Magnetic signature of the iron-bearing minerals archived in sediments is sensitive to change in environment and therefore, studied to reconstruct the signals linked with environmental processes. In the present work, we have analyzed 11 sediment cores from Vembanad lagoon, southwest coast of India, to estimate the magnetic fluctuations associated with environmental processes. Down-core variation in magnetic susceptibility and anhysteretic, isothermal and saturation isothermal remnant magnetization and S and H-ratios have been interpreted to map the degree and spatial distribution of anthropogenic pollution in and around the lagoon. Downcore variation of magnetic susceptibility of Vembanad lagoon sediments varies from 10 to 100 × 10⁻⁸ m³/ kg. The top layers of sediment samples from river mouth regions (Periyar and Muvattupuzha rivers) show higher susceptibility values and incidentally these samples are of coarse sized. The subtle variations in SIRM/χ_lf ratios suggest that there are magnetic grain size differences in the samples. The SIRM and χ_lf relation suggests that dominant magnetic grain size in sediments. The low ARM/χ_lf ratios suggest a relatively higher ferrimagnetic contribution and coarser magnetite grain size. Rock magnetism data reveal that the coarse magnetic grain size is affecting the pollution of Vembanad lagoon. We also analyzed downcore variability of metal concentrations such as Fe, Mn, Cu, Zn, Ni and Cr, and all these metals exhibit higher concentrations in the top layers of the cores. Our study suggests that higher values of magnetic parameters and metal concentrations are due to various anthropogenic sources.

沉积物中沉积的含铁矿物的磁特征对环境变化敏感，因此，人们对其进行了研究以重建与环境过程有关的信号。在目前的工作中，我们分析了印度西南海岸文巴纳德泻湖的11个沉积物核，以估算与环境过程有关的磁涨落。磁化率和磁滞，等温和饱和等温残余磁化强度以及S和H比率的磁芯下变已被解释为制图了泻湖内和周围人为污染的程度和空间分布。文巴纳德泻湖沉积物磁化率的下层变化范围从10到100×10 ^-8  m ³/ 公斤。来自河口地区（佩里亚尔河和Muvattupuzha河）的沉积物样品的顶层显示出较高的磁化率值，并且附带地，这些样品的尺寸较大。SIRM / _χlf比值的细微变化表明样品中存在磁性晶粒尺寸差异。SIRM和_χlf关系表明，沉积物中占主导地位的磁性晶粒尺寸。低ARM / _χlf比率表明，亚铁磁性贡献相对较高，磁铁矿晶粒尺寸较大。岩石磁性数据表明，粗大的磁性晶粒尺寸正在影响Vembanad泻湖的污染。我们还分析了诸如Fe，Mn，Cu，Zn，Ni和Cr等金属浓度的下限变异性，所有这些金属在芯层的顶层均表现出较高的浓度。我们的研究表明，较高的磁参数值和金属浓度是由于各种人为来源引起的。