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371.
Pair bonds can end in two different ways: either death of the partner or divorce, where the frequency of divorce varies enormously
among bird species, from 0% to 100%. To better understand this variation, we created and analyzed the largest dataset so far,
consisting of 158 species and 20 variables that quantify the species’ body size, life history, diet, and other characteristics.
Our results suggest that species with a high divorce rate have a high mortality rate, tend to be ornamented and sexually dichromatic,
live colonially, and form part-time rather than continuous partnerships. Traits quantifying body size or life history are
often nonlinearly related with divorce rate. These nonlinearities might (partly) be caused by nonlinear relationships of the
same traits with mortality rate which is, in turn, linearly related with divorce rate. In contrast to what has been found
previously, mortality rate appears as a key factor for divorce rate in our study. This makes sense, as the likelihood that
a partner survives from one year to the next decreases with increasing mortality rate, diminishing the likely success of a
partner that attempts to locate its previous partner. We also found taxonomic differences in divorce rate. Specifically, Anseriformes
have an exceptionally low divorce rate, which, however, can be explained by the generally important determinants of divorce
rate: They also have a lower mortality rate, lower degree of ornamentation and coloniality, and more continuous partnerships
than members of other orders.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
372.
Fish abundance is often better predicted by microhabitat variables on continuous reefs than on isolated patch reefs. Although
this was suggested to stem from reduced post-recruitment relocation, this has not been shown experimentally. We found the
relationship between the presence of a coral-dwelling fish, Dascyllus marginatus, and the size of its coral host to differ between corals on continuous reefs and the sparsely distributed corals on sandy
bottoms. Empty transplanted corals were colonized exclusively by new recruits when on the sandy bottom, and both by new recruits
and post-recruitment dispersal of adults when on the continuous reef. New recruits settled predominantly into small corals,
although analyses of recruitment patterns were confounded by low recruitment in the studied years. Both tank experiments and
field survey data suggest that the presence of recruits in small corals is at least partially driven by predation by the dottyback,
Pseudochromis olivaceus, which lives predominantly in large corals within both habitats. Consequently, we suggest that the relationship between fish
presence and coral size differs between the habitats due to coral size dependent predation on recruits and variability in
the importance of direct recruitment to replenish fish populations. 相似文献
373.
Sonter Laura J. Gordon Ascelin Archibald Carla Simmonds Jeremy S. Ward Michelle Metzger Jean Paul Rhodes Jonathan R. Maron Martine 《Ambio》2020,49(4):892-902
Ambio - Offsetting—trading losses in one place for commensurate gains in another—is a tool used to mitigate environmental impacts of development. Biodiversity and carbon are the most... 相似文献
374.
Le Hoang-Anh Lambrechts Jonathan Ortleb Sigrun Gratiot Nicolas Deleersnijder Eric Soares-Frazão Sandra 《Environmental Fluid Mechanics》2020,20(4):923-951
Environmental Fluid Mechanics - The accurate simulation of wetting–drying processes in floodplains and coastal zones is a challenge for hydrodynamic modelling, especially for long time... 相似文献
375.
Benefit‐Cost Analysis of Integrated Water Resource Management: Accounting for Interdependence in the Yakima Basin Integrated Plan
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Jonathan Yoder Jennifer Adam Michael Brady Joseph Cook Stephen Katz Shane Johnston Keyvan Malek John McMillan Qingqing Yang 《Journal of the American Water Resources Association》2017,53(2):456-477
Integrated water resource management (IWRM) requires accounting for many interrelated facets of water systems, water uses and stakeholders, and water management activities. The consequence is that project analysis must account for the nonseparability among the component parts of IWRM plans. This article presents a benefit‐cost (B‐C) analysis of a set of projects included in the Yakima Basin Integrated Plan proposed for the Yakima Basin in south‐central Washington State. The analysis accounts for interdependence among proposed water storage projects and between water storage and water market development in the context of historical and more adverse projected future climate scenarios. Focusing on irrigation benefits from storage, we show that the value of a given proposed storage project is lower when other proposed storage projects in the basin are implemented, and when water markets are functioning effectively. We find that none of the water storage projects satisfy a B‐C criterion, and that assuring proposed instream flow augmentation is less expensive by purchasing senior diversion rights than relying on new storage to provide it. 相似文献
376.
