Vol. 11, Special Issue 12 (2022)

Author(s):
T Kantharaj, KV Sudhir Kamath, Lakshmana and SM Jayaprakash

Abstract:
A survey was conducted to evaluate the fertility status of soils under traditional paddy land cover in Udupi district, Coastal Karnataka during 2019-20. In this study an assessment of physico-chemical properties viz., soil acidity classification, electrical conductivity, soil organic carbon content, available N, P₂O₅, K₂O, S and micronutrient status were carried out in 741 soil samples collected from paddy growing fields in Udupi, Kundapura and Karkala taluks. The results on soil acidity indicated 73.01 percent soils were neutral pH with average of 6.51, 17.68 percent under medium acidic (5.87 average pH), 6.88 percent under strongly acidic (5.37 average pH), 2.29 percent under very strongly acidic (4.77) and only 0.13 percent under extremely acidic (4.38 average pH) in entire Udupi district. The soils of Kundapura had highest mean value of 13.4 g kg^-1 organic carbon content than Karkala (12.7 g kg^-1) and Udupi soils (11.4 g kg^-1). Very low status of available nitrogen in soil was distributed with average of 92.1 kg ha^-1 and soils contained narrow range of 8.5 to 217.9 kg N ha^-1 in entire Udupi district. Udupi soils had 72.9 percent, Kundapura soils had 48.6 percent and Karkala soils had 22.0 percent distribution under high status of available phosphorus within the range of 0.3-343.5 kg ha^-1. The available potassium ranged from 14.9 to 983.3 kg ha^-1 with average value of 190.6 kg ha^-1 which revealed that 77.4 percent soils were distributed under low status in Kundapura followed by Udupi (77.1%) and Karkala (57.1%) soils. The available nitrogen content was very low fertility rate (NI=1.0) in the entire district. The available phosphorus content was high (2.63 NI) in Udupi soils than Kundapura (2.28) and Karkala (1.74) soils were classified under medium NI. The nutrient indices of Udupi soils (1.75) remained medium fertility rate with respect to available potassium status wherein, Karkala and Kundapura soils were low (> 1.60 NI).