Controls on timescales of soil organic carbon persistence across sub-Saharan Africa.
Glob Chang Biol
; 30(1): e17089, 2024 Jan.
Article
em En
| MEDLINE
| ID: mdl-38273490
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.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Solo
/
Carbono
Tipo de estudo:
Prognostic_studies
País/Região como assunto:
Africa
Idioma:
En
Revista:
Glob Chang Biol
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Alemanha