Cultivation-induced effects on the organic matter in degraded Southern African soils
2012
Pardo Fernández, María Teresa | Almendros Martín, Gonzalo | Zancada Fernández, M. Cristina | López-Fando, Cristina | González-Vila, Francisco Javier
15 pages, 5 figures, 2 tables, 38 references.
显示更多 [+] 显示较少 [-]We studied quantitative and qualitative changes in soil organic matter (SOM) due to different land uses (reference woodland versus cultivated) on six soils from Tanzania (Mkindo and Mafiga), Zimbabwe (Domboshawa and Chickwaka), and South Africa (Hertzog and Guquka). Structural characteristics of the humic acids (HAs) were measured by Curie-point pyrolysis-gas chromatography/mass spectrometry (P y-GC/MS) and solid-state 13C nuclear magnetic resonance (CPMAS 13C NMR) spectroscopy. Significant changes in concentration and composition of SOM were observed between land uses. Losses of organic carbon after cultivation ranged from 35% to 50%. Virgin soils showed large proportions of colloidal humus fractions: humic acids (HAs) and fulvic acids (FAs) but negligible amounts of not-yet decomposed organic residues. The change in land use produced a contrasting effect on the composition of the HAs: a noteworthy >alkyl enhancement> in Mkindo soil and >alkyl depletion> in Chikwaka and to a lesser extent in Domwoshawa. The remaining soils displayed only minor alterations.
显示更多 [+] 显示较少 [-]This work was part of an EU INCO-DEV-funded research program in southern Africa (Cyanosoils), Project ICA-4-CT-2001-10058.
显示更多 [+] 显示较少 [-]Peer Reviewed
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