English  |  正體中文  |  简体中文  |  Items with full text/Total items : 28611/40649
Visitors : 643003      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: http://ntour.ntou.edu.tw:8080/ir/handle/987654321/41509

Title: Dissolved iodine species in the East China Sea - a complementary tracer for upwelling water on the shelf
Authors: George T.F. Wong;Chin-Chang Hung;Gwo-Ching Gong
Contributors: 國立臺灣海洋大學:海洋環境化學與生態研究所
Keywords: Iodine;Elemental speciation;Upwelling;East China Sea;Dissolved organic iodine;Oxidation–reduction process
Date: 2004-09
Issue Date: 2017-02-23T03:43:06Z
Publisher: Continental Shelf Research
Abstract: Abstract:Samples were obtained at 26 stations in five cross-shelf transects in the East China Shelf-Sea for the determination of iodate and iodide. The upwelling water at the shelf-edge at 25.5°N was characterized as a dome of subsurface, cold (<18 °C), nitrate-rich (>6 μM), R-iodate-rich (>0.35 μM) and R-iodide-poor (<0.05 μM) water, with iodate/iodide of >5. (R-iodate and R-iodide were the concentrations of iodate and iodide normalized to a salinity of 35.) The upwelling water could be traced farthest away from its source region by the iodine species. They indicate that upwelling occurred at discrete upwelling centers at the shelf edge. Aside from the upwelling center at 25.5°N, a second center was found at 27°N as suggested in recent modeling exercises. Upwelling water was present along the entire length of the outer shelf in the study area from 25°N to 29°N. Its shoreward intrusion across the shelf was more extensive in the southern part of the Shelf-Sea where it reached the middle shelf. At the sea surface, the upwelling water could be detected as a continuous band of water, with low R-iodide (<0.12 μM), high R-iodate (>0.3 μM) and high iodate/iodide (>2.5), which traversed along the entire length of the middle/outer shelf. Thus, the influence of the upwelling water in the Shelf-Sea was more pervasive than what would be construed from the distributions of temperature and nitrate alone.

High surface concentrations of dissolved organic iodine, DOI, were associated with the plume of Changjiang Diluted Water along the Chinese coast. While the changes in the concentrations of iodate in the surface waters could not be accounted for by the reduction of iodate to iodide alone, they could be largely explained when the conversion of iodate to DOI was also allowed.

In box modeling exercises, the geochemical dynamics of the iodine system in the East China Sea Shelf system were qualitatively independent of the magnitude of the transport of the Taiwan Strait Warm Water used. Within the probable range of up to 1 Sv, invariably, iodate was consumed and iodide was produced in the system. The accompanying net export of iodide to the adjoining Kuroshio and the Japan Sea was 1(±0.5)×109 mol/year. Thus, marginal seas may act as a preferred site for the reduction of iodate to iodide and as a net source of iodide to the ocean interior. The production of iodide accounted for only 40(±10)% of the consumption of iodate, suggesting that iodate was converted not only to iodide but also to other forms of iodine in the Shelf system.
Relation: 24(13-14), pp.1465-1484
URI: http://ntour.ntou.edu.tw:8080/ir/handle/987654321/41509
Appears in Collections:[海洋環境與生態研究所] 期刊論文

Files in This Item:

File Description SizeFormat
1-s2.0-S0278434304001402-main.pdf1072KbAdobe PDF59View/Open

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