全文获取类型
收费全文 | 322篇 |
免费 | 2篇 |
国内免费 | 4篇 |
专业分类
安全科学 | 2篇 |
废物处理 | 4篇 |
环保管理 | 21篇 |
综合类 | 49篇 |
基础理论 | 164篇 |
环境理论 | 1篇 |
污染及防治 | 49篇 |
评价与监测 | 17篇 |
社会与环境 | 19篇 |
灾害及防治 | 2篇 |
出版年
2023年 | 23篇 |
2022年 | 28篇 |
2021年 | 15篇 |
2020年 | 2篇 |
2019年 | 18篇 |
2018年 | 17篇 |
2017年 | 15篇 |
2016年 | 12篇 |
2015年 | 9篇 |
2014年 | 14篇 |
2013年 | 23篇 |
2012年 | 21篇 |
2011年 | 17篇 |
2010年 | 20篇 |
2009年 | 12篇 |
2008年 | 16篇 |
2007年 | 12篇 |
2006年 | 7篇 |
2005年 | 7篇 |
2004年 | 4篇 |
2003年 | 7篇 |
2002年 | 7篇 |
2001年 | 3篇 |
2000年 | 1篇 |
1999年 | 5篇 |
1998年 | 5篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1992年 | 1篇 |
1988年 | 1篇 |
1958年 | 1篇 |
排序方式: 共有328条查询结果,搜索用时 31 毫秒
71.
In marine systems, the occurrence and implications of disturbance-recovery cycles have been revealed at the landscape level, but only in demographically open or closed systems where landscape-level dynamics are assumed to have no feedback effect on regional dynamics. We present a mussel metapopulation model to elucidate the role of landscape-level disturbance cycles for regional response of mussel populations to onshore productivity and larval transport. Landscape dynamics are generated through spatially explicit rules, and each landscape is connected to its neighbor through unidirectional larval dispersal. The role of landscape disturbance cycles in the regional system behavior is elucidated (1) in demographically open vs. demographically coupled systems, in relation to (2) onshore reproductive output and (3) the temporal scale of landscape disturbance dynamics. By controlling for spatial structure at the landscape and metapopulation levels, we first demonstrate the interaction between landscape and oceanographic connectivity. The temporal scale of disturbance cycles, as controlled by mussel colonization rate, plays a critical role in the regional behavior of the system. Indeed, fast disturbance cycles are responsible for regional synchrony in relation to onshore reproductive output. Slow disturbance cycles, however, lead to increased robustness to changes in productivity and to demographic coupling. These testable predictions indicate that the occurrence and temporal scale of local disturbance-recovery dynamics can drive large-scale variability in demographically open systems, and the response of metapopulations to changes in nearshore productivity. 相似文献
72.
Xinyou Mao Lan Wang Chuanyi Wang Eric Lichtfouse 《Environmental Chemistry Letters》2018,16(4):1429-1434
Minamata disease is caused by methylmercury, which is produced by microorganisms from inorganic mercury ions, Hg(II), in the aquatic environment. Adsorption is a feasible method to remove Hg(II) from waters, but there are some drawbacks when using conventional adsorbents, for example, tedious solid–liquid separation, slow response, and excessive residual levels of mercury. In this work, a novel spongy adsorbent has been developed for Hg(II) removal via surface functionalization of melamine formaldehyde sponge by glutathione. This material mimics a natural antidote that removes trace heavy metals in the human body. Results show that the functionalized sponge displays a 99.99% removal efficiency for low concentrations of Hg(II) of 10 mg/L. As a consequence, the residual Hg concentration is lower than 0.005 mg/L, which is slightly below the standard for total mercury in drinking water, of 0.006 mg/L, formulated by the World Health Organization, and much lower that the discharge regulation standard, of 0.01 mg/L, set by the ministry of environmental protection of China. Adsorption kinetic studies indicate that the functionalized sponge has a fast response. Indeed, the adsorption equilibrium can be reached within 10 min, and about 80% of total adsorption capacities are reached in 1 min. Moreover, the maximum adsorption capacity of the glutathione-functionalized sponge is as high as 240.02 mg/g, as shown by adsorption isotherm. Overall our findings disclose the great potential of the developed sponge adsorbent for rapid and efficient removal of Hg(II) from water. 相似文献
73.
Therville Clara Mathevet Raphaël Bioret Frédéric Antona Martine 《Regional Environmental Change》2018,18(2):607-618
Regional Environmental Change - On a global scale, protected areas (PAs) are one of the main tools used for biodiversity conservation. However, accelerated biodiversity loss and lack of social... 相似文献
74.
Francine Pratlong Pierre Boulot Eric Issert Martine Msika Frédéric Dupont Bruno Bachelard Pierre Sarda Jean-Louis Viala Daniel Jarry 《黑龙江环境通报》1994,14(3):191-198
One hundred and ninety women who contracted toxoplasmosis after the seventh week of pregnancy underwent antenatal diagnosis, including ultrasound examination and biological tests. Tests included Toxoplasma isolation in fetal blood and amniotic fluid by mouse inoculation, specific IgM and IgA in fetal blood, and non-specific tests. Twenty fetuses had positive specific as well as non-specific tests for Toxoplasma infection. At birth, four of these presented with clinical congenital toxoplasmosis and 12 with subclinical forms. Antenatal diagnosis enabled the detection of 83 per cent of the infected fetuses. Under specific conditions, cordocentesis permits early diagnosis and considerably reduces the number of terminations of pregnancy. 相似文献
75.
