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991.
Size assessment in simulated territorial encounters between male green frogs (Rana clamitans) 总被引:2,自引:0,他引:2
Mark A. Bee Stephen A. Perrill Patrick C. Owen 《Behavioral ecology and sociobiology》1999,45(3-4):177-184
We examined the ability of male green frogs to assess the size of an opponent based on the dominant frequency of their advertisement
call, which is negatively correlated with size, using synthetic stimuli to simulate intruders of different sizes. In one field
playback experiment, we broadcast a pair of stimuli representing a small and a large male; in a second experiment, we broadcast
calls of a medium and a large male. In both experiments, males produced calls with significantly lower dominant frequencies
in response to each stimulus. Contrast analyses revealed that males lowered the dominant frequency of their calls more in
response to the large-male stimulus than in responses to the small- and medium-male stimuli. In the second experiment, males
also responded to the large-male stimulus by calling at higher rates. There were no differences in mean note duration or the
number of moves made toward or around the playback speaker in response to any stimulus. Thus, the frequency of an opponent's
calls elicits a differential modification of calling behavior, primarily in the form of differential dominant frequency alteration,
suggesting that males use dominant frequency to assess the size of opponents during aggressive encounters.
Received: 17 April 1998 / Accepted after revision: 7 October 1998 相似文献
992.
中空柱状生物膜载体在处理工业废水工程中的应用 总被引:5,自引:0,他引:5
本文介绍新开发的一种在污水处理中的高科技产品一高效生物膜载体,通过对其在与其他处理方式各方面择比研究过程中的高找到其特点,推广新科技。 相似文献
993.
The challenges faced by coastal protected areas in both promoting highly attractive sites and preserving the natural attributes of these sites have been given a new dimension with the opportunities presented by ecotourism. Realising the market potential of a protected area and, at the same time, conserving the unique features of an area is a difficult task. This paper explores the possibilities that backpacker tourism may offer the Quarantine Station in Sydney Harbour National Park, in Australia. The Quarantine Station is a significant cultural heritage site that is located in a sensitive coastal national park within Sydney's metropolitan area. 相似文献
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Jeremy S. Simmonds Andres Felipe Suarez-Castro April E. Reside James E. M. Watson James R. Allan Scott C. Atkinson Pasquale Borrelli Nigel Dudley Stephen Edwards Richard A. Fuller Edward T. Game Simon Linke Sean L. Maxwell Panos Panagos Philippe Puydarrieux Fabien Quétier Rebecca K. Runting Talitha Santini Laura J. Sonter Martine Maron 《Conservation biology》2023,37(3):e14040
Global efforts to deliver internationally agreed goals to reduce carbon emissions, halt biodiversity loss, and retain essential ecosystem services have been poorly integrated. These goals rely in part on preserving natural (e.g., native, largely unmodified) and seminatural (e.g., low intensity or sustainable human use) forests, woodlands, and grasslands. To show how to unify these goals, we empirically derived spatially explicit, quantitative, area-based targets for the retention of natural and seminatural (e.g., native) terrestrial vegetation worldwide. We used a 250-m-resolution map of natural and seminatural vegetation cover and, from this, selected areas identified under different international agreements as being important for achieving global biodiversity, carbon, soil, and water targets. At least 67 million km2 of Earth's terrestrial vegetation (∼79% of the area of vegetation remaining) required retention to contribute to biodiversity, climate, soil, and freshwater conservation objectives under 4 United Nations’ resolutions. This equates to retaining natural and seminatural vegetation across at least 50% of the total terrestrial (excluding Antarctica) surface of Earth. Retention efforts could contribute to multiple goals simultaneously, especially where natural and seminatural vegetation can be managed to achieve cobenefits for biodiversity, carbon storage, and ecosystem service provision. Such management can and should co-occur and be driven by people who live in and rely on places where natural and sustainably managed vegetation remains in situ and must be complemented by restoration and appropriate management of more human-modified environments if global goals are to be realized. 相似文献
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声光催化是水处理降解有机污染物的一种新技术。在分析中 ,探讨了该技术降解有机污染物的机理 ,以及国内外研究现状 ,包括降解效果和主要的影响因素 相似文献
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城市污泥-猪粪混合堆肥过程中湿度的层次效应及其动态变化 总被引:9,自引:3,他引:6
由城市污泥、猪粪混合堆肥试验表明:升温期堆体各剖面的湿度在50.82%~60.87%之间,高温期在38.7%~52.17%之间;升温期和高温期堆体中湿度的层次效应不明显,堆肥仓门、仓内壁以及堆体深度对湿度层次效应的影响较小;降温期堆体各剖面的湿度在24.54%~49.39%之间,湿度层次效应非常明显,仓门、仓内壁和堆体深度对湿度层次效应产生明显影响;后熟期堆体各剖面的湿度在19.18%~49.34%之间,湿度层次效应相对减弱,仓门和仓内壁是导致湿度层次效应减弱的重要原因.不同堆肥期堆体剖面的湿度差异由大到小为:后熟期>降温期>高温期=升温期,堆体的湿度由大到小为:下部>中部>上部.堆肥过程中湿度随时间的变化满足二级动力学方程. 相似文献