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161.
《Journal of Natural History》2012,46(1):65-71
Summary Robertgurneya smithi nov. sp. is described and figured from near Adelaide; notes are given on other species (including complete figures of the female of R. ilievecensis Monard), followed by a revised key to the members of this genus, of which R. smithi is the first to be found in Australian waters. 相似文献
162.
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164.
中国西南秋季旱涝的诊断分析 总被引:1,自引:0,他引:1
为了分析中国西南秋季旱涝情况,利用西南地区东部1961~2012年的降水资料和区域旱涝指数对该地区秋季旱涝等级进行了评定,并运用NCEP/NCAR再分析资料与英国气象局海温资料对典型旱涝年的成因进行了探讨。结果表明,西南地区东部降水呈显著减少趋势,并在1990年左右发生了突变。旱年秋季,低层在南中国海附近为显著的气旋性环流异常,西南地区上空存在显著的下沉运动,涝年则相反。进一步分析发现,当西太平洋海温偏高时,可以激发罗斯贝波环流异常,对应在南中国海附近存在异常的气旋性环流,临近的西南地区东部处于异常的下沉气流控制,容易发生干旱,涝年则相反。此外,热带西太平洋海温于20世纪80年代中后期发生了由冷转暖的突变,这与随后西南地区东部秋季降水的突变密切相关。 相似文献
165.
The interdecadal trend and shift of dry/wet over the central part of North China and their relationship to the Pacific Decadal Oscillation (PDO) 总被引:2,自引:0,他引:2
MA ZhuGuo 《科学通报(英文版)》2007,52(15):2130-2139
Based on monthly precipitation and monthly mean surface air temperature (SAT),the dry/wet trends and shift of the central part of North China and their relationship to the Pacific Decadal Oscillation (PDO) from 1951 to 2005 have been analyzed through calculating surface wetness index (SWI). The results indicate that there was a prominent drying trend and an abrupt change in the analysis period. A per-sistent warming period with less precipitation from the mid and late 1970s to present was found,and a shift process exists from the wet to the dry in the central part of North China during 1951-2005. The transition is located in the mid to late 1970s,which should be related to the shift variation of large-scale climate background. The correlation analysis has brought about a finding of significant correlativity between PDO index (PDOI) and SAT,precipitation and SWI in this region. The correlation exhibits that the positive phase of PDOI (warm PDO phase) matches warming,less precipitation and the drought period,and the negative PDOI phase corresponds to low SAT,more precipitation and the wet period. The duration of various phases is more than 25 years. The decadal variation of sea surface temperature (SST) in the North Pacific Ocean is one of the possible causes in forming the decadal dry/wet trend and shift of the central part of North China. 相似文献
166.
用动力学分析和数值计算的方法讨论了大气对热带太平洋几咎典型海温分布构型及其转换过程的热力强迫响应。结果表明:持续的海温热力强迫可以很快地激发出稳定的大气平稳态响应,La Nina(El Nino)期间的大气位势应分别利于夏季西太平洋副高增强(减弱)和位置偏北(偏南)。不同构型的海温转换及转换过程的快慢直接影响大气位势的响应形式,转换过程的异常可能将导致导致夏季西太平洋副高活动异常。 相似文献
167.
《Journal of Natural History》2012,46(2):365-371
A new species of mealybug from southern Asia, Dysmicoccus finitimus sp. nov., is described. It has often been confused with D. cocotis (Maskell), to which it is closely related. Both species are common on coconut and often occur in sufficient numbers to cause growers concern. D. cocotis is known from a wide area of Micronesia, Polynesia and Melanesia, but it is not known to occur west of the Federated States of Micronesia in the north and Fiji in the south. There are no records of D. cocotis from the Solomon Islands or Papua New Guinea, despite extensive collecting on coconut in these territories. D. finitimus is confined to southern India, Sri Lanka, Cocos (Keeling) Islands and peninsular Malaysia. There are no records yet of the new species from Indonesia. 相似文献
168.
《Journal of Natural History》2012,46(9):1329-1336
The beach hoppers Megalorchestia californiana and M. corniculata (Crustacea: Talitridae) were studied for the interaction of two of their epibionts. Rhabditid nematodes reside under the host's dorsal pereonites where they may be facultative parasites or feed on bacteria and detritus associated with the host. The mite Thinoseius brevisternalis (Canaris, 1962) (Acari: Eviphididae) preys upon the above nematodes. Both nematodes and mites also use the host as transport between patches of beach wrack. Other epibiotic Acari on talitrids are also reported here. 相似文献
169.
《Journal of Natural History》2012,46(3):719-729
The Lepidoptera faunas of the remote Pacific islands, Easter, Pitcairn and Henderson, are listed and discussed, with notes on biology. They are compared with the faunas of Mururoa and Rapa Islands, the five islands providing contrasts in geology, ecology and human disturbance. A new hawk moth is described, Hippotion hateleyi, endemic to Henderson Island. 相似文献
170.