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81.
Xunpeng Shi Author Vitae 《Journal of Safety Research》2009,40(3):207-213
Problem
Empirical studies on the effectiveness of workplace safety regulations are inconclusive. This study hypothesizes that the asynchronous effects of safety regulations occur because regulations need time to become effective. Safety regulations will work initially by reducing the most serious accidents, and later by improving overall safety performance.Method
The hypothesis is tested by studying a provincial level aggregate panel dataset for China's coal industry using two different models with different sets of dependent variables: a fixed-effects model on mortality rate, which is defined as fatalities per 1,000 employees; and a negative binominal model on the annual number (frequency) of disastrous accidents.Results
Safety regulations can reduce the frequency of disastrous accidents, but have not reduced mortality rate, which represents overall safety performance.Discussion and summary
Policy recommendations are made, including shifting production from small to large mines through industrial consolidation, improving the safety performance of large mines, addressing consequences of decentralization, and facilitating the implementation of regulations through carrying on institutional actions and supporting legislation.Impact on industry
Until recently, about 4,000 coal miners perished annually in China, demonstrating that workplace safety in China's coal industry is an urgent and important issue. This research provides evidence that safety regulations have asynchronous effects and identifies the priorities in improving safety in China's current coal mining. This may assist the Chinese government to design more effective safety improvement policies and improve the effectiveness of safety regulations and safety performance. 相似文献82.
To analyze the factors affecting US public concern about the threat of climate change between January 2002 and December 2013, data from 74 separate surveys are used to construct quarterly measures of public concern over global climate change. Five factors should account for changes in levels of concern: extreme weather events, public access to accurate scientific information, media coverage, elite cues, and movement/countermovement advocacy. Structural equation modeling indicates that elite cues, movement advocacy efforts, weather, and structural economic factors influence the level of public concern about climate change. While media coverage exerts an important influence, it is itself largely a function of elite cues and economic factors. Promulgation to the public of scientific information on climate change has no effect. Information-based science advocacy has had only a minor effect on public concern, while political mobilization by elites and advocacy groups is critical in influencing climate change concern. 相似文献
83.
为检验二元联合作用藻红外测试方法的可行性,用Cu~(2+)、Fe3+、Mn~(2+)、Al3+、Cr3+、Hg~(2+)、Cd~(2+)、Pb~(2+)、Zn~(2+)进行了二元联合作用测试实验。结果显示:联合药液的参照浓度与单药液的参照浓度比为0.5:0.25的有15组二元组合,为2.0:1.0的有10组二元组合,为1.0:0.5的有11组二元组合;在9种重金属的36组二元联合作用测试结果中出现拮抗作用、相加作用、协同作用,表明联合作用类型表现出多样性;14组拮抗作用中单组的再现性为50%~100%、多组的再现性的出现率为93%、单组的重现性为67%~100%、多组的重现性的出现率为100%,21组相加作用中单组的再现性为50%~100%、多组的再现性的出现率为86%、单组的重现性为67%~100%、多组的重现性的出现率为100%,1组协同作用重现性67%;36组联合作用测试结果的再现性为50%~100%、再现性的出现率为86%,重现性为67%~100%、重现性的出现率为100%。上述分析可知,9种重金属的36种二元联合作用测试结果具有较好的多样性、再现性、重现性,表明测试条件、藻温测试方法、三指标评价法能够保证藻响应温差和藻响应药品评价结果的质量,参照浓度分析方法、联合作用评价方法能够控制联合作用分析结果的质量;藻响应的有毒有害物都存在敏感浓度,用参照浓度分析方法可分析出藻响应有毒有害物的参照浓度。因此,藻红外测试技术可以用于测试重金属、农药、有机药品、抗生素等的二元联合作用。 相似文献
84.
Ruixin Guo Xinkun Ren Hongqiang Ren 《Journal of environmental science and health. Part. B》2013,48(9):883-890
As important members of the zooplankton community and sources of food for fish, rotifers are used extensively in ecotoxicological research to assess the health of the environment and safety of compounds. However, most rotifer toxicity tests are only conducted using rotifer neonates derived from unexposed mothers, thus ignoring the potential transfer of contaminants from mother to offspring. To understand better the mother to offspring exposure, a multigenerational study was conducted using three successive generations (F0, F1 and F2) of the common freshwater rotifer Brachionus calyciflorus to investigate the toxic effects of the widely used organophosphate pesticide, dimethoate (O, O-dimethyl S-methylcarbamoylmethyl phosphorodithioate). When the F0 generation was exposed to five pesticide concentrations, the population growth rate (r) displayed symptoms of hormesis, characterized by the conversion of low-concentration stimulation to high-concentration inhibition. Despite this observation, the exposure to any given concentration of dimethoate reduced the population growth rates of the F1 and F2 generation rotifers. Significant differences existed between the F0, F1 and F2 rotifers for the population growth rate under dimethoate stress: F2 individuals were more sensitive than F1, whereas the F1 individuals were more sensitive than F0. The results indicated that the parental exposure to a given toxic stress could result in increased sensitivity and decreased fitness in the offspring. This study illustrates the utility of multigenerational toxicity tests, which may better reflect and more accurately predict the effects of long-term pesticide exposure to aquatic organisms at the population level. 相似文献
85.
