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101.
102.
???ú????????????????????????????????2001??3??~2006??7????????????????Satoβ????????????????????????????????β??????(20 s??30 s??40 s)??QC?,????????QC????????????? 35.8 f 0.95??46.0 f 0.94 ??59.4 f 0.93 ??Q0?????????????????????????????????????????????,?о?????Q0???????????QC???????????????????????????????? 相似文献
103.
Micro-communities are supposed to have more potential functions of biodegradation of polysaccharides than single strain; however, the intestinal micro-communities involved in the biodegradation of Enteromorpha polysaccharides (EP) were seldom reported. In order to obtain the EP-degrading micro-community, the intestines of Siganus oramin was obtained to isolate the micro-communities, which were enriched by 0.3% of EP as the sole carbon source. A stable micro-community with EP degradative capability was achieved after seven generations of subculture, named H1. Results showed that H1 was able to degrade 75% of EP within 24 hours, and the activity of EP lyases reached 500 U mL?1 in 32 hours. With denaturing gradient gel electrophoresis (DGGE) and 16S rRNA gene clone library analysis, ten bacteria closely related to Marinomonas pontica, Microbacterium sp., Leucobacter chironomi, Cyclobacterium sp., Algoriphagus winogradskyi, Pseudoalteromonas sp. and Vibrio sp. were determined. Furthermore, compared with the DGGE bands sequence and the clone library analysis, the dominant bacteria of the EP-biodegrading micro- community were Pseudoalteromonas sp. and Vibrio sp., with the respective proportion of 38% and 46%, and they should play an important role in EP degradation together with other degrading bacteria in the micro-community H1. 相似文献
104.
Yan Taiming Hu Jiaxiang Cai Yueping Xiong Sen Yang Shiyong Wang Xiongyan He Zhi 《中国海洋湖沼学报》2017,35(5):1197-1204
Laboratory-reared Schizothorax davidi larvae and juveniles were examined to assess the formation and characteristics of David’s schizothoracin otoliths.Otolith development was observed and their formation period was verifi ed by monitoring larvae and juveniles of knownage.The results revealed that lapilli and sagittae developed before hatching,and the first otolith increment was identified at 2 days post hatching in both.The shape of lapilli was relatively stable during development compared with that of sagittae;however,growth of four sagittae and lapilli areas was consistent,but the posterior area grew faster than the anterior area and the ventral surface grew faster than the dorsal surface.Similarly,the sum length of the radius of the anterior and posterior areas on sagittae and lapilli were linearly and binomially related to total fish length,respectively.Moreover,daily deposition rates were validated by monitoring knownage larvae and juveniles.The increase in lapilli width was 1.88±0.080 0μm at the ninth increment,which reached a maximum and the decreased gradually toward the otolith edge,whereas that of sagittae increased more slowly.These results illustrate the developmental biology of S.davidi,which will aid in population conservation and fish stock management. 相似文献
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近年来随着北极冰盖的融化,北极通航已成为可能,而白令海峡作为北极航道重要的出口/入口,其战略地位也将逐步显现并被各国关注。在讨论白令海峡的治理与合作时,首先要明确白令海峡是用于国际航行的海峡,而作为海峡沿岸国的美国和俄罗斯对于白令海峡的管控与合作将成为影响未来北极航行的重要因素。为同时保障海峡沿岸国与使用国的利益,可借鉴马六甲海峡的治理经验,在现有治理机制的基础上进一步深化海峡沿岸国与海峡使用国的合作机制。中国作为海峡使用国也有必要积极参与白令海峡的合作治理。 相似文献
107.
Implications of diverse sedimentation patterns in Hala Lake, Qinghai Province, China for reconstructing Late Quaternary climate 总被引:2,自引:0,他引:2
Bernd Wünnemann Johannes Wagner Yongzhan Zhang Dada Yan Rong Wang Yan Shen Xiaoyu Fang Jiawu Zhang 《Journal of Paleolimnology》2012,48(4):725-749
Hala Lake is located in the Qilian Mountains, Qinghai Province, China, at 4,078?m a.s.l. Its sediments contain an archive of climate and hydrologic changes during the Late Quaternary, as it is located close to the area influenced by the East-Asian summer monsoon and westerly-driven air masses. Sedimentation patterns and depositional conditions within the lake were investigated using eight sediment cores from different water depths, and this information was used to evaluate the feasibility of using a single core to reconstruct past climate and hydrological conditions. Long core H7, from the center of the lake (65?m water depth) and core H8 from a western, near-shore location (20?m water depth), were compared in detail using sediment composition and geochemical data (X-ray fluorescence, loss-on-ignition and CNS analysis). Age models were constructed using 17 AMS radiocarbon dates and indicate negligible reservoir error for sediments from the lake center and?~1,000?year errors for the near-shore sediment core. Cores H1?CH5 and HHLS21-1 revealed a sediment succession from sand and silty clay to laminated clay on the southern side of the lake. Undisturbed, finely laminated sediments were found at water depths???15?m. Core H5 (2.5?m long), from 31?m water depth, yielded abundant green algal mats mixed with clayey lake deposits and was difficult to interpret. Algae occurred between 25 and 32?m water depth and influenced the dissolved oxygen content of the stratified lake. Comparison of cores H7 and H8 yielded prominent mismatches for different time periods, which may, in part, be attributed to internal lacustrine processes, independent of climate influence. We thus conclude that data from a single sediment core may lead to different climate inferences. Common shifts among proxy data, however, showed that major climate shifts, of regional to global significance, can be tracked and allow reconstruction of lake level changes over the last 24,000?years. Results indicate advance of glaciers into the lake basin during the LGM, at which time the lake experienced lowest levels, 25?C50?m below present stage. Stepwise refilling began at ca. 16 kyr BP and reached the ?25?m level during the B?lling/Aller?d warm phase, ca. 13.5 kyr BP. A desiccation episode falls within the Younger Dryas, followed by a substantial lake level rise during the first millennium of the Holocene, a result of climate warming, which promoted glacier melt. By ca. 7.6 kyr BP, the lake reached a stable high stand similar to the present level, which persisted until ca. 6 kyr BP. Disturbed sediments in core H7 indicate a single mass flow that was most likely triggered by a major seismic event?~8.5 kyr BP. Subsequent lake development remains unclear as a consequence of data mismatches, but may indicate a general trend to deteriorating conditions and lake level lowstands at ca. 5.0?C4.2, 2.0 and 0.5 kyr BP. 相似文献
108.
109.
110.
水下地形测量高程异常点剔除方法研究 总被引:2,自引:0,他引:2
本文针对水下地形测量过程中测深数据的粗差问题,结合在生产工作中的一些经验和有关的资料,提出了测深数据处理的方法,并编写了相应的程序用于生产。 相似文献