National Taiwan Ocean University Institutional Repository:Item 987654321/52132
English  |  正體中文  |  简体中文  |  Items with full text/Total items : 28611/40652
Visitors : 754475      Online Users : 41
RC Version 4.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
Scope Adv. Search

Please use this identifier to cite or link to this item:

Title: Classification of Water Masses and Sound-Scattering Layer Biomass in the Waters off Northeastern Taiwan Using a Fuzzy Clustering Method
Authors: 廖正信
Contributors: 國立臺灣海洋大學:環境生物與漁業科學學系
Keywords: fuzzy clustering analysis
sound-scattering layer
volume backscattering strength
water mass
cold eddy
Date: 1999-11
Issue Date: 2019-02-22T01:59:29Z
Publisher: Proc. Natl. Sci. Counc. ROC(B)
Abstract: Abstract: One of the most productive neritic fishing grounds near Taiwan lies to the northeast of the island on the
southeastern margin of the East China Sea continental shelf. In this region, however, the relationships between
biomass distribution and oceanographic conditions are complex and thus difficult to evaluate using traditional sampling methods. The present study, therefore, applied a fuzzy clustering method to hydroacoustic survey data
(Sv, volume backscattering strength indices of biomass) and CTD (conductivity, temperature and depth) observation
data. Four types (A, B, C and D) of water masses were suggested by results of fuzzy clustering analysis. In type
A water mass (continental mixed water), which had high temperature (> 26.54 ºC) and low salinity (< 33.942 psu),
density (< 22.062 kg/m3
) and chlorophyll a fluorescence (< 0.183 mg/m3
), the biomass indices were higher than
–59.37dB. In type D water mass (upwelling of the Kuroshio subsurface water), which had low temperature
(< 23.41 ºC) and high salinity (> 34.272 psu), density (> 23.245 kg/m3
) and chlorophyll a fluorescence (> 0.251
), the biomass indices were less than –65.24 dB, which was about 4 times lower than the biomass value for the
type in A water mass. The biomass indices in water mass types B and C were –62.20 ~ –59.37 dB and –65.24 ~ –62.20
dB, respectively. We conclude that fuzzy clustering is a useful method for classifying the water masses in the waters
off northeastern Taiwan, and that each type of water mass is associated with a particular range of values of the biomass
(Sv) index. Accordingly, application of the hydroacoustic technique and fuzzy clustering analysis to obtain the information about the biomass distribution and water mass types is potentially feasible.
Relation: 23(1) pp.7-18
Appears in Collections:[Department of Environmental Biology and Fisheries Science] Periodical Articles

Files in This Item:

File Description SizeFormat

All items in NTOUR are protected by copyright, with all rights reserved.


著作權政策宣告: 本網站之內容為國立臺灣海洋大學所收錄之機構典藏,無償提供學術研究與公眾教育等公益性使用,請合理使用本網站之內容,以尊重著作權人之權益。
網站維護: 海大圖資處 圖書系統組
DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - Feedback