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71.
Access to water for domestic and irrigation uses remains limited across Sub-Saharan Africa, particularly in rural areas. While the technical feasibility of implementing innovative technologies to improve water supply has been often evaluated, less is known about the drivers that motivate users to pay for obtaining the inherent benefits of improved water supply. In this article, the determinants of the marginal willingness to pay (mWTP) for improved domestic and irrigation water are investigated. For this purpose, a contingent valuation study is performed in rural Rwanda. This study uses survey data from 316 households situated in 8 villages, in which ~20% of the households receive electricity thanks to microgrids powered by solar energy. It is found that the mWTP for improved domestic water supply is influenced by the proportion of children in the household, business ownership, and satisfaction with water quantity and quality. The mWTP for irrigation is determined by respondent education, business ownership and crop area planted. This paper contributes to the literature by allowing a comparison of the determinants of the mWTP for improved domestic water supply to the determinants of the mWTP for irrigation. Another contribution is to examine the mWTP for improved water infrastructure in partially electrified villages. Identifying areas with high marginal benefits from water can guide infrastructure investment and electrification efforts while improving well-being and increasing revenues in rural areas.  相似文献   
72.
Testing Hypotheses for the Success of Different Conservation Strategies   总被引:4,自引:0,他引:4  
Abstract:  Evaluations of the success of different conservation strategies are still in their infancy. We used four different measures of project outcomes—ecological, economic, attitudinal, and behavioral—to test hypotheses derived from the assumptions that underlie contemporary conservation solutions. Our hypotheses concerned the effects of natural resource utilization, market integration, decentralization, and community homogeneity on project success. We reviewed the conservation and development literature and used a specific protocol to extract and code the information in a sample of papers. Although our results are by no means conclusive and suffer from the paucity of high-quality data and independent monitoring (80% of the original sample of 124 projects provided inadequate information for use in this study), they show that permitted use of natural resources, market access, and greater community involvement in the conservation project are all important factors for a successful outcome. Without better monitoring schemes in place, it is still impossible to provide a systematic evaluation of how different strategies are best suited to different conservation challenges.  相似文献   
73.
Kazakhstan is an upper-middle-income country and one of the coldest countries in the world with rich energy resources and energy prices considerably lower than in developed countries. This paper presents the first comprehensive overview of household fuel use in Kazakhstan and assesses the causes and extent of energy poverty using the Households Living Conditions Survey dataset of 12,000 households. The results show that there is an overwhelming reliance on coal in Kazakhstan: 40% of all surveyed households use coal for heating, cooking and other needs. In general, liquefied petroleum gas is mainly used for cooking, coal and firewood for heating, while electricity is rarely used for heating. Energy poverty was less prevalent in oil and gas rich regions, due to low gas prices and higher income levels in those regions, while households located in the North Kazakhstan, Central and East Kazakhstan mainly suffer from lack of cleaner fuel options, income poverty, longer and colder winters and consequently energy affordability. Despite low energy prices in Kazakhstan, the results demonstrate that 28% of surveyed households spend more than 10% of their income on energy. Gas and district heating infrastructure coverage and income inequality across its regions contributed the most to energy poverty in Kazakhstan. Energy prices are regulated and indirectly subsidised. Removing energy subsidies alone may worsen energy affordability of households. Offering direct subsidies to cover part of the energy expenditures may not fully solve the problem, but subsidies, interventions for efficient technologies and fuels, dwelling energy-efficiency improvements are necessary.  相似文献   
74.
关于生物剽窃规制框架的法律思考   总被引:2,自引:0,他引:2  
生物剽窃是指生物遗传资源勘探者未经提供者同意并给予合理补偿,就商业化地利用后者的生物遗产资源,又借助知识产权独占惠益的行为。生物剽窃严重损害作为资源提供方的发展中国家的利益,违反自然资源国家主权原则,《生物多样性公约》及其议定书形成一系列规制措施。我国应借鉴国际立法经验,并结合本国国情,建立健全诸如遗传资源数据库、事先知情同意、共同协商、对价补偿和惠益分享及所得撤销等遗传资源保护法律制度。  相似文献   
75.
Surprisingly little attention is paid to the role of digital technology and related forms of data production, storage, processing, and sharing in humanitarian governance. This paper uses Michael Barnett's ( 2013 ) conceptualisation of humanitarian governance when arguing for a better accounting of technology in literature on humanitarian governance. Specifically, it proposes a two‐fold alertness to governance of (a) the uses of new technology and (b) that which is produced by digital technologies. This elucidates important issues, including that of access to digitalised data collected from humanitarian subjects, with implications for their (in)security. The paper concludes by suggesting that access is no longer ‘only’ about challenges of gaining access to vulnerable populations, but also about challenges of preventing access to vulnerable digital bodies and their use for aggressive purposes. In short, access and protection acquire a new dimension and analyses of humanitarian governance must be more attentive to the role of digital technology.  相似文献   
76.
