Short-range-order minerals as powerful factors explaining deep soil organic carbon stock distribution: the case of a coffee agroforestry plantation on Andosols in Costa Rica
2019
Chevallier, Tiphaine | Fujisaki, Kenji | Roupsard, Olivier | Guidat, Florian | Kinoshita, Rintaro | de Melo Viginio Filho, Elias | Lehner, Peter | Albrecht, Alain | Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols) ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro) | Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad) | Centro Agronomico Tropical de Investigacion y Enseñanza (CATIE) | Obihiro University of Agriculture and Veterinary Medicine | Cafetalera Aquiares | AIRD (SAFSE) and the ANR, the French Research Agency, through two projects: Ecosfix (ANR-2010-STRA-003-01) and MACACC (ANR-13-AGRO-0005). | ANR-10-STRA-0003,ECOSFIX,Services écosystémiques des racines – redistribution hydrique, séquestration du carbone et fixation du sol(2010) | ANR-13-AGRO-0005,MACACC,Modélisation pour l'accompagnement des ACteurs, vers l'Adaptation des Couverts pérennes ou agroforestiers aux Changements globaux(2013)
International audience
اظهر المزيد [+] اقل [-]إنجليزي. Soil organic carbon (SOC) constitutes the largest terrestrial C stock, particularly in the Andosols of volcanic areas. Quantitative information on distribution of SOC stocks is needed to construct a baseline for studying temporal changes in SOC. The spatial variation of soil short-range-order minerals such as allophane usually explains the variability of topsoil SOC contents, but SOC data for deeper soil layers are needed. We found that within a 1 km2 Costa Rican basin covered by coffee agroforestry, SOC stocks in the upper 200 cm of soil were highly variable (24 to 72 kg C m−2). Topsoil SOC stocks were not correlated with SOC stocks present in deeper layers. Diffuse-reflectance mid-infrared (MIR) spectroscopy made possible the analysis of a large number of samples (69 soil profiles, i.e. 598 soil samples) for ammonium-oxalate and sodium-pyrophosphate-extractable forms of Al, Fe, and Si, as well as SOC content and bulk density. Using the MIR spectra, we identified two different soil materials, which were identified as allophanic and halloysitic soil material. Allophanic soil occurred on top of the halloysitic soil. The thickness of the allophanic soil material, rich in SRO minerals and related to a young andic A horizon, explained the variability of SOC. This study illustrates that knowledge of topography and pedogenesis is needed to understand and extrapolate the distribution of SOC stocks at landscape scales.
اظهر المزيد [+] اقل [-]المعلومات البيبليوغرافية
تم تزويد هذا السجل من قبل Institut national de la recherche agronomique