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81.
Energy efficiency and conservation for individual Americans 总被引:1,自引:0,他引:1
D. Pimentel Jennifer Gardner Adam Bonnifield Ximena Garcia Julie Grufferman Claire Horan Julia Schlenker Emily Walling Emily Rochon 《Environment, Development and Sustainability》2009,11(3):523-546
Americans make up only 4% of the world population, yet currently consume 25% of the world’s fossil fuels. The U.S. imports
63% of its oil and it is predicted that by 2020 the U.S. will be importing 95% of its oil resources. Over the past century,
ample and affordable supplies of fossil fuels have powered the growth and prosperity of the economies of the US and other
countries. Within this century, world oil supplies will decline while demand is projected to continue to increase, suggesting
that we will have to transition to different fuels or become much more energy efficient or both. Looking ahead to the near
decades, estimates are that consumers will have to reduce their energy use by at least 50%. This reduction will be necessary
in large part due the decline in the availability of conventional oil and gas, but also because the U.S. population will continue
to grow in number. Although government action is important, individuals too often discount their ability to make significant
contributions to solving such major problems. This investigation identifies how informed and concerned individuals can collectively
conserve fossil energy.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.
An erratum to this article can be found at 相似文献
82.
This paper examines and compares the management practices and regulatory approaches used by the Mid-Atlantic States of Delaware, Maryland, New Jersey, and Pennsylvania for improving the quality of storm-water runoff. Such practices range from simple extended detention criteria in Pennsylvania through the BMP credit system used by Maryland, to the latest "green technology" methods promoted in Delaware and the recharge, quality and peak reduction approaches of New Jersey. All practices are designed to meet EPA requirements for total suspended solids (TSS) removal, but verification of performance is not required. More sophisticated methods of evaluating TSS removal that can be used for engineering design purposes are needed. 相似文献
83.
Many “natural” areas are exposed to military or recreational off-road vehicles. The interactive effects of different types
of vehicular disturbance on vegetation have rarely been examined, and it has been proposed that some vegetation types are
less susceptible to vehicular disturbance than others. At Fort Riley, Kansas, we experimentally tested how different plant
community types changed after disturbance from an M1A1 Abrams tank driven at different speeds and turning angles during different
seasons. The greatest vegetation change was observed because of driving in the spring in wet soils and the interaction of
turning while driving fast (vegetation change was measured with Bray-Curtis dissimilarity). We found that less vegetation
change occurred in communities with high amounts of native prairie vegetation than in communities with high amounts of introduced
C3 grasses, which is the first experimental evidence we are aware of that suggests plant communities dominated by introduced
C3 grasses changed more because of vehicular disturbance than communities dominated by native prairie grasses. We also found
that vegetation changed linearly with vehicular disturbance intensity, suggesting that at least initially there was no catastrophic
shift in vegetation beyond a certain disturbance intensity threshold. Overall, the intensity of vehicular disturbance appeared
to play the greatest role in vegetation change, but the plant community type also played a strong role and this should be
considered in land use planning. The reasons for greater vegetation change in introduced C3 grass dominated areas deserve further study. 相似文献
84.
In the wake of the failures to date of well-publicized multilateral and multi-sectoral mitigation efforts to control greenhouse gases, attention is now increasingly focused on the effectiveness and capacity of national and sub-national level sectoral plans, including forestry, to usher in a new era of adaptation efforts. In Canada, the government of British Columbia spent several years developing its Future Forest Ecosystems Initiative as part of a larger climate change response strategy in the forest sector. Similarly, in the United States, wildfire related events have led to climate change inspired efforts by individual states (e.g., Alaska, California) and the US Forest Service has recently undertaken plans to incorporate climate change considerations in national forest planning beginning with the National Road Map for Responding to Climate Change. This paper highlights a number of shortcomings with both these national and sub-national strategies with respect to the relationships existing between governance, forestry and climate change. It proposes incorporating considerations of governance mechanisms directly into forest sector planning and the need to assess not only natural system level changes but also the extent to which new problems can be dealt with by ‘old’ or ‘new’ governance arrangements. 相似文献
85.
86.
英国按照《职业安全和卫生法(1974)》,以职业安全卫生执行局(HSE)为执法和调查统计的主管机构,建立了以RIDDOR95规程为基础的企业雇主对其作业场所职业卫生记录和报告制度,同时HSE采取多种形式的政府主动调查,形成了较为完善的职业卫生调查统计体系。目前,我国职业卫生的调查统计体系尚未形成。以系统的方法和思路,从英国的职业卫生法规、监管入手,分析其调查统计体系,并采用对比分析的方法,将英国的体系与美国进行对比,学习工业发达国家的共同经验,为我国建立职业卫生统计体系提供借鉴。研究认为,上层法律及配套规范齐全、形成了政府主动调查与企业雇主主动记录和报告相结合的统计方式,以及调查统计数据定期向公众发布和实现信息共享是英美两国体系的共同特征。 相似文献
87.
