution, leeches have acquired the ability to control these processes in their hosts by transferring various bioactive substances to the host. These substances are supposedly produced in unicellular salivary gland cells and injected into the wound at the feeding site through tiny salivary ductule openings in the jaws that the leech uses to slice open the host body surface and to cut blood vessels in the depth of the wound. This review summarizes current knowledge about the salivary gland cells and the biological effects of individual saliva components as well as hints to the potential usefulness of some of these compounds for medical purposes.  相似文献   

9.
A three-dimensional, iron-cemented structure found in the anterior thoracic cavity of articulated Thescelosaurus skeletal remains was hypothesized to be the fossilized remains of the animal’s four-chambered heart. This was important because the finding could be interpreted to support a hypothesis that non-avian dinosaurs were endothermic. Mammals and birds, the only extant organisms with four-chambered hearts and single aortae, are endotherms. The hypothesis that this Thescelosaurus has a preserved heart was controversial, and therefore, we reexamined it using higher-resolution computed tomography, paleohistological examination, X-ray diffraction analysis, X-ray photoelectron spectroscopy, and scanning electron microscopy. This suite of analyses allows for detailed morphological and chemical examination beyond what was provided in the original work. Neither the more detailed examination of the gross morphology and orientation of the thoracic “heart” nor the microstructural studies supported the hypothesis that the structure was a heart. The more advanced computed tomography showed the same three areas of low density as the earlier studies with no evidence of additional low-density areas as might be expected from examinations of an ex situ ostrich heart. Microstructural examination of a fragment taken from the “heart” was consistent with cemented sand grains, and no chemical signal consistent with a biological origin was detected. However, small patches of cell-like microstructures were preserved in the sandstone matrix of the thoracic structure. A possible biological origin for these microstructures is the focus of ongoing investigation.  相似文献   

10.
周娟  张硕新  陈斌 《环境保护》2011,(14):46-47
河南新乡的个体户田桂荣从1999年开始发起了回收废电池的活动,几百个废电池回收箱,几万份传单,随着坚持不懈的努力和人们环保意识的增强,她得到了越来越多的理解和和支持,废电池回收量日渐增长.然而,麻烦也来了:"这么多废电池到底咋办?真是难死我了!谁能告诉我处理废电池的好办法?"她这样说. 其实受此网扰的绝不只是田桂荣,废电池的回收利用一直是个难题.废电池有毒,不能乱扔,这大家都知道.于是很多学校、机关、商店都开展了废电池回收活动.但没过多久,各地的活动就陷入困境,因为收上来的废电池找不到出路,堆积如山,反成了负担……  相似文献   

11.
比尔·金     
比尔·金先生(通常大家叫他Bill)现在是TNC(大自然保护协会)副总裁、全球首席生态保护执行官,统管TNC的全球保护事务(下设9大部门,涉及32个国家),并负责推动机构最重要的保护项目和保护策略。比尔·金在TNC任职已经超过12年,曾在机构内担任过多个重要的领导职务。  相似文献   

12.
斯塔夫罗·迪马斯,欧盟环境专员,生于1941年4月,早年就读于雅典大学并取得法律与经济学学士学位,后在美国纽约大学取得法律硕士学位。1977年至2004年间,他曾作为新民主党代表连续十次被选为国会议员并且在希腊政坛处于领导地位,先后出任贸易部长、新民主党国会发言人、农业部长、工业能源及科技部长和新民主党秘书长等重要职位。  相似文献   

13.
洗涤之"伤"     
向熠 《环境》2011,(1):91-93
毫无疑问,洗涤剂为个人保健和家居保洁提供了帮助,成为许多家庭的必备品。但这些洗涤剂潜在的化学危害却常常被人忽略。  相似文献   

