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1.

Purpose  

As liquid crystal display (LCD) flat-screen televisions increase in popularity, their potential contribution to global warming has received wide attention. This study presents global warming impacts resulting from the life cycle assessment (LCA) of LCD flat-screen televisions for key global warming contributors from the “cradle-to-gate” and use stages of the product’s life cycle. The emissions from nitrogen trifluoride (NF3), a greenhouse gas with a global warming potential (GWP) 17,000 times more potent than carbon dioxide (CO2), are not monitored in the Kyoto Protocol. Emissions in the cradle-to-gate and use stages were modeled in this study according to their GWP (kg CO2 equivalent), focusing and analyzing the most significant source of NF3 emissions.  相似文献   

2.
We assess climate impacts of global warming using ongoing observations and paleoclimate data. We use Earth’s measured energy imbalance, paleoclimate data, and simple representations of the global carbon cycle and temperature to define emission reductions needed to stabilize climate and avoid potentially disastrous impacts on today’s young people, future generations, and nature. A cumulative industrial-era limit of ∼500 GtC fossil fuel emissions and 100 GtC storage in the biosphere and soil would keep climate close to the Holocene range to which humanity and other species are adapted. Cumulative emissions of ∼1000 GtC, sometimes associated with 2°C global warming, would spur “slow” feedbacks and eventual warming of 3–4°C with disastrous consequences. Rapid emissions reduction is required to restore Earth’s energy balance and avoid ocean heat uptake that would practically guarantee irreversible effects. Continuation of high fossil fuel emissions, given current knowledge of the consequences, would be an act of extraordinary witting intergenerational injustice. Responsible policymaking requires a rising price on carbon emissions that would preclude emissions from most remaining coal and unconventional fossil fuels and phase down emissions from conventional fossil fuels.  相似文献   

3.
Human energy     
In the midst of big-oil record profits and growing debate on global warming, the Chevron Corporation launched its “Human Energy” public relations campaign. In television commercials and print advertisements, Chevron portrays itself as a compassionate entity striving to solve the planet’s energy crisis. Yet, the first term in this corporate oxymoron misleadingly reframes the significance of the second, suggesting that the corporation has a renewed focus. In depicting Chevron as a green/human organization, the “Human Energy” campaign obscures from view the corporation’s more unsightly products, policies, and practices. Reflection, however, on our own complicity in sustaining energy corporations and their activities undermines binary thinking and signals that the compulsion to denounce is insufficient. This article explores Chevron’s media campaign and one organized reaction to it. This counter-campaign both redeployed Chevron’s imagery and underscored our collusion and responsibility—tactics seeking to loosen the taut inevitability-of-oil story at Chevron’s core.  相似文献   

4.
This essay argues that what makes “global health” “global” has more to do with configurations of space and time, and the claims to expertise and moral stances these configurations make possible, than with the geographical distribution of medical experts or the universal, if also uneven, distribution of threats to health. Drawing on a study of public–private partnerships supporting Botswana’s HIV/AIDS treatment program, this essay demonstrates ethnographically the processes by which “global health” and its quintessential spaces, namely “resource-limited” or “resource-poor settings,” are constituted, reinforced, and contested in the context of medical education and medical practice in Botswana’s largest hospital. Using Silverstein’s work on orders of indexicality, I argue that the terms of “global health” are best understood as chronotopic, and demonstrate how actors orient themselves and others spatio-temporally, morally, and professionally by using or refuting those terms. I conclude by arguing that taking “global health” on its own terms obscures the powerful forces by which it becomes intelligible. At stake are the frames within which medical anthropologists understand their objects of study, as well as the potential for the spaces of “global health” intervention to expand ever outward as American medical personnel attempt to calibrate their experiences to their expectations.  相似文献   

