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41.
Assessing river flood risk and adaptation in Europe—review of projections for the future 总被引:3,自引:0,他引:3
Zbigniew W. Kundzewicz Nicola Lugeri Rutger Dankers Yukiko Hirabayashi Petra Döll Iwona Pińskwar Tomasz Dysarz Stefan Hochrainer Piotr Matczak 《Mitigation and Adaptation Strategies for Global Change》2010,15(7):641-656
Flood damages have exhibited a rapid upward trend, both globally and in Europe, faster than population and economic growth.
Hence, vigorous attempts of attribution of changes have been made. Flood risk and vulnerability tend to change over many areas,
due to a range of climatic and nonclimatic impacts whose relative importance is site-specific. Flooding is a complex phenomenon
and there are several generating mechanisms, among others intense and/or long-lasting precipitation, snowmelt, ice jam. Projected
climate-driven changes in future flood frequency are complex, depending on the generating mechanism, e.g., increasing flood
magnitudes where floods result of heavy rainfall and possibly decreasing magnitudes where floods are generated by spring snowmelt.
Climate change is likely to cause an increase of the risk of riverine flooding across much of Europe. Projections of flood
hazard in Europe based on climatic and hydrological models, reviewed in this paper, illustrate possible changes of recurrence
of a 100-year flood (with probability of exceedance being 1-in-100 years) in Europe. What used to be a 100-year flood in the
control period is projected to become either more frequent or less frequent in the future time horizon of concern. For a large
part of the continent, large flooding is projected to become more commonplace in future, warmer climate. Due to the large
uncertainty of climate projections, it is currently not possible to devise a scientifically-sound procedure for redefining
design floods (e.g. 100-year flood) in order to adjust flood defenses. For the time being, we recommend to adjust design floods
using a “climate change factor” approach. 相似文献
42.
43.
Christian Ramp Wilhelm Hagen Per Palsbøll Martine Bérubé Richard Sears 《Behavioral ecology and sociobiology》2010,64(10):1563-1576
Analyses of social structures in baleen whales are rare, and so far, they are thought to consist of mostly short and unstable
associations. We investigated the association patterns of individual humpback whales from a summer feeding aggregation in
the Gulf of St. Lawrence from 1997 to 2005. Photo-identified animals were sexed using genetic methods and were grouped into
five categories: juvenile males/females, mature males and lactating/non-lactating females. We calculated half-weight association
indices within and between the groups and found that 45% of the observation showed single animals and another 45% small groups
(two to three) consisting mainly of mature animals besides lactating females. Using permutation tests, we found evidence for
long-term associations between mature males and non-lactating females as well as among non-lactating females. Standardised
lagged association rates revealed that these male–female groups disassociated quickly over about 2 weeks, whereas associations
increased again towards the beginning of the breeding season. Non-lactating females of similar age engaged in multi-seasonal
stable pairs for up to six consecutive feeding seasons; no mature male–female association was observed in consecutive years.
The females with the most stable and long-term associations also had the highest reproductive output. While the risk of predation
could not explain these long-term bonds, feeding cooperation seemed the most plausible explanation for group forming behaviour
during the summer months. 相似文献
44.
Gergely Hegyi Balázs Rosivall Eszter Szöllősi Marcel Eens János Török 《Behavioral ecology and sociobiology》2011,65(8):1647-1658
Nestling growth is known as an important determinant of fitness in altricial birds, but its evolutionary potential has been
debated, and little is known about detailed patterns of current selection on growth. Relationships are often reported between
nestling growth and attributes of nestlings and parents, but the interpretation of these depends on the advantages a given
growth difference confers to the chicks. Increased growth may have positive, negative or context-dependent effects on offspring
fitness, but these effects are largely unknown in natural populations. We measured growth trajectories of body mass in fostered
broods of collared flycatchers (Ficedula albicollis) in 3 years of contrasting food conditions. We examined the growth of young and their recruitment probability to the breeding
population in relation to year quality, hatching rank, sex, paternal age and paternal attractiveness. We also looked at the
interactive effects of growth and intrinsic offspring attributes on recruitment probability. The predictors of nestling growth
and those of recruitment did not agree. Moreover, the recruitment consequences of a given nestling growth rate were significantly
influenced by nestling rank and paternal ornamentation. Differential recruitment effects of nestling growth in relation to
parental traits and nestling attributes suggest that using growth as a generally applicable measure of nestling quality may
not be justified. These findings also have implications for morphological evolution and the indicator value of sexual signals. 相似文献
45.
