Table 1

Effect of Open Top Chambers on air temperature

Temperature difference (OTC-Control)

(°C)

Degree days

(sum >0°C)

at 5 cm

Maximum

Minimum

Summer

Autumn

Winter

Spring

Annual

Summer

Winter

Difference

% of control


Falkland Islands

grass

0.9*

0.4'

0.3'

1.1*

0.7*

5.2 **

ns

235 *

9

dwarf shrub

0.9*

0.4'

0.2'

0.7*

0.6*

5.8 **

ns

195 *

8

Signy Island

lichen

0.8**

0.6**

1.0*

0.2'

0.7**

ns

5.3 *

103 **

31

moss

0.8**

0.4**

-0.7*

0.1'

0.3**

6.0 **

ns

148 **

49

Anchorage Island

lichen

1.2**

0.8**

2.6*

-0.8'

1.1**

9.5 **

10.3 *

80 **

21

moss

0.6**

0.7**

1.9*

-0.3'

0.8**

ns

6.8 **

26 **

10

' p < 0.1 * p < 0.05, ** p < 0.01


Mean temperature, summer maximum, winter minimum and cumulative degree day differences between OTCs and control plots at 5 cm above the soil surface. Analyses based on the mean hourly data obtained between December 2004 and November 2005 for each community. Significant differences between OTCs and control plots are indicated. Degree days were calculated with 0°C as threshold as this is the most commonly used threshold for this variable. % of control indicates the percent increase in degree days in the OTC compared to the control value.

Bokhorst et al. BMC Ecology 2007 7:15   doi:10.1186/1472-6785-7-15

Open Data