Rainfall duration and debris-flow initiated studies for real-time monitoring   总被引：9，自引：0，他引：9  

Chen Chien-Yuan  Chen Tien-Chien  Yu Fan-Chieh  Yu Wen-Hui  Tseng Chun-Chieh 《Environmental Geology》2005,47(5):715-724

A rainfall-induced debris flow warning is implemented employing real-time rain gauge data. The pre-warning for the time of landslide triggering derives the threshold or critical rainfall from historical events involving regional rainfall patterns and geological conditions. In cases of debris flow, the time taken cumulative runoff, to yield abundant water for debris triggering, is an important index that needs monitoring. In gathered historical cases, rainfall time history data from the nearest rain gauge stations to debris-flow sites connected to debris flow are used to define relationships between the rainfall intensity and duration. The effects by which the regional rainfall patterns (antecedent rainfall, duration, intensity, cumulative rainfall) and geological settings combine together to trigger a debris-flow are analyzed for real-time monitoring. The analyses focused on 61 historical hazard events with the timing of debris flow initiation and rainfall duration to burst debris-flow characteristics recorded. A combination of averaged rainfall intensity and duration is a more practical index for debris-flow monitoring than critical or threshold rainfall intensity. Because, the outburst timing of debris flows correlates closely to the peak hourly rainfall and the forecasting of peak hourly rainfall reached in a meteorological event could be a valuable index for real-time debris-flow warning.  相似文献   

Characterization of lattice strain induced by neutron irradiation   总被引：1，自引：0，他引：1  

Hsin-Yi Tseng  Peter J. Heaney  T. C. Onstott 《Physics and Chemistry of Minerals》1995,22(6):399-405

Powder X-ray diffraction and Rietveld refinement have been used to study structural damage induced by neutron irradiation of orthoclase (Or₉₄) from Benson Mines, New York. X-ray diffraction profiles of samples exposed to total neutron doses in excess of 6.3×10¹⁸ n/ cm² exhibit small but measurable peak broadening in comparison with unirradiated orthoclase. Rietveld structure refinements and transmission electron microscope observations indicate that the X-ray peak broadening arises primarily from the effect of strain rather than particle size. The results reveal a positive correlation between the neutron dose and the anisotropic strain percentage calculated from the Lorentzian profile parameters. This strain-induced broadening probably stems from numerous point defects created by recoiling atoms during neutron collisions. These observations have important implications for the diffusive behavior of ³⁹Ar and ⁴⁰Ar.  相似文献   

胶州湾口内海水中叶绿素浓度的周年变化和垂直分布   总被引：7，自引：2，他引：7  

潘友联  郭玉洁  曾呈奎 《海洋与湖沼》1995,26(1):21-27

于１９８３年１１月－１９８５年１１月在胶州湾两个观测站逐月进行了２周年的海水中叶绿素浓度的定点研究。结果表明，（１）胶州湾口表层海水中的叶绿素α平均浓度为３．０５（１．０２－１５．６２）ｍｇ／ｍ＾３；真光层中平均为２６．３４（９．９７－１０６．５９）ｍｇ／ｍ＾２；其季节变化呈春（３－４月）、秋（９－１１月）双峰型。（２）小型（＜７８μｍ）的浮游植物平均占海水中叶绿素α的８５．７６％。（３）叶绿素ａ  相似文献   

