Hu Jinkang, Zhang Bing, Peng Dailiang, Huang Jianxi, Zhang Wenjuan, Zhao Bin, Li Yong, Cheng Enhui, Lou Zihang, Liu Shengwei, Yang Songlin, Tan Yunlong, Lv Yulong
Key Laboratory of Digital Earth Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, 100094, China.
International Research Center of Big Data for Sustainable Development Goals, Beijing, 100094, China.
Sci Data. 2024 Sep 27;11(1):1038. doi: 10.1038/s41597-024-03867-z.
Winter wheat constitutes approximately 20% of China's total cereal production. However, calculations of total production based on multiplying the planted area by the yield have tended to produce overestimates. In this study, we generated sample points from existing winter wheat maps and obtained samples for different years using a temporal migration method. Random forest classifiers were then constructed using optimized features extracted from spectral and phenological characteristics and elevation information. Maps of the harvested and planted areas of winter wheat in Chinese eight provinces from 2018 to 2022 were then produced. The resulting maps of the harvested areas achieved an overall accuracy of 95.06% verified by the sample points, and the correlation coefficient between the CROPGRIDS dataset is about 0.77. The harvested area was found to be about 13% smaller than the planted area, which can primarily be attributed to meteorological hazards. This study represents the first attempt to map the winter wheat harvested area at 10-m resolution in China, and it should improve the accuracy of yield estimation.
冬小麦约占中国谷物总产量的20%。然而，通过将种植面积乘以产量来计算总产量往往会产生高估。在本研究中，我们从现有的冬小麦地图中生成采样点，并使用时间迁移方法获取不同年份的样本。然后利用从光谱、物候特征和海拔信息中提取的优化特征构建随机森林分类器。进而制作了2018年至2022年中国八个省份冬小麦收获面积和种植面积的地图。通过采样点验证，所得的收获面积地图总体精度达到95.06%，与CROPGRIDS数据集的相关系数约为0.77。研究发现，收获面积比种植面积小约13%，这主要归因于气象灾害。本研究是中国首次尝试绘制10米分辨率的冬小麦收获面积地图，应能提高产量估算的准确性。
