Identifying the spatiotemporal changes of annual harvesting areas for three staple crops in China by integrating multi-data sources

作者：Yuchuan Luo, Zhao Zhang, Ziyue Li, Yi Chen, Liangliang Zhang, Juan Cao, Fulu Tao · 发表于：Environmental Research Letters · 年份：2020 · DOI：10.1088/1748-9326/ab80f0 · 被引用次数：224 · 研究领域：Remote Sensing in Agriculture、Land Use and Ecosystem Services、Leaf Properties and Growth Measurement

Abstract Reliable and continuous information on major crop harvesting areas is fundamental to investigate land surface dynamics and make policies affecting agricultural production, land use, and sustainable development. However, there is currently no spatially explicit and time-continuous crop harvesting area information with a high resolution for China. The spatiotemporal patterns of major crop harvesting areas at a national scale have rarely been investigated. In this study, we proposed a new crop phenology-based crop mapping approach to generate a 1 km harvesting area dataset for three staple crops (i.e. rice, wheat, and maize) in China from 2000 to 2015 based on GLASS leaf area index (LAI) products. First, we retrieved key phenological dates of the three staple crops by combining the inflexion- and threshold-based methods. Then, we determined the grids cultivated for a certain crop if its three key phenological dates could be simultaneously identified. Finally, we developed crop classification maps and a dataset of annual harvesting areas (ChinaCropArea1 km), comprehensively considering the characteristics of crop phenology and the references of drylands and paddy fields. Compared with the county-level agricultural statistical data, the crop classification had a high accuracy, with R 2 values consistently greater than 0.8. The spatiotemporal patterns of major crop harvesting areas during the period were further analyzed. The results showed that paddy rice harvesting areas...