We estimated the mean residence time of soil organic carbon in central Indian forest.

The MRT is of the order of a century at the surface and reaches to 3–5 kyr at 100 cm.

A modified Rayleigh model is applied to study the evolution of δ¹³C in soils.

Tropical forest soils acts almost as a close system with respect to carbon.

The fresh organic matter from the surface into deeper soil layers is insignificant.