Vol. 11, Issue 12 (2022)

A survey was carried out in the farmer’s field in three taluks of Udupi district viz., Udupi, Kundapura and Karkala taluks during the period of 2019 to 2021 in order to know the “Status of major nutrients under Arecanut based cropping systems in the coastal region of Udupi district”. The soil samples were analysed for chemical properties and also different forms of soil iron was estimated from randomly selected soil samples. The results revealed that soils were extremely acidic to strongly acidic range with pH ranged from 4.03 to 6.60, organic carbon status was medium to high with normal electrical conductivity. The cation exchange capacity of soils ranged from 2.34 to 10.02 cmol (p+) kg^-1. Forms of iron such as available iron, exchangeable iron, organically bound iron, crystalline oxide bound iron, amorphous oxide bound iron and total iron in soils ranged from 12.26 to 29.12, 1.22 to 17.05, 2.97 to 9.96, 310 to 2278.1, 271.54 to 1204.80, 603.90 to 3541.96 mg kg^-1 with an average value of 19.61, 8.95, 5.50, 910.27, 754, 1732.85 mg kg^-1, respectively. Among the iron forms, crystalline oxide bound iron was found to be the dominant fraction. Correlation results indicated that all the iron forms had positive and significant relationship between them. Total iron showed positive and significant correlation with crystalline oxide bound, amorphous oxide bound, available and exchangeable iron. It showed positive correlation but non-significant with amorphous and organically bound iron.