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311.
围绕如何测度并改善天然气安全这一核心议题,引入并修正了APERC能源安全“4A”分析框架,运用层次分析法与德尔斐法,构建了天然气安全评价指标体系,对主要天然气净进口国和净出口国的天然气安全状况进行了量化评估。评估发现:(1)天然气安全四维度(资源可利用性、经济可承受性、贸易可获得性与环境可接受性)的不可或缺性意味着综合表现优异的国家安全水平更高;(2)8个二级指标中,可采储量、个体可承受性等指标的权重更大;(3)天然气净出口国在资源可利用性、经济可承受性和贸易可获得性方面有优势,整体表现优于进口国。就中国而言,可从加快资源开发、完善市场机制、扩大进口渠道和提高资源利用效率四个方面提高天然气安全水平。 相似文献
312.
313.
Barbara Wyrzykowska Jerzy Falandysz Grażyna Jarzyńska 《Journal of environmental science and health. Part. B》2013,48(4):296-305
Metals including Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, Pb, Sr and Zn were determined in muscle tissue of 12 fish species by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and cold vapour-atomic absorption spectroscopy (CV-AAS). Fish were collected from Vistula River at lower course and Dead Vistula River channel in south of Baltic Sea in Poland. The fish species examined include Round Goby (Neogobius melanostomus), Crucian Carp (Carassius carassius), Bull-rout (Myoxocephalus scorpius), Tench (Tinca tinca), Bream (Abramis brama), Burbot (Lota lot), Perch (Perca perca), Roach (Rutilus rutilus), Silver Carp (Hypophthalmichthys molitrix), Pikeperch (Stizostediun lucioperca), Brown salmon (Salmo trutta m. Trutta) and Eel (Anguilla anguilla). The median values of metal concentrations in fresh muscle tissue of 11 fish species varied as follows: Al < 0.5–60; Ba < 0.05–0.31; Ca 120–1800; Cd < 0.05–0.096; Co < 0.10; Cr < 0.10–0.50; Cu < 0.15–0.77; Fe 1.5–21; Hg 0.0058–0.65; K 1800–4200; Mg 130–560; Mn 0.12–0.59; Na 350–840; Ni < 0.2–0.31; Pb < 0.75; Sr 0.079–2.9; Zn 3.3–23 μg/g fresh weight. The Target Hazard Quotient (THQ) values calculated in this study for Cd and Hg from muscles of fish species collected from Vistula River were low in the range of 0.4 for Hg and 0.8 for Cd. Supplemental materials are available for this article. Go to the publisher's online edition of Journal of Environmental Science and Health, Part B to view the free supplemental file. 相似文献
314.
Karlah Rae Rudolph 《Local Environment》2013,18(9):1079-1098
A food crisis confronts many Indigenous communities in northwestern Canada, as reflected by wide-scale food insecurity and diet-related disease. South-generated responses to this crisis generally disregard principles of Indigenous food sovereignty and are disengaged from concerns related to environmental and food justice. This study seeks to explore the needs and priorities of a First Nation (Misipawistik Cree Nation) and an associated Métis community (Grand Rapids) regarding existing and potential responses to the food crisis in northern Manitoba. Substantial changes to the traditional food system were initiated during the establishment of the reserve system in the 1800s and now extend to damage associated with hydro development. Responses to these changes were categorised according to themes and include the revival of country food traditions, individual and community gardens, agriculture in the North, and better quality imported foods. Regardless of response, decision-making needs to be community-driven, culturally appropriate, to reflect local priorities in order to effectively address the northern food crisis, and, ultimately, needs to work towards Indigenous food sovereignty to be effective. 相似文献
315.
P. Neuhaus 《Behavioral ecology and sociobiology》2000,48(1):75-83
I studied reproductive costs in the female Columbian ground squirrel (Spermophilus columbianus) using individually marked animals. I compared weight changes during the active season and over winter, and mortality for
females that did and did not wean young. Females raising young were heavier at emergence in that spring than unsuccessful
ones. Females that did not raise young gained more weight during summer, were heavier than successful females at the time
of entry into hibernation, and were heavier emerging from hibernation the following spring. Over-winter mortality was higher
for females that reared young compared to reproductively unsuccessful females. A food supplementation experiment showed that
energy-rich food can accelerate individuals’ weight gain. Interactions between litter size, birth weight, weight at emergence
from the natal burrow, survival of young to yearling age, and maternal fitness were also studied. Litter sizes were experimentally
manipulated to evaluate how females cope with costs of rearing one additional young. Birth weight of juveniles was positively
correlated with survival to emergence from the natal burrow and with survival to yearling age. Partial litter loss was higher
in experimentally enlarged litters than in either experimentally decreased or control litters. Total litter loss, survival
of adult females or the probability of weaning young the following year were not affected by the litter size manipulation.
