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301.
In this paper, we explore how scenarios of future water withdrawals in a river basin are influenced by scale-dependent quantifications of the driving forces for two global-scale storylines. Either global-scale information or region-specific information is used to do the quantifications. In addition, we analyze the impact of including or not some restricted regional-scale information in the employed water use model. To develop scenarios of water withdrawals in the German part of the Elbe River basin, we applied the modules for domestic, thermoelectric power and manufacturing water use of the global water model WaterGAP, using scale-dependent driving forces scenarios and other scale-dependent model input. In the global-scale quantitative interpretations of the storylines of the IPCC SRES scenarios A1 and B2, all major driving forces of water withdrawals in the basin—population, thermoelectric power production and industrial gross domestic product—show vigorous increases between 2000 and 2025, while from the regional perspective, smaller increases but mostly decreases appear to be plausible. These discrepancies are partly due to the fact that for the global-scale interpretations only the historic developments until 1990 were taken into account, and not until 2000 as in the regional case. The resulting scenarios of sectoral water withdrawals in 2025 differ strongly between the two scale-dependent interpretations of the storylines, with the global one leading to much higher absolute water withdrawals and much lower withdrawal decreases between 2000 and 2025. Therefore, for regional assessments of water withdrawals, we recommend to embed the scenario analysis in global-scale storylines by performing regional-scale quantifications of the global qualitative driving forces scenarios, based on a limited amount of region-specific information.  相似文献   
302.
Understanding the earth system requires that the two-way linkages between regions and the global system be well understood and predictable. Most studies of global change are undertaken thematically across limited disciplinary boundaries; few are attempted holistically across many disciplines within regions. The regional approach offers many advantages. Here a variety of linkages associated with the regions of Southern Africa, South Asia, East Asia and Southeast Asia are presented to illustrate the power of a regional approach to earth system science. Major findings include the extent to which long-range transport of aerosols and nutrients affect terrestrial and marine ecosystem functioning in and around southern Africa. Aerosol transport, and the development of a regional haze layer, over South Asia are shown to alter significantly the radiative forcing of change in the atmosphere over the region. Changes in land cover and use over East Asia over along period of time are shown to have affected the strength of the monsoon circulation significantly. Finally, rampant economic development and globalization in Southeast Asia are demonstrated to have been a significant driver of regional change. Electronic Publication  相似文献   
303.
Wet and dry deposition of polycyclic aromatic hydrocarbons (PAHs) was measured at Nahant, Massachusetts, a peninsula jutting into Massachusetts Bay and Wolf Neck, a peninsula jutting into Casco Bay, Maine. Wet deposition (rain and snow) was collected in a funnel which drains into a shielded, temperature controlled receiving bottle. Dry deposition of gaseous and particulate PAHs was collected onto an exposed water surface. PAHs were analyzed by solid phase extraction and gas chromatography-mass spectrometry. Sixteen PAH species were analyzed, ranging from acenaphthylene to coronene. The mean wet deposition rate of the sum of the 16 species is 720 ng m−2 cm−1 precipitation at Nahant, and 831 ng m−2 cm−1 precipitation at Wolf Neck. Wet deposition is attributed to regional PAH emitting sources. Storm patterns appear to bring somewhat higher wet deposition of PAHs to Wolf Neck than to Nahant. The mean dry deposition rate is 95 ng m−2 h−1 at Nahant and 9.3 ng m−2 h−1 at Wolf Neck. The large difference is attributed to the fact that Nahant is close to the urban-industrial metropolitan Boston area and Logan International Airport, whereas Wolf Neck has no major PAH-emitting sources nearby. Individual measurements have an error bracket of ±30%. The Chemical Mass Balance model was used to apportion the dry deposition to source categories. At Nahant, nine samples gave valid statistical attributes with a mean apportionment: jet exhaust 35%, gasoline fueled vehicles 32%, diesel fueled vehicles 17%, wood combustion 13%, others 3%. At Wolf Neck, six samples yielded a mean apportionment: jet exhaust 30%, gasoline vehicles 28%, diesel vehicles 18%, wood combustion 16%, others 8%. There is a considerable variation between the samples. The apportionment is greatly dependent on the quality and selection of the model inputs, i.e. source signatures, which for PAHs are questionable.  相似文献   
304.
Geochemical mapping is a technique rooted in mineral exploration but has now found worldwide application in studies of the urban environment. Such studies, involving multidisciplinary teams including geochemists, have to present their results in a way that nongeochemists can comprehend. A legislatively driven demand for urban geochemical data in connection with the need to identify contaminated land and subsequent health risk assessments has given rise to a greater worldwide interest in the urban geochemical environment. Herein, the aims and objectives of some urban studies are reviewed and commonly used terms such as baseline and background are defined. Geochemists need to better consider what is meant by the term urban. Whilst the unique make up of every city precludes a single recommended approach to a geochemical mapping strategy, more should be done to standardise the sampling and analytical methods. How (from a strategic and presentational point of view) and why we do geochemical mapping studies is discussed.
Christopher C. JohnsonEmail:
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305.
