SOIL ORGANIC CARBON APPRAISAL IN A SEMI-EVERGREEN FOREST, EASTERN GHATS OF INDIA AS A RESULT OF DEGRADATION - A GEOSPATIAL STUDY

Tropical forests have variety of biodiversity values, which provide invaluable services to the living being on earth. In the recent years, tropical forests are regarded as valuable global resources that act as sink for carbon dioxide in order to mitigate global climatic change. In many parts of the world, tropical forests are being rapidly cleared by various means. Soil organic carbon (SOC) is concentrated in the upper 12 inches of the soil. So it is readily depleted owing to the degradation activities. In the present study, it was aimed to assess the magnitude of disturbance in the availability of SOC in a semi- evergreen forest, situated in the Eastern Ghats of Tamil Nadu, India. The forest density of this region was mapped with QuickBird satellite data. Intensive field soil sampling and floristic study were conducted to estimate the SOC status in different density classes and to identify the species availability. The SOC density ranged from 274.06 t/ha to 147.84 t/ha in the very dense and degraded semi-evergreen forest respectively. The SOC content was also varied from 3.70 to 1.83 % in the very dense semi-evergreen and medium semi-evergreen forests respectively. The species composition in different density classes was also varied considerably. As a result of this study, it was identified that the disturbance to forests by various means not only affect the density of forests but also affect the below ground SOC status proportionately.