中国海洋红藻——御前凹顶藻Laurencia Omaezakiana Masuda的形态与结构特征     

丁兰平  黄冰心  曾呈奎 《海洋科学集刊》2006,47(47):169-175

凹顶藻类是近年来海洋红藻分类学研究的主要热点之一(Garbary et al.，1998；Nam et al.，2000；Nam et al.，2001；Masuda et al.，1996， 1998a，2001)。从经典分类学方面来说，这个类群不仅形态学差异大，而且解剖学特征也存在许多需要进一步探讨的问题，难度较大，所以长期以来其系统并不是十分明确。Saito(1967)提出的凹顶藻两亚属的分类系统应该说在当时是比较先进的。各国的藻类学家对此意见比较一致(张峻甫等1985；McDermid 1988)， 虽然有些修改或补充(张峻甫等1985；Furnari et al.，1993；Gil-Rodrigeuz et al.，1993)，但Nam(1990)对此提出了不同意见，他认为营养性生长轴产生的围轴细胞数目比其他分类特征更稳定，因此建议修改凹顶藻类的系统鉴定特征。Nam等(1994)认为凹顶藻属应该划分成两个属:凹顶藻属和拟凹顶藻属Osmundea Stackhouse。随后，Garbary等(1998)认为新的凹顶藻属应该再划分成两个属:凹顶藻属及软骨凹顶藻属Chondrophycus。目前，早期的凹顶藻属被划分成了3个属：凹顶藻属、软骨凹顶藻属及拟凹顶藻属。作者赞同后者的观点。 长期以来，中国凹顶藻类的研究在海藻分类学中是比较薄弱的一个方面，除了Tseng(1943)、张峻甫等(1980，1985)对香港和西沙群岛有过较详细研究外，其他的都比较简略。而随着国际上凹顶藻研究的不断深入，中国于1998年也开始了中国凹顶藻类的系统研究工作。目前作者发现仅在黄渤海分布着一个凹顶藻新记录种，即御前凹顶藻Laurencia omaezakiana Masuda。根据最新的凹顶藻类分类系统，此种仍然属于凹顶藻属。由于凹顶藻属物种含有丰富的次生代谢物质，因此，作为海藻化学研究的热点物种之一，有必要对其进行详细的介绍。  相似文献   

藻类分子生物技术两年评──基因工程及其上游──分子遗传学   总被引：8，自引：1，他引：8  

秦松  严小军  曾呈奎 《海洋与湖沼》1996,27(1):103-111

根据１９９２年１月－１９９４年６月国内外发表资料，评述藻类分子遗传学和基因工程领域的最新进展。认为：两年来藻类分子遗传学发展迅速，经济藻类基因工程研究已经有所突破。藻类学研究正在进入分子时代，分子生物技术成为推动藻类学研究和藻类资源开发的新动力。  相似文献   

悬浮生长的条斑紫菜膨大藻丝无性系的培养及产生壳孢子的研究初报   总被引：4，自引：0，他引：4  

孙爱淑  曾呈奎 《海洋与湖沼》1996,27(6):667-669

１９９０年以来，采用多因子正交试验方法，对悬浮生长的条斑紫菜膨大藻丝即孢子囊技生长发育规律进行研究。通过细胞工程方法，建立悬浮培养的膨大藻丝无性系，并使该无性系长年大量繁殖。经过对膨大藻丝的生长发育调控，可使膨大藻丝适时，大量放散壳孢子。  相似文献   

Application of artificial neural networks in typhoon surge forecasting   总被引：1，自引：0，他引：1  

C.M. Tseng  C.D. Jan  J.S. Wang  C.M. Wang 《Ocean Engineering》2007,34(11-12):1757-1768

A typhoon-surge forecasting model was developed with a back-propagation neural network (BPN) in the present paper. The typhoon's characteristics, local meteorological conditions and typhoon surges at a considered tidal station at time t−1 and t were used as input data of the model to forecast typhoon surges at the following time. For the selection of a better forecasting model, four models (Models A–D) were tested and compared under the different composition of the above-mentioned input factors. A general evaluation index that is a composition of four performance indexes was proposed to evaluate the model's overall performance. The result of typhoon-surge forecasting was classified into five grades: A (excellent), B (good), C (fair), D (poor) and E (bad), according to the value of the general evaluation index. Sixteen typhoon events and their corresponding typhoon surges and local meteorological conditions at Ken–fang Tidal Station in the coast of north-eastern Taiwan between 1993 and 2000 were collected, 12 of them were used in model's calibration while the other four were used in model's verification. The analysis of typhoon-surge forecasting results at Ken–fang tidal station show that the Model D composing 18 input factors has better performance, and that it is a suitable BPN-based model in typhoon-surge forecasting. The Model D was also applied to typhoon-surge forecasting at Cheng-kung Tidal Station in south-eastern coast of Taiwan and at Tung-shih Tidal Station in the coast of south-western Taiwan. Results show that the application of Model D in typhoon-surge forecasting at Cheng-kung Tidal Station has better performance than that at Tung-shih Tidal Station.  相似文献   

