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891.
笔者从道路交通事故和景观方面 ,研究道路中央隔离设施的功能与特征。首先 ,利用对某城市道路中央有无隔离带情况下记录的交通事故数据 ,进行交通安全统计比较分析 ;其次 ,分别利用层次分析法和语言分级评价法 ,对城市道路中央双黄线、中央护栏隔离和中央绿化隔离 3种情况的景观进行分析 ;最后 ,通过综合分析给出分析结果 ,即中央绿化隔离、中央栅栏隔离带和双黄线隔离的评价顺序。 相似文献
892.
高校建筑规划与生态文明的思考 总被引:2,自引:0,他引:2
在规划和建筑设计中,实施生态文明,促进人与自然的协调和谐发展,正成为全球经济社会发展的新动向。加强高校校园环境保护,促进校园生态建筑文明,坚持可持续发展战略的理念,为师生员工提供一个优美、舒适、安静的工作和学习环境,使师生员享受到生态文明的乐趣。 相似文献
893.
Land-use planning using geographic information systems (GIS) commonly emphasizes biophysical spatial data; however planning
can be improved by integrating spatial sets of socioeconomic data into the GIS. As an example, we compared a traditional GIS-aided
forestry planning protocol that considered only biophysical suitability, with an integrated GIS-aided approach that incorporated
both biophysical and socioeconomic suitability. The analyses were conducted for the planning of plantation investments in
the Kyaukpadaung Township in the dry zone of central Myanmar. The traditional approach used three biophysical layers for suitability:
land use, slope, and accessibility. In contrast, the integrated GIS approach included biophysical suitability data, perceptions
and preferences of local villagers towards forestry (social suitability), and quantitative socioeconomic data. The results
indicated that the integrated approach provided two principal benefits over the traditional method. First, the integrated
method resulted in a more precise idea of suitable sites for plantation investment that could benefit more rural people and
also lead to greater investment efficiency. Second, incorporating social preference into the GIS takes into account the crucial
element of social capital (viz., social preference), which should lead to higher levels of community acceptance of plantation
projects because those plantations would be established on socially suitable land. A second GIS exercise showed how conservation
investment decisions could be informed using the integrated method. The results of this study support the idea that GIS-aided
planning activities can be enhanced through the incorporation of social data into the analysis. When applicable, spatial data
collection efforts for GIS-based planning exercises should incorporate spatial socioeconomic data. 相似文献
894.
本文针对如何正确处理开发旅游资源与保护景观的关系,运用景观生态学原理,阐述了景观生态协调机制的基本内容和实现这一机制的途径. 相似文献
895.
试论旅游经济与环境保护的关系——以香溪河风景线为例 总被引:5,自引:1,他引:4
阐述了旅游经济与环境保护矛盾的由来;分析了旅游经济系统,景观生态系统的结构与功能。指出旅游经济系统的旅游产品结构、旅游行业结构同环境保护关系最为密切,只有对其结构实行优化,才可能解决它们与景观生态系统结构之间的矛盾,把旅游经济活动对生态与环境影响降低到最小程度。旅游经济系统功能与景观生态系统功能,受其经济影响也经常处于矛盾状态之中。自然景观生态系统是通过食物链和食物网进行物质、能量传递的,倘若旅游 相似文献
896.
J.C. Doornkamp 《Journal of environmental management》1998,52(4):327-333
A review of the difficulties associated with the definition of coastal flood frequencies and magnitudes leads to a recognition that there is considerable doubt in many parts of the world as to the precise nature of this particular hazard. Similarly, a review of the sea-level measurements that have been used to indicate a response to global warming shows that there is uncertainty about the amount of other controlling influences. What is clear, however, are that past management decisions about human endeavours in the coastal zone (including flood defences, occupance of flood-prone lands, extraction of ground water and natural gas) have had an impact on relative land and sea levels and have done more to increase the risk of coastal flooding than can be assigned so far to global warming. In addition, these changes induced by human activity may render inappropriate calculations of coastal-flood frequencies based on historical records since the latter relate to a period of time when the controls on flooding may have been very different. 相似文献
897.
898.
中国80年代的国土规划实际上是50年代区域规划的继续和发展.在四川省编制各种不同的国土规划已近10年。本文以四川的区域(国土)规划实践为依据,就此在进入深化、提高阶段之后的问题.从规划组织形式、类型体系、研究方法的角度进行探讨。 相似文献
899.
D. P. Larsen N. S. Urquhart D. L. Kugler 《Journal of the American Water Resources Association》1995,31(1):117-140
ABSTRACT: The U.S. Environmental Protection Agency has proposed a sample survey design to answer questions about the ecological condition and trends in condition of U.S. ecological resources. To meet the objectives, the design relies on a probability sample of the resource population of interest (e.g., a random sample of lakes) each year on which measurements are made during an index period. Natural spatial and temporal variability and variability in the sampling process all affect the ability to describe the status of a population and the sensitivity for trend detection. We describe the important components of variance and estimate their magnitude for indicators of trophic condition of lakes to illustrate the process. We also describe models for trend detection and use them to demonstrate the sensitivity of the proposed design to detect trends. If the variance structure that develops during the probability surveys is like that synthesized from available databases and the literature, then the trends in common indicators of trophic condition of the specified magnitude should be detectable within about a decade for Secchi disk transparency (0.5–1 percentiyear) and total phosphorus (2–3 percent/year), but not for chlorophyll-a (> 3–4 percent/year), which will take longer. 相似文献
900.
Thomas S. Maddock Walter G. Hines 《Journal of the American Water Resources Association》1995,31(2):317-329
ABSTRACT: Most southwestern cities were founded along rivers or in areas having springs or readily available ground water. Because of the generally sparse precipitation, the renewable fresh water supply in the Southwest is smaller than most other areas of the United States. Despite the arid climate, water use has increased rapidly, first in the form of irrigation, and more recently the use in cities. This has caused extensive development of local water resources and overdraft of ground water basins in some areas. It is difficult to implement new local supplies and importation projects due to a myriad of environmental and legal constraints and a general shortage of public funds. Various opportunities and plans for water management, both on the demand and supply sides, are discussed. Evolving water strategies in four metropolitan areas - El Paso, Albuquerque, Las Vegas, and Phoenix - and issues regarding the Central Arizona Project are presented. 相似文献