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21.
《Journal of Natural History》2012,46(35-36):2219-2234
Brazil is a tropical country and has the greatest anuran species richness in the world: the Atlantic Forest has roughly half of these species. We contribute to the knowledge of the anurans of the Brazilian Atlantic Plateau, determining the composition of anuran fauna associated with leaf litter in six landscapes, patterns of spatial distribution and levels of similarity among these landscapes and other communities. The sampling by pitfall traps was conducted in São Paulo state, at a total of 68 sites distributed among continuous and fragmented landscapes. The anuran fauna of these sites is typical of dense ombrophilous forest, and the composition resembled those of other localities of the Atlantic Forest. A cluster analysis comparing the six landscapes resulted in three main groups (Caucaia + Reserva do Morro Grande; Tapiraí + Ribeirão Grande; Fazenda Paraíso + Parque Estadual Jurupará). In the cluster analysis comparing these faunas to those of other localities, we could not find an effect of geographic distance on the differences in composition among areas.  相似文献   
22.
The gray-headed tody-flycatcher Todirostrum poliocephalum is a passerine endemic to the Atlantic Forest of Brazil. We describe the nest and nesting behaviour of this species and investigate geographical variation in breeding traits in the genus using data from the literature, museum collections, and citizen science projects. We located 21 nests of the gray-headed tody-flycatcher, 13 of which we monitored. Nest height above the ground averaged 3.3 ± 3.4 m (n = 21). Nests were built over a 16.8 ± 5.6-day period (n = 6) by both adults. Clutch sizes ranged from two to three eggs, with a mean of 2.9 ± 0.3 eggs (n = 10). Eggs measured 16.6 ± 0.5 × 12.0 ± 0.5 mm (n = 23) and weighed 1.1 ± 0.1 g (n = 19). Mean incubation period was 17 days (n = 3) and mean nestling period was 15.5 days (n = 2). Apparent reproductive success was 30.8%, with predation being the primary cause of nest failure (46.1%). Mayfield’s reproductive success was 25.9%, and daily survival rates for eggs and nestlings were 0.957 and 0.971, respectively. Clutch sizes increased with latitude, but temperature and precipitation seasonality had very low importance in explaining clutch size variation.  相似文献   
23.
The deep-sea asellote isopod species belonging to the family Haploniscidae were studied from three study sites off the North Carolina coast and one off Bermuda. The following five new species, belonging to the new genus Chandraniscus, are described: C. kussakini from Alpha-A off Bermuda (1300 m), C. eastwardae, C. costlowi and C. chardyi from the Carolina lower slope site Beta and C. negoescuae at site Sigma on the Carolina continental rise (4910 m). Three new species of Haploniscus are described: H. kensleyi from the Carolina upper continental slope at Alpha-B, H. gnanamuthi from site Alpha-A off Bermuda, H. harrietae from site Beta. A new species Chauliodoniscus wilsoni from site Sigma is also described. Three new species of the genus Hydroniscus, found in this alpha-taxonomic study, include H. buzwilsoni and H. malyutinae from site Beta and H. watlingi from both Beta and Sigma. Two new species of the genus Antennuloniscus, A. menziesi and A. lincolni, are described from site Beta over the Carolina lower continental slope.  相似文献   
24.
The male, female, pupa and larva of a new species of Gelechiidae (Lepidoptera), Locharcha opportuna Moreira and Becker, are described and illustrated with the aid of optical and scanning electron microscopy. A preliminary analysis of mitochondrial DNA sequences including members of related lineages is also provided. The immature stages are associated with galls induced by a species of Palaeomystella Fletcher (Lepidoptera: Momphidae) on Tibouchina sellowiana (Cham.) Cogn. (Melastomataceae), endemic to the Atlantic Rainforest. Larvae are kleptoparasitic, usurping the gall internal space and thereafter feeding on the internal tissues. By determining the variation in population density of both species and following gall development individually throughout ontogeny under field conditions, we demonstrated that the kleptoparasite completes its life cycle inside galls induced by Palaeomystella, where pupation occurs. The variation in seasonal abundance of the kleptoparasite is tied to that of the cecidogenous species, with their corresponding peaks in density occurring sequentially.

http://zoobank.org/urn:lsid:zoobank.org:pub:525F6D52-8CE1-47D1-A0D9-78B564DF5565  相似文献   
25.
