頁籤選單縮合
題 名 | In Situ and Ex Situ Target Strength Measurement of Mesopelagic Lanternfish, Diaphus Theta (Family Myctophidae) |
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作 者 | Sawada, Kouichi; Uchikawa, Kazuhisa; Matsuura, Tomohiko; Sugisaki, Hiroya; Amakasu, Kazuo; Abe, Koki; | 書刊名 | Journal of Marine Science and Technology |
卷 期 | 19:3 2011.06[民100.06] |
頁 次 | 頁302-311 |
分類號 | 351.95 |
關鍵詞 | In situ target strength; Diaphus theta; J-QUESTχ; Swimbladder; Spheroid model; |
語 文 | 英文(English) |
英文摘要 | Acoustic target strengths (TS) of myctophid fish Diaphus theta were measured in situ at 70 kHz off the east coast of Hokkaido by tethering an acoustic-optical system (the Japanese Quantitative Echosounder and Stereo-video Camera System or J-QUESTχ) at a depth of 150 m from a research vessel. Fish length distributions were obtained from daytime hauls taken with a frame trawl after the TS measurement. Measured average TS (<TS>) and a standard length (SL) in cm gave the empirical length - average TS relationship, <TS> = 20logSL-70.6, assuming that the linear TS is proportional to the square of the SL. A laboratory TS measurement and theoretical modeling of D. theta support the estimated length - average TS relationship. |
本系統中英文摘要資訊取自各篇刊載內容。