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41.
完善生态影响评估 促进中国生态资源的保护   总被引:4,自引:0,他引:4  
环境影响评估对减少工业和城市发展对环境的影响起到了一定的作用,但目前的环境影响评估工作比较重视发展项目对其周围水、气污染方面的评估,对自然资源影响的评估还未受到足够的重视,文章对生态影响评估的重要性及中国内地生态影响评估的现状进行了简要的讨论,并介绍了香港生态影响评估系统,以为我国同地生态影响评估工作的管理提供参考。  相似文献   
42.
Environmental personalization and elementary school children's self-esteem   总被引:1,自引:0,他引:1  
Prior research indicates that the physical classroom environment has the potential to affect children's behaviors, academic performance, and cognitive development. However, less is understood about the effect on the socio-emotional development of children. This study investigates the potential role of one aspect of the classroom's physical environment, personalization displays, on children's self-esteem. The study employed a classroom intervention in a quasi-experiment to examine the effects of increasing environmental personalization on children's self-esteem. Thirty-eight kindergarteners and first graders in six classrooms of two elementary schools in a rural community of a north-eastern state were assessed on pretests and post-tests of the Self-Esteem Index (SEI) scale and the Children's Inventory of Self-Esteem (CISE) scale. The findings were mixed but encouraging. On both measures of self-esteem, there was a significant positive effect of classroom personalization for first graders. However, for kindergarteners there was a significant positive effect for only one measure, the CISE. Although there are limitations with the study design, the findings suggest that young children's self-esteem may be influenced and enhanced by specific aspects of the classroom's physical environment.  相似文献   
43.
Although solar farms are often favorably received by the public due to their contribution to clean energy, they are not conflict-free. In various contexts, this land-intensive technology often competes with other land uses like agriculture, nature reserves, and army training. As a result of this competition, interest groups often seek political leverage in order to prioritize their spatial use. Framing their uses as existential is one possible way to capture the attention of decision-makers. Yet, this securitization process may create a framing contest whereby different actors use similar securitization language to promote different land uses. This study is the first attempt to trace how this framing contest of securitized discourses over land appropriation is constructed. It is based on the Israeli experience of promoting solar energy in the Negev Desert, an area conceived as available to solar development. Through an analysis of protocols of Israeli policy-makers’ meetings between 2002 and 2011, the study documents the ways in which players adopt securitized language concerning various land uses such as energy, food, ecology, and traditional (national) security. The study found that the use of securitized framing varies between uses, forums, actors, and sectors. Yet competition between securities discourses remained uneven as, in the Israeli context, many players find it difficult to challenge the hegemonic role of traditional (national) security.  相似文献   
44.
The objective of this study was to investigate changes in the levels of toxic and essential elements in maternal blood during pregnancy and subsequently. A subset of 211 pregnant women from the North Norwegian Mother-and-Child Study was included. Blood samples were collected during the 2(nd) trimester (P1) and postpartum (day 3, P2; and 6 weeks, P3) in different regions of northern Norway, and were analyzed for a suite of 10 selected elements. The latter feature three general but distinct concentration patterns across the three collection periods, namely: progressive increase [Group 1: As, Cd (non-smokers only), Mn, Pb and Zn]; V-shaped, with a minimum at P2 [Group 2: Cd (smokers), Hg, Mo and Se]; and downward V, with a maximum at P2 [Group 3: Co and Cu]. These trends are interpreted in the context of underlying metabolic, hematological and physiological changes that occur in mothers, as well the biochemistry and accumulation preferences of these elements within the whole blood compartment and breast milk. Implications for biomonitoring strategies are discussed. In a multivariable analysis of the P1 data, fish consumption was a robust positive predictor for Hg (p < 0.02), As (p < 0.01) and Se (p ≤ 0.001) blood concentrations, multivitamin intake for Se (p < 0.001), and parity for Co (p < 0.002); age reached significance only for Hg (p < 0.001). An inverse association was observed between parity and Hg (p < 0.05). For the other elements, predictor patterns were not evident.  相似文献   
45.
In its role as a competitive producer of phosphate and potash Jordan has not suffered noticeably from the Resource Curse over the past 50 years. However, the effects on its economy because of its geographical proximity to major oil-producing states have been both positive and negative. It is arguable that an oil resource curse has applied to Jordan.  相似文献   
46.
Research is described that constitutes an extension of an earlier paper (J. Environ. Monit., 2001, 3, 177-184), in which concentrations were measured in 263 human placentas of 11 essential elements (P, Ca, Mg, Cu, S, Na, Fe, Zn, K, Se, Mn) and 5 toxic elements (Ba, Sr, Pb, Ni, Cd). The additional data considered derive from earlier visits to 4 of the original 6 communities and 3 others, all but one of which are located in northern Norway and neighbouring areas of Russia. This more than doubled the number of placental samples available (263 to 571). Unfortunately, the personal, life-style and morphometric information obtained for the first study group was not available for the additional mothers. Country differences were evident for all elements except Ba, Fe and Zn; Cd, Cu, Mn, Na, Se, Ni, Pb, Sr and S were higher and K, P, Ca and Mg were lower in Russia (p < 0.03). Not unexpectedly, the highest median lead concentration was observed for the largest city in the western arctic region of Russia, namely Murmansk. Similarly, the higher median nickel level observed for Russia reflects the established observation that urinary nickel concentrations are higher in the Russian than in the Norwegian communities. Even though sampling was performed at different times of the year and before and after a 3-year interval in four centres, inter-collection differences were of relatively small magnitude and appear not to be linked to seasonal or temporal changes. Principal component analysis (PCA) confirmed the prominence of Factor 1, which grouped those metals that are known to form insoluble phosphate complexes and whose concentrations showed a dependence on gestational age and maternal smoking in the earlier study. It is concluded that PCA is a powerful statistical tool for exploring and identifying fundamental pathways and processes involved in governing the inorganic elemental composition of placental tissue. It also has the potential of identifying study limitations and quality assurance shortfalls. Further our findings show promise that placental concentrations of toxic elements may serve as an index of exposure and of nutritional intake for selected essential micro-elements.  相似文献   
47.
Phosphorus (P) runoff from fields fertilized with swine (Sus scrofa) manure has been implicated in eutrophication. Dietary modification and manure amendments have been identified as best management practices to reduce P runoff from manure. This study was conducted to compare the effects of dietary modification and aluminum chloride (AlCl3) manure amendments on reducing P in swine manure and runoff. Twenty-four pens of nursery swine were fed either a normal diet or a phytase-amended diet. Each pen was connected to a separate manure pit, which was treated with AlCl3 to give final concentrations in the liquid manure of 0 (control), 0.25, 0.50, or 0.75% (v/v). Manure was collected and applied to plots cropped with tall fescue (Festuca arundinacea Schreb.), and simulated rainfall was applied at 50 mm h(-1), sufficient to generate a minimum of 30 min of continuous runoff. Samples of manure and runoff were analyzed for P and Al concentrations. Phytase reduced manure soluble reactive phosphorus (SRP) by 17%, while AlCl3 reduced manure SRP by as much as 73% compared with normal manure. Phosphorus runoff was reduced from 5.7 to 2.6 mg P L(-1) (a 53% reduction) using AlCl3. The mean SRP concentration in runoff from phytase diets without AlCl3 was 7.1 mg P L(-1) during the first rainfall simulation. When phytase and AlCl3 were used together, both manure SRP and P runoff were reduced more than if either treatment were used without the benefit of the other. Use of AlCl3 did not increase soluble Al in manure or Al lost in runoff. Results from this study indicate that producers should use dietary manipulation with phytase and AlCl3 manure amendments to reduce potential P losses from fields fertilized with swine manure.  相似文献   
48.
As with several other metals, the recession of the early 1990s combined with events in the former Soviet Union, placed major strains on the world nickel market and made the operation of several established mines uneconomic. The subsequent world economic recovery, combined with the emergence of new mining and processing technologies, seems at face value to have opened the way for new and expanded nickel mines in Western Australia to expand their share of world production. Against the background of an established oligopolistic market structure and major nickel finds elsewhere, this study assesses the likelihood of major new nickel developments taking place.  相似文献   
49.
ABSTRACT: An analogue method of ex post evaluation is proposed as a method of measuring the effectiveness of small watershed projects in obtaining flood control and economic benefits. Two watersheds were compared on a “with vs. without” project basis by both direct and indirect measurement of economic benefits. Direct measurements indicated that small watershed flood control projects did not generate the expected economic benefits. However, the indirect measurements of the same watersheds using land value enhancement as a surrogate suggested that the expected economic benefits were reflected in differential land values. The economic efficiency of small watershed projects should be measured ex ante and ex post on a “with vs. without” project basis rather than on a “before vs. after” basis whether using direct or surrogate variables.  相似文献   
50.
Objective: Despite successes in the 1980s and early 1990s, progress in reducing impaired driving fatalities in the United States has stagnated in recent years. Since 1997, the percentage of drivers involved in fatal crashes with illegal blood alcohol concentration (BAC) levels has remained at approximately 20 to 22%. Many experts believe that public complacency, competing social and public health issues, and the lack of political fortitude have all contributed to this stagnation. The number of alcohol-related crashes, injuries, and fatalities is still unacceptable, and most are preventable. The public needs to be aware that the problem presented by drinking drivers has not been solved. Political leaders need guidance on which measures will affect the problem, and stakeholders need to be motivated once again to implement effective strategies.