ABSTRACT

Climate change and a rapidly growing human population have put ever greater strains on the global food system. Although the number of food insecure people in the world has reached a record low, changing land use and climate variability will threaten our ability to maintain this progress. Profound changes in the structure of economies around the world have affected agricultural production and how food is delivered to the consumer. This paper explores connections between land use, environmental change and food availability, access, and utilization. Each of these elements of food security has vulnerabilities to changing environmental conditions and land use that can be explored using satellite remote sensing observations. Technology is a key way environmental changes can be quantified and used in food security assessment.  相似文献   
77.
《中华人民共和国环境影响评价法》实施二十年以来,生态环境分区管控、规划环评、项目环评等制度共同筑牢了生态环境准入的防线,但也出现了管理边界不清晰、管理成效体现不足、制度联动机制保障不健全等问题,本文通过剖析典型规划中生态环境分区管控、规划环评、项目环评三项制度各自发挥的作用,调研部分地区管理实践,提出优化生态环境准入制度的对策建议:一是生态环境分区管控应发挥宏观引领和维护国家生态环境稳定的作用,与国民经济社会发展规划、生态环境保护规划等指导性规划同步研究、同期发布;二是规划环评应进一步筑牢“承上启下”的核心作用,上收部分规划环评的审查权限,提升规划环评文件质量,强化环评要求落实情况监督;三是项目环评应在生态环境准入制度体系中进一步优化简化,对环境影响可控、环保措施成熟的建设项目,可推动项目环评和排污许可两证合一,进一步强化建设主体的责任意识,通过制度整合发挥管理效能。  相似文献   
78.
ARC/INFO对外部数据库的动态访问   总被引:2,自引:0,他引:2  
利用ARC/INFO的DATABASEINTEGRATOR模块功能,实现了在ARC/INFO环境对外部数据库的动态访问?该文就动态连接?访问外部库的条件和方法进行了论述?   相似文献   
79.
Guo Y  Zhang J  Yu R  Zhu KY  Guo Y  Ma E 《Chemosphere》2012,86(7):709-717
Composite samples of Australian farmed Yellowtail Kingfish (Seriola lalandi) (YTKF) (n = 27), Mulloway (Argyrosomus hololepidotus) (n = 6) and manufactured feed (n = 5) were analysed to benchmark levels of a broad range of residues and contaminants of potential public health and trade significance. A subset of these samples [YTKF (n = 5), Mulloway (n = 2) and feed (n = 5)] was analysed for dioxins and polychlorinated biphenyls (PCBs). The mean concentration of dioxins in YTKF was 0.6 pg TEQ g−1 (range 0.22-0.8) and in Mulloway was 0.16 pg TEQ g−1 (range 0.16-0.16). The mean concentration of dioxins and dioxin-like PCBs in YTKF was 2.6 pg TEQ g−1 (range 1.4-3.5), while Mulloway had a mean concentration of 0.67 pg TEQ g−1 (range 0.57-0.76). The mean concentration of PCBs in YTKF was 21 μg kg−1 (range 8.6-29) and in Mulloway was 5.4 μg kg−1 (mean 4.7-6). The mean concentration of dioxin-like PCBs in YTKF was 2.1 pg TEQ g−1 (range 1.2-2.8) and in Mulloway was 0.51 pg TEQ g−1 (range 0.41-0.61). The mean mercury concentration in YTKF was 0.03 mg kg−1 (range 0.02-0.05) and in Mulloway it was 0.02 mg kg−1 (range 0.02-0.04). There were no detectable levels of any pesticide or antimicrobial compounds in any sample of YTKF or Mulloway. Attention is drawn to technical differences in port of entry testing programs such as sampling strategies, portion tested, laboratory methodology, residue definitions and reporting conventions that exporters’ products may be subject to. All residues and contaminants were either undetectable or present at very low levels when judged against Australian, Japanese and European Union regulatory standards (where set).  相似文献   
80.
为合理评价航空公司的飞行安全状态,利用QAR超限事件作为原始数据,运用因子分析法确定评价指标及其重要程度。针对飞行运行的动态性,引入无需确定指标权重的突变级数法构建评价模型;利用某航空公司2015和2016年24个月的QAR数据,使用该模型进行评价,所得的评价结果与该公司的实际飞行安全状态基本相符合。结果表明:基于因子分析与突变级数法的飞行安全状态评价模型可用于实际评价工作中,且评价结果较为真实可靠。  相似文献   
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