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21.
Zita Sebesvari Fabrice G. Renaud Susanne Haas Zachary Tessler Michael Hagenlocher Julia Kloos Sylvia Szabo Alejandro Tejedor Claudia Kuenzer 《Sustainability Science》2016,11(4):575-590
The sustainability of deltas worldwide is under threat due to the consequences of global environmental change (including climate change) and human interventions in deltaic landscapes. Understanding these systems is becoming increasingly important to assess threats to and opportunities for long-term sustainable development. Here, we propose a simplified, yet inclusive social–ecological system (SES)-centered risk and vulnerability framework and a list of indicators proven to be useful in past delta assessments. In total, 236 indicators were identified through a structured review of peer-reviewed literature performed for three globally relevant deltas—the Mekong, the Ganges–Brahmaputra–Meghna and the Amazon. These are meant to serve as a preliminary “library” of potential indicators to be used for future vulnerability assessments. Based on the reviewed studies, we identified disparities in the availability of indicators to populate some of the vulnerability domains of the proposed framework, as comprehensive social–ecological assessments were seldom implemented in the past. Even in assessments explicitly aiming to capture both the social and the ecological system, there were many more indicators for social susceptibility and coping/adaptive capacities as compared to those relevant for characterizing ecosystem susceptibility or robustness. Moreover, there is a lack of multi-hazard approaches accounting for the specific vulnerability profile of sub-delta areas. We advocate for more comprehensive, truly social–ecological assessments which respond to multi-hazard settings and recognize within-delta differences in vulnerability and risk. Such assessments could make use of the proposed framework and list of indicators as a starting point and amend it with new indicators that would allow capturing the complexity as well as the multi-hazard exposure in a typical delta SES. 相似文献
22.
沸石联合微生物固定化去除微污染水体中氨氮的研究 总被引:5,自引:0,他引:5
将沸石联合经过驯化的活性污泥微生物固定化,通过静态实验.考察了不同粒径沸石及不同组分固定化方法对沸石联合微生物固定化去除氨氮的影响;通过动态实验,考察了沸石联合微生物固定化去除微污染水体中低浓度氨氮的机制.结果表明,活性污泥经过16 d的驯化,氨氮去除率为90%以上;沸石吸附氨氮为快速吸附,粒径<0.5 mm的沸石的吸附容量明显大于其他粒径的沸石;不同组分固定化小球对氨氮的去除效率不同,各组分均有贡献,吸附容量依次为:沸石固定化小球>沸石联合微生物固定化小球>微生物固定化小球;沸石联合微生物固定化去除微污染水体中低浓度氨氮可分为4个阶段,即沸石吸附阶段、吸附饱和及微生物适应阶段、硝化作用明显加强和沸石部分再生阶段、微生物作用良好和沸石进一步再生阶段,最终沸石吸附与生物再生处于良好的动态平衡中,氨氮去除率达到60%左右. 相似文献
23.
Castello L Viana JP Watkins G Pinedo-Vasquez M Luzadis VA 《Environmental management》2009,43(2):197-209
Fishers and small-scale fisheries worldwide have been marginalized historically. Now it is clear that integrating fishers
in management processes is key to resource conservation, but it is less clear how to do it. Here, based on a literature review and new information, we present and analyze a case in which the participation
of fishers in the management process was crucial in recovering an overexploited small-scale fishery for the pirarucu (Arapaima spp.) in the Amazon Basin, Brazil. In 8 years of experimental management, from 1999 to 2006, the population of pirarucu increased
9-fold (from about 2200 to 20,650 individuals), harvest quotas increased 10-fold (from 120 to 1249 individuals), and fishers’
participation in the management process increased and they benefited from increased monetary returns. Additionally, the number
of communities conducting the management scheme increased from 4 in 1999 to 108 in 2006, following the demands of fishers
and regional government agencies. Based on our analysis, we suggest that the participation of fishers in the management of
other small-scale fisheries in the world can be improved by focusing on (1) applying the knowledge and skills of fishers in
resource monitoring and management, (2) bridging knowledge systems among all involved stakeholders, (3) collaborating with
fishers that are interested in, and capable of conducting, resource conservation schemes, and (4) conducting management under
conditions of uncertainty. 相似文献
24.
Hegetschweiler KT van Loon N Ryser A Rusterholz HP Baur B 《Environmental management》2009,43(2):299-310
Urban forests are popular recreation areas in Europe. Several of these temperate broad-leaved forests also have a high conservation
value due to sustainable management over many centuries. Recreational activities, particularly the use of fireplaces, can
cause extensive damage to soil, ground vegetation, shrubs, and trees. Firewood collection depletes woody debris, leading to
a loss of habitat for specialized organisms. We examined the effects of fireplace use on forest vegetation and the amount
of woody debris by comparing disturbed and control plots in suburban forests in northwestern Switzerland. At frequently used
fireplaces, we found reduced species densities in the ground vegetation and shrub layer and changes in plant species composition
due to human trampling within an area of 150–200 m2. Picnicking and grilling also reduced the height and changed the age structure of shrubs and young trees. The amount of woody
debris was lower in disturbed plots than in control plots. Pieces of wood with a diameter of 0.6–7.6 cm were preferentially
collected by fireplace users. The reduction in woody debris volume extended up to a distance of 16 m from the fire ring, covering
an area of 800 m2 at each picnic site. In order to preserve the ecological integrity of urban forests and to maintain their attractiveness
as important recreation areas, we suggest depositing logging residues to be used as firewood and to restrict visitor movements
near picnic sites. 相似文献
25.
Agri-environment programs aim to secure environmental and social stewardship services through payments to farmers. A critical
component of many agri-environment programs is an agri-environment index (AEI) used to quantify benefits and target investments.
