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361.
Water resource structure is one of the most important factors that constrain the economic development in arid–semiarid areas. Sustainable use of water requires a thorough understanding of the local geology and hydrology and developing of effective protection strategies. Discussed in this paper is a study on the phreatic water quality of the Yuxi River Valley of Shaanxi Province, China. The Yuxi River Valley passes through the Shaanbei energy base, which demands large quantities of high-quality water. A total of 129 water samples were collected in 4,938 km2 in a recent study to delineate the areas with water suitable for drinking, industrial, and agricultural usage and areas with poor quality. The study indicates that the poor quality of water contains high concentrations of NH4+ and NO2−1, indicating possible contamination by waste disposal in the nearby cities and towns. A series of strategies are proposed to protect the water in the Yuxi River Valley, including proper treatment and recycling of the waste water in the cities and towns, strict control of the waste-water discharge from any new factories and mines, and prevention of groundwater contamination by wastes containing heavy metals.  相似文献   
362.
Water is a major limiting factor in desert ecosystems. In order to learn how plants cope with changes in water resources over time and space, it is important to understand plant–water relations in desert region. Using the oxygen isotopic tracing method, our study clarified the seasonal changes in the water use strategies of three co‐occurring desert shrubs. During the 2012 growing season, δ18O values were measured for xylem sap, the soil water in different soil layers between 0 and 300 cm depth and groundwater. Based on the similarities in δ18O values for the soil water in each layer, three potential water sources were identified: shallow soil water, middle soil water and deep soil water. Then we calculated the percentage utilization of potential water sources by each species in each season using the linear mixing model. The results showed that the δ18O values of the three species showed a clear seasonal pattern. Reaumuria songarica used shallow soil water when shallow layer was relatively wet in spring, but mostly took up middle soil water in summer and autumn. Nitraria tangutorum mainly utilized shallow and middle soil water in spring, but mostly absorbed deep soil water in summer and autumn. Tamarix ramosissima utilized the three water sources evenly in spring and primarily relied on deep soil water in summer and autumn. R. songarica and N. tangutorum responded quickly to large rainfall pulses during droughts. Differential root systems of the three species resulted in different seasonal water use strategies when the three competed for water. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
363.
The lack of ambitious climate change policies in large anglophone countries, such as the United States, has been explained by the strong media presence of denialist arguments against climate science. Such counterarguments are less visible in the news media of most European countries. Why do many of these countries nevertheless fail to enact ambitious climate change policies? This paper suggests that influential organizations may block ambitious climate change policies in corporatist countries without an extensive media strategy or a strong denialist message. We draw from theories on the policy process, policy networks, influence strategies, and comparative politics to formulate hypotheses about the existence, influence, and strategies of organizations that oppose ambitious climate policy. We test these hypotheses using an original combination of media data and survey data on the national climate policy network in Finland, a corporatist European country that has long lacked ambitious climate policies. The findings show that a coalition that prioritizes economic competitiveness over climate change mitigation is influential and occupies a central position in the policy network. This pro-economy lobby does not question the validity of climate science or actively seek media visibility. Rather, it influences the policy process using other strategies, such as inside lobbying, and appears in the news media less often than other climate policy organizations. Our results suggest that opponents of climate change mitigation can be powerful despite a weak media presence. This implies that studies on climate politics should pay more attention to strategies of influencing beyond the media spotlight.  相似文献   
364.
Water problems due to scarcity, inaccessibility, or poor quality are a major barrier to household functioning, livelihood, and health globally. Household-to-household water borrowing has been posited as a strategy to alleviate unmet water needs. However, the prevalence and predictors of this practice have not been systematically examined. Therefore, we tested whether water borrowing occurs across diverse global contexts with varying water problems. Second, we tested if household water borrowing is associated with unmet water needs, perceived socio-economic status (SES), and/or water-related system failures, and if water access moderated (or changed) these relationships. Using survey data from the Household Water Insecurity Experiences (HWISE) study from 21 sites in 19 low- and middle-income countries (n = 5495 households), we found that household-to-household water borrowing was practiced in all 21 sites, with 44.7% (11.4–85.4%) of households borrowing water at least once the previous month. Multilevel mixed-effect logistic regression models demonstrate that high unmet water needs (odds ratio [OR] = 2.86], 95% confidence interval [CI] = 2.09–3.91), low perceived SES (OR = 1.09; 95% CI = 1.05–1.13), and water-related system failures (23–258%) were all significantly associated with higher odds of water borrowing. Significant interactions (all p < 0.01) between water access, unmet water needs, and water-related system failures on water borrowing indicate that water access moderates these relationships. These data are the first to demonstrate that borrowing water is commonly used by households around the world to cope with water insecurity. Due to how prevalent water borrowing is, its implications for social dynamics, resource allocation, and health and well-being are likely vast but severely under-recognized.  相似文献   
365.
