 |
| Titel |
Spatial distribution of soil organic carbon stocks in France |
| VerfasserIn |
M. P. Martin, M. Wattenbach, P. Smith, J. Meersmans, C. Jolivet, L. Boulonne, D. Arrouays |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1726-4170
|
| Digitales Dokument |
URL |
| Erschienen |
In: Biogeosciences ; 8, no. 5 ; Nr. 8, no. 5 (2011-05-04), S.1053-1065 |
| Datensatznummer |
250005806
|
| Publikation (Nr.) |
 copernicus.org/bg-8-1053-2011.pdf |
|
|
|
|
|
| Zusammenfassung |
Soil organic carbon plays a major role in the global carbon budget, and can
act as a source or a sink of atmospheric carbon, thereby possibly influencing
the course of climate change. Changes in soil organic carbon (SOC) stocks are
now taken into account in international negotiations regarding climate
change. Consequently, developing sampling schemes and models for estimating
the spatial distribution of SOC stocks is a priority. The French soil
monitoring network has been established on a 16 km × 16 km grid
and the first sampling campaign has recently been completed, providing around
2200 measurements of stocks of soil organic carbon, obtained through an in
situ composite sampling, uniformly distributed over the French territory.
We calibrated a boosted regression tree model on the observed stocks, modelling SOC stocks
as a function of other variables such as climatic parameters, vegetation net primary
productivity, soil properties and land use. The calibrated model was evaluated through
cross-validation and eventually used for estimating SOC stocks for mainland France.
Two other models were calibrated on forest and agricultural soils separately, in order
to assess more precisely the influence of pedo-climatic variables on SOC for such soils.
The boosted regression tree model showed good predictive ability, and enabled
quantification of relationships between SOC stocks and pedo-climatic variables (plus
their interactions) over the French territory. These relationships
strongly depended on the land use, and more specifically, differed between forest
soils and cultivated soil. The total estimate of SOC stocks in France was
3.260 ± 0.872 PgC for the first 30 cm. It was compared to another estimate,
based on the previously published European soil organic carbon and bulk density
maps, of 5.303 PgC. We demonstrate that the present estimate might better
represent the actual SOC stock distributions of France, and consequently that
the previously published approach at the European level greatly overestimates SOC stocks. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|