东山湾水体和沉积物中有机碳的春夏季分布特征

Distribution characteristics of total organic carbon in seawater and surface sediments of Dongshan Bay during the spring and summer

为了解东山湾水体和沉积物中有机碳的分布特征、影响因子及其污染状况,研究分析了TOC的含量分布特征,并讨论了TOC与叶绿素a、盐度、化学需氧量、重金属及粒度等环境因子之间的关系。结果表明,东山湾水体中TOC的浓度范围为1.24～2.33 mg·L-1,平均值为1.78 mg·L-1。其浓度的分布特征呈湾内高于湾外的格局;春季东山湾水体中TOC浓度高于夏季;表底层水体中TOC浓度变化不明显。沉积物中有机碳含量的变化范围为0.02%～0.78%。其含量的分布趋势呈现湾中部高湾口低的格局。东山湾水体中有机碳与叶绿素a及COD值之间呈显著正相关关系,与盐度值之间呈负相关关系。沉积物中有机碳与粘土及重金属(Hg、Cu、Zn和Cr)含量之间呈显著正相关关系。

Concentrations of total organic carbon （TOC） were determined in seawater and surface sediments during the spring and summer from 12 sites in the Dongshan Bay. The results indicated that the distributions of TOC in seawater in spring and summer decreased from inner bay to out - bay. The TOC content in seawater was higher in spring than in summer. Concentrations of TOC were lower in sediments from the mouth of the bay relative to inner the bay. Concentrations of TOC in seawater showed significant positive correlation with chlorophyll a and COD, and negative correlation with salinity. Significantly positive correlation was also found between TOC with clay and heavy metals （Hg, Cu, Zn, and Cr） contents.