Table 1.

Basic information of 6 sampling sites.

Location	Soil type	China soil taxonomy	Longitude	Latitude	Average altitude
Mingshui	Phaeozem	Pachic argi-udic Isohumosols	125°41′~126°42′	45°08′~45°43′	271.4 m
Lanling	Chernozem	Typic-calci-ustic argosols	125°13′~126°18′	45°13′~45°18′	400.0 m
Fuyu	Chernozem	Typic-calci-ustic argosols	124°48′~126°51′	45°37′~45°40′	162.4 m
Zhaozhou	Solonetz	Typic takyri-alkalic halosols	124°55′~125°12′	45°41′~45°49′	150.0 m
Zhaodong	Solonetz	Typic takyri-alkalic halosols	125°22′~126°22′	45°10′~46°20′	160.5 m
Dumeng	Cambosols	Typic dark aquic cambosols	124°19′~125°12′	45°46′~46°55′	146.0 m