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421.
The complexity of ecosystems urges that the evaluation process should avoid an aggregation of information. The reason is that although mathematical modelling has made enormous progress (object oriented programming) there is still no ecologically reasonable function of quality. The technique to compare chemicals for example, even if they are characterized by many properties, is based on the generalization of the concept of order and the method of visualization by the using Hasse diagrams. By the example of six chemicals the procedure will be explained and it will be shown that a high hazard potential of chemicals is related to different properties, which cause different ecotoxicological consequences. 相似文献
422.
Inorganic and carbonaceous components in indoor/outdoor particulate matter in two residential houses in Oslo, Norway 总被引:1,自引:0,他引:1
Lazaridis M Aleksandropoulou V Hanssen JE Dye C Eleftheriadis K Katsivela E 《Journal of the Air & Waste Management Association (1995)》2008,58(3):346-356
A detailed analysis of indoor/outdoor physicochemical aerosol properties has been performed. Aerosol measurements were taken at two dwellings, one in the city center and the other in the suburbs of the Oslo metropolitan area, during summer/fall and winter/spring periods of 2002-2003. In this paper, emphasis is placed on the chemical characteristics (water-soluble ions and carbonaceous components) of fine (PM2.5) and coarse (PM2.5-10) particles and their indoor/outdoor relationship. Results demonstrate that the carbonaceous species were dominant in all fractions of the PM10 particles (cut off size: 0.09-11.31 microm) during all measurement periods, except winter 2003, when increased concentrations of water-soluble inorganic ions were predominant because of sea salt transport. The concentration of organic carbon was higher in the fine and coarse PM10 fractions indoors, whereas elemental carbon was higher indoors only in the coarse fraction. In regards to the carbonaceous species, local traffic and secondary organic aerosol formation were, probably, the main sources outdoors, whereas indoors combustion activities such as preparation of food, burning of candles, and cigarette smoking were the main sources. In contrast, the concentrations of water-soluble inorganic ions were higher outdoors than indoors. The variability of water-soluble inorganic ion concentrations outdoors was related to changes in emissions from local anthropogenic sources, long-range transport of particles, sea salt emissions, and resuspension of roadside and soil dusts. In the indoor environment the infiltration of the outdoor air indoors was the major source of inorganic ions. 相似文献
423.
利用2006年南极威德尔海西北海域冬末春初的冰芯晶体结构,和302组冰芯温度、盐度、密度、叶绿素-a、脱镁叶绿素数据,以及冰底面叶绿素a垂直分布数据,进一步确定积雪/海冰厚度、冰内温度、盐度、密度对冰内和冰下叶绿素a的贡献.利用环境制约与生态平衡原理,阐明积雪/海冰厚度通过阻碍光通量对冰底叶绿素的效应,以及卤水体积通过冰温度和盐度体现对冰藻细胞活性的抑制作用.统计分析不仅确立了南极海冰冰内卤水体积-内叶绿素a的逻辑斯蒂上限含量曲线,并体现出粒状冰同柱状冰卤水排泄方式的差异及其对冰底春季叶绿素a快速增长的冰物理贡献.冰藻细胞活性指标小于0.5的仅占4.3%,该数据为南极冰藻是维持南极冰区浮游植物旺发的主导因子提供了重要依据. 相似文献
424.
Yuan Li Yanqun Zu Qixian Fang Zhaohua Gao Christian Schvartz 《Frontiers of Environmental Science & Engineering in China》2009,3(3):325-333
This paper studied the relationship between heavy metal concentrations of herbaceous plants and soils at four Pb-Zn mining
sites in Yunnan, China. 50 herbaceous plant samples of 9 plant species from 4 families and 50 soil samples were collected
and then ana1yzed for the tota1 concentrations of Pb, Cd, and Zn. The results showed that the average concentrations of Pb,
Cd, and Zn in soil samples were 3772.83, 168.81, and 5385.65 mg/kg, respectively. The average concentrations of Pb, Cd, and
Zn were 395.68, 28.14, and 1664.20 mg/kg in the shoots, and 924.12, 57.25, and 1778.75 mg/kg in the roots, respectively. Heterospecific
plants at the same site and conspecific plants at various sites had different average levels of Pb, Cd, and Zn, both in the
shoots and the roots. Enrichment coefficients of Pb, Cd, and Zn were greater than 1 in 2, 3, and 9 herbaceous plant samples,
respectively. Translocation factors of Pb, Cd, and Zn were greater than 1 in 10, 17, and 25 herbaceous plant samples, respectively.
In all 50 samples, the concentrations of Pb, Cd, and Zn between the shoots and the roots, the shoots, and the soils, and the
roots and the soils had significant positive relationships. 相似文献
425.