Salmon aquaculture has emerged as a successful economic industry generating high economic revenues to invest in the development of Chiloe region, Southern Chile. However, salmon aquaculture also consumes a substantial amount of ecosystem services, and the direct and indirect impacts on human wellbeing are still unknown and unexplored. This paper identifies the synergies and trade-offs caused by the salmon industry on a range of ecosystem services. The results show that large economic benefits due to the increase of provisioning ecosystem services are also causing a reduction on regulating and cultural services. Despite the improvement on average income and poverty levels experienced in communities closely associated with the sector, this progress is not large enough and social welfare did not improve substantially over the last decade. The rest of human wellbeing constituents in Chiloe region have not changed significantly compared to the development in the rest of the country. 相似文献
86.
Analyzing the cost effectiveness of Santiago, Chile's policy of using urban forests to improve air quality 总被引:4,自引:0,他引:4
Escobedo FJ Wagner JE Nowak DJ De la Maza CL Rodriguez M Crane DE 《Journal of environmental management》2008,86(1):148-157
Santiago, Chile has the distinction of having among the worst urban air pollution problems in Latin America. As part of an atmospheric pollution reduction plan, the Santiago Regional Metropolitan government defined an environmental policy goal of using urban forests to remove particulate matter less than 10 microm (PM(10)) in the Gran Santiago area. We used cost effectiveness, or the process of establishing costs and selecting least cost alternatives for obtaining a defined policy goal of PM(10) removal, to analyze this policy goal. For this study, we quantified PM(10) removal by Santiago's urban forests based on socioeconomic strata and using field and real-time pollution and climate data via a dry deposition urban forest effects model. Municipal urban forest management costs were estimated using management cost surveys and Chilean Ministry of Planning and Cooperation documents. Results indicate that managing municipal urban forests (trees, shrubs, and grass whose management is under the jurisdiction of Santiago's 36 municipalities) to remove PM(10) was a cost-effective policy for abating PM(10) based on criteria set by the World Bank. In addition, we compared the cost effectiveness of managing municipal urban forests and street trees to other control policies (e.g. alternative fuels) to abate PM(10) in Santiago and determined that municipal urban forest management efficiency was similar to these other air quality improvement measures. 相似文献
87.
We applied the complex ecosystem model EMMO, which was adopted to the shallow lake Müggelsee (Germany), in order to evaluate a large set of ecological scenarios. By means of EMMO, 33 scenarios and 17 indicators were defined to characterize their effects on the lake ecosystem. The indicators were based on model outputs of EMMO and can be separated into biological indicators, such as chlorophyll-a and cyanobacteria, and hydro-chemical indicators, such as phosphorus. The question to be solved was, what is the ranking of the scenarios based on their characterization by these 17 indicators? And how can we handle high quantities of complex data within evaluation procedures? The scenario evaluation was performed by partial order theory which, however, did not provide a clear result. By subsequently applying the hierarchical cluster analysis (complete linkage) it was possible to reduce the data matrix to indicator and scenario representatives. Even though this step implies losses of information, it simplifies the application of partial order theory and the post processing by METEOR. METEOR is derived from partial order theory and allows the stepwise aggregation of indicators, which subsequently leads to a distinct and clear decision. In the final evaluation result the best scenario was the one which defines a minimum nutrient input and no phosphorus release from the sediment while the worst scenario is characterized by a maximum nutrient input and extensive phosphorus release from the sediment. The reasonable and comprehensive results show that the combination of partial order, cluster analysis and METEOR can handle big amounts of data in a very clear and transparent way, and therefore is ideal in the context of complex ecosystem models, like that we applied. 相似文献
88.
89.
Milan Stra
kraba 《Ecological modelling》2001,140(3)
Based on cybernetic categories of natural control mechanisms, four generations of ecosystem models are distinguished: feed-forward, feedback, self-adaptation and self-organization models. The analysis of the natural control mechanisms in aquatic ecosystems suggests that different processes are controlled in different ways, and, although the four mechanisms were identified in historical sequence, they all operate simultaneously. The concept of self-organization of an ecosystem is introduced and specified for a model of an aquatic pelagic ecosystem. The concept of the ecosystem as a multilayer, multigoal and multiechelon hierarchical system with hierarchy of the levels of biological organization is also introduced. 相似文献
90.
Montane Meadows as Indicators of Environmental Change 总被引:1,自引:0,他引:1
Diane M. Debinski Mark E. Jakubauskas Kelly Kindscher 《Environmental monitoring and assessment》2000,64(1):213-225
We used a time series of satellite multispectral imagery for mapping and monitoring six classes of montane meadows arrayed along a moisture gradient (from hydric to mesic to xeric). We hypothesized that mesic meadows would support the highest species diversity of plants, birds, and butterflies because they are more moderate environments. We also hypothesized that mesic meadows would exhibit the greatest seasonal and interannual variability in spectral response across years. Field sampling in each of the meadow types was conducted for plants, birds, and butterflies in 1997 and 1998. Mesic meadows supported the highest plant species diversity, but there was no significant difference in bird or butterfly species diversity among meadow types. These data show that it may be easier to detect significant differences in more species rich taxa (e.g., plants) than taxa that are represented by fewer species (e.g., butterflies and birds). Mesic meadows also showed the greatest seasonal and interannual variability in spectral response. Given the rich biodiversity of mesic montane meadows and their sensitivity to variations in temperature and moisture, they may be important to monitor in the context of environmental change 相似文献