The cultivation phase is the biggest contributor for
CO2 emission in the system (89%), and the majority of
these emissions are due to burning of fuel wood. If
wood is not harvested for fuel purpose GWP is be found
to be seven times lesser than references systems (Figure
4). Since very little inorganic fertilizer is used in the
system the CO2-eq FU-1 is found to be four times less
compared to Palm oil system.
For Indian waste lands the average annual CO2
sequestration rate in the standing biomass per ha is
estimated to be 2.25 t CO2 ha-1 year-1. Estimates from
ICRISAT – Hyderabad (Sridevi and Wani, 2009) show
carbon sequestration capacity of 74 kg from a ten year old
tree. The amount of CO2 released by Pongamia system
(1.5 t ha-1) can be sequestered by Pongamia trees of
standing biomass of waste land and still can absorb 0.5 to
1 t of CO2, which is very encouraging.