Table 1. Basic parameters and soil characteristics of the three sampling sites.

Sampling sites	Longitude	Latitude	Elevation (m)	pH	Total N (g·kg-1)	Total P (g·kg-1)
Dagang	114°56'31"E	28°37'17"N	381.0	5.16±0.09a	4.65±0.10a	0.27±0.03b
Guanshan	114°34'47"E	28°33'35"N	548.0	4.37±0.07b	2.51±0.09c	0.33±0.04b
Dajing	114°8'19"E	26°34'8"N	1105.0	4.39±0.06b	3.44±0.08b	0.54±0.07a

Notes: Value = Mean ± standard error. n = 5. The different letters indicated the significant differences among the three sampling sites at the level of p<0.05.