Predicting Maize Productivity Under Climate Change in the Semiarid Region of Northwest China Through the AquaCrop Model

Abstract

An increasingly warm, dry climate and the rise in atmospheric carbon dioxide concentration are having profound impacts on agricultural production. Maize (Zea mays L.) is the second most important cereal crop in Gasu province of China, playing a key role in national food security. The objective of this study was to predict the consequence of climate change on spring maize yield using the AquaCrop model. The AquaCrop model was firstly calibrated using the climate data collected from a baseline period of 1981-2020 to simulate past trends in spring maize yields. The model was further used to predict maize yield under different climate scenarios with changes in temperature (-2℃-2℃), precipitation (-20%-20%), and evapotranspiration (ET0) (-25%-25%). Results showed that maize yield continued to grow under the influence of climate change. The grain yield was far more sensitive to climate change than the above-ground biomass. Grain yield was highly associated with the meteorological factors, with temperature resulting in a greater impact compared to ET0, and precipitation. Increasing temperature and precipitation, and decreasing ET0 resulted in higher spring maize productivity. These results highlight the importance of climate change on spring maize production in the semi-acid region, and suggest that soil temperature and moisture are the key limiting factors for agricultural production.