A study was conducted to assess the fertility status of soils in Appanahalli sub water shed of Gubbi taluk, Karnataka. A total of six micro watersheds under Appnahalli sub watershed with three major landforms viz., undulating upland or Ridge, Midlandand Valley under Ragi cropping system were selected. At 300 m grid interval,-180 representative soil samples were collected at 0-20 cm and 20-40 cm depth during the year 2020. Results of study indicated that soil reaction of Appanahalli sub watershed wasvery acidic to moderately alkaline in nature (4.99 to 8.13) with the mean value of 6.50. The highest mean pH value was observed in Singadahalli micro watershed (6.86). Among the three major landforms studied, pH values in lowland were better than midland and upland physiography. The soils of sub-watershed were non saline and ranged from 0.02 dSm1 to 0.48 dSnr1 in all the micro watersheds. Soil pH and EC were increased with depth. Soil Organic carbon (SOC) content was ranged from 0.13 to 0.78 per cent with a mean value of 0.50 per cent. Haradagere micro watershed recorded highest organic carbon with a mean value 0.58 per cent. However, the values of available N ranged from 123.15 kg ha~(-1) to 345.61 kg ha~(-1). The highest average (46.04 and 279.44 kgha~(-1)) available P205 and K,0 was recorded in Singadahalli and Galigkere-3 micro watershed, respectively. Available Fe, Mn, Cu, Zn and microbial biomass carbon and nitrogen contents were found in sufficiency range in surface soils of all micro watersheds. Soil organic carbon, available N, P, K, Fe, Mn, Cu and Zn contents were higher in surface soils and valley portion of watershed. Nutrient availability in a soil is governed by its pH and better nutrient availability can be expected only at neutral soil reaction. Hence, proper and adequate measures like amelioration of soil acidity/alkalinity need to be adopted for bringing the soils to favourable soil reactions to a better fertility and productivity conditions.
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