Effects of Impervious Area and BMP Implementation and Design on Storm Runoff and Water Quality in Eight Small Watersheds 总被引:1,自引:0,他引:1
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Brent T. Aulenbach Mark N. Landers Jonathan W. Musser Jaime A. Painter 《Journal of the American Water Resources Association》2017,53(2):382-399
The effects of increases in effective impervious area (EIA) and the implementation of water quality protection designed detention pond best management practices (BMPs) on storm runoff and stormwater quality were assessed in Gwinnett County, Georgia, for the period 2001‐2008. Trends among eight small watersheds were compared, using a time trend study design. Significant trends were detected in three storm hydrologic metrics and in five water quality constituents that were adjusted for variability in storm characteristics and climate. Trends in EIA ranged from 0.10 to 1.35, and changes in EIA treated by BMPs ranged from 0.19 to 1.32; both expressed in units of percentage of drainage area per year. Trend relations indicated that for every 1% increase in watershed EIA, about 2.6, 1.1, and 1.5% increases in EIA treated by BMPs would be required to counteract the effects of EIA added to the watersheds on peak streamflow, stormwater yield, and storm streamflow runoff, respectively. Relations between trends in EIA, BMP implementation, and water quality were counterintuitive. This may be the result of (1) changes in constituent inputs in the watersheds, especially downstream of areas treated by BMPs; (2) BMPs may have increased the duration of stormflow that results in downstream channel erosion; and/or (3) spurious relationships between increases in EIA, BMP implementation, and constituent inputs with development rates. 相似文献
377.
Cessna AJ Donald DB Bailey J Waiser M Headley JV 《Journal of environmental quality》2006,35(6):2395-2401
Sulfonylurea herbicides are applied at relatively low rates (3 to 40 g ha(-1)) to control weeds in a variety of crops across the Canadian prairies. Because of their high phytotoxicity and the likelihood of their transport in surface runoff, there is concern about their possible impact to aquatic ecosystems. Little is known, however, about their persistence and behavior in aquatic ecosystems. To assess persistence in aquatic ecosystems, three prairie farm dugouts (ponds) were fortified with either thifensulfuron-methyl {methyl 3-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]amino]sulfonyl]-2-thiophenecarboxylate}, ethametsulfuron-methyl {methyl 2-[[[[[4-ethoxy-6-(methylamino)-1,3,5-triazin-2-yl]amino]carbonyl]amino]sulfonyl]benzoate} or metsulfuron-methyl {methyl 2-[[[[(4-methoxy-6-methyl-1,3,5-triazinyl)amino]carbonyl]amino]sulfonyl]benzoate}. The decreasing order of persistence of environmentally relevant concentrations (1 to 4.6 microg L(-1)) of these herbicides in dugout water over the June to October period was metsulfuron-methyl>ethametsulfuron-methyl>thifensulfuron-methyl. The corresponding dissipation half-lives (DT(50)) of 84, 30, and 16 d, respectively, are in the same relative order as the recropping intervals for these herbicides. Thifensulfuron-methyl showed a biphasic dissipation with slower dissipation during the winter months. In contrast, the dissipation of metsulfuron-methyl, the sulfonylurea herbicide with the longest DT(50), was somewhat enhanced under winter conditions. One of the major routes of sulfonylurea herbicide dissipation was removal from the water column when dugout water was lost during hydrological discharge. The relatively long persistence of these herbicides in water indicates that partitioning into sediments was minimal, the sulfonylurea and methyl ester linkages in these compounds were resistant to hydrolysis in weakly alkaline waters, and that microbial and photolytic degradation in dugout waters were slow. 相似文献
378.
