Applying biochar under topsoil facilitates soil carbon sequestration: A case study in a dryland agricultural system on the Loess Plateau

doi:10.1016/j.geoderma.2021.115186

	Applying biochar under topsoil facilitates soil carbon sequestration: A case study in a dryland agricultural system on the Loess Plateau
	Li, Shuailin 1,2; Ma, Qiang 2; Zhou, Changrui 2,3; Yu, Wantai 2; Shangguan, Zhouping 1
刊名	GEODERMA
	2021-12-01
卷号	403 页码:13
关键词	Biochar application depth Soil respiration Methane uptake Metabolic quotient (qCO(2)) Temperature sensitivity (Q(10))
ISSN号	0016-7061
DOI	10.1016/j.geoderma.2021.115186
通讯作者	Yu, Wantai(wtyu@iac.cn) ; Shangguan, Zhouping(shangguan@ms-iswc.ac.cn)
英文摘要	The remarkable soil carbon sequestration and greenhouse gas mitigation effects of biochar have spurred great interest in exploring ways to maximize its benefits. However, it remains unclear how biochar application depth impacts soil carbon dioxide (CO2) emissions and methane (CH4) uptake in upland soil. Therefore, we carried out a 16-month field experiment in a dryland agricultural system to answer the above questions. Woody biochar (20 t ha(-1)) was mixed into three soil layers: 0-10 cm (BC0-10cm)(,) 10-20 cm (BC10-20cm), and 0-20 cm (BC0-20cm). Soil without biochar addition was used as the control (CK). We monitored soil CO2 and CH4 fluxes continuously and determined the metabolic quotient (qCO(2)) and the sensitivity of soil respiration to temperature (Q(10)). The results indicated that CO2 emissions, CH4 uptake, qCO(2) and Q(10) were significantly affected by biochar application depth. Overall, compared with CK, BC0-10cm increased total CO2 emissions by 10.13%, while BC10-20cm and BC0-20cm showed no significant effect. BC0-10cm and BC0-20cm exhibited greater soil CH4 uptake enhancement than BC10-20cm, but the enhanced CH4 uptake resulted in limited net greenhouse gas mitigation. BC10-20cm and BC0-20cm had a lower qCO(2) than the other treatments, which likely increased the carbon use efficiency and decreased the stress on soil microbes, but BC0-10cm showed the opposite effect. In addition, BC0-10cm significantly reduced Q(10) mainly due to the enhanced lability of the native carbon and microbial activities. Changes in environmental factors in the 0-10 cm soil largely explained the variations in CO2 emissions, CH4 uptake and Q(10) (>88%). Nevertheless, the enhanced microbial biomass in the 10-20 cm soil helped lower qCO(2) in the whole 0-20 cm layer. In summary, adding biochar to surface soil (0-10 cm) likely accelerates carbon loss, due to the strong shift in the environment of the surface soil caused by complex interactions among hydrothermal conditions, nutrient levels (i.e., N, NH4+, NO3 and available P) and labile carbon. However, adding biochar to subsurface soil (10-20 cm) can effectively avoid severe disturbance of the surface soil environment and thus benefit soil carbon sequestration in the long term.
资助项目	National Natural Science Foundation of China[42077452] ; National Natural Science Foundation of China[32001212]
WOS关键词	GREENHOUSE-GAS EMISSIONS ; TEMPERATURE SENSITIVITY ; MICROBIAL BIOMASS ; ORGANIC-MATTER ; HYDRAULIC CONDUCTIVITY ; DIFFERENT STABILITIES ; CO2 EFFLUX ; DECOMPOSITION ; RESPIRATION ; NITROGEN
WOS研究方向	Agriculture
语种	英语
出版者	ELSEVIER
WOS记录号	WOS:000671591200004
资助机构	National Natural Science Foundation of China
内容类型	期刊论文
源URL	[http://ir.igsnrr.ac.cn/handle/311030/163827]
专题	中国科学院地理科学与资源研究所
通讯作者	Yu, Wantai; Shangguan, Zhouping
作者单位	1.Chinese Acad Sci & Minist Water Resources, State Key Lab Soil Eros & Dryland Farming Loess P, Inst Soil & Water Conservat, Xian 712100, Shaanxi, Peoples R China 2.Chinese Acad Sci, Inst Appl Ecol, Shenyang 110016, Peoples R China 3.Univ Chinese Acad Sci, Beijing 100049, Peoples R China
推荐引用方式 GB/T 7714	Li, Shuailin,Ma, Qiang,Zhou, Changrui,et al. Applying biochar under topsoil facilitates soil carbon sequestration: A case study in a dryland agricultural system on the Loess Plateau[J]. GEODERMA,2021,403:13.
APA	Li, Shuailin,Ma, Qiang,Zhou, Changrui,Yu, Wantai,&Shangguan, Zhouping.(2021).Applying biochar under topsoil facilitates soil carbon sequestration: A case study in a dryland agricultural system on the Loess Plateau.GEODERMA,403,13.
MLA	Li, Shuailin,et al."Applying biochar under topsoil facilitates soil carbon sequestration: A case study in a dryland agricultural system on the Loess Plateau".GEODERMA 403(2021):13.