研究国际性珠宝首饰展览会的会展营销策略对我国珠宝首饰展览会的提高与发展具有重要意义。通过实地考察和资料收集,运用营销学的知识总结了国际性珠宝首饰展览会的会展营销要素,并结合会展学的知识从规划展区、招揽客户、开展公关活动和管理客户关系等方面分析了其会展营销策略,旨在为国内珠宝首饰展览组织机构更好地举办珠宝首饰展览会提供一些参考。  相似文献   
366.
boncati0uofDcsendcahoninchhaboenificationisoneofthem0stseriotisenvirorunedlissuesoneafth.TheInteInaonalConedontoC0mbatbeeftifiCationswtinforberl994addressed[4]thadeSenificationislandhardation,resultingfromvariousfaders,indudingdiInaticvariationsandhuInana…  相似文献   
367.
Recent legislation for the restitution of ownership rights to, and subsequent management of, formerly privately owned forests in postsocialist Bulgaria has focused largely albeit not exclusively on the restored forests from the perspective of timber production, that is, `forest' equals `harvestable timber resource'. Using ethnographic data collected in rural Rhodope Mountain communities, this paper presents a local-level perspective on forests and forest use, including the meaning that forests hold for local residents as a source of non-timber forest products such as mushrooms and medicinal plants, of animal pasture, and of firewood for household heating and cooking. This local social perspective is then contrasted with the timber-resource focus of the forestry legislation and subsequent planning for forest use. The scale of forest ownership – in part a function of the restitution legislation – is also addressed in relation to the practicalities of resource management. Generally, the paper demonstrates a mismatch between the postsocialist forestry legislation and local practice and conditions with regard to forests and the natural resources therein. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
368.
Shlomo Hasson 《GeoJournal》2001,53(3):311-322
Jerusalem is a city of many contrasts. It is a historical-symbolic city, revered by Muslims, Christians and Jews. However, its citizens segregate ethno-nationally, culturally and socially, into different identity groups: Jews and Arabs, Haredi (`ultra-Orthodox') and secular Jews, and lower and upper class socio-economic groups. This essay focuses on how political and social struggles over territories reshape the nature of the identities of four distinct groups in Jerusalem. These are ethno-national groups (Israeli Jews and Palestinian Arabs), cultural groups (ultra-Orthodox Jews, in Hebrew Haredim (zealots), and non-Orthodox Jews), ethno-social groups (disadvantaged groups mainly of oriental descent, in Hebrew Mizrahim and advantaged groups) and economic and ecological groups (the business sector and inhabitants of private residential areas of the city). Thus, long-term historical processes have produced distinct ethno-national, cultural and social identity groups, which occupy specific territories within Jerusalem. The different groups have endowed their territory with dissimilar geopolitical, cultural, and economic meanings and played a major role in the reconstruction of national, cultural, social and ecological identities in the city. The city of Jerusalem is not only a spiritual centre associated with age-long dreams for peace and justice, it is also a violent city, rife with tensions and conflicts, a symbol of national, cultural, economic and ecological struggles. Perhaps the greatest challenge facing all those concerned about its future is whether Jerusalem's universal image of a spiritual, tolerant and just city can overcome its current, particularistic and conflict ridden image.  相似文献   
369.
为应对国际环境的复杂性和不确定性,生计恢复力研究成为群体或个人应对外界干扰、减少贫困和提高适应能力的有效方法。通过梳理国内外相关研究成果,总结了生计恢复力的概念、分析框架与评价方法研究进展,揭示了其对推动生计恢复力创新研究的重要启示。研究发现:国内外学者在生计恢复力的概念上已达成初步共识,但生计恢复力分析框架缺乏普适性,研究方法和技术缺乏深度融合,研究对象的范围有待拓展。今后应加强生计恢复力理论方法研究,构建国内生计恢复力研究的一般范式;开展空间技术应用与个体福祉研究,拓宽生计恢复力评价内容和方法;加强分析多重干扰下生计恢复力动态演化机制,深化生计恢复力适应性管理综合研究,非农个体生计恢复力(尤其是旅游生计恢复力)的研究是拓宽生计恢复力理论研究和服务全球可持续发展需求的重点领域。  相似文献   
370.
杨振山  王玉璇 《地理研究》2018,37(11):2153-2164
开发区在中国城市与区域发展中作为经济活动和流动人口的聚集区域发挥着重要作用。基于对南沙新区流动人口的问卷调查与访谈,从生计空间的角度测量流动人口的生计资本,分析其生计空间特征,并与当地居民进行比较。研究发现,流动人口在开发区的生计空间存在延伸或压缩。其中,经济空间得到了延伸,制度空间、社交空间、公共服务空间、居住空间等存在不同程度的压缩。经济空间的扩张是吸引流动人口在开发区就业的主要因素,但其余空间的压缩和经济空间的有限延伸使流动人口在进入后缓慢外迁。因此,改善开发区流动人口的生计空间,对于提升城市工业工人的生活条件,制定城市一体化发展战略,促进城市社会空间整体提升具有重要意义。  相似文献   
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