George Yu. Sofronov Gareth E. Evans Jonathan M. Keith Dirk P. Kroese 《Environmental Modeling and Assessment》2009,14(5):577-584
The genomes of complex organisms, including the human genome, are highly structured. This structure takes the form of segmental
patterns of variation in various properties and may be caused by the division of genomes into regions of distinct function,
by the contingent evolutionary processes that gave rise to genomes, or by a combination of both. Whatever the cause, identifying
the change-points between segments is potentially important, as a means of discovering the functional components of a genome,
understanding the evolutionary processes involved, and fully describing genomic architecture. One property of genomes that
is known to display a segmental pattern of variation is GC content. The GC content of a portion of DNA is the proportion of
GC pairs that it contains. Sharp changes in GC content can be observed in human and other genomes. Such change-points may
be the boundaries of functional elements or may play a structural role. We model genome sequences as a multiple change-point
process, that is, a process in which sequential data are separated into segments by an unknown number of change-points, with
each segment supposed to have been generated by a different process. We consider a Sequential Importance Sampling approach
to change-point modeling using Monte Carlo simulation to find estimates of change-points as well as parameters of the process
on each segment. Numerical experiments illustrate the effectiveness of the approach. We obtain estimates for the locations
of change-points in artificially generated sequences and compare the accuracy of these estimates to those obtained via Markov
chain Monte Carlo and a well-known method, IsoFinder. We also provide examples with real data sets to illustrate the usefulness
of this method. 相似文献
379.
In the frame of assessing exposure to nanostructured particles, the aim of this work is to study the performance of a new device devoted to the real-time measurement of nanostructured aerosol: the meDiSC (Diffusion Size Classifier, Matter Engineering, Switzerland). This instrument is based on unipolar diffusion charging of particles which are then collected successively in diffusion and filtration stages. From currents measured in these stages, the instrument is capable of determining aerosol mean size and number concentration. These data were compared to reference measurements regarding monodisperse aerosols in a range from 20 to 700 nm; the relative biases were found unsatisfying. This led us to investigate the principle of the instrument. Consequently, the charging law of the diffusion charger was experimentally established, as well as the calibration curve allowing the determination of the mean size of the particles. The latter analysis was completed by a model based on diffusion theory. Our results indicate the possibility to improve the range of size measurement up to 350 nm. Measured particle size and number concentration were also used to calculate geometric surface-area concentration; the experimental data were compared to a reference calculated surface-area concentration. The results demonstrate the possibility to evaluate this parameter within acceptable uncertainty. In a second step, the meDiSC was challenged with polydisperse aerosols. It was observed that meDiSC overestimates particle size by a factor 1.7, while particle number concentrations are found within ±40% of the reference. The model applied to polydisperse aerosols indicates that polydispersity little influences particle size up to 300 nm while geometric standard deviation remains below 1.7. 相似文献
380.
George Mitri Manal Nader Irna Van der Molen Jonathan Lovett 《Environmental monitoring and assessment》2014,186(11):7655-7672
Repetitive armed conflicts may be directly and indirectly responsible for severe biophysical modification to the environment. This, in turn, makes land more susceptible to degradation. Mapping and monitoring land degradation are essential for designing and implementing post-conflict recovery plans and informed policy decisions. The aim of this work was to evaluate the effect of repetitive armed conflicts on land degradation along the coastal zone of North Lebanon using multi-temporal satellite data. The specific objectives were to (1) identify a list of indicators for use in conjunction with satellite remote sensing, (2) monitor land cover change throughout repetitive events of armed conflicts and (3) model the effect of repetitive armed conflicts on land degradation. The methodology of work comprised the use of multi-temporal Landsat images and literature review data in GEographic Object-Based Image Analysis (GEOBIA) approach. The work resulted in the development of (1) a list of indicators to be employed, (2) land cover change detection maps with the use of multi-temporal Landsat images and, consequently, a fire risk associated with changes in vegetation cover throughout repetitive armed conflict events, and (3) an integrated approach for modelling the effect of repetitive armed conflicts on land degradation with the use of a composite land degradation index (CLDI). The final synthetic map showed four classes of exposure to land degradation associated with repetitive armed conflicts. Data collected from field visits showed that the final classification results highly reflected (average of 90 %) the effect of repetitive armed conflicts on the different classes of exposure to land degradation. 相似文献