干旱区生态环境知识资源中心(Arid): Non-rainfall Moisture: A Key Driver of Microbial Respiration from Standing Litter in Arid, Semiarid, and Mesic Grasslands

Arid

DOI	10.1007/s10021-019-00461-y
	Non-rainfall Moisture: A Key Driver of Microbial Respiration from Standing Litter in Arid, Semiarid, and Mesic Grasslands
	Evans, Sarah 1,6; