Supplemental Table 1. Results of multiple linear regressions designed to explain seasonal
variation in ecosystem respiration, heterotrophic respiration and respiration of leaves, roots,
lichens and mosses. Respiration data were log-transformed (log10 + 1) prior to analysis.
Predicted respiration can be returned to units of mg CO2 g-1 hr-1 using the following equation:
respiration= (10predicted) – 1.
Component
ER
Species and
Sample Size
n=268
ER- Up-scaled
Autotrophic
n= 56
Leaf
Eriophorum
vaginatum
n= 78
Carex
bigelowii
n= 60
Betula nana
n= 65
Salix pulchra
n= 60
Root
Ledum
palustre
n= 68
Vaccinium
vitis-idaea
n= 68
Eriophorum
vaginatum
n= 43
Carex
bigelowii
n= 47
Betula nana
n= 45
Salix pulchra
n= 44
Lichen
Moss
Combined
n= 63
Hylocomium
splendens
n= 45
Sphagnum
spp.
n= 47
Combined
n= 92
Parameter
Value
SE
t
P
Intercept
Air Temperature
Thaw
LAI
Soil Water Content
Intercept
Thaw
Air Temperature
0.41562
0.01472
0.28188
0.10006
-0.00293
0.56442
0.31581
0.00945
0.04553
0.00202
0.06863
0.02553
0.00109
0.08143
0.11738
0.00360
9.13
7.28
4.11
3.92
-2.69
6.9
2.7
2.6
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
0.01
Intercept
Air Temperature
Nitrogen Concentration
Intercept
Air Temperature
Nitrogen Concentration
Intercept
Nitrogen Concentration
Air Temperature
Intercept
Air Temperature2
Nitrogen Concentration
Intercept
Air Temperature
Nitrogen Concentration
Intercept
Air Temperature
Nitrogen Concentration
Intercept
Nitrogen Concentration
Temperature
Intercept
Temperature2
Nitrogen Concentration
Day of Year
Intercept
Day of Year
Temperature
Intercept
Temperature2
Day of Year
Intercept
Air Temperature
Water Content
Nitrogen Concentration
Intercept
Moss Water Content
Nitrogen Concentration
Air Temperature2
PAR at time of Measurement
Intercept
Nitrogen Concentration
Air Temperature
PAR at time of Measurement
Intercept
Nitrogen Concentration
Air Temperature2
Moss Water Content
PAR at time of Measurement
-0.10364
0.02017
0.00882
-0.18242
0.01805
0.01134
-0.42898
0.01544
0.02331
-0.22904
0.00102
0.01239
-0.52008
0.01930
0.03916
-0.11416
0.01270
0.02339
-0.09918
0.03873
0.00985
0.25921
0.00047
0.01172
-0.00135
0.61751
-0.00225
0.01523
0.33105
0.00056
-0.00109
-0.42401
-0.00850
0.00768
0.00494
-0.14862
0.00254
0.01250
0.00256
-0.00005
-0.05416
0.01551
0.00944
-0.00004
-0.13928
0.01578
0.00025
0.00193
-0.00004
0.07433
0.00276
0.00263
0.06247
0.00256
0.00172
0.07421
0.00203
0.00282
0.06235
0.00011
0.00212
0.12948
0.00339
0.00888
0.07293
0.00243
0.00882
0.03197
0.00360
0.00229
0.04584
0.00009
0.00285
0.00029
0.10143
0.00052
0.00283
0.06212
0.00011
0.00030
0.21624
0.00150
0.00262
0.00228
0.04305
0.00040
0.00319
0.00004
0.00001
0.03519
0.00387
0.00175
0.00001
0.03823
0.00249
0.00003
0.00033
0.00001
-1.4
7.3
3.4
-2.9
7.0
6.6
-5.8
7.6
8.3
-3.7
9.3
5.9
-4.0
5.7
4.4
-1.6
5.2
2.7
-3.1
10.8
4.3
5.7
5.1
4.1
-4.7
6.1
-4.4
5.4
5.3
5.1
-3.6
-1.9
-5.7
2.9
2.2
-3.5
6.4
3.9
6.3
-4.2
-1.5
4.0
5.4
-3.9
-3.6
6.3
7.5
5.8
-5.0
0.17
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
0.12
<0.01
0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
0.05
<0.01
<0.01
0.04
<0.01
<0.01
<0.01
<0.01
<0.01
0.13
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
Partial
r2
Total
r2
0.19
0.10
0.03
0.02
0.34
0.11
0.10
0.21
0.37
0.08
0.45
0.33
0.29
0.62
0.36
0.26
0.62
0.43
0.22
0.64
0.29
0.16
0.45
0.34
0.06
0.41
0.64
0.12
0.75
0.34
0.17
0.06
0.57
0.24
0.22
0.46
0.31
0.17
0.48
0.33
0.08
0.04
0.46
0.27
0.21
0.16
0.11
0.75
0.18
0.17
0.17
0.52
0.18
0.16
0.16
0.11
0.61
Supplemental Figure 1. Seasonal leaf and moss biomass (g/m2) estimated with point hit
measurements and point hit to biomass regressions developed using data from Shaver and others
(2001). Point hit to biomass regression equations and r2 values for each species and tissue type
are listed (n = 32/species, P<0.01 in all instances). The intercept of the point hit to biomass
regressions were forced through the origin. The seasonality of leaf and moss biomass estimates
was fit with a three-parameter Gaussian curve, except B. nana leaf biomass, which was fit with a
linear model.
Supplemental Figure 2. Estimates of the seasonality of fine root standing crop for E. vaginatum
and all other species combined. A four parameter sigmoidal curve was fit to weekly standing
crop estimates.