Table 1.

Geographical locations and environmental conditions of studied sites in northern hemisphere grassland transects.

Site	Region	Grassland type	LAT (°N)	LONG (°E)	ALT (m)	PAR(mol·m-2·d-1)	MAP(mm)	SNP	MAT (°C)
1	MP	MD	44.59	123.51	144	31.88	448.47	2.49	5.10
2	MP	MD	44.52	121.04	269	33.72	384.39	6.52	5.80
3	MP	MD	45.11	120.33	660	34.47	384.47	5.86	3.72
4	MP	TG	44.77	118.36	1019	35.61	403.58	5.75	0.56
5	MP	TG	44.26	116.52	1129	36.32	315.49	3.63	1.17
6	MP	TG	43.55	116.67	1272	36.05	385.81	3.98	0.16
7	MP	TG	44.51	117.68	1024	35.47	344.68	6.18	1.96
8	MP	DG	44.01	114.89	1101	36.75	281.18	3.85	0.10
9	MP	DG	43.84	113.50	1022	37.09	213.16	2.22	2.47
10	MP	DG	43.63	112.15	955	36.79	168.29	1.57	3.69
11	LP	MD	36.29	113.36	804	28.93	563.88	1.99	11.85
12	LP	MD	35.99	112.29	894	29.70	591.18	3.72	9.96
13	LP	MD	35.99	111.64	833	29.40	566.12	2.73	10.66
14	LP	TG	36.07	110.18	966	32.54	533.36	1.94	10.72
15	LP	TG	36.74	109.24	1268	35.46	498.89	1.60	9.50
16	LP	TG	36.93	107.92	1383	36.21	438.09	1.70	7.46
17	LP	TG	37.58	107.19	1535	37.26	395.14	1.65	5.23
18	LP	DG	37.42	105.78	1293	37.22	320.35	1.37	5.87
19	LP	DG	37.44	104.92	1378	36.81	233.88	1.00	7.56
20	LP	DG	37.46	104.44	1714	36.69	215.50	1.06	7.71
21	TP	MD	31.46	95.45	4104	35.80	619.86	7.74	0.41
22	TP	MD	31.85	93.53	4509	35.70	536.77	5.39	-1.50
23	TP	MD	31.64	92.01	4587	36.77	501.38	6.74	-4.37
24	TP	TG	31.38	90.74	4617	37.53	526.89	3.75	-6.76
25	TP	TG	31.54	89.72	4588	37.24	443.79	4.94	-3.06
26	TP	TG	31.87	87.82	4570	39.01	389.09	5.62	-2.57
27	TP	TG	31.92	85.84	4938	39.77	376.17	2.62	-3.77
28	TP	DG	32.41	83.34	4578	40.21	317.13	1.02	-3.90
29	TP	DG	32.30	81.23	4558	41.13	291.42	0.79	-3.49
30	TP	DG	32.48	80.15	4328	41.92	191.71	1.15	-1.27

MP, Mongolia Plateau; LP, Loess Plateau; TP, Tibet Plateau; MD, meadow; TG, typical grassland; DG, desert grassland; LAT, latitude; LONG, longitude; ALT, altitude; PAR, photosynthetic active radiation; MAP, mean annual precipitation; SNP, the ratio of soil nitrogen to phosphorus; MAT, mean annual temperature.