全文获取类型
收费全文 | 99篇 |
免费 | 1篇 |
专业分类
废物处理 | 2篇 |
环保管理 | 21篇 |
综合类 | 38篇 |
基础理论 | 18篇 |
污染及防治 | 16篇 |
评价与监测 | 2篇 |
社会与环境 | 3篇 |
出版年
2023年 | 2篇 |
2022年 | 4篇 |
2021年 | 3篇 |
2020年 | 3篇 |
2019年 | 1篇 |
2018年 | 2篇 |
2016年 | 4篇 |
2015年 | 1篇 |
2014年 | 2篇 |
2013年 | 8篇 |
2012年 | 4篇 |
2011年 | 3篇 |
2010年 | 2篇 |
2009年 | 2篇 |
2008年 | 1篇 |
2007年 | 5篇 |
2006年 | 5篇 |
2003年 | 3篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1982年 | 2篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1971年 | 2篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1964年 | 1篇 |
1963年 | 1篇 |
1962年 | 2篇 |
1961年 | 2篇 |
1960年 | 2篇 |
1955年 | 4篇 |
1954年 | 2篇 |
1948年 | 1篇 |
1932年 | 1篇 |
1922年 | 1篇 |
1920年 | 1篇 |
排序方式: 共有100条查询结果,搜索用时 15 毫秒
31.
32.
One frequent explanation for the failure of biological invasions is the Allee effect: due to positive density dependence, initially small invading populations may fail to establish and spread. Populations released for biological control are similar to fortuitous invading populations and may therefore suffer from Allee effects. However, unlike fortuitous invasions, biological control allows the experimental manipulation of initial population size and, thus, offers a unique opportunity to test for the occurrence of Allee effects. We manipulated the initial size of 45 populations of a parasitoid wasp introduced for the biological control of a phytophagous insect and followed the population dynamics of both parasitoids and hosts during three years. Our results suggest an absence of Allee effects but clear negative density dependence instead: (1) the probability of establishment after three years was not affected by initial population size; (2) net reproductive rate was highest at low parasitoid density and high host density; (3) the sex ratio, reflecting the proportion of virgin females, did not increase at low density, suggesting that low densities did not impede mate-finding; (4) the depression of host populations did not depend upon the number of parasitoids introduced. This is, to our knowledge, the first experimental test of the Allee effect in an invading parasitoid. It leads us to propose that a number of behavioral and life-history features of many parasitoids could protect them from Allee effects. 相似文献
33.
34.
Land cover change and abrupt environmental impacts on Javan volcanoes, Indonesia: a long-term perspective on recent events 总被引:1,自引:1,他引:0
Based on a presentation of the spectacularly abrupt environmental and societal processes occurring on Java since the 1990s, and using that as an analogue to compare their consequences with the known environmental history of the island, we unravel the relative contributions of natural and human impacts in shaping the environment of Java. Our work is based on remote sensing, Geographical Information System analysis, field-based observations and measurements of responses to abrupt land cover changes in the last 10 years. Ecological disturbance has been endemic to the long-term history of Java, but montane forests on volcanoes have since ca. 1990 become the last frontier of colonisation and are for the first time rapidly receding. We reveal how human disturbance of natural ecosystems, today as in the past, tends to be the greatest where resistance is the least. This appears true within the regional setting of Southeast Asia, where Javan forests since the last glaciation have constituted a biogeographical ecotone with a limited natural ability to regenerate after some imbalance. It is equally true at the scale of single events where humans will turn a natural disturbance to their own advantage. Overall, it remains difficult to deconvolve the signals of spontaneous human impacts and of localised natural events such as volcanic activity, El Niño-related forest fires or longer climatic anomalies because humans are opportunistic in their attitudes to natural variability and so the two are often inextricably linked. The clearest impact on land cover and land degradation comes from the history of state-organised deforestation, whether colonial or indigenous, because its impact has been systematic, pervasive and regionally consistent. Javan environments have shown astonishing signs of resilience under the abrupt, cumulative impacts that have been inflicted over the last four centuries in successive iterations, possibly because the high-energy tropical and volcanic environment is a system in which sediment turnover is naturally rapid and where past scars of land degradation either heal rapidly or are soon destroyed by younger events. However, the volcanoes are the island’s keystone reservoirs of water, sediment and biodiversity and command the geomorphic metabolism of the lowlands. By removing forests from increasingly crowded mountain slopes, Javanese society is following a trajectory in which new nonlinear responses to environmental hazards and change may limit our capacity to anticipate and contain environmental risk to human life and property. 相似文献
35.
