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691.
宁东能源化工基地规划产业布局的生态适宜性分析   总被引:3,自引:0,他引:3  
基于遥感和地理信息系统技术,在宁东地区土壤侵蚀敏感性评价的基础上,对宁东能源化工基地规划的产业布局进行了生态适宜性分析.结果表明,宁东能源化工基地规划的煤炭、电力和煤化工三大主导产业布 局与该区生态环境不相适宜.在规划的12座煤矿、7个电厂和3个煤化工园区中,有3座煤矿、2个电厂和1个化工园区位于土壤侵蚀的高度敏感区内;有2座煤矿、3个电厂和1个化工园区位于土壤侵蚀的中度敏感区内.为更好的促进区域生态环境与经济社会的协调发展,探索性地提出了宁东能源化工基地产业布局规划的优化调整建议.  相似文献   
692.
Sustainability can only be assured with a human-ecological understanding of the complexinteractions among environmental,economic and social/cultural factors and with careful planningand management grounded in ecological principles. This paper will probe an integrative methodologyfor achieving environmentally sound, economically productive, and ecologically responsibledevelopment in urban and industrial areas of China through ecological regulation. The central objec-tive is to promote highly efficient resource use rather than high speed development,harmonious sys-tem′s relationship rather than inflexible compartmentalization, and robust and vital self-organizationrather than bureaucrstic control. This ecological order is to be regulated through technological inno-vation,institutional reform, and behavioral incentives that promote positive economic dcvelopmentwhile mitigating negative environmental impacts.  相似文献   
693.
基于景观生态学的天目湖湿地公园规划   总被引:1,自引:0,他引:1  
通过野外调查和利用1∶1000、1∶10000地形图作GIS判读分析,以景观生态学原理为指导,对天目湖湿地公园进行规划。在将天目湖湿地划分成平坦开阔区、岛山、浅冲和廊道4类斑块基础上,以保护和利用湿地资源,发挥廊道的生态功能,突出绿斑、蓝带、开敞空间的整合为规划控制思路,对规划出的水生花卉园、湖滨生态园、平桥河生态廊道、芦苇园、林岛园、"双龙"入湖生态景观带以及生态产业和生态人居园7类用地布局作了描述。  相似文献   
694.
对环境灾害的概念、特点、类型及主要研究内容进行了初步探讨。  相似文献   
695.
The efficacy of simultaneously advancing two distinct conceptual designs (referred to here as fixed-site and non-fixed-site) for species conservation and protection is addressed. In the literature, numerous models can be found that typically stem from a particular design, but rarely are comparisons made between approaches. This paper presents a more integrated optimization framework that models landowner behavior and species viabilities at a landscape scale. Regional demand for resource extraction is used as the economic driver, a variant of simulated annealing is used to solve the model under different species protection approaches, and a detailed species population simulator is utilized to measure biological responses. When directly comparing the outcomes of different species protection strategies from a case study in Oregon (USA), it was found that neither approach was universally superior in terms of financial value or degree of protection for two late seral forest dependent species.  相似文献   
696.
Natural capital in ecology and economics: an overview   总被引:2,自引:0,他引:2  
The Brundtland Commission report, Our Common Future, defined sustainable development as development that meets the needs of the present without compromising the ability of futuregenerations to meet their own needs. Although the idea of sustainable development has been widely accepted, it has proveddifficult to identify and implement policies and practices thatpromote sustainable economic growth. Some economists, environmental scientists and policy analysts believe that they can transform the consensus about sustainability into manageablepractices. They propose to accomplish this feat with a set of new ideas about the relationships between the economy and theenvironment offered under the banner of 'natural capital'. An ideal account of natural capital would be one or more standard measures or models that would allow the direct comparison of environmental goods, like forests, fresh water and clean air, with economic goods, like money, capital and productivity. By bringing economic science and environmental science to an objective common ground, a natural capital model has the potentialto provide a concrete means of comparing the economic and ecological costs and benefits of particular policies and programmes. This paper offers a survey and analysis of several new contributions to the formation of the natural capital concept from economists, ecologists, policy analysts, biometricians, foresters and a philosopher. The paper concludes that existingmicroeconomic theory may be 'ungreenable', if it is not reformulated. While macroeconomic approaches to natural capitalhave been more successful, they share the limitation that ecosystems and species are valued solely in monetary terms. These problems are taken to suggest that the development of a successful natural capital model may require economic theory tobe recast to include non-monetary social preferences and values.  相似文献   
697.
