Assessment of the radiation effect of aerosols on maize production in China

With the recent increases in atmosphere aerosol concentration, its impact on agriculture in China is of considerable concern for scientific community. In this study, the effects that aerosols have on radiation and consequently the production of maize in China were investigated from 2002 to 2014 using the AErosol RObotic NETwork (AERONET) data, Second Simulation of a Satellite Signal in the Solar Spectrum radiative transfer (6S) model, and Agricultural Production Systems sIMulator (APSIM) model. Ten stations in the maize planting areas including Beijing, Xianghe, Taihu, Nanjing, Shanghai, Hefei, Baotou, Lanzhou, Qinghaihu, and Xuzhou stations were selected. The results showed that the APSIM-maize model, which was further calibrated, was able to simulate the interactions between maize and the climatic constraints in the maize planting areas of China. Our results indicated that aerosols obviously reduced the amount of solar radiation reaching the surface during the maize growing season in China. We also found that the aerosols have negative effects on both biomass and yield of maize in China at ten stations. The average annual maize biomass during the maize growing season from 2002 to 2014 decreased by 23.70%. The average yield of maize from 2002 to 2014 decreased by 15.10%. However, the influence of aerosol on different varieties of maize varied. We found the aerosols had greater negative impacts on summer maize than on spring maize. For spring maize, the average biomass and yield from 2002 to 2014 decreased by 10.36% and 5.16%, respectively. However, as for the summer maize, the average biomass and yield from 2002 to 2014 were reduced by 19.72% and 20.56%, respectively. Our findings can provide a useful method for estimating the effect of aerosols on crops at the national level, supporting local agricultural production in coping with the ongoing climate change.