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991.
992.
Ricci P.H. Yue Harry F. Lee Melissa A. Hart 《Journal of Environmental Planning and Management》2017,60(6):1073-1091
The human dimensions of visibility degradation remain under-researched academically. Based on Zube and Sell's Process Model of the Perception of, and Response to, Environmental Change, a questionnaire survey was conducted in Hong Kong between 5 June 2012 and 26 January 2013 (n = 1,203). The respondents’ perceptions towards visibility degradation were collected. The results show that respondents were moderately knowledgeable to visibility degradation, perceiving the problem as anthropogenic and unfavorable and identifying the fight against the degradation as an important environmental issue. It is further deduced that the respondents’ physical and sociocultural attributes, and the way they gain information about visibility degradation, can affect their perceptions of visibility degradation. The results reveal that improving information channels can positively promote human sensitivity to and understanding of visibility degradation in order to mitigate it. Yet, any attempts to educate the lay public should not assume the existence of a homogenous community of like-minded people. 相似文献
993.
BLAKE R. HOSSACK MICHAEL J. ADAMS CHRISTOPHER A. PEARL KRISTINE W. WILSON EVELYN L. BULL KRISTIN LOHR DEBRA PATLA DAVID S. PILLIOD JASON M. JONES KEVIN K. WHEELER SAMUEL P. MCKAY PAUL STEPHEN CORN 《Conservation biology》2013,27(6):1410-1420
Despite the high profile of amphibian declines and the increasing threat of drought and fragmentation to aquatic ecosystems, few studies have examined long‐term rates of change for a single species across a large geographic area. We analyzed growth in annual egg‐mass counts of the Columbia spotted frog (Rana luteiventris) across the northwestern United States, an area encompassing 3 genetic clades. On the basis of data collected by multiple partners from 98 water bodies between 1991 and 2011, we used state‐space and linear‐regression models to measure effects of patch characteristics, frequency of summer drought, and wetland restoration on population growth. Abundance increased in the 2 clades with greatest decline history, but declined where populations are considered most secure. Population growth was negatively associated with temporary hydroperiods and landscape modification (measured by the human footprint index), but was similar in modified and natural water bodies. The effect of drought was mediated by the size of the water body: populations in large water bodies maintained positive growth despite drought, whereas drought magnified declines in small water bodies. Rapid growth in restored wetlands in areas of historical population declines provided strong evidence of successful management. Our results highlight the importance of maintaining large areas of habitat and underscore the greater vulnerability of small areas of habitat to environmental stochasticity. Similar long‐term growth rates in modified and natural water bodies and rapid, positive responses to restoration suggest pond construction and other forms of management can effectively increase population growth. These tools are likely to become increasingly important to mitigate effects of increased drought expected from global climate change. Papeles de las Características del Fragmento, Frecuencia de Sequía y Restauración en las Tendencias a Largo Plazo de un Anfibio Ampliamente Distribuido 相似文献
994.
Narita H Abe J Funamizu N Takakuwa T Kunimoto M 《Environmental monitoring and assessment》2007,129(1-3):71-77
Bioassay using cultured human cell lines was applied to an effluent of a wastewater treatment plant (WWTP) in Sapporo to assess
their toxicity, and in order to investigate the fate of toxicity in the WWTP, bioassay of the water samples from several points
in WWTP (influent, effluent, return flow from thickener, from dewatering process and from incineration process) was performed.
We also applied bioassay to the mixture of the activated sludge from the investigated plant and artificial sewage. These results
showed that the toxicity of the effluent was more intensive than the influent, and organic matter released from activated
sludge bacteria during their decay process contributed to the increase of toxicity in the effluent. 相似文献
995.
人类健康风险的定量评估与分析 总被引:1,自引:0,他引:1
通过深入研究.将人类健康风险解析环境污染、食物安全、疾病流行和医疗保障四个方面。在建立一套评价人类健康风险指标体系的基础上。对40个样本国家进行评估。用聚类分析的方法.将40个国家分为四类,在对每一类国家的人类健康风险特点进行对比发现,在同等经济发展水平下,中国的人类健康风险相对较高。通过分析人类健康风险与经济发展水平的关系得出,人均GNI 1000,3000美元是国家经济发展的关键时期。同样也是改善人类健康状况的关键时期,这一时期国家要高度重视改善人类健康状况。 相似文献
996.
Ohmichi K Komiyama M Matsuno Y Takanashi Y Miyamoto H Kadota T Maekawa M Toyama Y Tatsugi Y Kohno T Ohmichi M Mori C 《Environmental science and pollution research international》2006,13(2):120-124
Goal, Scope and Background Cadavers for gross anatomy laboratories are usually prepared by using embalming fluid which contains formaldehyde (FA) as
a principal component. During the process of dissection, FA vapors are emitted from the cadavers, resulting in the exposure
of medical students and their instructors to elevated levels of FA in the laboratory. The American Conference of Governmental
Industrial Hygienists (ACGIH) has set a ceiling limit for FA at 0.3 ppm. In Japan, the Ministry of Health, Labour and Welfare
has set an air quality guideline defining two limit values for environmental exposure to FA: 0.08 ppm as an average for general
workplaces and 0.25 ppm for specific workplaces such as an FA factory. Although there are many reports on indoor FA concentrations
in gross anatomy laboratories, only a few reports have described personal FA exposure levels. The purpose of the present study
was to clarify personal exposure levels as well as indoor FA concentrations in our laboratory in order to investigate the
relationship between them.
