Water quality of coffee plantations during pre-monsoon and post-monsoon seasons in the western ghats, Ponnampet, Kodagu district, Karnataka, India

Surface water resources, crucial for irrigation in the coffee-growing areas of Ponampet Taluk, Kodagu District, are deteriorating due to changes in the Western Ghats caused by agricultural and human activities. This study assessed water quality by collecting 50 surface water samples from various coffee-growing areas during the pre-monsoon and post-monsoon seasons. The samples were analyzed for physicochemical properties essential for irrigation. Both seasons' samples showed slightly alkaline characteristics, with all anionic and cationic indicators within BIS (2012) guidelines. Water suitability for irrigation was evaluated using parameters such as sodium adsorption ratio (SAR), residual sodium carbonate (RSC), soluble sodium percentage (SSP), magnesium hardness (MH), Kelley’s index, permeability index (PI), and percent sodium. Most samples were deemed suitable based on SAR and RSC values, with percent sodium and SSP ranging from excellent to permissible. Overall study indicates the post-monsoon water samples were less contaminated and better suited for irrigation compared to pre-monsoon samples.