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51.
Water security: Old concepts,new package,what value?   总被引:1,自引:0,他引:1  
“Water security” has come to infiltrate prominent discourse in the international water and development community, and achieving it is often viewed as a new water sector target. Despite the elevated status that the concept has increasingly acquired, understandings of the term are murky and quantification is rare. To promote a more tangible understanding of the concept, this paper develops an index for evaluating water security at a country level. The index is comprised of indicators in five components considered to be critical to the concept: (i) basic needs; (ii) agricultural production; (iii) the environment; (iv) risk management; and (v) independence. Achieving water security in these components can be considered necessary but insufficient criteria to measure the achievement of security in related areas such as health, livelihoods, and industry. After populating indicators with data from Asia‐Pacific countries, results are interpreted and the viability of methods is discussed. This effort comprises an important first step for quantifying and assessing water security across countries, which should spur more concrete understanding of the term and discussion of its added value.  相似文献   
52.
Fujii Y  Yan J  Harada KH  Hitomi T  Yang H  Wang P  Koizumi A 《Chemosphere》2012,86(3):315-321
In this study, 90 human breast milk samples collected from Japan, Korea, and China were analyzed for perfluorooctanoic acid (PFOA) (C8), perfluorononanoic acid (PFNA) (C9), perfluorodecanoic acid (PFDA) (C10), perfluoroundecanoic acid (PFUnDA) (C11), perfluorododecanoic acid (PFDoDA) (C12), and perfluorotridecanoic acid (PFTrDA) (C13). In addition, infant formulas (n = 9) obtained from retail stores in China and Japan were analyzed. PFOA was the predominant compound and was detected in more than 60% of samples in all three countries. The PFOA, PFNA, PFDA, and PFUnDA levels in Japan were significantly higher than those in Korea and China (p < 0.05). The PFTrDA level was highest in Korea (p < 0.05). The median PFOA concentrations were 89 pg mL−1 (48% of total perfluorinated carboxylic acids (PFCAs) (C8-C13)) in Japan, 62 pg mL−1 (54%) in Korea, and 51 pg mL−1 (61%) in China. The remaining ∑PFCAs (C9-C13) were 95 pg mL−1 in Japan, 52 pg mL−1 in Korea, and 33 pg mL−1 in China. Among the long-chain PFCAs, odd-numbered PFCAs were more frequently detected than even-numbered PFCAs, except for PFDA in Japan. There were no evident correlations between the mother’s demographic factors and the PFCA concentrations. PFOA, PFNA, and PFDA were frequently detected in both Japan and China, but there were no significant differences between the two countries. The total PFCA concentrations in the infant formulas were lower than those in the breast milk samples in Japan (p < 0.05), but not in China (p > 0.05). In conclusion, various PFCAs were detected in human breast milk samples from East Asian countries.  相似文献   
53.
目的分析东亚地区气溶胶的垂直分布特征。方法利用2006—2012年CALIPSO星载激光雷达资料,基于气溶胶光学厚度分析结果,选取有代表性的经度带和纬度带,分别研究东亚大陆东部沿海地区气溶胶的垂直分布和东亚-北太平洋地区沙尘气溶胶的垂直分布。在此基础上,选取三个有代表性的格点,进一步研究华北和华南地区气溶胶的垂直分布及塔克拉玛干沙漠沙尘的气溶胶垂直分布,并对其垂直分布特征曲线进行拟合。结果平均来看,除少数地区个别月份外,东亚地区气溶胶主要出现在近地面附近。东部沿海地区,一定高度以上,气溶胶的消光系数随高度的增加总体上呈指数减小;西北沙尘源区,大致在近地面至对流层中层,沙尘气溶胶的消光系数随高度的增加几乎呈线性递减。气溶胶的垂直分布具有显著的月际变化和地区差异,中纬度地区,亚洲沙尘气溶胶跨北太平洋传输在1—5月份较强。结论高垂直分辨率的CALIPSO资料可作为精细分析气溶胶垂直分布特征的有力工具。  相似文献   
54.
We developed an age-structured population model of splitnose rockfish, Sebastes diploproa, in the Northeast Pacific Ocean. Splitnose rockfish is a bycatch species that co-occurs with several commercially important species that are currently declared overfished. Bycatch species are typically not the focus of stock assessment efforts because of their limited economic importance, but they may suffer the same population declines as species with which they co-occur. To examine the dynamics of splitnose rockfish for the first time, we analyzed data from three groundfish fisheries and four research surveys conducted in the Northeast Pacific Ocean. To develop a model, we used Stock Synthesis, a statistical framework for the construction of a population dynamics models utilizing both fishery-dependent and fishery-independent data. In the model, we reconstructed the total catch of the species back to 1900, estimated the dynamics of the stock spawning output and recruitment and evaluated biomass depletion relative to the stock's unfished state, as well as sources of uncertainty in model outputs. The results indicate that the splitnose rockfish is currently not overfished even though it has experienced several periods of abrupt decline in its biomass. Revisiting age data from earlier years, monitoring fishery discard, and investigating the spatial dynamics of splitnose rockfish is important to further improve the understanding of this species’ population dynamics, and decrease uncertainty in model results.  相似文献   
55.
