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地震次生火灾动态危险性分析方法研究 总被引:7,自引:2,他引:5
提出了一个城市地震次生火灾动态危险性分析与预估的一般模型。根据地震次生火灾发生具有离散性和随机性的特点,采用泊松过程模型作为地震次生火灾发生的初始估计模型。在此基础上,按照时、场域分离的原则和贝叶斯估计原理,发展了地震次生火灾动态危险性分析与模型,建议了动态危险性分析方法,经实例验证,本文所建议的模型与方法是合理可信的。 相似文献
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公路隧道事故预防分析 总被引:1,自引:0,他引:1
探讨了公路隧道交通事故的特点和主要影响因素,采用事故树分析法对可能导致隧道火灾事故的因素进行了分析,得出在隧道内减少可燃烧物品数量和采用阻燃或不燃物品做内装饰是降低隧道火灾发生概率的有效措施,并提出了预防公路隧道交通事故和火灾的具体对策. 相似文献
605.
Phil Cottle 《Mitigation and Adaptation Strategies for Global Change》2007,12(1):181-201
The author uses his own data gleaned from over 10 years of commercial forestry insurance across the world to propose that
despite a low intrinsic fire risk across most of Southeast Asia, especially Indonesia, commercial fire losses are unacceptably
high, and could be reduced substantially within the current financial legal and political framework within which forestry
companies operate.
Opening with a statement about the dearth of forest fire loss data in the commercial sector, it is observed that the consequent
inability of general insurers to estimate the rate of fire loss leads to very low insurance participation in forestry within
Indonesia. A summary is then provided of the financial and environmental benefits of insurance participation in commercial
forestry were this situation to be changed.
A short discussion on risk perceptions is introduced to make the point that without reliable commercial forest fire loss data,
risk perceptions of fire exposure in Southeast Asia by the financial sector, including insurers, is a barrier to risk transfer
and investment. While real fire risk and perceived fire risk for Indonesia seem at present to be in agreement, the paper challenges
that this should the case.
Comparisons are made with different parts of the world with the knowledge that, in commercial terms, plantations in the low
latitudes behave similarly everywhere in terms of fire causes, fire propagation factors, and characteristics of plantation
or managed mixed forest fires. A review of the fire sizes within commercial forests is a good indicator of the efficiency
of fire management strategies, and profiles from a high fire risk territory and Indonesia are compared.
Using commercial and unidentified data the author then demonstrates that commercial growers in Indonesia have a high annual
rate of forest fire loss and may also have a significant catastrophe fire exposure. This ‘cat’ exposure is far greater than
for equivalent plantations in clearly higher fire risk environments. These conclusions are and should be discussed with forestry
companies to change attitude and investment levels.
Practical points for improved plantation fire management are made along with comments about the resources required. A parallel
discussion then reviews fire risk assessment and management by the insurers to prevent their own ‘forest fire’ losses if they
are to get further involved with the provision of Indonesian commercial forest risk transfer. The explanation of how insurers
price risk within a portfolio helps identify the specific data needed for a proper risk management strategy to be developed. 相似文献
606.
LARS A. BRUDVIG§ CATHERINE M. MABRY JAMES R. MILLER† TRACY A. WALKER‡ 《Conservation biology》2007,21(3):864-874
Abstract: Reintroduction of fire and grazing, alone or in combination, has increasingly been recognized as central to the restoration of North American mixed-grass and tallgrass prairies. Although ecological studies of these systems are abundant, they have generally been observational, or if experimental, have focused on plant species diversity. Species diversity measures alone are not sufficient to inform management, which often has goals associated with life-form groups and individual species. We examined the effects of prescribed fire, light cattle grazing, and a combination of fire and grazing on three vegetation components: species diversity, groups of species categorized by life-form, and individual species. We evaluated how successful these three treatments were in achieving specific management goals for prairies in the Iowa Loess Hills (U.S.A.). The grazing treatment promoted the greatest overall species richness, whereas grazing and burning and grazing treatments resulted in the lowest cover by woody species. Burning alone best achieved the management goals of increasing the cover and diversity of native species and reducing exotic forb and (predominantly exotic) cool-season grass cover. Species-specific responses to treatments appeared idiosyncratic (i.e., within each treatment there existed a set of species attaining their highest frequency) and nearly half of uncommon species were present in only one treatment. Because all management goals were not achieved by any one treatment, we conclude that management in this region may need refining. We suggest that a mosaic of burning and grazing (alone and in combination) may provide the greatest landscape-level species richness; however, this strategy would also likely promote the persistence of exotic species. Our results support the need to consider multiple measures, including species-specific responses, when planning and evaluating management . 相似文献
607.
火烧防火线在东北林区应用广泛,是预防森林火灾的重要措施.这项工作由于受天气、可燃物、点火技术等各方面因素影响较大,应用时具有一定的风险性.本文针对火烧防火线过程中,用火条件的选择、点火技术的运用以及用火安全等方面加以分析. 相似文献
608.
阐述了营造生物防火林带是阻隔林火蔓延、实现"绿色防火"的主要措施,对保障森林资源安全、减少森林灾害的损失将发挥积极作用. 相似文献
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