Show simple item record

dc.contributor.authorVenter, Zander
dc.contributor.authorHawkins, Heidi-Jayne
dc.contributor.authorCramer, Michael D.
dc.contributor.authorMills, Anthony J.
dc.coverage.spatialSouth Africaen_US
dc.identifier.citationScience of the Total Environment. 2021, 771 1-14.en_US
dc.description.abstractEstimation and monitoring of soil organic carbon (SOC) stocks is important for maintaining soil productivity and meeting climate change mitigation targets. Current global SOC maps do not provide enough detail for landscape- scale decision making, and do not allow for tracking carbon sequestration or loss over time. Using an optical satellite-driven machine learning workflow, we mapped SOC stocks (topsoil; 0 to 30 cm) under natural vegeta- tion (86% of land area) over South Africa at 30 m spatial resolution between 1984 and 2019. We estimate a total topsoil SOC stock of 5.6 Pg C with a median SOC density of 6 kg C m−2 (IQR: interquartile range 2.9 kg C m−2). Over 35 years, predicted SOC underwent a net increase of 0.3% (relative to long-term mean) with the greatest net increases (1.7%) and decreases (−0.6%) occurring in the Grassland and Nama Karoo biomes, respectively. At the landscape scale, SOC changes of up to 25% were evident in some locations, as evidenced from fence-line contrasts, and were likely due to local management effects (e.g. woody encroachment associated with increased SOC and overgrazing associated with decreased SOC). Our SOC mapping approach exhibited lower uncertainty (R2 = 0.64; RMSE = 2.5 kg C m−2) and less bias compared to previous low-resolution (250–1000 m) national SOC mapping efforts (average R2 = 0.24; RMSE = 3.7 kg C m−2). Our trend map remains an estimate, pending repeated measures of soil samples in the same location (time-series); a global priority for tracking SOC changes. While high resolution SOC maps can inform land management decisions aimed at climate mitigation (natural cli- mate solutions), potential increases in SOC are likely limited by local climate and soils. It is also important that climate mitigation efforts such as planting trees balance trade-offs between car Carbon stocks Land degradation Natural climate solutions Remote sensing Soil mapping Spatial predictionbon, biodiversity and overall eco- system functionen_US
dc.rightsNavngivelse 4.0 Internasjonal*
dc.subjectCarbon stocksen_US
dc.subjectLand degradationen_US
dc.subjectNatural climate solutionsen_US
dc.subjectRemote sensingen_US
dc.subjectSoil mappingen_US
dc.subjectSpatial predictionen_US
dc.titleMapping soil organic carbon stocks and trends with satellite-driven high resolution maps over South Africaen_US
dc.typePeer revieweden_US
dc.typeJournal articleen_US
dc.rights.holder© 2021 The Author(s)en_US
dc.subject.nsiVDP::Samfunnsvitenskap: 200en_US
dc.subject.nsiVDP::Social sciences: 200en_US
dc.source.journalScience of the Total Environmenten_US
dc.relation.projectAndre: National Research Foundationen_US
dc.relation.projectAndre: Patterson Foundationen_US

Files in this item


This item appears in the following Collection(s)

Show simple item record

Navngivelse 4.0 Internasjonal
Except where otherwise noted, this item's license is described as Navngivelse 4.0 Internasjonal