Department of Environmental Science, Central University of South Bihar, Gaya, India.
School of Environmental Sciences, JNU, New Delhi, India.
Environ Sci Pollut Res Int. 2021 Apr;28(15):18686-18701. doi: 10.1007/s11356-020-11775-z. Epub 2021 Jan 6.
The concentration of trace metals Mn, Pb, Ni, Zn, and Cu in the core sediment from Kabar Tal wetland was analyzed to understand the level of contamination in the vertical profile. Additionally, total organic carbon (TOC) and available phosphorus (AP) were also analyzed to infer the biogeochemistry of trace metals and the correlation that exists among them. Five core sediments were collected at the end of the monsoon season from different locations in the study area, representing diverse anthropogenic and agricultural activities. The average concentration of trace metals in sediments followed the order Mn > Pb > Ni > Zn > Cu. The trace metal concentration in the surface sediments was higher and decreased with depth in the vertical profile. Contamination factor (CF), geoaccumulation index (Igeo), enrichment factor (EF), and pollution load index (PLI) were used to evaluate sediment quality and the pollution status of the lake sediments. Cu, Zn, and Ni showed minor to moderate enrichment, and Pb showed a severe level of enrichment in all the core sediment samples. However, the sediment quality guidelines' index indicates that the sediments are moderately polluted with copper, zinc, and nickel and severely polluted with lead. There exists a strong positive correlation among Pb-Ni, Ni-AP, and AP-Pb, and a strong negative correlation among TOC-Ni, TOC-Pb, and TOC-AP for all the sediment samples. Additionally, the principal component analysis (PCA) and cluster analysis (CA) suggest that a good similarity exists among Pb, Ni, and Zn. The study indicates that trace metals in wetland sediments have originated from multiple anthropogenic sources like agricultural runoff (fertilizers), direct addition of solid wastes, discharge of untreated wastewater, and long-range transport from the oil refinery in the wetland.
卡巴尔塔尔湿地核心沉积物中痕量金属 Mn、Pb、Ni、Zn 和 Cu 的浓度进行了分析，以了解垂直剖面中的污染水平。此外，还分析了总有机碳 (TOC) 和有效磷 (AP)，以推断痕量金属的生物地球化学特征以及它们之间的相关性。在季风季节末期，从研究区域的不同位置采集了 5 个核心沉积物，代表了不同的人为和农业活动。沉积物中痕量金属的平均浓度顺序为 Mn > Pb > Ni > Zn > Cu。表层沉积物中的痕量金属浓度较高，在垂直剖面中随深度的增加而降低。污染因子 (CF)、地质累积指数 (Igeo)、富集因子 (EF) 和污染负荷指数 (PLI) 用于评估沉积物质量和湖泊沉积物的污染状况。Cu、Zn 和 Ni 表现出轻微到中度富集，而 Pb 在所有核心沉积物样品中表现出严重富集。然而，沉积物质量指南指数表明，沉积物受到铜、锌和镍的中度污染，以及铅的严重污染。在所有沉积物样本中，Pb-Ni、Ni-AP 和 AP-Pb 之间存在强烈的正相关，而 TOC-Ni、TOC-Pb 和 TOC-AP 之间存在强烈的负相关。此外，主成分分析 (PCA) 和聚类分析 (CA) 表明 Pb、Ni 和 Zn 之间存在良好的相似性。该研究表明，湿地沉积物中的痕量金属来源于多种人为来源，如农业径流 (肥料)、固体废物的直接添加、未经处理的废水排放以及炼油厂的远距离运输。
