Hydrochemical Characterization And Suitability Of Groundwater In Hard Rock And Marine Environments Of Lower Tamirabharani River Basin Tamil Nadu, India

Abstract

The present work is employed in Lower Tamirabharani river basin, Tuticorin district, Tamil Nadu and India. Most of the study area is underline by the Archaean crystalline rocks. The study area is associated with active agricultural activities region. The 48 groundwater samples were collected  and analysed for major cations and anions. The irrigational parameters like; EC, Kelley’s ratio, SAR values, Mg-hazards, HCO3 and RSC have been worked out to know the suitability of the groundwater for irrigational purpose. The plotting of SAR values in USSL diagram indicates that most of the samples have low SAR value. Out of 48 samples, two samples lies in C1-S1 field, 22 samples in C3-S1, 5 samples fell in C4-S2, two samples occur in C4-S3 and 17 samples in C2-S1, field (Fig. 3 and table 3) The C2-S1 and C2-S1 field in USSL diagram is considered as good water category for irrigation use. This implies that no alkali hazard is anticipated to the crops. 22 Location (45.83%) samples occurred within C3–S1 category Analytical data of PI values plotted on Doneen’s diagram revealed that 19 samples fall in Class I, 27 samples belongs to under class-II and 2 samples fall under Class III. The sodium or alkali hazard limit for irrigation is determined by the absolute and relative concentration of cations and is expressed in terms of sodium adsorption ratio (SAR). There is a signifi­cant relationship between SAR values of irrigation water and the extent to which sodium is absorbed by the soil.