76.
We assessed the influence of environmental variables (elevation, stream order, distance from source, catchment area, slope, stream width, and fish species richness) on the co-occurrence patterns of the minnow, the stone loach, and the gudgeon at the stream system scale. A total of 474 sites were classified according to the seven variables using the Self-Organizing Map (neural network), and three clusters were detected (k-means algorithm). The frequency of the various fish co-occurrence patterns was calculated for each cluster, and general linear modeling was used to specify the conditions that predict the occurrence of each species. Piedmont streams were more likely to support coexisting gudgeon and minnow populations because of higher probabilities of occurrence for both species. The higher co-occurrence frequency for the three species together in headwater streams resulted from lower occurrence frequencies in gudgeon and minnow. Focusing on areas that favor the co-occurrence of species may enhance the effectiveness of conservation projects. 相似文献
77.
Eric Lichtfouse Valérie Sappin-Didier Laurence Denaix Giovanni Caria Laure Metzger Najat Amellal-Nassr Jens Schmidt 《Environmental Chemistry Letters》2005,3(3):140-144
We studied polycyclic aromatic hydrocarbons (PAHs) in crop soils amended with 1000 tonnes dry weight of sewage sludges per
10,000 m2 from 1974 to 1992, then after sludges addition from 1993 to 1999. The absence of variations of total PAHs levels of control
soils, averaging at 123 μg/Kg, shows the absence of horizontal contamination. During sludges addition, the total PAHs levels
in amended soils increased from 232 to 402 μg/Kg. Seven years after sludges addition, it decreased to 275 μg/Kg, which is
still more than twice –the levels of control soils. This finding shows that sludges PAHs are preserved in crop soils for long
periods of time, on a human scale. 相似文献
78.
Few studies have investigated the long-term fitness consequences of nestling size hierarchies in altricial birds. In this
study, we investigated whether or not the size rank order of siblings influences subsequent breeding success in the little
egret, Egretta garzetta. From a marking program allowing individual recognition of wild birds, we obtained data on the breeding success of 56 pairs
comprising individuals for which the size rank order was known. The breeding success in these pairs was positively influenced
by the age of the marked bird but negatively affected by the laying date of the pair and the size rank order of the marked
individual. There was also a significant difference between breeding colonies. We suggest two main hypotheses for a link between
size rank order of individuals and their breeding success and we discuss our results in relation to current hypotheses on
the adaptive value of hatching asynchrony.
Received: 10 August 1998 / Accepted after revision: 13 December 1998 相似文献
79.
Fossil fuel biomarkers, or "molecular fossils," are specific organic substances found in coals, petroleums, and sedimentary
rocks. They are formed during millions of years of sedimentary burial by geochemical alteration of biological molecules, such
as cholesterol, under the effect of biodegradation, temperature, pressure, and mineral catalysis, to produce geochemically
mature molecules, for example, aromatic steroids (Fig. 1). Since fossil fuel biomarkers have a very specific molecular structure
betraying fossil fuel sources, such markers should be useful in assessing the fossil fuel contamination of various modern
media such as soils, plants, waters, and modern sediments. Here the identification of fossil fuel biomarkers of high geothermal
maturity in sewage sludges provides evidence of the contamination of sludges by petroleum products. The most likely sources
of contamination are contaminated vegetal food, road dust, and soil particles carried by rain water.
Received: 18 January 1999 / Accepted in revised form: 19 May 1999 相似文献
80.
Adib Kfoury Frédéric Ledoux Cloé Roche Gilles Delmaire Gilles Roussel Dominique Courcot 《环境科学学报(英文版)》2016,28(2):114-128
The constrained weighted-non-negative matrix factorization(CW-NMF) hybrid receptor model was applied to study the influence of steelmaking activities on PM_(2.5)(particulate matter with equivalent aerodynamic diameter less than 2.5 μm) composition in Dunkerque,Northern France. Semi-diurnal PM_(2.5)samples were collected using a high volume sampler in winter 2010 and spring 2011 and were analyzed for trace metals, water-soluble ions, and total carbon using inductively coupled plasma – atomic emission spectrometry(ICP-AES),ICP- mass spectrometry(ICP-MS), ionic chromatography and micro elemental carbon analyzer. The elemental composition shows that NO_3~-, SO_4~(2-), NH_4~+and total carbon are the main PM_(2.5)constituents. Trace metals data were interpreted using concentration roses and both influences of integrated steelworks and electric steel plant were evidenced. The distinction between the two sources is made possible by the use Zn/Fe and Zn/Mn diagnostic ratios. Moreover Rb/Cr, Pb/Cr and Cu/Cd combination ratio are proposed to distinguish the ISW-sintering stack from the ISW-fugitive emissions. The a priori knowledge on the influencing source was introduced in the CW-NMF to guide the calculation. Eleven source profiles with various contributions were identified: 8 are characteristics of coastal urban background site profiles and 3 are related to the steelmaking activities. Between them,secondary nitrates, secondary sulfates and combustion profiles give the highest contributions and account for 93% of the PM_(2.5)concentration. The steelwork facilities contribute in about 2%of the total PM_(2.5)concentration and appear to be the main source of Cr, Cu, Fe, Mn, Zn. 相似文献