干旱区生态环境知识资源中心(Arid): Sensitivity of soil organic matter to climate and fire in a desert grassland

Arid

DOI	10.1007/s10533-020-00713-3
	Sensitivity of soil organic matter to climate and fire in a desert grassland
	Hou, Enqing; Rudgers, Jennifer A.; Collins, Scott L.; Litvak, Marcy E.; White, Carleton S.; Moore, Douglas I.; Luo, Yiqi
通讯作者	Hou, EQ
来源期刊	BIOGEOCHEMISTRY
ISSN	0168-2563
EISSN	1573-515X
英文摘要	Drylands contain a third of the organic carbon stored in global soils; however, the long-term dynamics of soil organic carbon in drylands remain poorly understood relative to dynamics of the vegetation carbon pool. We examined long-term patterns in soil organic matter (SOM) against both climate and prescribed fire in a Chihuahuan Desert grassland in central New Mexico, USA. SOM concentration was estimated by loss-on-ignition from soils at 0-20 cm depth each spring and fall for 25 years (1989-2014) in unburned desert grassland and from 2003 to 2014 following a prescribed fire. SOM concentration did not have a long-term trend but fluctuated seasonally at both burned and unburned sites, ranging from a minimum of 0.9% to a maximum of 3.3%. SOM concentration declined nonlinearly in wet seasons and peaked in dry seasons. These long-term results contrast not only with the positive relationships between aboveground net primary production and precipitation for this region, but also with previous reports that wetter sites have more SOM across drylands globally, suggesting that space is not a good substitute for time in predicting dryland SOM dynamics. We suggest that declines in SOM in wet periods are caused by increased soil respiration, runoff, leaching, and/or soil erosion. In addition to tracking natural variability in climate, SOM concentration also decreased 14% following prescribed fire, a response that magnified over time and has persisted for nearly a decade due to the slow recovery of primary production. Our results document the surprisingly dynamic nature of soil organic matter and its high sensitivity to climate and fire in a dry grassland ecosystem characteristic of the southwestern USA.
英文关键词	Soil organic matter Climate sensitivity function Climate variability Desert grassland Standardized Precipitation Evapotranspiration Index
类型	Article ; Early Access
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000587940700002
WOS关键词	NORTHERN CHIHUAHUAN DESERT ; TEMPORAL DYNAMICS ; SEMIARID ECOSYSTEMS ; LITTER DECOMPOSITION ; SEASONAL-VARIATION ; TURNOVER TIMES ; CO2 EFFLUX ; CARBON ; PRECIPITATION ; VARIABILITY
WOS类目	Environmental Sciences ; Geosciences, Multidisciplinary
WOS研究方向	Environmental Sciences & Ecology ; Geology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/328462
作者单位	[Hou, Enqing; Luo, Yiqi] No Arizona Univ, Dept Biol Sci, Ctr Ecosyst Sci & Soc, Box 5640, Flagstaff, AZ 86011 USA; [Rudgers, Jennifer A.; Collins, Scott L.; Litvak, Marcy E.; White, Carleton S.; Moore, Douglas I.] Univ New Mexico, Dept Biol, MSC03-2020, Albuquerque, NM 87131 USA
推荐引用方式 GB/T 7714	Hou, Enqing,Rudgers, Jennifer A.,Collins, Scott L.,et al. Sensitivity of soil organic matter to climate and fire in a desert grassland[J].
APA	Hou, Enqing.,Rudgers, Jennifer A..,Collins, Scott L..,Litvak, Marcy E..,White, Carleton S..,...&Luo, Yiqi.
MLA	Hou, Enqing,et al."Sensitivity of soil organic matter to climate and fire in a desert grassland".BIOGEOCHEMISTRY