Effect of drying and wetting on the physical, Physico-chemical and chemical properties of the submerged soils of Kuttanad

Abstract

A study was undertaken at the College of Agriculture, Vellayani to know the effect of drying and wetting on the physico-chemical properties of submerged acid sulphate soils of Kuttanad which are known locally as Kerapadom, Kari and Kayal soils. Random soil samples were collected from various parts of Kuttanad and their physico-chemical properties such as pH, conductivity, available NPK status and different forms of iron and aluminium were estimated in moist state itself. Texturally Kuttanad soils were predominantly of clayay nature. Bulk and particle densities were significantly lower in Kari soils due to high organic matter as compared to Karapadom and Kayal soil. The pH values of Kayal soils were significantly higher than that of Kari and Karapadom soils which were extremely acidic. The conductivity of all soil groups were negligible probably due to seasonal effects and also due to the commissioning of Thaneermukkom bund and Thottapally spillway which prevented the ingress of sea water. The availability of major nutrients was fairly high and no significant differences existed between soils. Exchangeable iron and aluminium varied greatly.