Zinc status of Kerala soils

Abstract

Total zinc in fourteen typical soil profiles of Kerala varied from 3.5-72.0 ppm in the surface horizons, 3.5-560 ppm in the second horizons and from 3 5- 100.0 ppm in the third layers, the averages for the three horizons being 21.9, 20.9 and 21.5 |-pn respectively. The variation in avaUab,e zinc was from 0.3-7.7 ppm in the surface layers, 0.8-7.7 ppm in the second layers and from 1.3-8.0 ppm in (he third horizons, the averages being 3.0, 3.2 and3.7 ppm. respectively There was significant positive correlation between total and available zinc and significant negative correlation between available zinc and nitrogen. The downward distribution of total zinc in ih- profiles was irregular, whereas available zinc increased with depth in ten of the fourteen profiles. On the basis of the threshold value of 0.55 ppm Kerala soils may be generally considered to be satisfactory with respect to available zinc.