Diem JE 《Environmental management》2002,29(3):373-384
This paper examines possible ozone-induced foliar injury to ponderosa pine areas in the Rincon Mountains of southern Arizona
from 1972 to 1992. Spatiotemporal differences in a satellite-derived vegetation index (VI) are examined with respect to antecedent
moisture conditions, temporal variations in ozone exposure levels, and measured foliar injury values from 1985. Seasonal ozone
exposure levels (SUM60 and W126) increased from 1982 to 1998 and were significantly correlated (r = 0.49 and 0.53, α= 0.05) with annual population totals in the Tucson area. Extensive masking of satellite images from 1972, 1986,
and 1992 resulted in two optimal change detection areas, with one site, TVWMica, exposed mostly to the Tucson air pollution
plume, while the other site, EMica, was more protected from Tucson-derived pollution. An overall increase in VI from 1972
to 1992 at both sites appears to have been caused by an increase in moisture availability. Larger foliar injury values in
1985 were associated with a smaller increase in VI (i.e., a smaller increase in green leaf biomass) from 1972 to 1986. From
1972 to 1986 and from 1986 to 1992, VI values at TV/WMica increased at a slower rate compared to those at EMica. The reduced
increase in “green-up” may have been caused partially by ozone-induced foliar injury and resulting decreases in green leaf
biomass. However, these spatial differences in VI values may have also been caused by a number of other factors. Results nevertheless
reveal the strong possibility of distinct, topographically based, spatial variations in ozone-induced foliar injury within
the Rincons. 相似文献
88.
Demand for information that can be used to manage loggerhead shrikes has recently increased because of concern over declining
populations and loss of open, non-forested habitat. A previously-developed habitat model was modified to predict shrike habitat
quality on Fort Riley Military Reservation (FRMR) in Kansas. Shrike habitat suitability indices were calculated based on the
amount of potential and usable foraging habitat, and the number of potential nesting sites within a specified area. Interpretation
of high quality digital photographs was used to delineate land cover classes, hedgerows and tree counts. These data were entered
into a geographic information system (GIS) as individual data sets. The shrike habitat model was then employed to produce
a GIS database predicting low, moderate, and high quality shrike habitat throughout the Reservation. Model results indicated
that 67% of the Reservation was suitable habitat for loggerhead shrikes. Although over 80% of FRMR was mapped as grassland,
the presence of few to several isolated trees or hedgerows was identified as a key factor in modeling habitat suitability.
The accuracy of the GIS model was 82% in predicting suitable (moderate and high quality) loggerhead shrike habitat using an
independent set of 66 recent shrike observations. The number of potential nesting sites and percent cover of usable foraging
habitat were significantly related to habitat suitability of the sites occupied by shrikes. 相似文献
89.
近年来 ,公路运输业得到了迅速发展 ,但因我国公路增长速度严重滞后于车辆的增长速度 ,交通运输环境的发展势态变得十分严峻 ,对公路军事运输安全也构成了新的威胁。为了适应市场经济发展的新形势 ,不断改进公路军事运输安全工作 ,笔者从我国公路交通现状出发 ,分析了军车驾驶员的基本状况、不良心理及军队运输安全管理中存在的问题 ,提出了军车驾驶员应具备的素质和运输安全管理对策 相似文献
90.
Human health risk assessment of explosives and heavy metals at a military gunnery range 总被引:1,自引:0,他引:1
In this research, a risk assessment was undertaken in order to develop the remediation and management strategy of a contaminated
gunnery site, where a nearby flood controlling reservoir is under construction. Six chemicals, including explosives and heavy
metals, posing potential risk to environmental and human health, were targeted in this study. A site-specific conceptual site
model was constructed, based on effective, reasonable exposure pathways, to avoid any overestimation of the risk. Also, conservative
default values were adapted to prevent underestimation of the risk when site-specific values were not available. The risks
posed by the six contaminants were calculated using the API’s Decision Support System for Exposure and Risk Assessment, with
several assumptions. In the crater-formed-area (Ac), the non-carcinogenic risks (i.e., HI values) of tri-nitro-toluene (TNT)
and Cd were slightly larger than 1, but for RDX (Royal Demolition Explosives) was over 50. The total non-carcinogenic risk
of the whole gunnery range was calculated to be 62.5, which was a significantly high value. The carcinogenicity of Cd was
estimated to be about 10−3, while that for Pb was about 5 × 10−4, which greatly exceeded the generally acceptable carcinogenic risk level of 10−4–10−6. It was concluded from the risk assessment that there is an immediate need for remediation of both carcinogens and non-carcinogens
before construction of the reservoir. However, for a more accurate risk assessment, further specific estimations of the changes
in environmental conditions due to the construction of the reservoir will be required; and more over, the effects of the pollutants
to the ecosystem will also need to be evaluated. 相似文献