Srinivas Reji, Shynu R, Sreeraj M K, Ramachandran K K
ESSO-National Centre for Earth Science Studies, Akkulam, Thiruvananthapuram, India.
ESSO-National Centre for Earth Science Studies, Akkulam, Thiruvananthapuram, India.
Mar Pollut Bull. 2017 Jul 15;120(1-2):370-375. doi: 10.1016/j.marpolbul.2017.05.028. Epub 2017 May 19.
Metal concentrations (Al, Cr, Ni, Cu, Zn, and Pb), grain size, and total organic carbon content in 29 surface sediment samples from the nearshore area off Calicut were analyzed to determine their distribution and pollution status. Surface sediments were dominantly silts with low percentage of clay and sand at nearshore and offshore areas. The mean metal concentrations were in the following order: Cr>Ni>Zn>Pb>Cu. The enrichment factor and geo-accumulation index of metals suggest that the surface sediments were not polluted by Zn and moderately polluted by Cu and Ni. By contrast, Cr and Pb showed significant enrichment levels. Results from a multivariate statistical analysis suggested that the spatial enrichment of these heavy metals was related to sediment type. Thus, the sediment distribution and their metal enrichment were mainly controlled by local hydrodynamic conditions that caused the winnowing of fine-grained sediments.
分析了科泽科德近海29个表层沉积物样本中的金属浓度（铝、铬、镍、铜、锌和铅）、粒度和总有机碳含量，以确定它们的分布和污染状况。近岸和近海区域的表层沉积物主要是粉砂，粘土和砂的含量较低。金属平均浓度顺序如下：铬>镍>锌>铅>铜。金属的富集因子和地累积指数表明，表层沉积物未受锌污染，铜和镍受到中度污染。相比之下，铬和铅显示出显著的富集水平。多变量统计分析结果表明，这些重金属的空间富集与沉积物类型有关。因此，沉积物分布及其金属富集主要受当地水动力条件控制，这些条件导致细粒沉积物被簸选。
