地下水是天然存在的潜在饮用水源,灌溉,农业和工业目的。人口增长以及工业和农业活动的加速发展降低了地下水质量。一个地区的地下水质量由物理和化学参数决定,受地质影响,土壤,土地利用,土地覆盖和人为活动。泰米尔纳德邦的Perambalur区被选为研究区,总地理面积约为1757km2。在研究区,由于在农业用地和采矿活动中使用化肥和农药,地下水质量下降。所以,水文地球化学评估将有助于确定地下水是否适合饮用。在季风前(2021年7月)和季风后季节(2022年1月)从研究区域收集了48个地下水样本。使用美国公共卫生协会规定的pH标准方法分析样品,电导率(EC),总溶解固体(TDS),钙,镁,钠,钾,碳酸盐,碳酸氢盐,氯化物,硫酸盐,硝酸盐和氟化物。使用反距离加权(IDW)插值技术映射主要理化参数的空间分布。从piper地块对水化学相的评估表明,两个季节的主要阳离子和阴离子顺序为Ca2>Mg2>Na>K和Cl->HCO3->SO42->NO3-,分别。Further,该图解释了地下水中永久和暂时硬度的存在。从piper地块对水化学相的评估强调,反向离子交换控制着地下水化学。氯碱指数的评估表明,地下水中的钠和钾被母岩中的镁和钙取代,这决定了地下水的组成。饱和指数值表明方解石和白云石过饱和并趋于沉淀。根据主成分分析,主成分的特征值大于1,在季风前和季风后的总方差中分别占79.8%和79.2%,分别。大多数理化参数,如TDS,EC,Na+,Mg2+,Cl-和SO42-具有很强的正负荷,并负责地下水化学的变化。最后,水质指数的计算发现,与季风前相比,季风后的地下水水质趋于下降。
Groundwater is a naturally occurring potential source for drinking, irrigation, agricultural and industrial purposes. The population growth and accelerated development of industries and agriculture activity degrade groundwater quality. The groundwater quality of an area was determined by the physical and chemical parameters, influenced by geology, soil, land use, land cover and anthropogenic activities. Perambalur district in Tamil Nadu has been selected as a
study area with a total geographical area of around 1757 km2. In the
study area, groundwater quality decreases due to the usage of chemical fertilisers and pesticides in agricultural land and mining activities. So, the hydrogeochemical assessment will help to determine the groundwater suitability for drinking. Forty-eight groundwater samples were collected from the
study area during the pre-monsoon (July 2021) and post-monsoon season (January 2022). Samples were analysed using the standard methods prescribed by the American Public Health Association for pH, electrical conductivity (EC), total dissolved solids (TDS), calcium, magnesium, sodium, potassium, carbonate, bicarbonate, chloride, sulphate, nitrate and fluoride. The spatial distribution of major physiochemical parameters is mapped using the inverse distance weighted (IDW) interpolation technique. The evaluation of hydrochemical facies from piper plots revealed that the major cation and anion were in the order of Ca2+ > Mg2+ > Na+ > K+ and Cl- > HCO3- > SO42- > NO3- in both seasons, respectively. Further, the plot explains the presence of both permanent and temporary hardness in the groundwater. The evaluation of hydrochemical facies from the piper plot emphasises that the reverse ion exchange controls groundwater chemistry. The assessment of chloro-alkaline indices reveals that the sodium and potassium in groundwater get substituted with magnesium and calcium in the parent rock, which determines the groundwater composition. The values of saturation indices reveal that calcite and dolomite are supersaturated and tend to precipitate. From principal component analysis, the principal components have an eigenvalue of more than 1, containing 79.8% and 79.2% in the total variance in pre-monsoon and post-monsoon, respectively. Most physiochemical parameters like TDS, EC, Na+, Mg2+, Cl- and SO42 - have strong positive loading and are responsible for the changes in groundwater chemistry. Finally, the calculation of the water quality index identified that groundwater quality in post-monsoon tends to decline compared to pre-monsoon.