Estimation of Soil Organic Carbon Pools and Biomass Carbon Stocks in Different Aged Rubber (Hevea brasiliensis Muell. Arg.) Plantations of Tripura

Abstract

Soil organic carbon (SOC) dynamics is an important factor for understanding the soil properties, biomass carbon, and changes of the SOC pools. Though, SOC has been recorded in all carbon fractions, it is not adequately distinguishing between the active carbon (AC) and passive carbon (PC) fractions. Therefore, this study was undertaken to determine the above ground biomass (AGB), SOC stocks changes, AC and PC pools along with their variations in different aged rubber stands viz. 5, 10, 15, 20, 25, 30 and 35 years. The results show that above ground carbon (AGC) production and SOC stocks ranged between 28.4-272.9 Mg ha-1 and 96.2-108.1 Mg ha-1, respectively. While the total ecosystem carbon ranges from 131.2-459.1 Mg ha-1. The amount of very labile carbon (VLC) and labile carbon (LC) were observed much higher in 5-15 years rubber plantations. Whereas, the less labile carbon (LLC) and non labile carbon (NLC) were recorded highest in 30-35 years stand. Overall, 35 years stand showed the highest biomass and soil organic carbon stocks compared to younger stands due to a huge amount of vegetation carbon. Thus, the present study provides an insight that the increasing trend of PC pools and the SOC stocks is typically dependent on the maturity of the rubber stands along with their biomass and their related annual litterfall productions.