Impacts of global warming on the cropping systems of China under technical improvements from 1961 to 2016

Abstract

AbstractThe multiple cropping systems (MCS) have been crucial for China's food security due to its limited arable land and the increased population for hundreds of years. Global warming has significantly affected MCS in China during recent decades. However, whether global warming has influenced the MCS in China under technical improvement is still uncertain and has received great attention. Thus, the current study aims to evaluate the impacts of global warming within the improvements of crop cultivars on MCS in China and analyze the changes in cropland and actual cropping area during the past five decades. Our results showed that the cumulative temperature above 0 °C for the double‐cropping system (DCS) and triple‐cropping system (TCS), respectively, increased by 400 and 100 °C compared to the values in the 1980s. The northern limit of the DCS shifted Southward, while the northern limit of the TCS moved Northward. The cropland of the single‐cropping system (SCS) and TCS increased while the cropland of the DCS decreased. Specifically, the winter wheat (Triticum aestivum L.) area, which represents the DCS in northern China, decreased during the past decades. Similarly, the double‐rice (Oryza sativa L.) cropping system area, which represents the TCS in southern China, decreased as it was partly replaced by single‐rice cropping system. Our study indicated that the cropping intensity in China decreased during past decades, and the full use of MCS will lead to high grain production potential in the transition area. The results will be beneficial for optimizing the cropping distribution across China and enhance the food security.