5.
Reconsideration of the term “gene” should take into account (a) the potential clash between hierarchical levels of information discussed in the 1970s by Gregory Bateson, (b) the contrast between conventional and genome phenotypes discussed in the 1980s by Richard Grantham, and (c) the emergence in the 1990s of a new science—Evolutionary Bioinformatics—that views genomes as channels conveying multiple forms of information through the generations. From this perspective, there is conceptual continuity between the functional “gene” of Mendel and today’s GenBank sequences. If the function attributed to a gene can change specifically as the result of a DNA mutation, then the mutated part of DNA can be considered as part of the gene. Conversely, even if appearing to locate within a gene, a mutation that does not change the specific function is not part of the gene, although it may change some other function to which the DNA sequence contributes. This strict definition is impractical, but serves as a guide to more workable, context-dependent, definitions. The gene is either (1) The DNA sequence that is transcribed, (2) The latter plus the immediate 5′ and 3′ sequences that, when mutated, specifically affect the function, (3) The latter two, plus any remote sequences that, when mutated, specifically affect the function. Attempts, such as that of Scherrer and Jost, to redefine Mendel’s “gene,” may be too narrowly focused on regulation to the exclusion of other important themes.  相似文献   

6.
For many ecosystem services, it remains uncertain whether the impacts of climate change will be mostly negative or positive and how these changes will be geographically distributed. These unknowns hamper the identification of regional winners and losers, which can influence debate over climate policy. Here, we use coral reefs to explore the spatial variability of climate stress by modelling the ecological impacts of rising sea temperatures and ocean acidification, two important coral stressors associated with increasing greenhouse gas (GHG) emissions. We then combine these results with national per capita emissions to quantify inequities arising from the distribution of cause (CO2 emissions) and effect (stress upon reefs) among coral reef countries. We find pollution and coral stress are spatially decoupled, creating substantial inequity of impacts as a function of emissions. We then consider the implications of such inequity for international climate policy. Targets for GHG reductions are likely to be tied to a country's emissions. Yet within a given level of GHG emissions, our analysis reveals that some countries experience relatively high levels of impact and will likely experience greater financial cost in terms of lost ecosystem productivity and more extensive adaptation measures. We suggest countries so disadvantaged be given access to international adaptation funds proportionate with impacts to their ecosystem. We raise the idea that funds could be more equitably allocated by formally including a metric of equity within a vulnerability framework.  相似文献   

7.
刘慧雅  王铮  马晓哲 《生态学报》2011,31(15):4405-4414
以云南省为例,用马尔科夫链计算能源结构,在经济增长模型基础上基于动态最优化理论估计能源消费碳排放,并基于CO2FIX模型计算云南省森林碳汇,预测在能源消费碳排放和森林碳汇共同作用下的从2008到2050年碳净排放量。研究发现云南省能源消费碳排放量和碳净排放量曲线都呈"倒U"型,在2035年达到高峰,高峰值分别为和129.71 MtC和118.89 MtC;在森林碳汇中,原有森林的碳汇作用在现在和未来一段时间内处于主导地位,但新造林有着巨大的碳汇潜力,所以在保护原有森林的同时要植树造林,从生态学角度抵消碳排放;森林碳汇只能减少小部分碳排放,更主要的是改善云南省的能源结构,加快技术进步速度,开发水电等新能源,从根本上减少温室气体的排放。  相似文献   

8.
While many factors affecting human health that will alter with climate change are being discussed, there has been no discussion about how a warmer future will affect man’s thermoregulation. Using historical climate data for an Australian city and projections for Australia’s climate in 2070, we address the issue using heat balance modelling for humans engaged in various levels of activity from rest to manual labour. We first validate two heat balance models against empirical data and then use the models to predict the number of days at present and in 2070 that (1) sweating will be required to attain heat balance, (2) heat balance will not be possible and hyperthermia will develop, and (3) body temperature will increase by 2.5°C in less than 2 h, which we term “dangerous days”. The modelling is applied to people in an unacclimatised and an acclimatised state. The modelling shows that, for unacclimatised people, outdoor activity will not be possible on 33–45 days per year, compared to 4–6 days per year at present. For acclimatised people the situation is less dire but leisure activity like golf will be not be possible on 5–14 days per year compared to 1 day in 5 years at present, and manual labour will be dangerous to perform on 15–26 days per year compared to 1 day per year at present. It is obvious that climate change will have important consequences for leisure, economic activity, and health in Australia.  相似文献   

