干旱区生态环境知识资源中心(Arid): Plant community change mediated heterotrophic respiration increase explains soil organic carbon loss before moderate degradation of alpine meadow

Arid

DOI	10.1002/ldr.4111
	Plant community change mediated heterotrophic respiration increase explains soil organic carbon loss before moderate degradation of alpine meadow
	Lai, Chimin; Li, Chengyang; Peng, Fei; Xue, Xian; You, Quangang; Zhang, Wenjuan; Ma, Shaoxiu
通讯作者	Peng, F (corresponding author), Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, 320 Donggang West Rd, Lanzhou 730000, Gansu, Peoples R China.
来源期刊	LAND DEGRADATION & DEVELOPMENT
ISSN	1085-3278
EISSN	1099-145X
出版年	2021
英文摘要	Alpine meadows on the Qinghai-Tibet Plateau (QTP) store a huge amount of plant and soil carbon (C). The degradation of the alpine meadow has led to a significant loss of soil organic C (SOC), which endangers its weak C sink. The change in heterotrophic respiration was hypothesized as one of the primary biological processes for the SOC loss alongside the degradation of alpine meadow. However, little is known about how land degradation impacts R-h due to changes in plant communities and consequent labile organic C inputs. R-h, vegetation productivity, plant community composition, plant lignin concentration, leaf C/N, SOC, and soil labile C (SLC) were measured for alpine meadow grasslands with five degradation levels in 2 years. Our results showed that the SOC of the surface layer (0-10 cm) gradually decreased with land degradation. The plant lignin concentration and C/N ratio gradually increased with land degradation due to the proportion of sedges decreased while that of forbs increased, which consequently led to the soil C quality (SLC) increased before the moderate degradation level (MD) while significantly reduced in severe and very severe degradation levels (SD and VSD). The structural equation modeling result (SEM) revealed that the degradation-induced change in soil C quality (SLC) due to an alteration in plant community composition relates to the R-h change with grassland degradation, and the R-h (C output) and aboveground biomass (AGB: C input) further mediated the loss of SOC alongside alpine meadow degradation. On average, R-h increased by 49% and 59% from the Intact to slight degradation level (SLD) and MD and reduced by 56% and 69% from MD to SD and VSD. The temperature sensitivity of R-h (Q(10)) was higher in the SLD (Q(10) = 2.84) and MD (Q(10) = 2.62) comparing with the Intact (Q(10) = 2.58) respectively, but it was lower in SD (Q(10) = 2.19) and VSD (Q(10) = 1.65). AGB and belowground net primary productivity (BNPP) had no significant change until the MD, while reduced by 60%-90% in SD and VSD. Our results suggest that R-h and its Q(10) change moderated by soil C quality alteration due to the plant community shifting could be one mechanism for the soil C loss before MD, but could not be the main pathway for the SOC loss at SD and VSD.
英文关键词	cold-arid regions grassland degradation soil labile carbon soil respiration temperature sensitivity
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000707194500001
WOS关键词	QINGHAI-TIBETAN PLATEAU ; TEMPERATURE SENSITIVITY ; GRASSLAND DEGRADATION ; MICROBIAL RESPIRATION ; MATTER DECOMPOSITION ; NITROGEN ADDITION ; LITTER ; RESPONSES ; ECOSYSTEM ; BIOMASS
WOS类目	Environmental Sciences ; Soil Science
WOS研究方向	Environmental Sciences & Ecology ; Agriculture
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/364109
作者单位	[Lai, Chimin; Li, Chengyang; Peng, Fei; Xue, Xian; You, Quangang; Ma, Shaoxiu] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Desert & Desertificat, 320 Donggang West Rd, Lanzhou 730000, Gansu, Peoples R China; [Lai, Chimin; Li, Chengyang] Univ Chinese Acad Sci, Coll Resources & Environm, Beijing, Peoples R China; [Peng, Fei] Tottori Univ, Int Platform Dryland Res & Educ, Tottori, Japan; [Zhang, Wenjuan] Lanzhou Univ Arts & Sci, Sch Tourism, Lanzhou, Peoples R China
推荐引用方式 GB/T 7714	Lai, Chimin,Li, Chengyang,Peng, Fei,et al. Plant community change mediated heterotrophic respiration increase explains soil organic carbon loss before moderate degradation of alpine meadow[J],2021.
APA	Lai, Chimin.,Li, Chengyang.,Peng, Fei.,Xue, Xian.,You, Quangang.,...&Ma, Shaoxiu.(2021).Plant community change mediated heterotrophic respiration increase explains soil organic carbon loss before moderate degradation of alpine meadow.LAND DEGRADATION & DEVELOPMENT.
MLA	Lai, Chimin,et al."Plant community change mediated heterotrophic respiration increase explains soil organic carbon loss before moderate degradation of alpine meadow".LAND DEGRADATION & DEVELOPMENT (2021).