Soil Nutrient Index of the Semi-Arid Region of Kolar Taluk, Karnataka, India

A study highlights the estimation of soil nutrient content of thirty-seven samples that were collected randomly in Kolar Taluk during the pre-monsoon season, 2022. Kolar Taluk lies geographically between 13° 02′ 03′′ and 13°19′11′′ Northern Latitudes and 77° 56′ 02′′ and 78° 13′ 02′′ eastern longitudes. The Organic Carbon, available Phosphorus, and Potassium were analyzed as per Standard Methods. The results of the soil fertility level showed little variation across different landforms. Organic matter and its decomposition rate differed among the soils. 2.4 to 3.4% of organic carbon. 97% had a higher level of Phosphorus with a range of 33.80 -511.13 kg/ha, whereas 54.05% were doubtful. The available potash supply is 113.42-279.05 kg/ha. ESP, SAR ratio indicated that the soils were found to be highly suitable for irrigation. The quality of Soil falls into the High-High-Low (HHL) category as per the nutrient index. This classification is primarily based on the amount of available Phosphorus, Organic Carbon, and Potassium, and these index values would help in the maintenance of soil fertility and suitable crops.