9.
An indoor mesocosm system was set up to study the response of phytoplankton and zooplankton spring succession to winter and spring warming of sea surface temperatures. The experimental temperature regimes consisted of the decadal average of the Kiel Bight, Baltic Sea, and three elevated regimes with 2°C, 4°C, and 6°C temperature difference from that at baseline. While the peak of the phytoplankton spring bloom was accelerated only weakly by increasing temperatures (1.4 days per degree Celsius), the subsequent biomass minimum of phytoplankton was accelerated more strongly (4.25 days per degree Celsius). Phytoplankton size structure showed a pronounced response to warming, with large phytoplankton being more dominant in the cooler mesocosms. The first seasonal ciliate peak was accelerated by 2.1 days per degree Celsius and the second one by 2.0 days per degree Celsius. The over-wintering copepod populations declined faster in the warmer mesocosm, and the appearance of nauplii was strongly accelerated by temperature (9.2 days per degree Celsius). The strong difference between the acceleration of the phytoplankton peak and the acceleration of the nauplii could be one of the “Achilles heels” of pelagic systems subject to climate change, because nauplii are the most starvation-sensitive life cycle stage of copepods and the most important food item of first-feeding fish larvae. Priority programme of the German Research Foundation—contribution 3.  相似文献   

10.
海洋浮游古菌MGⅡ是海洋表层水体中最丰富的古菌类群。自1992年被发现以来,如今依然没有被成功分离纯化。前人基于16S rRNA基因的研究认为MGⅡ可以被分为MGⅡa、MGⅡb和MGⅡc三个亚类。近年来,对大量的宏基因组测序数据的分析表明,MGⅡ在分类学上属于广古菌门热源体纲下的一个目,包含MGⅡa和MGⅡb两个科。以前通过16S rRNA基因高通量测序结果得出的少量MGⅡc,在宏基因组测序的数据中并没有找到,因此最近两年的研究认为MGⅡ主要由MGⅡa和MGⅡb组成。本文综述了海洋浮游古菌MGⅡ的丰度和多样性分布特征、潜在的生态功能、生态关系以及培养等方面的研究进展,比较了MGⅡa和MGⅡb的异同点,并对当前的研究热点和趋势进行了讨论和展望。  相似文献   

11.

Purpose  

Climate change impacts in life cycle assessment (LCA) are usually assessed as the emissions of greenhouse gases expressed with the global warming potential (GWP). However, changes in surface albedo caused by land use change can also contribute to change the Earth’s energy budget. In this paper we present a methodology for including in LCA the climatic impacts of land surface albedo changes, measured as CO2-eq. emissions or emission offsets.  相似文献   

12.
Understanding the historical biogeography of this global biodiversity hotspot is as important to long-term conservation goals as ecology and evolution are to understanding current patterns and processes. Today’s geography is, however, misleading and typical of only ~2% of the last million years; >90% of that time the region’s land area was 1.5–2.0 times larger as mean sea levels were 62 m below today’s, climates were cooler, and extensive forests and savanna covered the emerged Sunda plains. The region’s land area varied two-fold as sea levels fluctuated up to ±50 m with each of ~50 Pleistocene glacial cycles, and forests expanded and contracted with oscillations in land area and seasonality. This dynamic geographic history is relevant to the development of biogeographic regionalism and shows that it is today’s forests that are refugial, not those of the Last Glacial Maximum. This history affects how species will adapt or shift their ranges in response to global warming and further decreases in land area (submergence of low-lying coastal areas) during the 21st century. The alternative is mass species extinction. The biota is also threatened by the continued destruction of forest, destruction of Mekong River flood-pulse based ecosystems, and continued human population growth. Human biogeography will become more important in conservation planning as tens of millions of people who depend on protected area forests, riverine ecosystems, and coastal habitats become environmental refugees. Conservation scientists need to become more involved in regional ecological education, environmental stewardship, and ecosystem-based adaptation to sustain as much as possible of this rich biota and the ecological services it provides.  相似文献   

