Monitoring tree-crown scale autumn leaf phenology in a temperate forest with an integration of PlanetScope and drone remote sensing observations

Shengbiao Wu, Jing Wang, Zhengbing Yan, Guangqin Song, Yang Chen, Qin Ma, Meifeng Deng, Yuntao Wu, Yingyi Zhao, Zhengfei Guo, Zuoqiang Yuan, Guanhua Dai, Xiangtao Xu, Xi Yang, Yanjun Su, Lingli Liu, Jin Wu