Vulnerability of rice and maize yield in response to the climate and aerosol variability over India

Abstract

Abstract The progressive accumulation of anthropogenic aerosol pollution alters the physical and chemical properties of the atmosphere, causes extreme variations in weather variables, and has severe negative repercussions on agriculture. The present study evaluates the time series analysis of crop production, crop cultivation area, weather, and aerosol variations over the time period of the years 1998 to 2019 for rice and maize crops in India. The impact of weather and aerosol variations is also evaluated on rice and maize yield. The increasing trend of rice and maize yield is found with a rate of 0.888 million tons/year and 0.561 million tons/year over the time period of 1998 to 2019, respectively, due to the use of more sophisticated agricultural practices, optimum fertiliser, and irrigation, climate-resilient varieties, etc. The time series increasing trend is observed for the average value of weather variables (TMAX, TMIN, rainfall, relative humidity) and aerosol optical depth (AOD). While the average value of surface soil moisture (SM) and a fraction of absorbed photosynthetically active radiation (FAPAR) is found to decresing the trend over the time period 1998 to 2019. The main findings of this study are that the rice and maize yield is reduced by about (2.55%, 2.92%, 2.778%, 4.84%, 2.90%, 2.82%) and (5.12%, 6.57%, 6.93%, 6.54%, 4.97%, and 5.84%) due to the unexceptional variations in weather variables, namely maximum and minimum temperature, rainfall, relative humidity, soil moisture, and FAPAR during the time period of 1998 to 2019, respectively. However, the rice and maize yields are reduced by 7.9% and 8.8%, respectively, due to the increment of aerosol pollution. Overall, the study brings out conclusive evidence of the negative impact on rice and maize yield due to the variability in weather/FAPAR/AOD.