Potential Yield of Potato Under Global Warming Based on an ARIMA-TR Model
摘要
As an important food crop in the world, potato has been attracting scholarly attention to improve its yield in the future, particularly under climate change. Therefore, analyzing the potential yield of potato as affected by global warming is of great significance to direct the production of crops worldwide. However, up to now, most research reports estimated the potential yield of potatoes by models which are based on the theory of production functions while there are few theoretical studies on the time-series approach based on stationary stochastic processes. Thus, in this paper, both average and top (national) yields of potato between 2021 and 2030 are projected creatively using an auto-regressive integrated moving average and trend regression (ARIMA-TR) model basing the projection on historic yields from 1961 to 2020 to explore the potential yield of the crop in the future; the effects of global warming on both average and top (national) yields of potato from 1961 to 2020 are analyzed using binary regression models in which global mean temperature is treated as the independent variable and the yield as the dependent variable, to reveal how climatic events drive the variation trend of these two types of yield. Our results show that between 2021 and 2030, the average yield of potato is projected to be from 21,234 to 23,773 kg/ha while the top yield ranges from 50,240 to 51,452 kg/ha; the average will approach from 42.26 to 46.20% of the top, or the gap between these two yields will be gradually narrowed in the ensuing decade; from 1961 to 2020, global warming exerts a positive effect on the average yield of potato with a quadratic function (R-squared = 0.772 and F = 96.417) more than on the top yield with an inverse function (R-squared = 0.568 and F = 76.201), which partly makes the gap between these two types of yields shrink. Our study concludes that for potato by 2030, the opportunities for improving global production should be dependent on both high- and low-yield countries as the average yield is in the main body of an S-shaped curve in the evolutionary trend in the long run. These insights provide the academic circle with innovative comprehension of the potential yield of potato for global food security under climate change.