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Rising atmospheric carbon dioxide (CO2) concentration is expected to change plant tissue quality with important implications for plant–insect interactions. Taking advantage of canopy access by a crane and long‐term CO2 enrichment (530 μ mol mol?1) of a natural old‐growth forest (web‐free air carbon dioxide enrichment), we studied the responses of a generalist insect herbivore feeding in the canopy of tall trees. We found that relative growth rates (RGR) of gypsy moth (Lymantria dispar) were reduced by 30% in larvae fed on high CO2‐exposed Quercus petraea, but increased by 29% when fed on high CO2‐grown Carpinus betulus compared with control trees at ambient CO2 (370 μ mol mol?1). In Fagus sylvatica, there was a nonsignificant trend for reduced RGR under elevated CO2. Tree species‐specific changes in starch to nitrogen ratio, water, and the concentrations of proteins, condensed and hydrolyzable tannins in response to elevated CO2 were identified to correlate with altered RGR of gypsy moth larvae. Our data suggest that rising atmospheric CO2 will have strong species‐specific effects on leaf chemical composition of canopy trees in natural forests leading to contrasting responses of herbivores such as those reported here. A future change in host tree preference seems likely with far‐ranging consequences for forest community dynamics. 相似文献
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C. BUDDE 《Bioacoustics.》2013,22(2-3):191-201
ABSTRACT This paper presents the acoustic features and the behavioural context of the unison call of the East African Crowned Crane Balearica regulorum gibbericeps. It speculates on the different functions of the unison call according to the situations where it is given. This is tested with the appeasement-threat hypothesis, which claims that the threatening acoustic characteristics of the unison call should be enhanced if it is given as a territorial call. In comparison, the appeasing acoustic characteristics should be stronger if the unison call is performed at flock sites where it possibly serves for mate assessment. 相似文献
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Tipula (Pterelachisus) recondita Pilipenko & Salmela, sp. n. is described. The new species is collected from two localities: Finland, Kittilä (North boreal ecoregion) and Russia, Primorski kray (Zone of temperate broadleaf and mixed forests). Although variation in the structure of male hypopygium between the Finnish and Russian populations is observed, DNA barcode sequences differ only by three nucleotides (0.2 % K2P distance), supporting presence of one widespread species. K2P minimum distances between the new species and 17 other species of the subgenus range from 5.3 to 15.8 % (mean 8.8 %). The new species is forest-dwelling, known from an old-growth herb-rich forest (Finland) and Quercus mongolica forest (Russia). The new species is perhaps closest to Tipula (Pterelachisus) imitator Alexander and in lesser extent to Tipula (Pterelachisus) pauli Mannheims; the inner gonostylus of both species are illustrated. 相似文献
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扎龙自然保护区丹顶鹤(Grus japonensis)巢的内分布型及巢域 总被引:4,自引:0,他引:4
为了探讨丹顶鹤繁殖种群的空间分布,2002~2006年的4~5月份,在黑龙江扎龙国家级自然保护区,采用定点观察法、无样地取样法、GPS定位等研究方法和分布距离指数、最近邻体法等衡量指标对丹顶鹤(Grus japonensis)巢的内分布型及巢域进行了研究.结果表明:(1)扎龙保护区丹顶鹤巢的内分布型,I2002=2.140>2,I2003=2.048>2,I2004=2.093>2, I2006=3.263>2,均为聚集分布;(2)在假设扎龙保护区丹顶鹤巢域面积等于领域面积、巢域形状为圆形且所有个体面积大小相等的前提下,丹顶鹤的巢域为(0.510±0.019)km2,年度间有所差异,分别为2002年(0.542±0.257)km2、2003年(0.569±0.067)km2、2004年(0.557±0.054)km2、2006年(0.344±0.119)km2.分析表明,丹顶鹤对于栖息生境的整体分布和繁殖微生境质量的变化具有一定适应和应答的能力.为了更有效地验证本文的研究结果并对丹顶鹤进行保护,还有待于长期监测并进一步研究. 相似文献
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繁殖期内丹顶鹤的日常短鸣声行为模式分析 总被引:2,自引:1,他引:1
繁殖期内,丹顶鹤(Grus japonensis)的日常短鸣声行为具有一定的模式。本文通过行为的实时观察,并利用MATLAB分析软件对日常短鸣声进行了计算机声谱分析,给出了鸣声模式的声图、示波图和频谱。结果表明:雄性的鸣声特性是每个单次叫声中含有的音节数较少,一般不超过4个音节;而雌性的鸣声特性是每个单次叫声中含有的音节数较多,最少的含有4个音节。雌雄鸣声的共同特性是每个音节都是由三个声脉冲组成。l号鹤的谐和特性较好,2号音色较纯净;雌性鸣肌速率较高,雄性则较低。自由选择配对组配偶间音质是一纯一杂,而人为组合组雌雄音质相同。 相似文献
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我国内蒙古发现白鹤夏季群体 总被引:7,自引:1,他引:6
白鹤 (Grusleucogeranus)又名西伯利亚鹤、黑袖鹤。体长 1 3 5cm ,站高 1 40cm。体羽除初级飞羽外 ,皆为白色。全世界野生白鹤数量不足 40 0 0只 ,已经被IUCN红皮书列为全球濒危种类 ,CITES列入附录Ⅰ ,我国也将白鹤列为国家一级重点保护鸟类。据文献记载及现有资料证明 ,白鹤在我国为旅鸟和冬候鸟。 2 0 0 2~ 2 0 0 4年夏季在内蒙古图牧吉国家级自然保护区均记录到白鹤夏季种群 ,数量为 8只、7只和1 6只。这是我国首次记录到白鹤夏季集群。笔者对白鹤夏季行为及食性进行了初步观察。 相似文献
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