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61.
Middle Eocene–early Oligocene ostracode faunal changes in northwestern Kyushu of southwestern Japan are identified in this study. Ostracodes occur from shelf deposits of five formations: the middle Eocene Okinoshima, the upper Eocene Funazu, the uppermost Eocene–lowermost Oligocene Kishima, the lowermost Oligocene Itanoura, and the lower Oligocene Waita Formations. The middle Eocene–earliest Oligocene ostracodes were characterized by warm-water genera, indicating tropical, subtropical and Tethyan genera, whereas the late early Oligocene ostracodes do not include warm-water taxa, consisting of temperate realm genera. The middle Eocene–earliest Oligocene ostracodes do not include remarkable changes of species composition, in contract with equatorial Pacific radiolarians and West Coast USA molluscs. Ostracodes suggest that distinct climatic cooling did not occur in the southwestern Japan during the middle Eocene–earliest Oligocene.  相似文献   
62.
The projected increase of atmospheric CO2 concentration ([CO2]) is expected to increase rice yield, but little is known of the effects of [CO2] at low temperature, which is the major constraint to growing rice in cool climates. We grew rice under two levels of [CO2] (ambient and elevated by 200 μmol mol?1) and two nitrogen (N) fertilization regimes in northern Japan in 2003 (cool weather) and 2004 (warm weather) in the field in a free‐air CO2 enrichment (FACE) system. Elevated [CO2] significantly increased grain yield in both years in both N regimes, but the magnitude of the increase differed between years: 6% in 2003 vs. 17% in 2004, with a significant interaction between [CO2] and year. This difference resulted from responses of spikelet number and ripening percentage to elevated [CO2]. Enhancement of dry matter production and N uptake at heading by elevated [CO2] was smaller in 2003 than in 2004, although at maturity there was no difference between years. No significant interaction between N regime and [CO2] was detected in yield and yield components. The results suggest that yield gain due to elevated [CO2] can be reduced by low temperature.  相似文献   
63.
We fitted Northern Pintail Anas acuta in Japan with satellite transmitters and monitored their spring migration movements relative to locations where the highly pathogenic H5N1 avian influenza virus was detected in Whooper Swans Cygnus cygnus in 2008. Pintails were assumed not to be infected with the H5N1 virus at the time they were marked because capture occurred between 2 and 5 months before reported outbreaks of the virus in Japan. We assessed spatial and temporal overlap between marked birds and occurrence of the virus and tracked Pintails after they departed outbreak locations. Eight of 66 (12.1%) Northern Pintails marked with satellite transmitters used wetlands in Japan where the H5N1 virus was detected in Whooper Swans. Apparent survival did not differ between Pintails that used H5N1 sites and those that did not. However, the proportion of Pintails that migrated from Japan was significantly lower among birds that used H5N1 sites compared with those that did not (0.50 vs. 0.79). Northern Pintails were present at the H5N1 sites from 1 to 88 days, with five birds present at the sites from 0 to 7 days prior to detection of the virus in Swans. The six Pintails observed to depart H5N1 sites did so within 2–77 days of the reported outbreaks and moved between 6 and 1200 km within 4 days of departure. Four Pintails migrated to eastern Russia. After their departure from outbreak sites, Northern Pintails made long‐distance migrations within the period when newly infected ducks would shed the H5N1 virus. This supports a hypothesized mechanism by which a highly pathogenic avian influenza virus could be spread by migratory birds.  相似文献   
64.
YAMAGUCHI  T.; STREET  H. E. 《Annals of botany》1977,41(6):1129-1133
Excised root cultures of soya bean cultured at 30 °C inWhite's medium (1943) supplemented with 0•1 per cent yeastextract have been serially sub-cultured over 13 culture passagesof 7 days although a decline in the linear growth and lateralformation begins in the third passage and the roots are devoidof laterals from the 8th passage onwards. Applications of abscisicacid within the concentration range 0•01–0•001mg l–1 and during the first two culture passages enhancedthe linear growth of the main axis, the number of emergent lateralsand the total length of laterals. This effect has been shownfor two cultivars, with roots derived from seed in both itsfirst and second year of storage and under different conditionsof culture and culture pH.  相似文献   
65.
Supplement: coprophagy in leporids and other mammalian herbivores   总被引:1,自引:0,他引:1  
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