Identification of soil nutrients status by GIS in arjunagi sub-watershed under Northern Dry Zone of Karnataka

Abstract

Soil samples from Arjunagi sub-watershed in northern dry zone of Karnataka were drawn at 320 m grid interval and assessed for their fertility parameters. Analytical data was interpreted and statistical parameters like range, mean standard deviation, coefficient of variation, kurtosis and skewness were calculated for each parameter. Soil fertility maps were prepared for each parameter under GIS environment using Arc GIS v 10.4. Soils were neutral to strongly alkaline with non-saline to slight salinity. Majority of area in micro-watershed is low to medium in Soil organic carbon content and available phosphorous, available nitrogen was low in majority of area (94.03%), available potassium was medium to high and sulphur was low to medium. Regarding available micronutrients, zinc and iron were deficient in more than half of the sub watershed area, whereas copper and manganese were sufficient in the soils. The mapping of nutrients by GIS technique in the sub watershed revealed that, available N, P, S, Zn and Fe are important soil fertility constraints.