Fig. 4: CH4 and N2O emissions from different freshwater aquaculture systems.
From: Inventory of methane and nitrous oxide emissions from freshwater aquaculture in China
a Mean of national total CH4 (bottom axis) and N2O (above axis) emissions from pond, lake, reservoir, paddy field and ditch aquaculture systems. Total emissions were estimated by multiplying the mean fluxes (Fig. 2a, d) by the aquaculture area of the aquaculture system. Bars and error bars represent mean±s.d. b Trends in CH4 and N2O emissions from each aquaculture system during the period 1980-2022. *** and ns indicate P < 0.01 and non-significant, respectively.
