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581.
冯琳  唐亮 《重庆环境科学》2001,23(6):13-15,27
在“控制导流,清污两制”的战略指导下,借助淮河入海水道的水工设施,利用南泓作为三淮一洪地区城市污水的调度通道和生态处理场所,尾水最终入海。研究表明,南泓生态工程净化能力显著,基本不会对沿线环境卫生、地下水、下游地面水及海口生态构成影响,是淮阴市三淮一洪以至下游滨海、阜宁地区未来污水安全可靠的出路。  相似文献   
582.
试论城乡开发自然生态补偿的植被还原原理   总被引:4,自引:0,他引:4  
针对城乡土地开发带来的植被破坏建立一种作为生态补偿的植被还原机制。本文列举国外的若干实例,说明在我国实行这一机制在技术和经济上的可行性。并提出植被还原的“绿当量”概念和针对开发项目造成的植被减少实行种植补偿的计算方法。  相似文献   
583.
生态城市建设的思路和实践   总被引:2,自引:0,他引:2  
从生态城市的概念,人类需求与生态完整性,空间尺度,结构与功能匹配,城市绿地,物种流6个方面介绍了生态城市设计和建设的基本思路。介绍了生态城市设计的技术方法。并以三亚城市生态规划为例介绍了生态城市建设的实践。生态城市是都市规划和建设和最佳模式,在总结系列实践工作的基础上,对生态城市建设做了理论和实践总结,以推动生态城市建设早日推广。  相似文献   
584.
西部开发中管道建设与生态环境保护的关系   总被引:2,自引:0,他引:2  
就西部开发中管道工程的建设,分析了管道工程的特点,管道工程对环境的影响因素,并根据西部生态环境的特点,阐述了该类项目生态环境的重要性,提出了生态环境保护的要点。  相似文献   
585.
广东省的生态足迹与可持续发展研究   总被引:21,自引:0,他引:21  
采用生态足迹模型对广东省2001年的生态足迹进行了实证计算和分析。结果表明:广东省生态足迹占用已远远超过其生态承载力,人均生态赤字为0.8198hm~2,总人口的生态赤字达6.20×10~7hm~2,表明广东生态系统的压力和强度甚高。造成广东高生态赤字的主要原因是:该省在快速的工业化和城市化进程中,高能源消耗及耕地资源流失量大。尽管广东可利用其经济优势,通过贸易来弥补部分的区域生态承载力不足,但由于当前大部分国家和地区人类对环境的影响已经超过了当地的生态承载力,因此从长远看,广东应主要考虑在不降低人们生活水平的前提下,减少生态足迹的需求,提高地区生态经济系统的发展能力。  相似文献   
586.
区域开发生态影响评价方法及应用   总被引:7,自引:0,他引:7  
建立一套系统的区域生态影响评价方法,对于区域环评和环境的可持续发展具有重要的意义。以济南舜湖社区区域开发为例,建立和应用由生态指标法、图形叠图法、景观生态学方法构成的方法体系,对舜湖社区区域开发生态环境影响进行了评价,并提出生态保护和建设的具体措施。结果表明,3者构成的方法体系,能较全面的反映生态环境质量现状,预测生态环境影响,有较为广泛的应用前景。  相似文献   
587.
In a long-term field manipulation, we demonstrate strong reactions of Leptothorax longispinosus ant colonies to food- and nest-site supplementation. Demographic and genetic responses varied over small geographic scales, and the two ecological factors interacted with the presence of the social parasite Protomognathus americanus. We conducted a 2×2 experiment in three blocks and found that the blocks, which were less than 100 m apart, reacted very differently to the treatments. Blocks differed in degree of polygyny, intranest relatedness, colony size, productivity, and sexual investment. Furthermore, these differences were associated with the presence of slave-making ants and the local availability of nest sites. Nest-site supplementation had a strong effect only in the site with the highest prevalence of social parasites, influencing there the density and investment patterns of colonies. L. longispinosus ants in the least parasitized area were strongly affected by both food- and nest-site supplementation. There, food supplementation led to a decrease in the number of queens per colony and consequently to an increase in intranest relatedness, while colonies in nest-site-supplemented areas invested fewer resources in males and produced a female-biased allocation ratio. By contrast, in a third block with a very low intracolonial relatedness, food supplementation induced an absolute and relative higher investment in males. We conclude that ecological factors influencing social organization in insect societies cannot be studied in isolation, because the interactions among factors produce far richer responses than any one variable.Communicated by L. Sundström  相似文献   
588.
