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野外观鸟是一项比较高雅的时尚休闲活动,它源于西方国家,已经有了几十年历史。我国观鸟活动兴起仅有数年之久,但其发展速度和势头却令世人瞩目。每逢节假日,人们经常可见观鸟人三五结伴,漫步郊野,用望远镜细细搜寻、辨认、欣赏鸟类。更有近乎痴狂的观鸟独行侠,他们唯观鸟是乐,长途跋涉,遍访祖国名山大川,追寻飞羽的踪迹。在这些活跃的观 相似文献
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在广州番禺仲元实验中学的观鸟社有一群快乐的“鸟人”,5年来,在指导老师卜标的带领下,他们足迹遍布国内外,“追鸟”行程达20万里,练就了一身听音辨鸟、见影识鸟的好本事。梦回九连山九连山位于广东与江西的交界,横跨广东江西两省,是南岭的余脉。在九连山21300公顷的土地上,山峦连绵起伏,地貌复杂,森林植被茂密,古木参天,生物资源极为丰富,为我国中亚热带与南亚热带过渡区森林生态系统最丰富的地区。这里不但是东亚植物区系的发源地之一,也是一些古老植物种属著名的“避难所”。九连山因有斑头大翠鸟、海南璃而盛名, 相似文献
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在2005年春天来临之际,改版扩刊后的《江苏环境科技》与读者见面了。它倾注了广大读者的热情支持和悉心关爱,借此机会我谨向所有支持它的作者、专家和广大读者,表示衷心的感谢! 相似文献
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记者在赴法国采访Pollutec2004之前,对这趟遥远的旅行做了一番设计,既然出国采访也不是轻而易举之事,何不让它更丰富多彩一些,也算不虚此行吧!此外,由于工作关系,记者对一些外国,特别是法国企业有些接触,于是在出行之前联系了两家与能源有关的企业,以便在“正事”办完后,顺便再多做两个采访。在与其中一家企业——法国德地氏热力技术公司驻北京代表处了解有关情况,特别是当听说其公司总部工厂,一个生产企业居然位于一片原始森林中时,更是引起了记者极大的兴趣和好奇心。 相似文献
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<正>科罗拉多河是世界上一条河中大坝最多的河。大河从美国北方的高山森林中流出,经过美国的7个州,再经墨西哥两个州后入海。这里曾是美洲狮子统治的领地。过去两百年来人们用大坝改造了河流,创造了自己的幸福和财富。在很久的时间里,很少有人意识到科罗拉多河伟大的另一 相似文献
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“山林若是没有鸟,明媚风光长不了,鸟是害虫的天敌。鸟是生态之仪表。”家乡的山很多,林子也很大;林子大了,就什么鸟都有。我每次回去,都能受到它们的热烈欢迎,真是“山鸟多情如识我”。 相似文献
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在全球环保领域,世界观察研究所(WORLDWATCH INSTITUTE)可谓“声名显赫”,这不仅是因为它创办时间早, 涌现过几位世界级环境名人。更重要的是,世界观察研究所及其所发表的研究报告和大量出版物在全球学术界都享有很高声望,它们影响了世界各国环保技术的发展和有关政策的制定, 甚至也左右了联合国等国际机构和一些国家大政方针的出台, 可以说世界观察研究所在环境及相关领域都起到了“绿色”风向标的作用。 相似文献
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The Canary Islands are home to a guild of endemic, threatened bird-pollinated plants. Previous work has suggested that these
plants evolved floral traits as adaptations to pollination by flower specialist sunbirds, but subsequently, they appear to
have co-opted generalist passerine birds as sub-optimal pollinators. To test this idea, we carried out a quantitative study
of the pollination biology of three of the bird-pollinated plants, Canarina canariensis (Campanulaceae), Isoplexis canariensis (Veronicaceae) and Lotus berthelotii (Fabaceae), on the island of Tenerife. Using colour vision models, we predicted the detectability of flowers to bird and
bee pollinators. We measured pollinator visitation rates, nectar standing crops as well as seed-set and pollen removal and
deposition. These data showed that the plants are effectively pollinated by non-flower specialist passerine birds that only
occasionally visit flowers. The large nectar standing crops and extended flower longevities (>10 days) of Canarina and Isoplexis suggests that they have evolved a bird pollination system that effectively exploits these low frequency non-specialist pollen
vectors and is in no way sub-optimal. Seed set in two of the three species was high and was significantly reduced or zero
in flowers where pollinator access was restricted. In L. berthelotii, however, no fruit set was observed, probably because the plants were self-incompatible horticultural clones of a single
genet. We also show that, while all three species are easily detectable for birds, the orange Canarina and the red Lotus (but less so the yellow-orange Isoplexis) should be difficult to detect for insect pollinators without specialised red receptors, such as bumblebees. Contrary to
expectations if we accept that the flowers are primarily adapted to sunbird pollination, the chiffchaff (Phylloscopus canariensis) was an effective pollinator of these species. 相似文献
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