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The theory of life history evolution assumes trade-offs between competing fitness traits such as reproduction, somatic growth, and maintenance. One prediction of this theory is that if large individuals have a higher reproductive success, small/young individuals should invest less in reproduction and allocate more resources in growth than large/old individuals. We tested this prediction using the common toad (Bufo bufo), a species where mating success of males is positively related to their body size. We measured testes mass, soma mass, and sperm stock size in males of varying sizes that were either (1) re-hibernated at the start of the breeding season, (2) kept without females throughout the breeding season, or (3) repeatedly provided with gravid females. In the latter group, we also estimated fertilization success and readiness to re-mate. Contrary to our predictions, the relationship between testes mass and soma mass was isometric, sperm stock size relative to testes mass was unrelated to male size, fertilization success was not higher in matings with larger males, and smaller males were not less likely to engage in repeated matings than larger males. These results consistently suggest that smaller males did not invest less in reproduction to be able to allocate more in growth than larger males. Causes for this unexpected result may include relatively low year-to-year survival, unpredictable between-year variation in the strength of sexual selection and low return rates of lowered reproductive investment.  相似文献   
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It can be stated in general that (with the exception of agriculture) the Hungarian economy, because of its outdated technologies, is a bigger threat to the environment than countries of Western Europe. However, as the volume of economic output, per capita consumption and the number of motor vehicles is considerably lower than those in more advanced industrial nations, by most indicators low per capita figures put Hungary in a better position. Still, we must remember that the EU's environmental policy puts heavy emphasis on the efficient utilization of resources and environmental efficiency, calculated against pollution generated in the course of creating units of national wealth and the amount of energy and natural resources required to it. By these standards, Hungary lags far behind the West European model.The problem is compounded by the fact that, while nations of Western Europe had created environmental infrastructure (i.e., wastewater disposal and treatment, waste management) in an earlier phase of their economic development, Hungary is only now embarking on a similar project. Indeed, the existing gap between utility services of drinking water and sewage disposal and treatment, and large amounts of untreated and illegally dumped waste lead to serious environmental damage. Although the state of the country's natural environment is considered satisfactory, factors outlined above indicate there are many responsibilities ahead of us if we are to meet western environmental standards.  相似文献   
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Environmental Science and Pollution Research - This paper offers a novel application of our model worked out in Maple environment to help understand the very complex transport processes in...  相似文献   
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Environmental Science and Pollution Research - We worked out a method in Maple environment to help understand the difficult transport processes in horizontal subsurface flow constructed wetlands...  相似文献   
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Inherited system features and challenges that can hinder urban planning initiatives must be taken into consideration before a path towards a sustainable future can be established. By putting the lock-in effect under scrutiny, it is possible to gain valuable insight to emphasize positive lock-ins and to prevent maladaptation and unsustainable solutions. This paper aims to review the current trends of urban studies regarding sustainability, resilience, and the lock-in effect, focusing on both hot topics and mutual integration by following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Reviews (PRISMA-ScR protocol) and analyzing the top-cited articles on these topics from 2015 to 2021 in the Web of Science database. Based on the revised literature, the potential lock-ins of climate-friendly and sustainable urban development are not adequately discussed. Moreover, while urban sustainability and resilience are often treated as overlapping areas, there is a lack of publications that carefully examine their interlinked long-term perspectives for any hindering effects.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-022-01817-w.  相似文献   
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Abstract

Oil products are widely used in orchards and on grapevine as pesticides, or adjuvants to pesticides. We aimed to get information on the efficacy of formulated rape seed oil against phytophagous mites in grapevine and its effect on predatory mites. Formulated rape seed oil (TELMIONR) from the Temmen GmbH, Germany was used in field trials at 0.5% and 1 %.

For phytophagous mites TELMIONR had an efficacy of 90,1% and 91,2% for 05% and for 1%, respectively. For Phytoseiidae there was no side effect at 0.5% and 1%. For Tydeiidae there was no side effect at 0.5% and a moderate toxicity (43.1%) at 1%. On the basis of our results TELMIONR seems to fit well into Integrated Pest Management or Organic Production in grapevine.  相似文献   
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Acute and chronic toxicity of benzotriazoles to aquatic organisms   总被引:2,自引:1,他引:2  

Purpose

Resulting from their intensive use as corrosion inhibitors in aircraft deicing and anti-icing fluids (ADAF) and for silver protection in dishwasher detergents benzotriazoles (BTs) are widespread in European surface waters. The current study aimed on an ecotoxicological characterization of 1H-benzotriazole (1H-BT) and 5-methyl-1H-benzotriazole (5MBT).

Methods

Acute and chronic OECD guideline tests were conducted with primary producers (Desmodesmus subspicatus, Lemna minor) and two daphnia species (Daphnia magna, Daphnia galeata) to characterize the hazard of these chemicals. Additionally, the estrogenic activity of both BTs was analyzed in vitro using a recombinant yeast estrogen screen (YES).

Results

Both BTs revealed significant effects in acute and chronic experiments, but exhibited no estrogenic activity in the YES. The algal growth test displayed an inhibited cell number increase with effect concentration (EC) values of EC10 1.18 and 2.86?mg?l-1 for 1H-BT and 5MBT, respectively. In the Lemna test, EC10 values were 3.94?mg?l-1 (1H-BT) and 2.11?mg?l-1 (5MBT). D. magna was also affected with EC50 (48?h) values of 107?mg?l-1 for 1H-BT and 51.6?mg?l-1 for 5MBT. D. galeata was more sensitive with an EC50 (48?h) of 14.7?mg 1H-BT l-1 and 8.13?mg 5MBT l-1. In the 21-day reproduction tests with D. magna, the EC10 for 5MBT was 5.93?mg?l-1 while 1H-BT showed no adverse effects. D. galeata turned out to be more sensitive in the chronic study with EC10 values of 0.97?mg?l-1 for 1H-BT and 0.40?mg?l-1 for 5 MBT.

Conclusion

Because BTs are regularly found in the aquatic environment at lower ??g l-1 concentrations reflecting their persistence and poor elimination during wastewater treatment processes, a preliminary risk assessment was conducted. There is little indication that BTs pose a risk for aquatic ecosystems at current exposure levels during most of the year. However, it cannot be excluded that in winter with a higher usage of ADAFs environmental concentrations may well exceed the level that is considered safe for aquatic organisms.  相似文献   
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