Controls on timescales of soil organic carbon persistence across sub-Saharan Africa

A - Papers appearing in refereed journals

Fromm, S. F. V., Doetterl, S., Butler, B. M., Aynekulu, E., Berhe, A. A., Haefele, S. M., McGrath, S. P., Shepherd, K. D., Six, J., Tamene, L., Tondoh, E. J., Vagen, T., Winowiecki, L. A., Trumbore, S. E. and Hoyt, A. M. 2024. Controls on timescales of soil organic carbon persistence across sub-Saharan Africa. Global Change Biology. 30 (1), p. e17089. https://doi.org/10.1111/gcb.17089

AuthorsFromm, S. F. V., Doetterl, S., Butler, B. M., Aynekulu, E., Berhe, A. A., Haefele, S. M., McGrath, S. P., Shepherd, K. D., Six, J., Tamene, L., Tondoh, E. J., Vagen, T., Winowiecki, L. A., Trumbore, S. E. and Hoyt, A. M.
Abstract

Given the importance of soil for the global carbon cycle, it is essential to understand not only how much carbon soil stores but also how long this carbon persists. Previous studies have shown that the amount and age of soil carbon are strongly affected by the interaction of climate, vegetation, and mineralogy. However, these findings are primarily based on studies from temperate regions and from fine-scale studies, leaving large knowledge gaps for soils from understudied regions such as sub-Saharan Africa. In addition, there is a lack of data to validate modeled soil C dynamics at broad scales. Here, we present insights into organic carbon cycling, based on a new broad-scale radiocarbon and mineral dataset for sub-Saharan Africa. We found that in moderately weathered soils in seasonal climate zones with poorly crystalline and reactive clay minerals, organic carbon persists longer on average (topsoil: 201 ± 130 years; subsoil: 645 ± 385 years) than in highly weathered soils in humid regions (topsoil: 140 ± 46 years; subsoil: 454 ± 247 years) with less reactive minerals. Soils in arid climate zones (topsoil: 396 ± 339 years; subsoil: 963 ± 669 years) store organic carbon for periods more similar to those in seasonal climate zones, likely reflecting climatic constraints on weathering, carbon inputs and microbial decomposition. These insights into the timescales of organic carbon persistence in soils of sub-Saharan Africa suggest that a process-oriented grouping of soils based on pedo-climatic conditions may be useful to improve predictions of soil responses to climate change at broader scales.

KeywordsAfrican Soil Information Service; Afrotropics; Clay mineralogy; Climate change; Mean C age; Radiocarbon ; Subtropical
Year of Publication2024
JournalGlobal Change Biology
Journal citation30 (1), p. e17089
Digital Object Identifier (DOI)https://doi.org/10.1111/gcb.17089
Open accessPublished as ‘gold’ (paid) open access
FunderBiotechnology and Biological Sciences Research Council
Bill and Melinda Gates Foundation
European Research Council
Funder project or codeChemical and Biological Assessment of AfSIS soils
S2N - Soil to Nutrition - Work package 1 (WP1) - Optimising nutrient flows and pools in the soil-plant-biota system
Publisher's version
Output statusPublished
Publication dates
Online11 Dec 2023
Publication process dates
Accepted27 Nov 2023
PublisherWiley
ISSN1354-1013

Permalink - https://repository.rothamsted.ac.uk/item/98zz1/controls-on-timescales-of-soil-organic-carbon-persistence-across-sub-saharan-africa

14 total views
1 total downloads
3 views this month
1 downloads this month
Download files as zip