西沙群岛网地藻科的研究     

陆保仁  曾呈奎 《海洋科学集刊》1985,(24):69-86

西沙群岛的网地藻科。迄今只见樊恭炬等在“金银岛及其附近几个岛礁的海藻名录”一文中报道5种,该文中的暗黑圈扇藻 Zonaria nigrescens Sonder实际上是匍扇藻 Lobophora variegate (Lamx.) Womersley的同物异名,应予撤销。因此,有效记录只是4种,即:叉开网地藻 Dictyota divaricata Lamx,脆弱网地藻 Dictyota friabilis Setch,南方团扇藻 Padina australis Hauck 和匍扇藻。 我们研究了中国科学院海洋研究所1957-1980年先后五次对西沙群岛进行海洋植物区系调查时采得的大量网地藻科标本,在本文报道12种其中有一个新种:西沙团扇藻 Padina xishaensis sp.nov,七种新记录:匍匐网翼藻 Dictyopteris repens (Okam.) Boerg.，鹿角网地藻 Dictyota cervicornis Kuetz.,刺叉网地藻 D. patens J.Ag,波利团扇藻 Padina boryana Thivy.,小团扇藻 P. minor Yamada,琼斯团扇藻 P. jonesii Tsuda和棕叶藻 Stypopodium zonale (Lamx.) Papenfuss。其中鹿角网地藻、琼氏团扇藻和棕叶藻是中国新记录。 研究用的标本,包括新种的模式标本都存于中国科学院海洋研究所植物标本室。  相似文献   

中国马尾藻属的研究 Ⅶ.宾德种群的三个新种     

曾呈奎  陆保仁 《海洋与湖沼》1996,27(1):23-28

在研究中国真马尾藻亚属SubgenusSargassum刺托组SectionAcanthocarpicae团徽托序亚组SubsectionGlomerulatae宾德系SeriesBinderiana宾德种群SpeciesGroupBinderia过程中，发现该种群新种3个，它们是中间马尾藻SargassumIntermediumTsengetLusp．nov.，模式标本于1975年5月15日由李伟新采自广西涸洲岛，模式标本号AST75－0594；琼海马尾藻SargassumqionghaienseTsengetLusp．nov，模式标本于1983年7月12日由陆保仁采自海南省琼海县沙，模式标本号CA83－0016；裂开马尾藻SargasumerumensTsengetLusp．nov，模式标本于1982年4月23日由陆探仁采自海南省三亚市鹿回头，模式标本号AST82－0413。模式标本均存于中国科学院海洋研究所植物标本室。  相似文献   

用基因枪将GUS基因导入褐藻细胞中表达   总被引：18，自引：2，他引：18  

秦松  张健  李文斌  王希华  童顺  孙勇如  曾呈奎 《海洋与湖沼》1994,25(4):353-356

于１９９３年１１月－１９９４年２月，用高压氦气式基因枪，将ＰＨ１２２１质粒装有ＧａＭＶ ３５Ｓ启动子，ＧＵＳ基因以及ｎｏｓ的３＇调控区导入海带和裙带菜组织切块中。４８ｈ后，在海带假根细胞和裙带菜中肋部叶片细胞中检测到ＧＵＳ基因的表达。实验表明，微粒子轰击法是外源基因导入大型褐藻的一个有效途径。ＧａＭＶ ３５Ｓ启动子能够驱动外源基因在海洋藻类中的表达，可作为藻类基因工程的启动元件。  相似文献