Mapping abandoned cropland in tropical/subtropical monsoon areas with multiple crop maturity patterns

作者：Guilin Liu, Yuecheng Li, Chen Yang, Yongquan Lu, Desheng Jiang, Aojie Xu, Yuqi Zhong, He Yin · 发表于：International Journal of Applied Earth Observation and Geoinformation · 年份：2024 · DOI：10.1016/j.jag.2024.103674 · 被引用次数：8 · 研究领域：Land Use and Ecosystem Services、Remote Sensing in Agriculture、Remote Sensing and Land Use

Cropland abandonment has become a global land use change phenomenon that threatens food security. Identifying abandoned cropland in time and space can provide important data for cropland and agricultural management. In tropical/subtropical monsoon areas, sufficient water and thermal conditions allow crops to grow year-round, yet the specific crops grown vary in the dry and rainy seasons. However, the lack of optical remote sensing observations in the rainy season due to massive cloud cover and rainy weather makes it difficult to monitor abandoned cropland. Furthermore, when crops have multiple maturities and abandonment patterns, the mapping of abandoned croplands using remote sensing data at the annual scale is even more challenging. To resolve these problems, we proposed an approach for identifying abandoned croplands at the growing season scale. First, we used daily MODIS data to estimate the early and late growing seasons from 2013 to 2022. Then, we synthesized all available Landsat and Sentinel data to reduce the problem of inadequate remote sensing observations in the two growing seasons. Subsequently, we determined an NDVI threshold at the start of each growing season. In addition, we obtained the fitted NDVI curves for each growing season using the LandTrendr algorithm. Then, we determined the cultivated status by comparing the fitted NDVI curves with the NDVI threshold and then generated time series cultivated/noncultivated status maps. Finally, a temporal moving win...