13.
In Population Genetics, two populations are distinguished from each other on the basis of the differences in the distributions of the alleles at the locus or loci under consideration. These differences are measured by a “genetic distance” between the two populations (not to be confused with genetic distance between two loci, which is based on recombination fractions) and they play a major role in inferences at the population level. Several measures of genetic distance have been proposed by different authors (Sanghvi 1953; Cavalli-Sforza and Edwards 1967; Jukes and Cantor 1969; Nei 1972; Kimura 1980; Reynoldset al 1983; reviews in Felsenstein 1991; Nei and Kumar 2000). Most of these measures are actually dissimilarity measures and not mathematically true distance measures (B-Rao and Majumdar 1999). Independently, and much before the geneticists, statisticians too were concerned with the idea of distinguishing between two (statistical) populations. In order to discriminate between two populations on the basis of one or more characters, divergence measures like “Mahalanobis’D 2 statistic” or “Mahalanobis’ generalized distance” (1936) and “Bhattacharyya’s distance” (1943, 1946), Kullback-Leibler’s divergence measure (1951) etc. have been proposed by statisticians. Mukherjee and Chattopadhyaya (1986) have mentioned measures based on distances, association between two attributes and discrimination function. There are similarities between the distance measures defined by applied scientists and by theoreticians. Felsenstein (1985) shows that three of the allele frequency-based genetic distance measures were anticipated by Bhattacharyya (1946). Nei and Takezaki (1994) have also studied the effectiveness of several genetic distance measures in the context of phylogenetic analysis, including Bhattacharyya’s distance measure.  相似文献   

14.
Contribution of “Women’s Gold” to West African Livelihoods: The Case of Shea ( Vitellaria paradoxa ) in Burkina Faso. This paper (i) quantifies the contribution that Vitellaria paradoxa makes to the total income of rural households belonging to different economic groups in two areas of Burkina Faso; (ii) quantifies the involvement of women in shea nuts and fruits collection and processing; and (iii) empirically verifies the “gap filling” function of shea products in Burkina Faso by quantifying the commercialization and subsistence use of shea fruits, nuts, and butter between agricultural seasons. Based on data collected from structured household surveys used on a quarterly basis during a one-year period on 536 households, we demonstrate that the reliance on shea is generally high in the sampled populations, and is at its highest for the poorest households, for which it contributes 12 % of total household income. Moreover, shea nut collection and processing was found to provide a valuable source of cash income to female household members who otherwise have very few income possibilities. Finally, due to its ecology, shea fills in an income gap during a period where human activities are at their highest while income is at its lowest. Although shea is crucial for poor people’s livelihoods and for the generation of income for women, its harvesting and processing are time-consuming activities that generate low returns per unit of labor. We argue that shea collection and processing should therefore not be considered as a remedy to poverty but instead as a way for households to diversify their livelihood strategy and decrease their vulnerability to food insecurity and climate variability.  相似文献   

15.
This paper utilizes Iris Marion Young’s critical, post-9/11 reading of Thomas Hobbes, “as a theorist of authoritarian government grounded in fear of threat” (Young 2003). Applying Young’s reading of Hobbes to the high-profile ethicist Julian Savulescu’s advocacy of genetic enhancement reveals an underlying unjust discrimination in Savulescu’s use of patriarchal protector–protected analogies between family and state. First, the paper shows how Savulescu’s concept of procreative beneficence, in which parents use genetic selection to have children who will have the “best lives” possible, is unjustly discriminatory against marginalized groups. Increasingly, however, he has invoked public security to justify genetic interventions. In recent speeches, Savulescu has argued a global state of emergency is developing due to a combination of the global environmental crisis, the threat of bioterrorism, and the failure of liberalism. To help deal with this emerging state of emergency, Savulescu advocates an unjustly discriminatory array of genetic-based governance practices, including detention and segregation.  相似文献   

