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Given the key role of biogenic volatile organic compounds(VOCs) to tropospheric chemistry and regional air quality, it is important to generate accurateVOCs emission inventories. However, only a less fraction of plant species, in temperate grassland of Inner Mongolia, has been characterized by quantitative measurements. A taxonomic methodology, which assigns VOCs measurements to unmeasured species, is an applicable and inexpensive alternation for extensive VOCs emission survey, although data are needed for additional plant families and genera to further validate the taxonomic approach in grassland vegetation. In this experiment, VOCs emission rates of 178 plant species were measured with a portable photoionization detector( PID). The results showed the most of genera and some families have consistent feature of their VOCs emission, especially for isoprene, and provide the basic premise of taxonomic methodology to develop VOCs emission inventories for temperate grassland. Then, the taxonomic methodology was introduced into assigning emission rate to other 96 species, which no measured emission rates available here. A systematical emission inventory of temperate grassland vegetation in Inner Mongolia was provided and further evidence that taxonomy relationship can serve as a useful guide for generalizing the emissions behavior of many, but not all, plant families and genera to grassland vegetation. 相似文献
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There are numerous reports of invertebrates that are visual mimics of ants, but no formal reports of mimicry of an ant, by
an ant. Two endemic Australian ants, Myrmecia fulvipes and Camponotus bendigensis are remarkably similar in colour and size; both are generally black but have red legs and golden gasters. The density and
hue of the pubescence of each ant's gaster are relatively uncommon in ants, but are very rare when combined with the black
forebody and red legs. The ants are similarly sized but are smaller than other species closely related to M. fulvipes. The range of C. bendigensis lies entirely within that of M. fulvipes, and both species excavate ground nests in open woodland. Finally, workers of both species are crepuscular and forage solitarily.
These data suggest that the relatively benign formicine C. bendigensis is a Batesian mimic of the formidable myrmeciine M. fulvipes.
Received: 9 August 1999 / Accepted in revised form: 22 December 1999 相似文献
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室内培养底栖端足类日本大螯蜚饵料研究 总被引:1,自引:0,他引:1
本文在实验条件下探讨了5种饵料对海洋底栖端足类日本大螯蜚的培养效果。实验指标为存活率,生长速度,日增长率和发育状况。结果表明,青岛大扁藻与新月菱形藻1:1混合液的培养效果最佳,合成饲料是较好的补充饵料,螺旋藻粉不宜作为日本大螯蜚的培养饵料。动物性饵料培养效果不如植物性饵料,但对日本大螯蜚的早期快速成长具有一定的促进作用。 相似文献