Roy Pöllänen 《Environmental monitoring and assessment》1993,28(3):239-254
The possibility has been investigated of using the PIXE method to yield long and reliable time series for indicating changes in the environment, with moths or butterflies as a sample target. The suitability of this approach was demonstrated by studying standard deviations of measurements of single moths and those of populations of moths. The properties of targeting at different anatomical sites were investigated and the wing gave the most stable results, perhaps because its metabolic development is completed at the imago (newborn butterfly) stage. According to test measurements of different populations it seems possible to use moth or butterfly wing measurements to study environmental changes over the past century or so using moth or butterfly collections. 相似文献
46.
47.
48.
This editorial is based on a paper first produced by Winfried Böll entitled, A Global Emergency Plan for the Environment which appeared inThe Crisis of Global Environment: Demands for Global Politics published by The Foundation Development and Peace in 1989. Winfried Böll is the retired Ministerial Director of the Ministry for Economic Co-operation, West Germany. He lectures at the University of Duisburg on matters related to foreign aid and government and administration, he is also an advisor to the Board of the Foundation Development and Peace. The Foundation was established in 1987 at the initiative of former West German Chancellor, Willy Brandt. Its Executive Board, as well as its Board of Trustees and its members are composed of distinguished personalities from political, social, economic and scientific life who share a sense of global responsibility. The Foundation is non-partisan and non-profit-making.Its objectives are summarised below: 相似文献
49.
Three-year-old clonal spruce trees, kept in growth chambers, were treated with ozone and acid mist during a period of 14 months. One half of the trees were grown on an acidic sandy soil, the other half on a calcareous soil rich in carbonate. At the end of the fumigation period, carbohydrates (glucose, fructose, sucrose, raffinose, starch, glucose-1-phosphate and fructose-6-phosphate) and parameters of the energy status (ATP-, AdN-(ATP + ADP + AMP)- levels, ATP/ADP-ratios and adenylate-energy-charge-(AEC)-values) were determined in the current-year's needles. The results indicate that the metabolic status of a plant tissue is not only influenced by the nature of the air pollutants. Soil factors play an important role in metabolic changes within the plant and are thus of relevance in the manifestation of damage symptoms. 相似文献
50.
Peery MZ Beissinger SR House RF Bérubé M Hall LA Sellas A Palsbøll PJ 《Ecology》2008,89(10):2746-2759
Source-sink dynamics have been suggested to characterize the population structure of many species, but the prevalence of source-sink systems in nature is uncertain because of inherent challenges in estimating migration rates among populations. Migration rates are often difficult to estimate directly with demographic methods, and indirect genetic methods are subject to a variety of assumptions that are difficult to meet or to apply to evolutionary timescales. Furthermore, such methods cannot be rigorously applied to high-gene-flow species. Here, we employ genetic parentage assignments in conjunction with demographic simulations to infer the level of immigration into a putative sink population. We use individual-based demographic models to estimate expected distributions of parent-offspring dyads under competing sink and closed-population models. By comparing the actual number of parent-offspring dyads (identified from multilocus genetic profiles) in a random sample of individuals taken from a population to expectations under these two contrasting demographic models, it is possible to estimate the rate of immigration and test hypotheses related to the role of immigration on population processes on an ecological timescale. The difference in the expected number of parent-offspring dyads between the two population models was greatest when immigration into the sink population was high, indicating that unlike traditional population genetic inference models, the highest degree of statistical power is achieved for the approach presented here when migration rates are high. We used the proposed genetic parentage approach to demonstrate that a threatened population of Marbled Murrelets (Braclhyrarmphus marmotus) appears to be supplemented by a low level of immigration (approximately 2-6% annually) from other populations. 相似文献