soil metagenome
We established spatially independent plots at four sites:6(Linan,Zhejiang), 6(Guyuan,Ningxia), 9 (Tiantong,Zhejiang), and 8(Fukang,Xinjiang). At each plot, nine 0-10 cm soil cores were collected along an S-shaped transect and composited into 29 total samples. Soils were stored on ice, transported to the lab within 1-2 days, and sieved to 2 mm. Fresh samples were used to sequencing.