14.
Genetic variability among males is a necessary precondition for the evolution of female choice based on indirect genetic benefits. In addition to mutations and host–parasite cycles, migration of locally adapted individuals offers an explanation for the maintenance of genetic variability. In a previous study, conducting a reciprocal transplant experiment on a grasshopper, Chorthippus biguttulus, we found that environmental conditions significantly influenced not only body condition but also an important trait of male calling song, the amplitude of song. Although not significant, all other analysed physical and courtship song traits and attractiveness were superior in native than in transferred males. Thus, we concluded that local adaptation has a slight but consistent influence on a range of traits in our study populations, including male acoustic attractiveness. In our present study, we scanned male grasshoppers from the same two populations for amplification fragment length polymorphism (AFLP) loci connected with acoustic attractiveness to conspecific females. We found greater differences in allele frequencies between the two populations, for some loci, than are expected from a balance between drift and gene flow. These loci are potentially connected with locally adapted traits. We examined whether these alleles show the proposed genotype environment interaction by having different associations with attractiveness in the two populations. One locus was significantly related to sexual attractiveness; however, this was independent of the males’ population affiliation. Future research on the evolution of female choice will benefit from knowledge of the underlying genetic architecture of male traits under intraspecific sexual selection, and the ‘population genomics’ approach can be a powerful tool for revealing this structure.  相似文献   

15.
自然·水·人   总被引:5,自引:0,他引:5  
人类社会向前发展,人向自然界的索取不断增加,对自然的干扰也逐步加剧,致使自然界的承受能力受到影响,人与自然的关系出现紧张。为此,人必须处理好与自然的关系,以免人的生存环境受到威胁。水是自然界的重要因素,和人的生存与人类社会的发展关系密切。由于用水量不断增加和用水不当,一些地区出现水资源危机,人在和水旱灾害进行抗争中,也出现了由于措施不当带来的人为加大灾害的问题。因此,人必须在处理好与自然关系的框架中,认真处理好与水的关系,以保障水资源的永续利用和人类社会的可持续发展。  相似文献   

16.
Terrestrial salamanders of the genus Salamandra represent one of the most prominent groups of amphibians. They are mainly distributed across Europe but also reach Northern Africa and the Near East. Members of the six currently accepted species have long been known to be poisonous; however, work on their toxins was mostly published in German language, and therefore, many nuances of these studies have remained hidden from the majority of herpetologists and toxinologists. Several Salamandra species are called fire salamanders due to their highly contrasted, black-yellow colouration which probably serves to deter predators, although thorough evidence for aposematism in Salamandra is still lacking. Salamandra skin toxins do not only represent a potent antipredator defence but may also have antimicrobial effects. A better understanding of this dual function of Salamandra skin secretions is of utmost importance in the face of the emergence of a fungal disease causing catastrophic declines of fire salamanders in Central Europe, caused by the fungus Batrachochytrium salamandrivorans. In this review, we summarize the knowledge on Salamandra toxins, providing a list of the compounds so far isolated from their secretion and focusing on the bioactivity of the major compounds in Salamandra secretions, the steroidal alkaloids. We identify priorities for future research, including a screening of co-occurrence of steroidal alkaloids and tetrodotoxins in salamandrids, chemical characterization of already identified novel steroidal compounds, elucidation of the presence and role of peptides and proteins in the secretion, and experimental in vitro and in vivo study of the interactions between bioactive compounds in Salamandra skin secretions and cutaneous fungal and bacterial pathogens.  相似文献   

17.
弗朗西丝·拜内克,现任美国自然资源保护委员会(NRDC)主席。弗朗西丝在耶鲁大学获得学士学位。并获耶鲁大学森林与环境研究学院硕士学位。自1973年以来,弗朗西斯已经在NRDC工作了30多年,2006年成为主席之前,她担任该组织的执行总监8年,期间NRDC的成员达到300多个,比之前增加了一倍。  相似文献   

18.
夏光 《环境保护》2011,(7):11-13
2011年是十二五的开局之年,这其中的局字深有含义,它说明人们把未来五年看作是一个有序安排的局,是一个经过系统构思的整体,而非任其自然的时间过程。  相似文献   

19.
"十一五"时期是我国发展史上极不平凡的五年,也是环境保护事业大有作为的五年.五年来,我国将主要污染物减排作为国民经济和社会发展规划的约束性指标,着力解决影响可持续发展和损害群众健康的突出环境问题,环境保护从认识到实践发生重要变化,环境保护事业不断发展,环境质量稳步改善.  相似文献   

20.
奈杰尔·布兰顿教授,英国皇家工程学会会员、皇家特许工程师、英国能源学会会员、英国材料、矿石和冶金协会会员以及英国伦敦城市行业协会会员。主要从事燃料电池技术的发展与应用研究。布兰顿毕业于伦敦帝国理工学院,获电化学工程理学学士学位及博士学位。  相似文献   

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