1. Key Laboratory of Agro-ecological Processes in Subtropical Regions; Institute of Subtropical Agriculture, Chinese Academy of Sciences; Hunan 410125 People's Republic of China
2. Changsha Research Station for Agricultural and Environmental Monitoring, Institute of Subtropical Agriculture; Chinese Academy of Sciences; Hunan 410125 People's Republic of China
3. Graduate University of Chinese Academy of Sciences; Beijing 100039 People's Republic of China