Methods: The National Academy of Sciences (NAS) Transportation Research Board (TRB), Alcohol, Other Drugs, and Transportation Committee (ANB50) sponsored a workshop held at the NAS facility in Woods Hole, Massachusetts, on August 24–25, 2015, to discuss the lack of progress in reducing impaired driving and to make recommendations for future progress. A total of 26 experts in research and policy related to alcohol-impaired driving participated in the workshop. The workshop began by examining the static situation in the rate of alcohol-impaired driving fatal crashes to determine what factors may be inhibiting further progress. The workshop then discussed 8 effective strategies that have not been fully implemented in the United States. Workshop participants (16 of the 26) rated their top 3 strategies.

Results: 3 strategies received the most support: 1. Impose administrative sanctions for drivers with BACs = 0.05 to 0.08 g/dL.

2. Require alcohol ignition interlocks for all alcohol-impaired driving offenders.

3. Increase the frequency of sobriety checkpoints, including enacting legislation to allow them in the 11 states that currently prohibit them.

5 other important strategies included the following: (1) increase alcohol taxes to raise the price and reduce alcohol consumption; (2) reengage the public and raise the priority of impaired driving; (3) lower the illegal per se BAC limit to 0.05 for a criminal offense; (4) develop and implement in-vehicle alcohol detection systems; and (5) expand the use of screening and brief interventions in medical facilities.

Conclusions: Each of these strategies is proven to be effective, yet all are substantially underutilized. Each is used in some jurisdictions in the United States or Canada, but none is used extensively. Any one of the 3 strategies implemented on a widespread basis would decrease impaired driving crashes, injuries, and fatalities. Based on the research, all 3 together would have a substantial impact on the problem.  相似文献   

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