16.
A four-site haplotype system at the dopamine D2 receptor locus (DRD2) has been studied in a global sample of 28 distinct populations. The haplotype system spans about 25 kb, encompassing the coding region of the gene. The four individual markers include three TaqI restriction site polymorphisms (RSPs) – TaqI “A”, “B”, and “D” sites – and one dinucleotide short tandem repeat polymorphism (STRP). All four of the marker systems are polymorphic in all regions of the world and in most individual populations. The haplotype system shows the highest average heterozygosity in Africa, a slightly lower average heterozygosity in Europe, and the lowest average heterozygosities in East Asia and the Americas. Across all populations, 20 of the 48 possible haplotypes reached a frequency of at least 5% in at least one population sample. However, no single population had more than six haplotypes reaching that frequency. In general, African populations had more haplotypes present in each population and more haplotypes occurring at a frequency of at least 5% in that population. Permutation tests for significance of overall disequilibrium (all sites considered simultaneously) were highly significant (P<0.001) in all 28 populations. Except for three African samples, the pairwise disequilibrium between the outermost RSP markers, TaqI “B” and “A”, was highly significant with D’ values greater than 0.8; in two of those exceptions the RSP marker was not polymorphic. Except for those same two African populations, the 16-repeat allele at the STRP also showed highly significant disequilibrium with the TaqI “B” site in all populations, with D’ values usually greater than 0.7. Only four haplotypes account for more than 70% of all chromosomes in virtually all non-African populations, and two of those haplotypes account for more than 70% of all chromosomes in most East Asian and Amerindian populations. A new measure of the amount of overall disequilibrium shows least disequilibrium in African populations, somewhat more in European populations, and the greatest amount in East Asian and Amerindian populations. This pattern seems best explained by random genetic drift with low levels of recombination, a low mutation rate at the STRP, and essentially no recurrent mutation at the RSP sites, all in conjunction with an “Out of Africa” model for recent human evolution. Received: 14 January 1998 / Accepted 19 March 1998  相似文献   

17.
Maynard et al. (Coral Reefs 27:745–749, 2008a) claim that much of the concern about the impacts of climate change on coral reefs has been “based on essentially untested assumptions regarding reefs and their capacity to cope with future climate change”. If correct, this claim has important implications for whether or not climate change represents the largest long-term threat to the sustainability of coral reefs, especially given their ad hominem argument that many coral reef scientists are guilty of “popularising worst-case scenarios” at the expense of truth. This article looks critically at the claims made by Maynard et al. (Coral Reefs 27:745–749, 2008a) and comes to a very different conclusion, with the thrust and veracity of their argument being called into question. Contrary to the fears of Grigg (Coral Reefs 11:183–186, 1992), who originally made reference to the Cassandra syndrome due to his concern about the sensationalisation of science, the proposition that coral reefs face enormous challenges from climate change and ocean acidification has and is being established through “careful experimentation, long-term monitoring and objective interpretation”. While this is reassuring, coral reef ecosystems continue to face major challenges from ocean warming and acidification. Given this, it is an imperative that scientists continue to maintain the rigour of their research and to communicate their conclusions as widely and clearly as possible. Given the shortage of time and the magnitude of the problem, there is little time to spare.  相似文献   

18.
We summarize the ethnographic literature illustrating that “abnormal birth” circumstances and “ill omens” operate as cues to terminate parental investment. A review of the medical literature provides evidence to support our assertion that ill omens serve as markers of biological conditions that will threaten the survival of infants. Daly and Wilson (1984) tested the prediction that children of demonstrably poor phenotypic quality will be common victims of infanticide. We take this hypothesis one stage further and argue that some children will be poor vehicles for parental investment yet are not of demonstrably poor quality at birth. We conclude that when people dispose of infants due to “superstitious beliefs” they are pursuing an adaptive strategy in eliminating infants who are poor vehicles for parental investment. Catherine Hill lectures in biological anthropology/human sciences at Durham University’s University College, Stockton. She trained in biological anthropology at University College, London. Her current research interests include human and nonhuman primate socioecology and human resource ecology and development issues. Helen Ball lectures in biological anthropology/human sciences at Durham University’s University College, Stockton. She trained in biological anthropology at the University of Massachusetts at Amherst. Her current research interests include nonhuman primate behavior and socioecology, reproductive biology, and evolutionary issues.  相似文献   

19.
Accurate estimates of global carbon emissions are critical for understanding global warming. This paper estimates net carbon emissions from land use change in Bolivia during the periods 1990–2000 and 2000–2010 using a model that takes into account deforestation, forest degradation, forest regrowth, gradual carbon decomposition and accumulation, as well as heterogeneity in both above ground and below ground carbon contents at the 10 by 10 km grid level. The approach permits detailed maps of net emissions by region and type of land cover. We estimate that net CO2 emissions from land use change in Bolivia increased from about 65 million tons per year during 1990–2000 to about 93 million tons per year during 2000–2010, while CO2 emissions per capita and per unit of GDP have remained fairly stable over the sample period. If we allow for estimated biomass increases in mature forests, net CO2 emissions drop to close to zero. Finally, we find these results are robust to alternative methods of calculating emissions.  相似文献   

20.
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