Hydrochemistry, sources of ions, identification of pollution hotspot, and potability of groundwater in shallow and deep aquifers of Palakkad and Chittur taluks (area = 1875 km²) of Bharathapuzha river basin, the largest river basin in Kerala, India, are discussed in this paper. The study area belongs to one of the rice bowls of the State. Geologically, the study area consists of Archaean crystallines, overlaid by laterite. Due to the unique geography, subhumid to semiarid climate, and intense agricultural activities, the quality of groundwater is a serious concern and warrants attention. For delineating the major ions and nutrients, water samples were analyzed for shallow (dug wells) and deep (bore wells) aquifers during monsoon (MON) and postmonsoon (POM) seasons. Physicochemical parameters showed distinct spatiotemporal variation and quality degradation, which was more prominent in deep groundwater. The relative abundance of cations and anions is in the order Na > Ca > Mg > K and HCO₃ > Cl > CO₃ for both the aquifers. The spatial distribution trend of parameters in deep and shallow aquifers showed a similar pattern indicating a common influence on water quality. Multivariate factor analysis (R-mode) employed in the study derived three main factors controlling the groundwater chemistry, viz. geogenic, anthropogenic, and pH. Among these, water chemistry is chiefly controlled by the geogenic factor and partly by the other two. It is also reflected well in the correlation analysis of various parameters. Since the eastern part of Chittur taluk in the study area is more impacted by anthropogenic and climatic influences, a pollution hotspot has been identified in this region through the application of Geographic Information System (GIS) overlay analysis. Thus, the study reveals agrochemical, climatic, and geologic influences on the chemistry and quality of groundwater.

Palakkad和Chittur taluks（面积= 1875 km ^2）的浅层和深层含水层中的水化学，离子源，污染热点的识别以及地下水的饮用能力本文讨论了印度喀拉拉邦最大的河流盆地Bharathapuzha流域。学习区属于国家的一个饭碗之一。从地质学上讲，研究区由太古岩晶体组成，被红土覆盖。由于独特的地理，半湿润至半干旱的气候以及激烈的农业活动，地下水的质量受到严重关注并值得关注。为了描述主要离子和养分，在季风（MON）和季风后（POM）季节对水样进行了浅层（挖掘井）和深层（钻孔）含水层分析。理化参数表现出明显的时空变化和质量下降，在深层地下水中尤为突出。阳离子和阴离子的相对丰度依次为Na> Ca> Mg> K和HCO ₃两个含水层的 > Cl> CO ₃。深层和浅层含水层中参数的空间分布趋势显示出相似的模式，表明对水质的共同影响。研究中采用的多元因素分析（R型）得出了控制地下水化学的三个主要因素。 成因， 人为和pH值。其中，水化学主要受地质成因控制  因素，部分由其他两个因素决定。在各种参数的相关性分析中也很好地反映了这一点。由于研究区域的Chittur taluk东部受到人为和气候影响的影响更大，因此已通过应用地理信息系统（GIS）覆盖分析确定了该地区的污染热点。因此，该研究揭示了农业化学，气候和地质因素对地下水化学和质量的影响。