Methods The gross anatomy laboratory was evaluated in the 4th, 10th and 18th sessions of 20 laboratory sessions in total over a period
of 10 weeks. Air samples were collected using a diffusive sampling device for organic carbonyl compounds. Area samples were
taken in the center and four corners of the laboratory during the entire time of each session (4-6 hours). Personal samples
were collected from instructors and students using a sampling device pinned on each person's lapel, and they were 1.1 to 6
hours in duration. Analysis was carried out using high performance liquid chromatography.
Results and Discussion Room averages of FA concentrations were 0.45, 0.38 and 0.68 ppm for the 4th, 10th and 18th sessions, respectively, ranging
from 0.23 to 1.03 ppm. These levels were comparable to or relatively lower than the levels reported previously, but were still
higher than the guideline limit for specific workplaces in Japan and the ACGIH ceiling limit. The indoor FA concentrations
varied depending on the contents of laboratory sessions and seemed to increase when body cavity or deep structures were being
dissected. In all sessions but the 4th, FA levels at the center of the room were higher than those in the corners. This might
be related to the arrangement of air supply diffusers and return grills. However, it cannot be ruled out that FA levels in
the corners were lowered by leakage of FA through the doors and windows. Average personal exposure levels were 0.80, 0.45
and 0.51 ppm for instructors and 1.02, 1.08 and 0.89 ppm for students for the 4th, 10th and 18th session, respectively. The
exposure levels of students were significantly higher than the mean indoor FA concentrations in the 4th and 10th sessions,
and the same tendency was also observed in the 18th session. The personal exposure level of instructors was also significantly
higher than the indoor FA level in the 4th session, while they were almost the same in the 10th and 18th sessions. Differences
in behavior during the sessions might reflect the differential personal exposure levels between students and instructors.
Conclusion The present study revealed that, if a person is close to the cadavers during the gross anatomy laboratory, his/her personal
exposure level is possibly 2 to 3-fold higher than the mean indoor FA concentration. This should be considered in the risk
assessment of FA in gross anatomy laboratories.
Recommendation and Outlook If the risk of FA in gross anatomy laboratories is assessed based on the indoor FA levels, the possibility that personal
exposure levels are 2 to 3-fold higher than the mean indoor FA level should be taken into account. Otherwise, the risk should
be assessed based on the personal exposure levels. However, it is hard to measure everyone's exposure level. Therefore, further
studies are necessary to develop a method of personal exposure assessment from the indoor FA concentration. 相似文献
997.
998.
牟勇 《中国安全生产科学技术》2006,2(3):109-111
伤亡赔偿标准由于人的年龄、经历、工作等的不同而不同。本文参考国内外相关资料后,在人人平等的基础上区分了不同人的生命价值,设计的估算方法基本包含了各个年龄段的人的生命价值。估算结果仅适用于事故和不可抗力造成的伤亡情况,不适用于故意伤害谋杀等犯罪活动造成的伤亡。生命价值没有上限只有下限,使生命经济价值的估算值有较大提高,这对提高伤亡赔偿标准,对提高人们对生命价值的认识都有一定的价值。 相似文献
999.
社会保障制度和人力资本投资的关系是近年来劳动经济学中新出现的一个课题,相关研究尚不多见。以我国养老保险的“统帐结合”模式为例,分析了社会保障对人力资本投资的影响,同时结合我国劳动力市场现状,对劳动力市场分割状态下“统帐结合”模式与人力资本投资的关系进行了分析。结果表明,增加“统帐结合”模式中个人账户的比例,将激励个人进行较多的人力资本投资,但劳动力市场分割的存在削弱了这种激励作用。因此,建议:适当增加“统帐结合”模式中个人承担的比例;建立覆盖全国的社会保障体系;加快劳动力市场建设。逐步消除劳动力市场分割状态,促进全国统一的、自由竞争的劳动力市场的形成。 相似文献
1000.
Abstract Based on the flood affected area (FA) data of the provinces in China from 1950 to 2005, the article discusses the change of the flood patterns in China, and investigates its relationship with climate change and human activities. The flood center shifted from North China and the Yangtze–Huaihe basin in the 1950s towards the south, north and west of China, and located in the south of the Yangtze River and South China after the 1990s. The FA in the western provinces was continuously on the rise since the 1950s. There are two characteristics for the future flood pattern in China. The pattern of “flood in the south and drought in the north” depends on the north–south shift of the maximum rainfall region in eastern China. The flood intensification to the west of Hu Huanyong’s line mainly results from the increase of rainfall, extreme precipitation and the melting of glaciers under the background of human activity magnification. 相似文献