36.
Sauphanor B Franck P Lasnier T Toubon JF Beslay D Boivin T Bouvier JC Renou M 《Die Naturwissenschaften》2007,94(6):449-458
The behavioral and electroantennographic responses of Cydia pomonella (L.) to the ripe pear volatile ethyl (2E,4Z)-2,4-decadienoate (Et-E,Z-DD), were compared in insecticide-susceptible and -resistant populations originating from southern France. A dose–response
relationship to this kairomonal attractant was established for antennal activity and did not reveal differences between susceptible
and resistant strains. Conversely, males of the laboratory strains expressing metabolic [cytochrome P450-dependent mixed-function
oxidases (mfo)] or physiological (kdr-type mutation of the sodium-channel gene) resistance mechanisms exhibited a significantly
higher response to Et-E,Z-DD than those of the susceptible strain in a wind tunnel experiment. No response of the females to this kairomone could be
obtained in our wind-tunnel conditions. In apple orchards, mfo-resistant male moths were captured at significantly higher
rates in kairomone-baited traps than in traps baited with the sex pheromone of C. pomonella. Such a differential phenomenon was not verified for the kdr-resistant insects, which exhibited a similar response to both
the sex pheromone and the kairomonal attractant in apple orchards. Considering the widespread distribution of metabolic resistance
in European populations of C. pomonella and the enhanced behavioral response to Et-E,Z-DD in resistant moths, the development of control measures based on this kairomonal compound would be of great interest for
the management of insecticide resistance in this species. 相似文献
37.
Pignon Baptiste Borel Cynthia Lajnef Mohamed Richard Jean-Romain Szöke Andrei Hemery François Leboyer Marion Foret Gilles Schürhoff Franck 《Environmental science and pollution research international》2022,29(59):88577-88586
Environmental Science and Pollution Research - Particulate matters with a diameter of less than 10 µm (PM10) or less than 2.5 µm (PM2.5) are major air pollutants. Their... 相似文献
38.
39.
Jacobus L.A. Hofstede Johannes Becherer Hans Burchard 《Journal of Coastal Conservation》2018,22(1):71-78
Accelerated sea level rise may have serious implications for the Wadden Sea ecosystem in its present state. If sediment accumulation rates on the extensive intertidal flats stay behind sea level rise, the flats will eventually submerge. Drowning of the flats has negative consequences for nature conservation and for coastal risk management. Based upon an evaluation of steady state relations for Wadden Sea tidal basins, Hofstede (Zeitschrift für Geomorphologie 59(3): 377-391, 2015) postulated that the capacity of these basins to balance sea level rise by accumulation on intertidal flats seems positively related to mean tidal range. In the present study, morphodynamical simulations with a numerical model were performed for two tidal basins in the German Wadden Sea to verify the empirically established hypothesis. The following conclusions are established. Larger mean tidal range improves the capacity of Wadden Sea tidal basins to balance sea level rise. Wadden Sea intertidal flats are effective sediment sinks and seem quite resilient against (higher rates of) sea level rise. Finally, subtidal gullies may constitute a significant sediment source for accumulation on intertidal flats in response to sea level rise. With respect to the limited comparability of the two investigated tidal systems, morphodynamical modelling of all Wadden Sea tidal systems should be conducted. 相似文献
40.