1. State Key Laboratory of Grassland Agro-Ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, China 2. Key Laboratory for Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, China †Hongyin Hu, Pengchuan Sun and Yongzhi Yang contributed equally to this work. *Correspondence: Jianquan Liu (liujq@nwipb.cas.cn)