The Kali River is a significant source of surface water as well as the main tributary of River Hindon that flows through major cities of western Uttar Pradesh, India. It flows throughout the urban and industrial regions; hence, it carries various amounts of pollutant. Therefore, a study was conducted to examine spatial–temporal variations in river water quality by determining physicochemical variables and heavy metal concentrations at seventeen sampling stations (S₁–S₁₇) throughout the river stretch. Various physicochemical variables, namely pH, EC, TDS, turbidity, BOD, COD, TH, TA, Ca, Mg, Na, K, HCO₃⁻, Cl⁻, SO₄²⁻, NO₃⁻, and PO₄³⁻ were higher in summer than in winter. The order of mean metal concentrations was Fe > Pb > Mn > Ni > Zn > Cu > Cr > Cd. The relationships among measured physicochemical variables and pollution index were examined. Furthermore, multivariate statistical methods were used to assess spatial–temporal variation in water quality to identify current pollution sources and validate results. Water quality index and comprehensive pollution index indicated that the Kali River was less polluted from S₁ to S₈. However, downstream sampling sites were polluted. Pollution starts from S₉ and drastically increases at and beyond S₁₃ because of effluents from industries and sugar mills in Muzaffarnagar. The study suggests cleaning the downstream region of river to restore human health and flora and fauna in the river ecosystem.

中文翻译：

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通过多元统计方法在印度北方邦卡里河评估水质的时空变化。

卡利河是重要的地表水源，也是流经印度北方邦西部主要城市的兴登河的主要支流。它流向整个城市和工业区；因此，它携带各种污染物。因此，进行了一项研究，通过确定整个河段十七个采样站（S ₁ –S ₁₇）的理化变量和重金属浓度来检查河水水质的时空变化。各种物理化学变量，即pH值，EC，TDS，浊度，BOD，COD，TH，TA，钙，镁，钠，钾，HCO ₃ ^- ，氯^-，SO ₄ ^2-，NO ₃ ^-和PO ₄夏季³⁻高于冬季。平均金属浓度的顺序为：Fe> Pb> Mn> Ni> Zn> Cu> Cr> Cd。检查了所测量的理化变量与污染指数之间的关系。此外，多变量统计方法用于评估水质的时空变化，以识别当前的污染源并验证结果。水质指数和综合污染指数表明，从S ₁到S ₈污染较少。但是，下游采样点被污染了。污染从S ₉开始，并在S ₁₃及以后急剧增加因为来自穆扎法尔纳格尔的工业和糖厂的废水。研究建议清洁河流下游区域，以恢复河流生态系统中的人类健康和动植物。