An assessment is presented of distribution characteristics of heavy metals in the urban topsoil from the city of Xuzhou. The concentrations of Ag, Al, As, Au, Ba, Be, Bi, Cd, Co, Cr, Cu, Fe, Ga, Hg, Li, Mn, Mo, Ni, Pb, Pd, Pt, Sb, Sc, Se, Sn, V and Zn have been determined from 21 soil samples. Examination of lognormal distribution plots indicates that the diagrams of Al, Be, Fe, Ga, Li, and V are almost linear suggesting that these metals are almost unaffected by anthropogenic activities while the plots for As, Cd, Cu, Pb, Pd, Pt, Se, Zn and others are not linear probably due to anthropogenic activities from which these metals are delivered to the soils. Al is used for mineralogical normalization of these data. An evaluation of background values for topsoil is also carried out by means of lognormal distribution plots. The results show our background values obtained from the lognormal distribution plots are comparable to those values of uncontaminated soils of Xuzhou obtained by previous work except for Cd and Hg. At present, no explanation for the exceptions Cd and Hg can be given.  相似文献   
306.
本文依据区域发展战略环境影响跟踪评价内涵,结合我国实践需要,阐明区域发展战略环境影响跟踪评价技术路线和内容,并进一步提出相关政策建议。研究指出,开展区域发展战略环境影响跟踪评价应坚持基于生态环境需求优先的技术路线、提高跟踪评价的战略性和开展战略环境影响跟踪评价试点。  相似文献   
307.
结合电磁辐射类项目特点及难点,阐述公众参与的环境知情权、环境参与权和环境司法请求权3原则。围绕原则梳理公众关心的主要问题,制订出信息公示内容及公众参与方案,并对公众参与制度提出合理建议,对开展移动通信基站项目公众参与具有理论指导和现实意义  相似文献   
308.
Emissions from mobile sources and stationary sources contribute to atmospheric pollution in China, and its components, which include ultrafine particles (UFPs), volatile organic compounds (VOCs), and other reactive gases, such as NH3 and NOx, are the most harmful to human health. China has released various regulations and standards to address pollution from mobile and stationary sources. Thus, it is urgent to develop online monitoring technology for atmospheric pollution source emissions. This study provides an overview of the main progress in mobile and stationary source monitoring technology in China and describes the comprehensive application of some typical instruments in vital areas in recent years. These instruments have been applied to monitor emissions from motor vehicles, ships, airports, the chemical industry, and electric power generation. Not only has the level of atmospheric environment monitoring technology and equipment been improving, but relevant regulations and standards have also been constantly updated. Meanwhile, the developed instruments can provide scientific assistance for the successful implementation of regulations. According to the potential problem areas in atmospheric pollution in China, some research hotspots and future trends of atmospheric online monitoring technology are summarized. Furthermore, more advanced atmospheric online monitoring technology will contribute to a comprehensive understanding of atmospheric pollution and improve environmental monitoring capacity.  相似文献   
309.
The incineration of sacrificial offerings is a significant widely practiced custom that is also a kind of neglected air pollution source in China. Our results showed that the emission factors of particulate matter, SO2, CO, NOx, and VOCs emitted from the incineration of sacrificial offerings with purification systems were reduced by 95%, 19%, 9%, 82%, and 42%, respectively, compared with those without a purification system, revealing a significant effect of the flue gas purification system on reducing particulate matter and gaseous pollutants. The emission level of air pollutants from the incineration of sacrificial offerings remained stable before 2013 and then showed a remarkable decrease after the implementation of China´s Air Pollution Prevention Action Plan in 2013. The emissions of TSP (total suspended particulate), PM10, PM2.5, and NOx in 2009 were 8222, 6106, 5656 and 15,878 ton, respectively, obviously higher than 3434, 2551, 2305 and 8579 ton in 2019. Such trend was affected by both the quantity of incineration and the installation rate of purification systems after the Emission Standard of Air Pollutants for Crematory (GB 13801-2015) issued in China. Distinct spatial distribution of atmospheric pollutants from incineration of sacrificial offerings was found with higher in the east and south of China than the west and north of China, which is proportional to the regional economy and population. The maximum ground-level concentration typically occurred at 0.12-0.2 km from the pollution source, posing potential health risks to people entering and exiting funeral and burial sites and nearby residents.  相似文献   
310.
As a policy instrument for sustainable development, nationwide circular economy (CE) mode has been implemented for 7 years by the Chinese government, to overcome the dilemma among economic depression, energy shortage and environmental pollution. Unfortunately, few literatures contribute to checking the efficiency of regional CE and exploring the potential reasons in China, which will be practically helpful in guiding China's future development and providing reference for other developing countries that will adopt CE mode. Therefore, this paper puts forward the method of super-efficiency DEA window analysis to dynamically evaluate CE efficiency of 30 regions in China covering the period of 2005–2010. In line with the features of CE, the specific efficiency of three sub-systems, namely resource saving and pollutant reducing (RSPR) sub-system, waste reusing and resource recycling (WRRR) sub-system and pollution controlling and waste disposing (PCWD) sub-system, was assessed and compared regarding time series trend and spatial distribution, based on which, the comprehensive CE efficiency was totally ranked. The results show that, on the one hand, during the period of 2005–2010, Chinese CE efficiency slightly increased, implying a significant policy effect of CE; on the other hand, the efficiency of different sub-systems varies, with RSPR sub-system the lowest, and WRRR and PCWD sub-systems relatively higher. In terms of regional distribution, the efficiency of RSPR sub-system in the east area dominates during the whole period. However, for the other two sub-systems, from 2005 to 2007, the efficiency scores of the east fluctuate, then after 2007, the east area became more efficient than the central and the west areas. Throughout the study period, the RSPR sub-system in the central area stably maintains low efficiency, and so does the WRRR sub-system in the west area. The difference in regional efficiency of three sub-systems reflects the difficulty of carrying out CE policy in China comprehensively, which means that, promoting the adaptability of regional policy for local government and enhancing the coordination among various policies for China's central government are the key concerns for realizing sustainable development.  相似文献   
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