Environmental Chemistry Laboratory, Resource Management and Environment Section, Life Science Division, Institute of Advanced Study in Science and Technology, Guwahati, 781035, Assam, India.
Department of Environmental Science, Gauhati University, Guwahati, 781014, Assam, India.
Environ Pollut. 2019 Jul;250:969-980. doi: 10.1016/j.envpol.2019.04.112. Epub 2019 Apr 26.
The sediment characterisation of wetlands belonging to the Northeastern Region of India particularly regarding the assessment of sediment carbon stock is very scanty. The presently available literature on the wetlands cannot be employed as a common model for managing the wetlands of the Northeastern Region of India as wetlands are a sensitive ecosystem with a different origin or endogenous interventions. Thereby, this research was conducted on Deepor Beel for investigating the spatial and seasonal variation of sediment parameters, the relationship between the parameters and pollution status of the wetland. Results revealed that the study area is of an acidic nature with a sandy clay loam type texture. Organic carbon, total nitrogen and available nitrogen were higher in sediments in the monsoon period. The mean stock of the sediment carbon pool of Deepor Beel is estimated to be 2.5 ± 0.7 kg m. The average non-residual fraction percentage (63.2%) of Pb was higher than the residual fraction. Zn content ∼490 mg kg exceeding its effect range medium (ERM) was determined to suggest frequent biological adverse effects. Highest metal enrichment factor (EF) values were shown by Zn and Pb, which ranged between 78 and 255. Risk assessment code (RAC) values of Pb between 21 and 29% indicated its high bio-accessibility risk. Pearson's coefficient matrix revealed a low degree of positive correlation between organic carbon content and metal concentration. Principal component analysis revealed that the first component comprising of EC, basic cations and metals accounted for 62.3% of variance while the second component (OM, OC, TN, AN, AP) and the third component (pH) accounted for 21.8% and 7.0% of the variance, respectively. The present study revealed the adverse impact of human inputs on the Deepor Beel quality status.
印度东北部地区湿地的沉积物特征，特别是关于沉积物碳储量的评估，非常匮乏。目前关于湿地的可用文献不能作为管理印度东北部地区湿地的通用模式，因为湿地是一个具有不同起源或内生干预的敏感生态系统。因此，本研究在 Deepor Beel 进行，以调查沉积物参数的空间和季节性变化，以及参数与湿地污染状况之间的关系。结果表明，研究区域呈酸性，质地为砂质粘壤土。有机碳、总氮和有效氮在季风期的沉积物中含量较高。Deepor Beel 沉积物碳库的平均储量估计为 2.5±0.7 kg/m。非残留部分（63.2%）的 Pb 含量高于残留部分。Zn 含量约为 490 mg/kg，超过其效应范围中值（ERM），表明经常发生生物不良反应。Zn 和 Pb 的最高金属富集因子（EF）值在 78 至 255 之间。Pb 的风险评估代码（RAC）值在 21%至 29%之间，表明其具有较高的生物可利用性风险。Pearson 系数矩阵显示有机碳含量与金属浓度之间存在低度正相关。主成分分析显示，由 EC、碱性阳离子和金属组成的第一成分占方差的 62.3%，而第二成分（OM、OC、TN、AN、AP）和第三成分（pH）分别占方差的 21.8%和 7.0%。本研究揭示了人为输入对 Deepor Beel 质量状况的不利影响。
