Carbon storage and sequestration potential of selected tree species in India

Abstract

A dynamic growth model (CO2FIX) was used for estimating the carbon sequestration potential of sal (Shorea Robusta Gaertn. f.), Eucalyptus (Eucalyptus Tereticornis Sm.), poplar (Populus Deltoides Marsh), and teak (Tectona Grandis Linn. f.) forests in India. The results indicate that long-term total carbon storage ranges from 101 to 156 Mg C ha−1, with the largest carbon stock in the living biomass of long rotation sal forests (82 Mg C ha−1). The net annual carbon sequestration rates were achieved for fast growing short rotation poplar (8 Mg C ha−1 yr−1) and Eucalyptus (6 Mg C ha−1 yr−1) plantations followed by moderate growing teak forests (2 Mg C ha−1 yr−1) and slow growing long rotation sal forests (1 Mg C ha−1 yr−1). Due to fast growth rate and adaptability to a range of environments, short rotation plantations, in addition to carbon storage rapidly produce biomass for energy and contribute to reduced greenhouse gas emissions. We also used the model to evaluate the effect of changing rotation length and thinning regime on carbon stocks of forest ecosystem (trees + soil) and wood products, respectively for sal and teak forests. The carbon stock in soil and products was less sensitive than carbon stock of trees to the change in rotation length. Extending rotation length from the recommended 120 to 150 years increased the average carbon stock of forest ecosystem (trees + soil) by 12%. The net primary productivity was highest (3.7 Mg ha−1 yr−1) when a 60-year rotation length was applied but decreased with increasing rotation length (e.g., 1.7 Mg ha−1 yr−1) at 150 years. Goal of maximum carbon storage and production of more valuable saw logs can be achieved from longer rotation lengths. ‘No thinning’ has the largest biomass, but from an economical perspective, there will be no wood available from thinning operations to replace fossil fuel for bioenergy and to the pulp industry and such patches have high risks of forest fires, insects etc. Extended rotation lengths and reduced thinning intensity could enhance the long-term capacity of forest ecosystems to sequester carbon. While accounting for effects of climate change, a combination of bioenergy and carbon sequestration will be best to mitigation of CO2 emission in the long term.