| 摘要: |
| 于1993年5月和1994年3－4月通过调查，用硫离子选择电极法研究南沙群岛海域泻湖及礁外沉积物间隙水中的∑S（－Ⅱ）及SO42-，探讨泻湖内及礁外间隙水中-2价硫的分布特征，沉积物-海水界面间硫的扩散转移通量和-2价硫的热力学平衡控制体系。结果表明，该海区∑S（－Ⅱ）含量，泻湖间隙水中远比礁外高，人为活动剧烈的礁内泻湖高于人为活动少的泻湖，离礁近的礁外间隙水中的高于远离礁的间隙水中的。在礁外沉积物间隙水中-2价硫含量呈垂向增加的趋势，沉积物-海水界面间HS-，S2-均是从沉积物向上覆海水扩散，SO42-反之。礁内泻湖的扩散量远高于礁外的，HS-扩散总平均为61.34 μmol/(m2*d)，SO42-为-0.41 mmol/(m2*d)；礁外泻湖的HS-总平均为14.96 μmol/(m2*d)，SO42-为-0.35 mmol/(m2*d)。该海区的-2价硫主要由S＋2e→S2-氧化还原电对控制，平衡时Eh计算值与实测值接近，单质疏作为亚稳态可存在于沉积物中，并可与溶解铁继续形成自生黄铁矿（FeS2）沉淀。 |
| 关键词: –2价硫 间隙水 扩散通量 -2价硫的控制体系 南沙群岛海域泻湖 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金资助项目，49576291号 |
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| –2 VALENCE SULFUR OF LAGOON AND OFF – REEF SEDIMENT INTERSTITIAL WATERS OF NANSHA ISLANDS, SOUTH CHINA SEA |
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Song Jinming, Li Pengcheng
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Institute of Oceanology, Chinese Academy of sciences, Qingdao 266071
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| Abstract: |
| –2 valence sulfur and sulfate of lagoon and off -reef sediment interstitial waters of Nansha Islands, South China Sea, were studied for the first time in May, 1993 and in March and April, 1994 by using exploration, including distribution characteristics of -2 valence sulfur of interstitial waters in lagoon and off -reef sediments, diffusion fluxes across sediment-water interface and thermodynamic equilibrimn system of -2 valence sulfur. The main results were as follows:
Concentrations in lagoon interstitial waters were much higher than those in off reef sediment interstitial waters. Concentrations in interstitial waters in the lagoons with human activity were much higher than that those in interstitial waters in lagoons without human activity, and in near-reef sediment interstitial waters were much higher than those in off -reef sediment interstitial waters. Concentrations tended to increase with depth of off - reef sediment interstitial waters. HS- and S2- diffused from sediment to overlying seawater, but it was opposite for SO42-. The diffusion flux in the lagoon was higher than that off -reef. The average diffusion flux of HS- in the lagoons was 61.34 μmol/(m2*d) and was -0.41 μmol/(m2*d) for SO42-. The average diffusion flux of HS- off -reef sediments was 14.96 μmol/(m2*d) and -0.35μmol/(m2*d) for SO42-. -2 valence sulfur was controlled by the S+2e –> S2- redox pair in sediment interstitial waters of the water region of Nansha Islands. The Eh values calculated from the redox pair corresponded to the measured Eh values. Sulfur as substable form can exist in sediments, and induce pyrite (FeS2) precipitation. |
| Key words: –2 valence sulfur, Interstitial water, Diffusion flux, Controlling system of -2 valence sulfur, Water region of Nansha Islands |
