Table 1. Study site characteristics. Meteorological station location coordinates, elevation, and annual average temperature and annual precipitation statistics (means ± SD).

Vegetation type	Site	Location	Annual average temperature (°C)	Annual precipitation (mm)	Soil type (US soil classification-based)	Effective soil depth (m)	Soil texture (%)
							Sand	Silt	Clay
Boreal coniferous forest (BCF)	Greater Khingan Mountains	50°50′ 121°30′ 826 m a.s.l.	−4.1 ± 0.9	442.8 ± 83.9	Brown coniferous forest soil	0.6	47	35	18
Temperate mixed forest (TMF)	Changbai Mountains	42°24′ 128°05′ 738 m a.s.l.	3.1 ± 0.8	722.4 ± 108.3	Dark brown forest soil	0.6	40	35	25
Warm-temperate deciduous broadleaf forest (DBF)	Dongling Mountains	40°24′ 115°30′ 1250 m a.s.l.	5.3 ± 0.7	575.2 ± 96.5	Mountain brown soil	1.0	20	50	30
Meadow steppe (MStp)	Changling county	44°42′N, 123°45′E, 145 m a.s.l.	6.0 ± 0.8	430.5 ± 107.3	Meadow chernozem	0.5	20	45	35
Typical steppe (TStp)	Duolun county	42°02′N, 116°17′E, 1324 m a.s.l.	2.8 ± 0.9	376.0 ± 70.5	Calcis-orthic Aridisol	0.6	53	27	20
Desert steppe (DStp)	Siziwang Banner	41°46′N, 111°53′E, 1456 m a.s.l.	3.6 ± 0.9	311.6 ± 72.7	Kastanozem	0.4	65	20	15