Figure 1

Figure 2

Figure 3

Figure 4

List of datasets from Austria (AT), Switzerland (CH) and Italy (IT) naming sources, number of samples, land-use and mean, lowest (min) and highest (max) elevation of the sites sampledTabelle 1_ listet die Datensammlungen aus Österreich (AT), Schweiz (CH) und Italien (IT) mit Quellen, Anzahl Bodenprobe, Landnutzung und mittlere (mean), minimale (min) und maximimale (max) Höhenlage der Probenstellen_
| Country | Made available by | number of samples | Land-use | elevation (m asl) | |||
|---|---|---|---|---|---|---|---|
| mean | min | max | |||||
| AT | our own dataset | 15 | Grassland | 909 | 672 | - | 1554 |
| AT | Upper Austria (BORIS) | 567 | cropland | 540 | 400 | - | 1140 |
| AT | Upper Austria (BORIS) | 656 | Grassland | 1047 | 410 | - | 2460 |
| AT | BAW (internal dataset) | 348 | Forest | 1024 | 400 | - | 2050 |
| AT | A. Bohner (other studies) | 18 | Grassland | 663 | 420 | - | 1830 |
| CH | J. Leifeld | 116 | Grassland | 760 | 430 | - | 1220 |
| IT | EURAC | 12 | Grassland | 1607 | 986 | - | 2043 |
Mean, minimum (min) and maximum (max) values of soil depth, organic carbon (SOC), sand, silt, clay and bulk density according to the datasets: all data, cropland, forest and grassland (n = number of samples)Tabelle 2_ Mittlere (mean), minimale (min) und maximale (max) Werte der Bodenprobeentnahme, organischem Bodenkohlenstoff (SOC), Sand-, Schuff-, Tongehalten und der Bodenlagerungsdichten (BD) von ‚allen Daten‘, Ackerböden, Wald- und Grünlandböden (n = Anzahl Proben)
| parameter | all data (n = 1732) | cropland (n = 567) | forest (n = 348) | grassland (n = 817) | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| mean | min | max | mean | min | max | mean | min | Max | mean | min | max | |||||
| Depth [cm] | 20 | 1 | - | 70 | 26 | 10 | - | 50 | 27 | 8 | - | 60 | 12 | 1 | - | 70 |
| SOC [mg g−1] | 39 | 1 | - | 295 | 19 | 4 | - | 120 | 32 | 10 | - | 185 | 55 | 1 | - | 295 |
| Sand [mg g−1] | 280 | 0 | - | 910 | 217 | 0 | - | 721 | 35 | 21 | - | 717 | 289 | 18 | - | 910 |
| Silt [mg g−1] | 538 | 2 | - | 934 | 587 | 172 | - | 934 | 446 | 172 | - | 703 | 544 | 20 | - | 882 |
| Clay [mg g−1] | 184 | 1 | - | 701 | 197 | 35 | - | 467 | 207 | 36 | - | 701 | 167 | 10 | - | 560 |
| BD [g cm−3] | 1.2 | 0.3 | - | 2.2 | 1.4 | 0.5 | - | 1.7 | 1 | 0.4 | - | 2.2 | 1.1 | 0.3 | - | 1.7 |
Coefficients of the linear model equations (EQ) and the evaluation of the models by R squared (R2), root mean squared error (RMSE) and percentage of uncertainty (PU) together with the validation by the mean squared R (mR2) of the cross validation (CV)Tabelle 3_ Die Koeffizienten der linearen Gleichungen (EQ) und die Evaluierung der Modelle anhand des Bestimmtheitsmaß (R2), Wurzel der Mittlere quadratische Abweichung (RMSE) und dem Prozent der Unsicherheit (PU) gemeinsam mit dem Ergebnis der Validierung durch mittleres Bestimmtheitsmaß (mR2) aus der Kreuzvalidierung (CV)
| EQ | landuse | Intercept | Depth [cm] | SOC−0.5 [%]0.5 | Silt [%] | Clay [%] | R2 | RMSE | PU [%] | CV mR2 |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | all data | 1.650 | −0.0022*** | −0.3157*** | 0.0028* | 0.58 | 0.190 | 21 | 0.57 | |
| 2 | cropland | 1.873 | −0.0021*** | −0.3042*** | 0.43 | 0,105 | 9 | 0.41 | ||
| 3 | forest | 1.523 | −0.3199*** | 0.58 | 0.205 | 25 | 0.56 | |||
| 4 | grassland | 1.698 | −0.2737*** | 0.0009** | −0.0020** | 0.65 | 0.171 | 17 | 0.65 | |
| 5 | all data | 1.682 | −0.2738*** | 0.55 | 0.197 | 24 | ||||
| 6 | cropland | 1.720 | −0.2306*** | 0.41 | 0.107 | 9 | ||||
| 7 | grassland | 1.693 | −0.2635*** | 0.65 | 0.157 | 18 |