2008年1月-2009年3月西南大西洋公海滑柔鱼资源探捕调查期间,对阿根廷滑柔鱼钓捕技术进行了研究。结果表明:3种不同类型的钓钩钓捕效率有所不同,在渔况一般时,白天韩产软质钓钩的上钩率比国产钓钩高25.22%,而在夜间,国产钓钩的上钩率比韩产软质钓钩高46.26%;韩产硬质钓钩的上钩率在白天和夜间均高于国产钓钩,尤其在夜间,硬质钓钩的上钩率比国产钓钩高40.00%以上;在上钩率较高时,3种钓钩的上钩率差别不明显。6种不同颜色国产钓钩的上钩率有所不同,放钓水深较浅时,深色钓钩的上钩率均高于浅色钓钩,而放钓水深较深时,浅色钓钩的上钩率多高于深色钓钩。在鱼况一般或较差时,菱形卷扬机钓捕效率高于圆形卷扬机,而在产量较高的3-5月份渔汛期间,上钩率较高时,两种卷扬机钓捕效率相差不大。不同位置钓机的钓捕效率有所不同,其中船中位置最高。  相似文献   
26.
27.
《Journal of Natural History》2012,46(9-12):567-596
This work is the third publication on the new amphipod species collected from the Azores Triple junction zone by the cruises ATOS, DIVA 2, MARVEL, PICO and SEAHMA 1. Seven new species and a new genus are described belonging to six families, Eusiridae, Leucothoidae, Oedicerotidae, Phoxocephalidae, Pleustidae, and Podoceridae. They were sampled in four sites, Menez Gwen, Lucky Strike, Saldanha and Rainbow.  相似文献   
28.
In July 2013, the Jianghuai–Jiangnan region of China experienced a persistent extreme high temperature,and the surface air temperature(SAT) over many areas of the region set a new record, which had a profound impact on people's lives. This study explored the possible mechanism for this extreme climate phenomenon. The results show that the sea surface temperature(SST) over the midNorth Atlantic in July 2013 was the warmest observed over the past 160 years. The strong anomaly of the SST connects to the East Asian upper level westerly and western Pacific subtropical high(WPSH) via the teleconnection wave train and further contributes to the SAT variability over the Jianghuai–Jiangnan region; this connection could be one possible mechanism for the formation of the recordbreaking extreme hot event(EHE) over the Jianghuai–Jiangnan region in July 2013. In addition, for the EHE over the Jianghuai–Jiangnan region, the role of the WPSH was generally emphasised. This study found that the variability of the upper level westerly over the Jianghuai–Jiangnan region is also an important climate factor impacting the SAT of the region. In particular, the record-breaking weakness of the upper level westerly corresponded to the record-breaking SAT over the Jianghuai–Jiangnan region in July 2013. These results indicate that the role of the upper level westerly should be emphasised in addition to the WPSH, according to both the variability in the summer air temperature and the EHE over the Jianghuai–Jiangnan region.  相似文献   
29.
The spatial shift of the North Atlantic Oscillation (NAO) is analyzed by using the Twentieth Century Reanalysis version 2 dataset and identifying NAO action centers directly on winter mean sealevel pressure (SLP) anomaly maps. The spatial shift of the NAO is characterized by four NAO spatial shift indices: the zonal and meridional shifts of the NAO southern and northern action centers. It is found that the zonal and meridional shift trends of the NAO action centers move along a path of southwest-northwest direction. Spectral analysis shows that the four NAO spatial shift indices have periodicity of 2-6 years and the NAO index has periodicity of 2-3 years in terms of high-frequency variations. On a decadal time scale, the NAO spatial shift indices are closely (positively) related to the NAO index, which is in agreement with previous studies of the relationship between the NAO index and the spatial shift of the NAO pattern. However, there is no relationship between the NAO index and the meridional shift of the northern action center on an interannual time scale. The significant relationship between the NAO index and the interannual variability of NAO spatial shift indices is very likely to be associated with synopticscale Rossby wave breaking, which generates surface pressure anomalies and thus affects the phase and pattern of the NAO. The correlations of winter westerly winds over 90°W-0° and the NAO index and the NAO spatial shift indices have a ’+ - + -’ structure from the Equator to the North Pole. Although there is close correlation between the NAO spatial shift indices and the strength of the zonal winds in the North Atlantic region, the effect of the zonal winds on the NAO spatial shift differs at different latitudes. Hence, the role of the zonal winds is probably a result of the NAO spatial shifts.  相似文献   
30.
利用耦合地球系统模式(CESM1.0),通过对比有青藏高原的控制试验和无青藏高原的敏感性试验,定性地分析青藏高原对不同季节北大西洋深水(NADW)形成的影响机制.研究结果表明,青藏高原对NADW形成的影响机制因季节而异.移除青藏高原后,NADW形成将会减弱,冷季(北半球10月—次年3月)NADW形成的显著减弱是由海洋表...  相似文献   
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