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101.
McCarthy K 《Environmental monitoring and assessment》2006,118(1-3):293-318
Semipermeable membrane devices (SPMDs) were deployed at eight sites within the Buffalo Slough, near Portland, Oregon, to (1)
measure the spatial and seasonal distribution of dissolved polycyclic aromatic hydrocarbon (PAH) and organochlorine (OC) compounds
in the slough, (2) assess the usefulness of SPMDs as a tool for investigating and monitoring hydrophobic compounds throughout
the Columbia Slough system, and (3) evaluate the utility of SPMDs as a tool for measuring the long-term effects of watershed
improvement activities. Data from the SPMDs revealed clear spatial and seasonal differences in water quality within the slough
and indicate that for hydrophobic compounds, this time-integrated passive-sampling technique is a useful tool for long-term
watershed monitoring. In addition, the data suggest that a spiking rate of 2–5 μg/SPMD of permeability/performance reference compounds, including at least one compound that is not susceptible to photodegradation,
may be optimum for the conditions encountered here. 相似文献
102.
张乐才 《中国人口.资源与环境》2011,21(2)
文章用污染要素的替代效应与成本效应对污染集聚的形成机理进行了分析,研究结果说明污染红利会带来污染集聚.首先,污染替代效应会导致污染密集型产业成为主导产业;其次,污染成本效应一方面会导致单个企业排污加大,另一方面还会扩大污染密集型企业的数量;第三,污染替代效应和成本效应作为污染总效应的分支,二者的作用是累加的,不会互相抵消.为了检验该研究结论的正确性,本文用内蒙古工业规模效应、工业结构效应、工业科技效应指标对该省废气排放总量进行了回归分析,结果支持了上述研究结论.首先,有利于把污染当作红利使用的工业规模效应与工业科技效应均促进了废气排放的增加;其次,抑制把污染当作红利使用的工业结构效应则促进了废气排放的减少.因此,我国彻底治理环境污染是一项长期的任务,我们在加大产业结构调整的过程中,尤应加大对污染密集型产业的抑制. 相似文献
103.
治理校园安全事件的长效对策 总被引:2,自引:0,他引:2
任国友 《中国安全生产科学技术》2010,6(4):33-38
当前,我国校园安全总的形势比较严峻,特别是2010年3月以来不到40天的时间内发生了5起校园公共突发事件。为了及时、客观地把握校园安全的基本现状,笔者运用网络调查与文献研究的方法,统计分析了自1997年以来国内外典型校园安全事件。调研结果表明,国内外校园安全形势基本态势趋紧,以美国为代表的国外发达国家校园枪击案较为典型,其根源是枪支文化和强者文化;当前,国内校园案件呈上升趋势,但随着各项综合治理措施的跟进,总体情况趋于平稳,呈现"内忧外患"基本特征,既有突出的内部原因,也有外部因素的协同作用,其中缺少校园安全综合治理的长效机制是主因。校园安全涉及的因素较多,本文从法制环境、治理机制、管理体制三个方面提出了建立校园安全长效机制的具体对策与建议。 相似文献
104.
105.
Environmental Vulnerability Indicators for Environmental Planning and Decision-Making: Guidelines and Applications 总被引:6,自引:0,他引:6
Environmental decision-making and policy-making at all levels refers necessarily to synthetic, approximate quantification
of environmental properties such as vulnerability, conservation status, and ability to recover after perturbation. Knowledge
of such properties is essential to informed decision-making, but their definition is controversial and their precise characterization
requires investments in research, modeling, and data collection that are only possible in the most developed countries. Environmental
agencies and governments worldwide have increasingly requested numerical quantification or semiquantitative ranking of such
attributes at the ecosystem, landscape, and country level. We do not have a theory to guide their calculation, in general
or specific contexts, particularly with the amount of resources usually available in such cases. As a result, these measures
are often calculated with little scientific justification and high subjectivity, and such doubtful approximations are used
for critical decision-making. This problem applies particularly to countries with weak economies, such as small island states,
where the most precious environmental resources are often concentrated.
This paper discusses frameworks for a “least disappointing,” approximate quantification of environmental vulnerability. After
a review of recent research and recent attempts to quantify environmental vulnerability, we discuss models and theoretical
frameworks for obtaining an approximate, standardizable vulnerability indicator of minimal subjectivity and maximum generality.
We also discuss issues of empirical testing and comparability between indicators developed for different environments. To
assess the state of the art, we describe an independent ongoing project developed in the South Pacific area and aimed to the
comparative evaluation of the vulnerability of arbitrary countries. 相似文献
106.