Natural capital models attempt to remediate the relationship between economics and ecology either by conjoining models and theories from each discipline or by finding a type of phenomena that can be meaningfully measured by both fields. The developmentof a widely accepted model which integrates economics and ecologyhas eluded researchers since the early 1970s. This paper offers an historical and philosophical perspective on some of the conceptual problems or obstacles that hinder the development ofnatural capital models. In particular, the disciplinary assumptions of economic science and ecological science are examined and it is argued that these assumptions are antithetical. Hence, the development of an effective and acceptednatural capital model will require that economics and ecology reconsider their self-conceptions as sciences. For the purposesof theoretical research and practical policy, the paper cautionsagainst confusing the issue of whether or not economic models accord with ecological models with the issue of whether or not economic activities accord with ecological realities.  相似文献   
698.
目的建立实验室降雪环境模拟技术,为飞机等武器装备降雪环境适应性试验验证提供技术支持。方法基于对自然降雪和实验室模拟降雪机理的对比与分析,提出影响实验室内模拟降雪的关键因素,并结合理论分析和试验研究,得出实验室内模拟降雪环境的冷负荷计算方法和最优成雪的水粒直径。结果建立了实验室降雪环境模拟技术,采用该降雪环境模拟技术,降雪强度及降雪品质均满足飞机等武器装备降雪环境适应性试验验证需求。结论建立的降雪环境模拟技术切实有效,可用于实验室飞机等武器装备降雪环境适应性试验研究。  相似文献   
699.
汽车环境风洞设计概述   总被引:2,自引:2,他引:0       下载免费PDF全文
为了模拟真实的自然环境进行整车试验,汽车环境风洞是必不可少的试验手段。简述了汽车环境风洞的整体设计概念,并对最重要的空气动力学和环境模拟系统的设计进行了较为细致的论述。风洞流道不同部件均有独特的作用,各个部件的协同设计会带来优秀的空气动力学性能。环境模拟系统的设计考虑到了风洞设备和实验的热负荷,以及风洞升降温速率的要求,保证制冷能力能够满足汽车环境实验工况的要求,并且配备了道路、阳光、雨雪等自然环境的模拟设备。环境风洞不同部件发挥各自的功能,可以带来优秀的空气动力学和热力学能力。通过多方面的综合设计,汽车环境风洞可以非常好地模拟自然的环境条件,进而进行整车实验。  相似文献   
700.
Lake Superior receives inputs from approximately 2,800 tributaries that provide nutrients and dissolved organic matter (DOM) to the nearshore zone of this oligotrophic lake. Here, we review the magnitude and timing of tributary export and plume formation in Lake Superior, how these patterns and interactions may shift with global change, and how emerging technologies can be used to better characterize tributary–lake linkages. Peak tributary export occurs during snowmelt‐driven spring freshets, with additional pulses during rain‐driven storms. Instream processing and transformation of nitrogen, phosphorus, and dissolved organic carbon (DOC) can be rapid but varies seasonally in magnitude. Tributary plumes with elevated DOC concentration, higher turbidity, and distinct DOM character can be detected in the nearshore during times of high runoff, but plumes can be quickly transported and diluted by in‐lake currents and mixing. Understanding the variability in size and load of these tributary plumes, how they are transported within the lake, and how long they persist may be best addressed with environmental sensors and remote sensing using autonomous and unmanned vehicles. The connections between Lake Superior and its tributaries are vulnerable to climate change, and understanding and predicting future changes to these valuable freshwater resources will require a nuanced and detailed consideration of tributary inputs and interactions in time and space.  相似文献   
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