An AEI will typically comprise multiple indicators, which are weighted and combined using a utility function, to measure the
benefit of investment options (e.g., projects, farms, regions). This article presents a review of AEIs with 11 case studies
from agri-environment programs in the United States, Australia, and the United Kingdom. We identify a generic procedure used
to define AEIs and explore the implications of alternative methodological approaches. We conclude that AEIs have become an
extremely important policy instrument and make suggestions for their improvement. 相似文献
26.
On experimental setup in bioelectromagnetics 总被引:1,自引:1,他引:0
Bioeffects created by electromagnetic field (EMF) are the subject of intensive studies. This paper critically considers estimations
of exposure to EMF in bioelectromagnetic experiments. Results of calculations presented herein show the significant role of
the presence of conducting bodies (the exposure system) near an object under test on EMF energy absorption as well as mutual
interactions between simultaneously exposed objects. Our aims herein are twofold: firstly to find a way to refer measurement
results to free-space conditions in order to enable comparison of results obtained in different laboratories, and secondly
to show that EMF energy absorption in any exposed object is different and that this difference is a function of the size of
the exposure system, the number of exposed objects, and the particular properties (i.e., the electromagnetic structure) of
the objects. In the authors’ opinion the existence of interactions caused by the presence of the exposure system and other
exposed objects is a reason why remarkable differences are observed between experiments performed even under supposedly identical
conditions. The presented considerations and conclusion suggest wider participation of physicists and engineers in bioelectromagnetic
experiments in order to ensure the correctness of metrological aspects of these experiments. 相似文献
27.
Urbanization and its impact on groundwater: a remote sensing and GIS-based assessment approach 总被引:1,自引:0,他引:1
The perils of unplanned urbanization and increasing pressure of human activities on hydro-geomorphologic system often result
in modification of the existing recharge mechanism, which leads to many environmental consequences. In the present research,
an attempt has been made to investigate the applicability of remote sensing and geographical information system (GIS) in dealing
with spatial and temporal variability of dynamic phenomena, like urbanization and its impact on groundwater. This paper covers
primarily, quantitative and qualitative impacts of urban growth on the behavior of aquifer in Ajmer city (India). Urban growth
of the Ajmer city in last 17 years has been estimated from the satellite images. Database related to urbanization and groundwater
has been created in GIS. Groundwater recharge has been computed using a water balance approach known as Water Level Fluctuation
Methodology. Recharge estimation methodology has been implemented in GIS to introduce the spatial variability of hydro-geological
characteristics. Further, temporal and spatial variations in groundwater quality and quantity have been correlated with urban
growth using overlay analysis in GIS. The study reveals a general decline in water table and quality with urbanization. Further,
remote sensing and GIS technologies have been found useful in assessment of spatial and temporal phenomena of urbanization
and its impact on groundwater system. 相似文献
28.
A new method for separation and preconcentration of trace amounts of Cu(II), Ni(II), Pb(II), Cd(II) and Mn(II) ions in various matrices was proposed. The method is based on the adsorption and chelation of the metal ions on a column containing Amberlite XAD-1180 resin impregnated with 1-(2-thiazolylazo)-2-naphthol (TAN) reagent prior to their determination by flame atomic absorption spectrometry (FAAS). The effect of pH, type, concentration and volume of eluent, sample volume, flow rates of sample and elution solutions, and interfering ions have been investigated. The optimum pH for simultaneous retention of all the metal ions was 9. Eluent for quantitative elution was 20 ml of 2 mol l(-1) HNO(3). The optimum sample and eluent flow rates were found as 4 ml min(-1), and also sample volume was 500 ml, except for Mn (87% recovery). The sorption capacity of the resin was found to be 0.77, 0.41, 0.57, and 0.30 mg g(-1) for Cu(II), Ni(II), Cd(II), and Mn(II), respectively. The preconcentration factor of the method was 200 for Cu(II), 150 for Pb(II), 100 for Cd(II) and Ni(II), and 50 for Mn(II). The recovery values for all of the metal ions were > or = 95% and relative standard deviations (RSDs) were < or = 5.1%. The detection limit values were in the range of 0.03 and 1.19 microg l(-1). The accuracy of the method was confirmed by analysing the certified reference materials (TMDA 54.4 fortified lake water and GBW 07605 tea samples) and the recovery studies. This procedure was applied to the determination of Cu(II), Ni(II), Pb(II), Cd(II) and Mn(II) in waste water and lake water samples. 相似文献
29.
Nevzat Damla Uğur Cevik Ali Ihsan Kobya Ahmet Celik Necati Celik 《Environmental monitoring and assessment》2010,170(1-4):457-466
The activity concentrations of 226Ra, 232Th, and 40K in lime and gypsum samples used as building materials in Turkey were measured using gamma spectrometry. The mean activity concentrations of 226Ra, 232Th, and 40K were found to be 38 ± 16, 20 ± 9, and 156 ± 54 Bq kg???1 for lime and found to be 17 ± 6, 13 ± 5, and 429 ± 24 Bq kg???1 for gypsum, respectively. The radiological hazards due to the natural radioactivity in the samples were inferred from calculations of radium equivalent activities (Raeq), indoor absorbed dose rate in the air, the annual effective dose, and gamma and alpha indices. These radiological parameters were evaluated and compared with the internationally recommended limits. The experimental mass attenuation coefficients (μ/ρ) of the samples were determined in the energy range 81–1,332 keV. The experimental mass attenuation coefficients were compared with theoretical values obtained using XCOM. It is found that the calculated values and the experimental results are in good agreement. 相似文献
30.