Organic Matter Level and Some Related Characteristics of Lateritic Soils of Different Altitude under Plantation

Profile soil samples collected from Pudukottai (350 m above msl) and Kodaikanal (2237 m) representing low and high level lateritic soils under plantation of Eucalyptus tereticornis and E. globulus, respectively, are sandy loam in texture, acidic in reaction without any salinity problem. The soils from Kodaikanal (low temperature high rainfall zone) contained much higher amounts of organic carbon (0.44 to 9.74%) than those from Pudukottai (0.10 to 1.14%). The organic carbon content decreased with depth. Carbon dioxide evolution, as an index of soil fertility, was higher in Kodaikanal soils and showed a significant positive correlation (r=0.945) with organic carbon content.