Ecological Archives M072-004-A3

H. Jochen Schenk and Robert B. Jackson. 2002. The global biogeography of roots. Ecological Monographs 72:311-328.

Appendix C. Additional statistical tables.

Table C1. Spearman rank correlation coefficients for correlations of non-extrapolated 50 and 95% rooting depths (D50 and D95) with environmental variables (see Table 3 in the paper for definitions of variables).
 
Rooting depth
Length of warm season
Mean annual PET
Mean annual precip.
Length of dry season
Precip. surplus
Depth of organic layer
Latitude
All temperate and boreal (n = 335; organic layer: n = 315)
D50
0.362
0.343
-0.007
0.058
-0.098
-0.201
-0.332
D95
0.387
0.387
0.081
0.047
-0.021
-0.317
-0.328
Temperate and boreal forests (n = 149; organic layer: n = 132)
D50
0.295
0.207
0.243
-0.137
0.205
-0.291
-0.288
D95
0.214
0.166
0.149
-0.039
0.221
-0.322
-0.210
Temperate and boreal grass- and shrublands & savannas (n = 186; organic layer: n = 183)
D50
0.432
0.477
-0.318
0.411
-0.439
-0.293
-0.431
D95
0.475
0.490
-0.031
0.240
-0.279
-0.459
-0.415
All tropical (n = 135; organic layer: n = 130) 
D50
0.183
0.031
-0.388
0.371
-0.335
-0.071
-0.085
D95
0.240
0.218
-0.399
0.413
-0.397
-0.350
0.007
Tropical forests (n = 86; organic layer: n = 82)
D50
0.203
0.044
-0.244
0.230
-0.188
0.079
-0.004
D95
0.272
0.300
-0.274
0.340
-0.352
-0.338
0.141
Tropical grass- and shrublands and savannas (n = 49) 
D50
N/A
-0.125
-0.413
0.313
-0.357
N/A
-0.182
D95
N/A
0.013
-0.176
0.110
-0.062
N/A
-0.202

    Notes: Coefficients marked in boldface are statistically significant at P < 0.01; those marked in bold italics are significant at P < 0.05. Significance levels were not adjusted for multiple comparisons.

 

Table C2. Spearman rank correlation coefficients for correlations of rooting depths with environmental variables (see Table 3 in paper for definitions of variables).
 
Rooting depth
Length of warm season
Mean annual PET
Mean annual precip.
Length of dry season 
Precip. surplus
Depth of organic layer
Latitude
Non-extrapolated profiles (n = 96; organic layer: n = 94)
D50
0.392
0.448
-0.070
0.200
-0.153
-0.403
-0.390
D95
0.570
0.567
-0.051
0.177
-0.058
-0.481
-0.582
Extrapolated profiles (n = 374; organic layer: n = 351) 
Dx50
0.195
0.194
-0.080
0.101
-0.157
-0.136
-0.138
Dx95
0.169
0.208
-0.023
0.109
-0.111
-0.299
-0.075

   Notes: Listed are the coefficients for non-extrapolated 50 and 95% rooting depths (D50 and D95) of profiles sampled to the maximum rooting depth or to at least 2 m depth and the coefficients for extrapolated 50 and 95% rooting depths (Dx50 and Dx95) profiles sampled to less than 2 m depth. Coefficients marked in boldface are statistically significant at P < 0.01; those marked in bold italics are significant at P < 0.05. Significance levels were not adjusted for multiple comparisons.


[Back to M072-004]