Only a few rigorous studies have attempted to focus on the topic of plant indicators in relation to natural disasters, although recently an increasing number of people have realized its significance. In an effort to aid disaster management, this article studied and aimed to improve the status of plant indicators in predicting or signaling natural disasters. Using a qualitative content analysis, the plant indicators’ uncertain status and certain status are systematically compared using specific plants, developed community efforts, indigenous community traditions, and characteristics of natural disaster management. A key tenet is that all stakeholders must change plant indicators’ uncertain status to certain status by comprehensively elaborating on the integration between developed communities and indigenous communities, plant indicators as a research agenda, the inclusion of plant indicators in disaster management policy and local plans, and education and training.  相似文献   
56.
目的 掌握东南亚地区环境特征,提出产品环境适应性工作对策。方法 采用主成分分析法开展东南亚地区环境精细化分类,依据分类结果,开展环境特征分析和规律研究,并在产品环境适应性问题原因分析的基础上,提出东南亚地区使用产品环境适应性工作对策。结果 东南亚地区具有年温度较高、相对湿度高、雨量充沛、太阳辐射较强等特征,但不同类别之间具有一定的差异性,D1、D2类环境呈现一定的季节性特征,D3、D4类全年环境较为稳定,温度、平均湿度、太阳辐射和降雨量均稳定地保持在较高量值范围内,温度常年保持在20~30 ℃,平均相对湿度在70%以上。结论 东南亚地区环境整体较为严酷,在产品环境适应性论证、设计和使用维护等阶段应采取针对性措施,以保证东南亚地区使用产品的环境适应性。  相似文献   
57.
中亚地区粮食生产潜力及发展潜力分析——基于GAEZ方法   总被引:1,自引:0,他引:1  
中亚地区因特殊的地理位置和高粮食生产能力,对维护世界粮食安全意义重大,发掘中亚地区粮食生产潜力有助于全球粮食危机缓解。采用GAEZ方法,结合联合国粮农组织数据库,定量分析了中亚地区5个国家、9种粮食作物的潜在单产及潜在面积,并通过控制粮食单产和生产面积的变化提出三种假设,测算出不同假设下中亚地区的粮食生产潜力、发展潜力和发展潜力幅度。结果表明:中亚地区的哈萨克斯坦粮食生产潜力和发展潜力大;小麦、大麦产量有较大提升空间,高粱、黑麦、谷子、燕麦、荞麦产量提升空间小且潜力集中在哈萨克斯坦,但高粱的发展潜力幅度很大。  相似文献   
58.
资源型城市经济转型仍然是当前我国城市发展的重大问题。基于资源型城市经济转型核心内涵,采用平衡计分卡和关键绩效指标思想方法,概括出资源型城市经济转型的绩效特征,进而构建包括“资源依赖、经济水平、生态效率、社会福利、创新驱动”五方面关键特征的五维评价法,选择能够准确反映经济转型关键过程和结果的少数关键参数作为评价指标,运用脱钩分析、超效率数据包络分析、回归分析、耦合度模型、熵权法、典型相关分析等计量模型,使绩效评价结果与经济转型真实机制相一致。以东北地区7个典型煤炭城市作为案例,运用五维评价法对这些城市2003年以来的经济转型进行绩效评价。结果发现:从转型效果看,7个城市都初步实现了经济增长驱动力的转换,其中辽源的第二产业发展绩效较好,辽源和阜新的产业演替绩效较好;从转型质量看,生态效率均显著提升,其中辽源、阜新、双鸭山提升了经济相对发展水平,实证检验表明7个城市的经济转型中,改善经济对社会福利的支持力不够;从最终目标实现程度看,7个城市的科技和创新水平都严重不足,经济增长趋缓,都未能实现经济转型最终目标。  相似文献   
59.
Agriculturally altered vegetation, especially oil‐palm plantations, is rapidly increasing in Southeast Asia. Low species diversity is associated with this commodity, but data on anuran diversity in oil‐palm plantations are lacking. We investigated how anuran biological diversity differs between forest and oil‐palm plantation, and whether observed differences in biological diversity of these areas is linked to specific environmental factors. We hypothesized that biological diversity is lower in plantations and that plantations support a larger proportion of disturbance‐tolerant species than forest. We compared species richness, abundance, and community composition between plantation and forest areas and between site types within plantation and forest (forest stream vs. plantation stream, forest riparian vs. plantation riparian, forest terrestrial vs. plantation terrestrial). Not all measures of biological diversity differed between oil‐palm plantations and secondary forest sites. Anuran community composition, however, differed greatly between forest and plantation, and communities of anurans in plantations contained species that prosper in disturbed areas. Although plantations supported large numbers of breeding anurans, we concluded the community consisted of common species that were of little conservation concern (commonly found species include Fejervarya limnocharis, Microhyla heymonsi, and Hylarana erythrea). We believe that with a number of management interventions, oil‐palm plantations can provide habitat for species that dwell in secondary forests. Efectos de las Plantaciones de Palma de Aceite sobre la Diversidad de Anuros Tropicales Faruk et al.  相似文献   
60.
Abstract:  With about half the world's human population and booming economies, Asia faces numerous challenges to its biodiversity. The Asia Section of the Society for Conservation Biology has identified some key policy issues in which significant progress can be made. These include developing new sources of funding for forest conservation; identifying potential impacts of energy alternatives on the conservation of biodiversity; curbing the trade in endangered species of plants and animals; a special focus on the conservation of mountain biodiversity; enhancing relevant research; ensuring that conservation biology contributes to major international conventions and funding mechanisms; using conservation biology to build a better understanding of zoonotic diseases; more effectively addressing human–animal conflicts; enhancing community-based conservation; and using conservation biology to help address the pervasive water-deficit problems in much of Asia. These challenges can be met through improved regional cooperation among the relevant stakeholders .  相似文献   
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