Ecological Compensation in Dutch Highway Planning 总被引:13,自引:0,他引:13
The ecological compensation principle was introduced by the Dutch government in 1993. This principle is designed to enhance
the input of nature conservation interests in decision-making on large-scale development projects and to counterbalance the
ecological impacts of such developments when implemented. This article evaluates the application of the Dutch compensation
principle in highway planning. Six current highway projects reveal consistent implementation of this principle, although provincial
policies on compensation and a national method for identifying compensation measures are still under development. As the planning
process has not yet been completed for all the projects, no general conclusions can be drawn on the impact of the compensation
principle on highway decision-making. Nevertheless, several examples show that the principle stimulates project initiators
to develop alternative routes or route sections in order to avoid or reduce ecological impacts and the need for coherent compensation
measures. If the compensation principle is to be properly implemented in the context of highway planning, particular attention
should be paid to the following aspects: (1) sequential assessment of overall project legitimacy and the necessity of intersecting
protected areas and compensation measures, (2) the initiator's attempts to avoid and mitigate ecological impacts in developing
alternative routes prior to compensation for impacts, and (3) the role of uncertain ecological impacts in identifying compensation
measures, especially those concerning habitat isolation. 相似文献
107.
研究了5%锐颈特县浮剂与95%马拉硫磷文替使用对麦穗鱼(Pseudorasbora paroa)乙酰胆碱酯酶(AChE,EC3.1.1.7)活性的影响。结果表明,0.2mg/L,锐颈物与2mg/L马拉硫磷交替使用均影响被抑制的AChE活性恢复。文中还探讨了研究农药影响对于合理评价农药环境毒性的意义。 相似文献
108.
长期定位施肥田土壤酶活性的动态变化特征 总被引:30,自引:0,他引:30
为探讨长期施肥条件下玉米生育期内土壤酶活性的动态变化及其与土壤肥力的关系,该文对北京褐潮土定位试验田第12年的土壤酶以及土壤养分因子进行了测定和分析.结果表明.土壤过氧化氢酶、磷酸酶在玉米拔节期出现活性高峰.土壤脲酶在玉米拔节期及成熟期出现两个活性高峰,土壤蔗糖酶在整个玉米生育期内活性变化幅度较小.长期施肥能明显提高土壤中蔗糖酶、脲酶、磷酸酶活性,其中有机肥与化肥配施对于增加土壤中蔗糖酶、脲酶、磷酸酶活性尤为显著.长期施肥降低土壤中过氧化氢酶活性.并且以NPK配施有机肥处理的土壤过氧化氢酶活性降低幅度最大.土壤酶之问及其与土壤养分因子之间具有明显相关性,其中蔗糖酶、脲酶及磷酸酶与土壤养分各因子均呈显著或极显著正相关,除碱解氮外,过氧化氢酶与其余各养分因子呈显著或极显著负相关. 相似文献
109.
Observed levels and trends of gaseous SO2 and HNO3 at Mt. Waliguan, China: Results from 1997 to 2009
Long-term measurements of SO2 and HNO3,particularly those from the background sites,are rarely reported.We present for the first time the long-term measurements of SO2 and HNO3 at Waliguan(WLG),the only global baseline station in the back-land of the Eurasian Continent.The concentrations of SO2 and HNO3 were observed at WLG from 1997 to 2009.The observed annual mean concentrations of SO2 and HNO3 at WLG were 1.28±0.41 and 0.22±0.19μg/m3,respectively.The HNO3 concentrations were much higher in warmer seasons than in colder seasons,while the SO2 concentrations showed a nearly reversed seasonal pattern.In most months,the concentration of HNO3 was significantly correlated with that of SO2,suggesting that some common factors influence the variations of both gases and the precursors of HNO3 may partially be from the SO2-emitting sources.The SO2 concentration had a very significant(P < 0.0001) decreasing trend(-0.2μg/(m3·yr)) in 1997-2002,but a significant(P < 0.05) increasing trend(+0.06 μg/(m 3 ·yr)) in 2003-2009.The HNO3 concentration showed no statistically significant trend during 1997-2009.While the decrease of SO2 in 1997-2002 agrees with the trend of global SO2 emissions,the increase in 2003-2009 is not consistent with the decreasing trends in many other regions over the world.Trajectory analysis suggests that the airmasses from the northern Qinghai-Tibetan Plateau and the Takla Makan Desert regions contributed significantly to the increasing trends of SO2 and HNO3 at WLG in 2003-2009,with a rate of +0.13μg/(m3·yr) and +0.007μg/(m3·yr),respectively. 相似文献
110.
赵朔 《辽宁城乡环境科技》2013,(9):69-71
构建长效机制保护农村环境,是一项庞大而复杂的系统工程,强有力的推进措施是实施这一工程的重要保证。结合农村环境实际状况及环保工作实践,提出推进措施的关键是宣传到位形成共识,问责到住形成合力,投入到位形成平台。并进一步提出宣传的重点是要持续提升农村居民的环保意识,持续凝结农村各界的环保行动共识;问责的重点是要加强政府规划引领,分解落实可考核责任;投入的重点是要多渠道增加经费供给,克服农村环保资金瓶颈;提高科技支撑力度,以科技促环保: 相似文献