| 摘要: |
| 采用0.1 mol/L HCl和1% Na2CO3两步连续提取法, 对103个渤海表层沉积物样品的生物硅含量进行了分析, 结果表明, 渤海表层沉积物中生物硅含量范围为7.3～54.7 g/kg, 均值31.5 g/kg, 高于其他相关调查, 原因可能是由于采用0.1 mol/L HCl提取过程中, 破坏了生物硅表面的金属氧化膜。对沉积物生物硅含量的空间分布表征显示, 莱州湾是沉积物生物硅的低值区、而渤海湾与辽东湾之间的河北沿岸海域是相对高值区, 初步认为是陆源营养物质的输入与黄河泥沙长期不断输入干扰沉积环境的稳定性, 造成了该海域表层沉积物生物硅分布差异。主成分分析显示, 生物硅含量与沉积物黏粒含量、细粉砂、有机氮、有机碳的含量均呈极显著正相关(P<0.01), 进一步证实沉积物粒度特征和营养环境对生物硅积累的影响。 |
| 关键词: 生物硅 分步提取 表层沉积物 渤海 |
| DOI：10.11759/hykx20160917002 |
| 分类号: |
| 基金项目:中国科学院重点部署项目(KZZD-EW-14); 中国科学院战略先导专项(XDA11020402) |
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| Biogenic silica in the surface sediment of the Bohai Sea |
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DAI Zhen-fei,XUE Yong,ZHANG Hai-bo,TU Chen,LUO Yong-ming
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| Abstract: |
| The 103-surface sediment samples collected from the Bohai Sea were extracted by 0.1 mol/LHCl and 1% Na2CO3 sequentially for the analysis of biogenic silica. The results showed that biogenic silica contents were in the range of 7.3～54.7 g/kg, with an average of 31.5 g/kg. The measured contents of the biogenic silica were higher than other reported values in the same study area. This might be the result of different extraction methods that were employed in the studies, the extraction by 0.1 mol/L HCl may dissolve the oxides plaque coated on the biogenic silica in the sediment and therefore increase the release of the biogenic silica. Spatial distributions of the biogenic silica were characterized using geographic information system (GIS) and the spatial heterogeneity of the biogenic silica was observed in the surface sediments of the Bohai Sea. The highest content located along the coastal marine of Hebei province, in contrast to the lowest content located in the Laizhou Bay. This suggested long-term terrestrial input of nutrient substances and frequent disturbance by the input of the Yellow River sediments may govern the abundance and distribution of biogenic silica in this area. Principal component analysis indicated the contents of biogenic silica had a significantly (P < 0.01) positive correlation with the contents of clay, fine sand, total organic nitrogen, and organic carbon in the sediment of the Bohai Sea, which further confirmed the effects of grain size and nutrient substance on the accumulation of biogenic silica in the sediment. |
| Key words: Biogenic silica Sequential extraction Surface Sediment Bohai sea |
