Annual winter wheat mapping datasets and dynamics in China from 2001 to 2020

On this basis, we produced a long-term winter wheat mapping dataset at 30 m spatial resolution in China from 2001 to 2020 using the fusion dataset. Validations based on a total of 32,957 field survey samples displayed high accuracy, with the user’s, producer’s, and overall accuracies of 91.17%, 90.92%, and 91.6% in China, respectively. Furthermore, the identified winter wheat area aggregated to the municipal- and county-level exhibited good correlations with the agricultural statistical data.

Based on this dataset, we found that the winter wheat planting condition in China exhibited a high frequency of continuous planting, with 54.45% of pixels having continuously planted winter wheat for over 10 years. During the period of 2001–2020, approximately 40% of the winter wheat pixels showed significantly increasing trends, which mainly concentrated in the major production area for winter wheat, such as Shandong, Henan, and Anhui province.

Conversely, less than a quarter of winter wheat pixels showed significantly decreasing trends, which distributed in central and western provinces in China.