The advertisement call of frogs and toads is an example of multiple message signal because different acoustic properties encode different kinds of biologically significant information. In the Italian treefrog, Hyla intermedia, pulse rate and frequency have been found to be under stabilizing female preferences and to encode information important for mate recognition, whereas the number of calls per call group have been found to be under directional preferences and, thus, to be important for mate quality assessment. In this study, we investigate preferences for calls that differ simultaneously in frequency, pulse rate, and number of calls per call group, and we ask how these properties interact with each other in influencing female mating decisions. Results of two-choice phonotaxis experiments provide no evidence to support the hypothesis that females process multi-attribute signals in a hierarchical way. In contrast, the pattern of preferences is consistent with the ‘preference function’ hypothesis, that is, with the hypothesis that females rank signals along an ordinal scale of values and choose accordingly. Pulse rate and frequency influence mating preferences more than does the number of calls per call group. The interaction between pulse rate and frequency is not additive but multiplicative: small differences in either pulse rate or frequency that, alone, have no effects on female choice, interact synergistically so that their combination has strong influence on female preferences. A preference repeatability test shows strong among-female differences in preference for multi-attribute signals. We suggest that this result reveals not only a variation in attribute values among females, but also a variation in the way females weight and combine attribute values into a single preference score.  相似文献   
589.
Biogeography of diseases: a framework for analysis   总被引:1,自引:0,他引:1  
A growing body of literature offers a framework for understanding geographic and ecological distributions of species; a few applications of this framework have treated disease transmission systems and their geography. The general framework focuses on interactions among abiotic requirements, biotic constraints, and dispersal abilities of species as determinants of distributional areas. Disease transmission systems have key differences from other sorts of biological phenomena: Interactions among species are particularly important, interactions may be stable or unstable, abiotic conditions may be relatively less important in shaping disease distributions, and dispersal abilities may be quite variable. The ways in which these differences may influence disease transmission geography are complex; I illustrate their effects by means of worked examples regarding West Nile Virus, plague, filoviruses, and yellow fever.  相似文献   
590.
Currently, the wastewater treatment plants (WWTPs) attempt to achieve the shifting from general pollution parameters control to reduction of organic micropollutants discharge. However, they have not been able to satisfy the increasing ecological safety needs. In this study, the removal of micropollutants was investigated, and the ecological safety was assessed for a local WWTP. Although the total concentration of 31 micropollutants detected was reduced by 83% using the traditional biological treatment processes, the results did not reflect chemicals that had poor removal efficiencies and low concentrations. Of the five categories of micropollutants, herbicides, insecticides, and bactericides were difficult to remove, pharmaceuticals and UV filters were effectively eliminated. The specific photosynthesis inhibition effect and non-specific bioluminescence inhibition effect from wastewater were detected and evaluated using hazardous concentration where 5% of aquatic organisms are affected. The photosynthesis inhibition effect from wastewater in the WWTP was negligible, even the untreated raw wastewater. However, the bioluminescence inhibition effect from wastewater which was defined as the priority biological effect, posed potential ecological risk. To decrease non-specific biological effects, especially of macromolecular dissolved organic matter, overall pollutant reduction strategy is necessary. Meanwhile, the ozonation process was used to further decrease the bioluminescence inhibition effects from the secondary effluent; ≥ 0.34 g O3/g DOC of ozone dose was recommended for micropollutants elimination control and ecological safety.  相似文献   
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