Carbon stock assessment under different ages of rubber tree plantation

Rubber tree is an important economic crop which has created economic value of Thailand. Soil acts as one of important component of the global carbon cycle as they store large amounts of organic carbon. In addition, soil organic carbon and soil organic matter are crucial component for soil quality and productivity assessment. However, they probably sensitive to plant age, ecosystem management and climate change. The objective of this study was to investigate the effect of different rubber tree plantation ages, including 1) 3 years rubber tree plantation (3Y), 2) 11 years rubber tree plantation (11Y), 3) 17 years rubber tree plantation (17Y) and 4) 27 years rubber tree plantation (27Y) on carbon stock. The result suggested that different age of rubber tree plantation has an effect on carbon stock. The highest soil carbon stock was found in 17Y, but showed no significant different when compared to 27Y. The greatest above ground biomass was observed in 27Y. Interestingly, younger age of rubber tree showed that soil carbon stock was sequestered in the form of microbial biomass carbon, due to lowest q CO 2 was determined.