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61.
A collection of brachiopods by the Institute of Oceanology, Academia Sinica (Qingdao), contains eight species from seven genera.
Six of the species have been recorded previously from China seas—Lingula adamsi, L. anatina, Discinisca stella, Pelagodiscus atlanticus, Campages mariae, Terebratalia coreanica. Two species (Terebratulina hataiana andFrenulina sanguinolenta) have been described from other parts of the Pacific area. The apparent absence of any endemic species is a noteworthy feature
of Chinese in comparison with Japanese faunas. 相似文献
62.
Artificial light at night: implications for early life stages development in four temperate freshwater fish species 总被引:1,自引:0,他引:1
Anika Brüning Franz Hölker Christian Wolter 《Aquatic Sciences - Research Across Boundaries》2011,73(1):143-152
Flora and fauna have both evolved under a natural cycle of light and dark. But especially in urban areas, the night is now
increasingly disturbed by artificial light. Many traits and behaviours in fish are triggered by a circadian clock, for example
hatching and swim bladder inflation, which predominantly take place at dusk or night. As lighting becomes brighter and extends
farther into rural areas, the distinction between day and night becomes increasingly blurred. Therefore, the loss of diurnal
trigger by artificial light at night was hypothesized having deleterious effects on these traits and impact fish reproduction.
To assess these effects, eggs of four native freshwater fishes, Eurasian perch Perca fluviatilis, roach Rutilus rutilus, bleak Alburnus alburnus and chub Leuciscus cephalus, were incubated under two different light conditions: a photoperiod of 14 h light:10 h darkness (LD) and continuous illumination
(LL). The time to hatch and swim bladder inflation was recorded. The species showed inconsistent reactions to the light treatments.
In roach and bleak, the time to 50% hatch was longer in LL, whereas continuous lighting had an accelerating effect in chub.
Incubation in LL elongated the hatching period in perch and roach and, in perch, the onset of darkness seemed to trigger hatching.
The swim bladder inflation was significantly promoted by continuous light in chub and bleak but was not affected in roach.
In conclusion, nocturnal artificial illumination could have an effect on hatching and initial swim bladder filling by masking
the day–night-change and thereby diminish the trigger effect. However, the reactions were species specific and the increase
in variation indicated a lack of diurnal triggering, whilst a general deleterious effect of artificial light at night has
not been identified on early life stages. 相似文献
63.
V. G. Eselevich V. M. Bogod I. V. Chashey M. V. Eselevich Yu. I. Yermolaev 《Geomagnetism and Aeronomy》2009,49(1):133-135
The solar sources of the magnetic storms of November 8 and 10, 2004, are analyzed. The preliminary results of such an analysis [Yermolaev et al., 2005] are critically compared with the results of the paper [Tsurutani et al., 2008], where solar flares were put in correspondence with these magnetic storms. The method for determining solar sources that cause powerful magnetospheric storms is analyzed. It has been indicated that an optimal approach consists in considering coronal mass ejections (CMEs) as storm sources and accompanying flares as additional information about the location of CME origination. 相似文献
64.
I. B. Safarov 《Izvestiya Physics of the Solid Earth》2006,42(3):260-270
The elastic and density properties of rocks of the Shamakha-Ismailly seismogenic blocks are studied by the ultrasonic pulse method in quasi-hydrostatic high pressure apparatuses. An attempt is made to more accurately determine the upper crustal lithology of these blocks. The observed values of the elastic and density characteristics of the rocks at high pressures suggest that the upper layers in the Ismailly and Shamakha blocks can consist of sedimentary carbonate rocks such as marls, sandstones, mudstones, and limestones. The middle layers apparently consist of volcaniclastic rocks: lithoclastic tuffs, andesites, etc. The lower layer (basement) in both blocks is likely composed of basic rocks such as basalts, trachybasalts, etc. According to the values of elastic wave velocities and densities, gabbroid rocks may compose the fourth layer of the Buinuz intrusion, identified from seismic data. 相似文献
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69.
Chashei I. V. Lebedeva T. O. Tyul’bashev S. A. Subaev I. A. 《Astronomy Reports》2021,65(11):1150-1169
Astronomy Reports - A joint analysis of the monitoring data of interplanetary scintillations with solar and geophysical data showed that at the descending phase of the 24 solar activity cycle, the... 相似文献
70.
V. M. Zobin E. I. Gordeev V. F. Bakhtiarov E. I. Ivanova Yu. M. Khatkevich V. N. Khodenko V. E. Levin V. P. Mityakin 《Natural Hazards》1992,6(1):51-70
The earthquake of 6 October 1987 (M = 6.6), which occurred near the Shipunsky Cape, Kamchatka, was the largest crustal event in the vicinity of the main city of Kamchatka — Petropavlovsk-Kamchatsky — during the last three decades. It was followed by numerous aftershocks. This earthquake allowed us to test the effectiveness of the seismic hazard monitoring in Kamchatka, including the seismological, geodetic and hydrogeochemical surveys. The seismic survey provided the location and source nature of the main shock and aftershocks and the seismic environment of the main shock. The geodetic and hydrogeochemical surveys have yielded data on the response to earthquakes of the Earth's surface deformations, water level, and chemical elements concentration in the underground water. As a result, the following data were obtained: The earthquake of 6 October had a seismic moment 4–10 E18 Nm, thrust type of faulting and the source volume of 20 × 20 × 10 km3. The maximum intensity was VI–VII (MSK-64 scale) and maximum acceleration 88 cm/s2. Before this event, a relative increase in the number of the upper mantle (depth more than 100 km) moderate magnitude earthquakes during 5 years and a one-year period of seismic quiescence for small shallow earthquakes, were recognized. Significant anomalies in HCO3 and H3BO3 concentrations in the underground waters were observed in the wells a week before the main shock. 相似文献