Females appear to adjust the size of their litter before birth, and to some extent during lactation, to their ability to wean
young.
Received: 20 January 2000 / Received in revised form: 12 March 2000 / Accepted: 18 March 2000 相似文献
316.
Abstract: Marine protected areas (MPAs) are a popular conservation strategy, but their impacts on human welfare are poorly understood. To inform future research and policy decisions, we reviewed the scientific literature to assess MPA impacts on five indicators of human welfare: food security, resource rights, employment, community organization, and income. Following MPA establishment, food security generally remained stable or increased in older and smaller MPAs. The ability of most fishing groups to govern MPA resources changed. Increased resource rights were positively correlated with MPA zoning and compliance with MPA regulations. Small sample sizes precluded statistical tests of the impacts of MPAs on employment, community organization, and income. Our results demonstrate that MPAs shape the social well‐being and political power of fishing communities; impacts (positive and negative) vary within and among social groups; and social impacts are correlated with some—but not all—commonly hypothesized explanatory factors. Accordingly, MPAs may represent a viable strategy for enhancing food security and empowering local communities, but current practices negatively affect at least a minority of fishers. To inform policy making, further research must better document and explain variation in the positive and negative social impacts of MPAs. 相似文献
317.
目前我国新农村环境形势十分严峻,环境教育薄弱是一个重要的原因.农村环境教育是我国环境教育的重要组成部分,也是当前我国环境保护和环境教育工作的重点.设计切实可行的教育方案是成功实施农村环境教育的关键.在论述环境教育意义的基础上,分析了强化平台基地建设和推进环境信息公开,在农村环境宣传教育中的基础作用.设计了领导干部和公务员、乡镇企业领导和员工、农民、城镇居民、大学生和未成年人等五大重点群体环境教育方案,提出了确保环境教育取得实效的长效保障机制对策建议. 相似文献
318.
A Yin‐Yang approach to education policy regarding health and the environment: early‐careerists' image of the future and priority programmes
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Paul Watts Benjamin Custer Zhuang‐Fang Yi Enoch Ontiri Marivic Pajaro 《Natural resources forum》2015,39(3-4):202-213
Since the inception of sustainable development (SD), there has been a somewhat ignored contradiction between paradigms that are ecosystem‐based and paradigms that are human‐based or purely economic. We suggest that this contradiction can be unified through a balance of the two. The Chinese Yin‐Yang philosophy is applied as a tool or approach to seeking balance between these ecocentric and anthropocentric paradigms. Priority education policy design for the merging of ecology and health are projected through an Ecohealth lens in response to increasing SD challenges and the intention of the international Ecohealth organization to contribute to SD goals. Meeting SD goals along the nexus of health and environment is further considered through early‐careerist cultural assessments and projections. The groups considered for their professional image of the future are: members of the Ecohealth Association Student Section and Chinese early‐careerists participating in a related conference. In response to SD goals, a problem‐based learning design is suggested as an education policy priority. Rather than approaching SD as a boolean concept, for example, by either focusing on ecosystem sustainability or economic development, we suggest education policy for programmes and curriculums that will help emerging professionals balance these paradigms, so as to best address national and global challenges. 相似文献
319.
为评估机场旅客安检系统的保障能力,并针对评估过程中存在的不确定性和指标中影响因素之间的不独立性,采用模糊网络分析法(Fuzzy-ANP)建立系统评估模型。在综合考虑安检影响因素的前提下,从人、机、环、管四方面建立了机场旅客安检系统保障能力评估指标体系。以某机场为例,应用模型进行实证分析得出结论,影响该机场旅客安检系统保障能力的主要因素为员工工作量、员工心理状况和设备完好率。研究表明,评价结果与该机场实际运营状况相符合,该方法能更好地满足机场运营安全管理的实际要求。 相似文献
320.
<正>Introduction Cadmium is considered a human carcinogen by the International Agency for Research on Cancer(IARC,1993)and the US National Toxicology Program(NTP,1997).Cadmium contamination of food crops is a persistent issue for both the agricultural industry as well as consumers.This is an issue for agriculture because cadmium can be present in soils naturally or as a result of industrial processes and can contaminate foods that are consumed by humans.Industrial 相似文献