Since the study compared the environmental performance of
approaches to the control of water hyacinth proliferation, the
photosynthesis of water hyacinth was not included. The considered
GHGs include CO2, CH4 and N2O. The total emission of CO2 equivalent
is summed up according to their global warming effects. That
is, the global warming potential of CH4 and N2O are 23 and 296
times that of CO2 for a 100-year time horizon (IPCC, 2001).