Feasibility analysis of a double-cropping system for the efficient use of farmland on China’s Loess Plateau

Cropping systems worldwide have been affected by the current trend in global warming and the optimization of cropping systems is an important area of research in the transition of agricultural land. The Loess Plateau is a typical ecologically fragile region with the most serious soil erosion in China. We carried out a field experiment in Yan’an city on the Loess Plateau to explore the effect of sowing date on crop growth and yield. We then analyzed the feasibility of a double-cropping system by considering climatic adaptability, ecological suitability and economic viability. Our results showed that different sowing dates resulted in significant differences in crop growth and that appropriate early sowing can result in higher crop yields for early maturing varieties. We showed that double-cropping systems of sweet maize (Zea mays)–forage rape and feed maize–forage rape are feasible on the Loess Plateau. We discuss the implications for the efficient use of farmland, which is important in guiding agricultural supply-side reform and the development of modern agricultural management.