干旱区生态环境知识资源中心(Arid): Cross-rangeland comparisons on soil carbon dynamics in the pedoderm of semi-arid and arid South African commercial farms

Arid

DOI	10.1016/j.geoderma.2020.114689
	Cross-rangeland comparisons on soil carbon dynamics in the pedoderm of semi-arid and arid South African commercial farms
	Loke, Palo Francis; Kotze, Elmarie; Du Preez, Christiaan Cornelius; Twigge, Linette
通讯作者	Loke, PF
来源期刊	GEODERMA
ISSN	0016-7061
EISSN	1872-6259
出版年	2021
卷号	381
英文摘要	The increase of carbon (C) in the pedoderm (0-50 mm soil layer) improves ecosystem functioning and stability. This study evaluated quantitative and qualitative C responses to grazing intensity in the pedoderm of grassland and savanna ecosystems. These ecosystems differ in terms of soil properties, climate, vegetation quality and livestock density. Three commercial farms were chosen from each ecosystem. Each farm exhibited two grazing intensities (heavy and light grazing) by livestock which induced poor and good forage quality, respectively. Vegetation quality changes were observed along a gradient of grazing pressure, with respect to the distance from the water point. Soil samples of the pedoderm were taken in each of the two zones to analyse the effects of grazing on soil quality parameters. Soil samples were analyzed for soil organic carbon (SOC), soil inorganic carbon (SIC), labile and humic C fractions. The SOC structure was determined with C-13 NMR spectroscopy. Indices of the extent of SOC decomposition were calculated. Grazing pressure per se did not influence soil C fractions. However, clayey grassland soils in the cool-moist climate exhibited more resilience to C losses than sandy savanna soils under hot-dry climatic conditions. Thus, comparisons between the two ecosystems showed that on average, all C fractions were 35-97% higher in the clayey moist-cool grassland ecosystem compared to the sandy dry-hot savanna ecosystem, regardless of the grazing pressure. A decline in O-alkyl C (7%) with concomitant increase in recalcitrant alkyl C (6%) in the grassland ecosystem, indicated that constant animal trampling induced SOC decomposition, and loss of labile C fractions in the heavily grazed zones. Molecular composition of SOC in the savanna ecosystem was more influenced by plant functional types, thus C allocation patterns, than decomposition.
英文关键词	C-13 NMR spectroscopy Clay content Climate Grazing gradient Rangeland ecosystems Soil carbon fractions
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000582381600008
WOS关键词	MACROMOLECULAR ORGANIC COMPOSITION ; N-15 NMR-SPECTROSCOPY ; MICROBIAL RESIDUES ; MANAGEMENT IMPACTS ; GRAZING GRADIENTS ; INORGANIC CARBON ; MIXED-GRASS ; C-13 ; SEQUESTRATION ; NITROGEN
WOS类目	Soil Science
WOS研究方向	Agriculture
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/327942
作者单位	[Loke, Palo Francis; Kotze, Elmarie; Du Preez, Christiaan Cornelius] Univ Free State, Dept Soil Crop & Climate Sci, POB 339, ZA-9300 Bloemfontein, South Africa; [Twigge, Linette] Univ Free State, Dept Chem, POB 339, ZA-9300 Bloemfontein, South Africa
推荐引用方式 GB/T 7714	Loke, Palo Francis,Kotze, Elmarie,Du Preez, Christiaan Cornelius,et al. Cross-rangeland comparisons on soil carbon dynamics in the pedoderm of semi-arid and arid South African commercial farms[J],2021,381.
APA	Loke, Palo Francis,Kotze, Elmarie,Du Preez, Christiaan Cornelius,&Twigge, Linette.(2021).Cross-rangeland comparisons on soil carbon dynamics in the pedoderm of semi-arid and arid South African commercial farms.GEODERMA,381.
MLA	Loke, Palo Francis,et al."Cross-rangeland comparisons on soil carbon dynamics in the pedoderm of semi-arid and arid South African commercial farms".GEODERMA 381(2021).