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381.
In this study critical load functions and target load functions of nitrogen and sulphur deposition with respect to acidity
and minimum base cation to aluminium ratio were calculated with the SAFE model using three different averaging strategies:
(1) averaging based on current forest generation, (2) averaging based on next generation and (3) averaging based on the entire
simulation period. From the results it is evident that although target load calculation and indeed critical load calculation
is straight forward, there is a problem in translating a predicted recovery according to the target load calculation back
to a site-specific condition. We conclude that a policy strategy for emission reductions that ensures recovery, according
to calculated target load functions, is likely to be beneficial from an ecosystem point of view. However, such a strategy
may not be sufficient to achieve actual non-violation of the chemical criteria throughout the seasonal or rotational variations.
To address this issue we propose a method for calculating dynamic critical loads which ensures that the chosen criteria is
not violated. 相似文献
382.
Jason Matus 《Disasters》2007,31(S1):S91-S103
Currently, the pace of recovery in the 'Three Areas' is moving faster than the implementation of the Comprehensive Peace Agreement (CPA). This gap is leading to greater imbalances in income, unsustainable urbanization, overexploitation of the environment and resource based conflict. Unless regulated, the likely result will be chronic poverty and an undermining of the success of the CPA. Agencies must be mindful of how they provide assistance so that they support the CPA. The analysis of food security should take place in the context of a larger political, social and economic analysis of the emerging situation. The least developed areas should be prioritised and interventions should provide benefits to the full range of socioeconomic groups. WFP must identify its role in the wider and integrated response. It should support the emerging peace process and the key reforms. If WFP chooses to consolidate its activities, it will require capable strategic partners. If it chooses to invest more in building the capacity of government and community structures, it must improve its skill base and field presence 相似文献
383.
Examining Hazard Mitigation Within the Context of Public Goods 总被引:1,自引:0,他引:1
Reddy SD 《Environmental management》2000,25(2):129-141
/ This paper presents a case study of an American barrier island devastated by a hurricane to show how it is addressing the free-riding problem and protecting its public goods, thereby contributing to hazard mitigation. It examines hazard mitigation and the free-riding problem within the public goods framework. Free-riding is a term used in the public choice theory and common pool resource literature. It is a term used for describing the actions of rational individuals who freely exploit a collective or public good at the expense of others. Free-riding is a major problem faced by public goods. The problem very frequently occurs in the context of hazard mitigation and coastal resource management. Very little is known about the factors that contribute to the promotion of hazard mitigation. This paper identifies some of the important factors that help local institutions provide and sustain hazard mitigation measures. Theoretical and practical implications for hazards research and disaster management policy are presented. 相似文献
384.
Edwin D. Bailey 《Journal of the American Water Resources Association》1979,15(3):801-811
ABSTRACT: The Tucson area is totally dependent on ground water, which is in increasingly short supply due to excessive overdrafts. Tucson area waste water treatment plants discharge material quantities of secondary effluent downstream, which is lost to evapotranspiration and recharge of the ground water basin. The city and the four large mining companies who share the common Santa Cruz basin ground water, recognized the common water supply problem and agreed to fund a feasibility study for mining process use of the effluent to partly alleviate the overdraft of ground water. The study analyzed the projected waste water effluent resources, potential mining company demand for waste water effluent and possible interface of an effluent delivery facility with the proposed Central Arizona Project. The effluent resources were analyzed with respect to potential demand. An optimum alignment was selected. An optimum system was detailed through design schematics, amortized cost and finance requirements, and an implementation schedule. It was concluded that a waste water effluent delivery facility could be implemented which would utilize reclaimed effluent in quantities approximating 35 percent of basin overdraft and which would provide revenue for full cost recovery over a 20 year operation period. The mining companies are studying the internal economic impacts of the project. 相似文献
385.
The idea of pre-impact recovery planning has recently been promoted by researchers and practitioners, but very little research has been done to evaluate its effects on disaster recovery. This study compared two jurisdictions — the city of Los Angeles, California and Taichung county in Taiwan — in their recovery from earthquakes. Although the two cases also differ with respect to variables other than the presence of pre-impact recovery plans, the available data suggest that having a pre-impact recovery plan facilitates housing reconstruction and allows local officials to make more effective use of the window of opportunity after disaster to integrate hazard mitigation into the recovery process. 相似文献
386.
387.
388.
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
389.
390.
研究了Cu2+、Cd2+、Ni2+对2-氯酚(2-CP)厌氧降解及其微生态结构的影响.结果表明,重金属冲击对连续流厌氧系统具有明显的抑制作用,抑制程度为Cu2+>Ni2+>Cd2+;300mg/L重金属冲击使系统降解率低于30%,需驯化40d左右才能恢复,其中受Ni冲击的体系恢复较快;不同浓度金属离子对2-CP间歇降解系统的抑制作用同样为Cu2+>Niv2+>Cd2+;低浓度重金属离子的驯化能提高污泥对重金属的抗性,驯化后300mg/Lcu2+和Ni2+对降解速率的抑制均降低了45%左右.重金属对厌氧体系的抑制作用和对厌氧污泥微生态结构的影响之间具有很大相关性,厌氧微生态结构受Cu2+冲击后影响最大,受Ni2+影响后恢复最快. 相似文献