Table 2

Final model results

SINDVI
All
Fell field
Dryas
Cassiope
Salix heath
Grassland
Fen

Time of snow-melt
(-)


(-)

(+)
+
Temperature (during growing season)

+
(-)




Light (during growing season)
(-)
+

(-)
U

(+)
Rain (during growing season)
(-)
+

(-)
(-)
(-)
+
SINDVI, prev. year
+
+
(+)
(+)
(+)

(+)
Temperature, prev. year
(-)
-
-
-
-
-
-

Variance explained by model (adj. R2)
0.78
0.84
0.21
0.55
0.79
0.53
0.82

DOYMAX
All
Fell field
Dryas
Cassiope
Salix heath
Grassland
Fen

Time of snow-melt
(+)
(+)
(+)
(+)
(+)
U
+
Temperature (during green-up)
(+)

(+)
(+)
(+)
U
U
Light (during green-up*)

+

(+)
(+)


Rain (during green-up*)


U
(+)
(+)


SINDVI, prev. year



-

(+)
U
Temperature, prev. year

(+)
-



U

Variance explained by model (adj. R2)
0.89
0.98
0.85
0.97
0.98
0.89
0.98

Variables included in the final models and their relation to the modeled response variables: seasonal integrated NDVI-FR (SINDVI) and the timing of maximum NDVI-FR (DOYMAX). '+' indicates that the variable has a linear positive correlation with the response variable while '-' indicates a negative linear relation. Brackets indicate a non-linear correlation but with an overall positive or negative trend. '∩' indicate a non-linear response with a maximum, and 'U' indicate a non-linear response with a minimum. Blank indicates that the variable didn't improve the model and was therefore not included * Green-up is defined from the start of the growing season to the day of maximum.

Tamstorf et al. BMC Ecology 2007 7:9   doi:10.1186/1472-6785-7-9