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Soil organic carbon (SOC) is essential for the productivity of agroecosystems and for mitigating climate change. Because the SOC contents of sandy soils are usually small, the effects of agricultural management upon SOC stocks in such soils have been insufficiently studied. In West sub-arid Africa, the coarse-textured soils (mostly Arenosols) are diversely managed by smallholders. In this study, we aimed to quantify SOC stocks in cultivated soils of that region, in a context where agricultural practices rely mainly upon organic inputs derived from various integrated crop-livestock systems. SOC stocks were estimated for the 0–30 cm depth in 1,813 plots in Senegal’s groundnut basin. We found that SOC stocks in farmers’ fields varied between 2.3 and 59.8 Mg C ha-1 (mean ± standard deviation, 14.6 ± 0.14 Mg C ha-1). SOC stocks were influenced slightly by soil type, but were only weakly correlated to soils’ clay and silt contents. SOC stocks differed significantly among the three studied village territories due to contrasting livestock-raising systems. Average stocks were significantly higher in plots close to housings (home-fields), which receive larger amounts of organic inputs, than in plots farther from the village (out-fields). Thus, the organic inputs to home-fields improves soil C stocks of these sandy soils in the short term. Innovative agricultural practices in the studied area probably need to target options for managing all fields optimally. Those options will require continuous application of organic products—a measure that will in turn require solutions for improving availability or management of local organic resources.
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ORIGINAL ARTICLE
Estimates of carbon stocks in sandy soils cultivated under local
management practices in Senegals groundnut basin
Oscar Pascal Malou
1,2
&Patricia Moulin
1,3
&Tiphaine Chevallier
4
&Dominique Masse
4,5
&Jonathan Vayssières
1,6,7,8
&
Ndèye Yacine Badiane-Ndour
1,9,10
&Laure Tall
1,9
&Abou Thiam
2
&Lydie Chapuis-Lardy
1,4
Received: 30 June 2020 / Accepted: 14 May 2021
#The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2021
Abstract
Soil organic carbon (SOC) is essential for the productivity of agroecosystems and for mitigating climate change.
Because the SOC contents of sandy soils are usually small, the effects of agricultural management upon SOC stocks
in such soils have been insufficiently studied. In West sub-arid Africa, the coarse-textured soils (mostly Arenosols) are
diversely managed by smallholders. In this study, we aimed to quantify SOC stocks in cultivated soils of that region, in a
context where agricultural practices rely mainly upon organic inputs derived from various integrated crop-livestock
systems. SOC stocks were estimated for the 030 cm depth in 1,813 plots in Senegals groundnut basin. We found
that SOC stocks in farmersfields varied between 2.3 and 59.8 Mg C ha
-1
(mean ± standard deviation, 14.6 ± 0.14 Mg C
ha
-1
). SOC stocks were influenced slightly by soil type, but were only weakly correlated to soilsclay and silt contents.
SOC stocks differed significantly among the three studied village territories due to contrasting livestock-raising systems.
Average stocks were significantly higher in plots close to housings (home-fields), which receive larger amounts of
organic inputs, than in plots farther from the village (out-fields). Thus, the organic inputs to home-fields improves soil
C stocks of these sandy soils in the short term. Innovative agricultural practices in the studied area probably need to
target options for managing all fields optimally. Those options will require continuous application of organic products
a measure that will in turn require solutions for improving availability or management of local organic resources.
Keywords Soil organic carbon (SOC) .SOC stocks .West Africa .Organic input .Coarse texture .Visible near-infrared
spectroscopy
This article is part of the Topical Collection on Regional management
practices with positive effects on soil carbon to meet the goals of the
4p1000 initiative
Communicated by Lydie-Stella Koutika and accepted by Topical
Collection Chief Editor Christopher Reyer
*Oscar Pascal Malou
opmalou@gmail.com
1
LMIIESOL,Dakar,Senegal
2
University Cheikh Anta Diop, Institute of Environmental Sciences,
Dakar, Senegal
3
IRD, IMAGO LAMA, Dakar, Senegal
4
IRD, Eco&Sols, University of Montpellier, CIRAD, INRAE, IRD,
Institut Agro, Montpellier, France
5
IRD, Eco&Sols, Abidjan, Ivory Coast
6
CIRAD, UMR SELMET, Montpellier, France
7
SELMET, University of Montpellier, CIRAD, INRAE, IRD, Institut
Agro, Montpellier, France
8
PPZS,Dakar,Senegal
9
ISRA, LNRPV, Dakar, Senegal
10
Present address: FAO Regional Office, Dakar, Senegal
https://doi.org/10.1007/s10113-021-01790-2
/ Published online: 8 June 2021
Regional Environmental Change (2021) 21: 65
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
ResearchGate has not been able to resolve any citations for this publication.
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