Table 1 Comparisons of environment types at the study sites

Elevation (m)

618

670

1169

Vegetation type

Spruce forest

Shrub tundra

Alpine tundra

Two dominant species (or growth forms)

Moss

Moss

Dryas

Empetrum

Lichens

Graminoids

Summer 2011

Air temperature mean (°C)

Ambient

n/a

10.36

9.27

Inside greenhouse

n/a

13.73

12.11

Mean of daily maximum

Ambient

22.4*

18.60

15.03

Inside greenhouse

31.39*

25.41

21.01

Mean of daily minimum

Ambient

6.07*

4.25

4.94

Inside greenhouse

7.13*

5.63

6.20

Soil temperature mean (°C)

Ambient

3.42

n/a

n/a

Inside greenhouse

8.60

n/a

n/a

2012 Soil temperature mean (°C)

Ambient

9.75

3.69

8.91

Inside greenhouse

10.00

10.41

8.94

2010 Air temperature mean (°C)

Ambient

12.51

10.69

8.73

Inside greenhouse

15.73

16.91

12.39

January 2011 Air temperature mean (°C)

−15.60

−13.13

−9.51

Light (μmol m-2 s-1) Sunny day

Ambient*

1656.50

n/a

1276.57

Inside greenhouse*

1241.52

n/a

855.70

Light (μmol m-2 s-1) Cloudy day

Ambient*

376.86

512.17

500.58

Inside greenhouse*

164.85

318.85

382.99

Air % Relative humidity (%)

Ambient

n/a

93.56

86.88

Inside greenhouse

n/a

72.19

80.21

2012 Air Relative humidity (%)

Ambient

78.23

84.61

81.20

Inside greenhouse

73.17

67.12

71.91

Soil % Volumetric water content

Ambient*

n/a

47.15

23.60

Inside greenhouse*

n/a

35.00

19.50

Soil % Volumetric water content (Sampling)

53.42

52.49

20.36

Soil CN ratio

17.72

8.63

13.26

Soil texture

Sandy Loam

Loam

Sandy Clay Loam

Soil Bulk density (g/cm3)

0.182

0.795

0.559

Soil pH

6.0

5.0

6.5

Depth of thaw (cm)*

74.83

72.71

45.00