Tissue-specific congener composition of organohalogen and metabolite contaminants in East Greenland polar bears (Ursus maritimus) 总被引:1,自引:0,他引:1
Gebbink WA Sonne C Dietz R Kirkegaard M Riget FF Born EW Muir DC Letcher RJ 《Environmental pollution (Barking, Essex : 1987)》2008,152(3):621-629
Congener patterns of the major organohalogen contaminant classes of PCBs, PBDEs and their metabolites and/or by-products (OH-PCBs, MeSO2-PCBs, OH-PBDEs and MeO-PBDEs) were examined in adipose tissue, liver, brain and blood of East Greenland polar bears (Ursus maritimus). PCB, OH-PCB, MeSO2-PCB and PBDE congener patterns showed significant differences (p相似文献
426.
Response patterns in adult forest trees to chronic ozone stress: identification of variations and consistencies 总被引:1,自引:0,他引:1
Nunn AJ Reiter IM Häberle KH Langebartels C Bahnweg G Pretzsch H Sandermann H Matyssek R 《Environmental pollution (Barking, Essex : 1987)》2005,136(3):365-369
The responsiveness of adult beech and spruce trees to chronic O(3) stress was studied at a free-air O(3) exposure experiment in Freising/Germany. Over three growing seasons, gas exchange characteristics, biochemical parameters, macroscopic O(3) injury and the phenology of leaf organs were investigated, along with assessments of branch and stem growth as indications of tree performance. To assess response pattern to chronic O(3) stress in adult forest trees, we introduce a new evaluation approach, which provides a comprehensive, readily accomplishable overview across several tree-internal scaling levels, different canopy regions and growing seasons. This new approach, based on a three-grade colour coding, combines statistical analysis and the proficient ability of the "human eye" in pattern recognition. 相似文献
427.
David J. Marcogliese Christian Blaise Daniel Cyr Yves de Lafontaine Michel Fournier Fran?ois Gagné Christian Gagnon Christiane Hudon 《Ambio》2015,44(4):257-274
The St. Lawrence River (SLR) is the second largest waterway in North America. The discharge of the City of Montreal wastewater treatment plant (WWTP) represents the largest volume of treated wastewaters being released into the river. It also ranks as the largest sewage treatment plant of its kind in North America. Over the last decade, intensive multidisciplinary research has focused on assessing the impacts of Montreal wastewater effluents on the SLR. We describe the major findings of these investigations, including the determination of the fate of contaminants, bioaccumulation in fish and invertebrates, ecotoxicological measurements of aquatic animal health, evaluation of endocrine disruption, parasitism in fish, and combined effects of multiple stressors on the SLR. Impacts of the effluents from the WWTP on aquatic organisms from the SLR are both toxicological and ecological, demonstrating the need for an integrated view of the impacts of municipal effluents on aquatic ecosystems. 相似文献
428.
429.
Arctic marine mammal population status,sea ice habitat loss,and conservation recommendations for the 21st century
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Kristin L. Laidre Harry Stern Kit M. Kovacs Lloyd Lowry Sue E. Moore Eric V. Regehr Steven H. Ferguson Øystein Wiig Peter Boveng Robyn P. Angliss Erik W. Born Dennis Litovka Lori Quakenbush Christian Lydersen Dag Vongraven Fernando Ugarte 《Conservation biology》2015,29(3):724-737
Arctic marine mammals (AMMs) are icons of climate change, largely because of their close association with sea ice. However, neither a circumpolar assessment of AMM status nor a standardized metric of sea ice habitat change is available. We summarized available data on abundance and trend for each AMM species and recognized subpopulation. We also examined species diversity, the extent of human use, and temporal trends in sea ice habitat for 12 regions of the Arctic by calculating the dates of spring sea ice retreat and fall sea ice advance from satellite data (1979–2013). Estimates of AMM abundance varied greatly in quality, and few studies were long enough for trend analysis. Of the AMM subpopulations, 78% (61 of 78) are legally harvested for subsistence purposes. Changes in sea ice phenology have been profound. In all regions except the Bering Sea, the duration of the summer (i.e., reduced ice) period increased by 5–10 weeks and by >20 weeks in the Barents Sea between 1979 and 2013. In light of generally poor data, the importance of human use, and forecasted environmental changes in the 21st century, we recommend the following for effective AMM conservation: maintain and improve comanagement by local, federal, and international partners; recognize spatial and temporal variability in AMM subpopulation response to climate change; implement monitoring programs with clear goals; mitigate cumulative impacts of increased human activity; and recognize the limits of current protected species legislation. 相似文献
430.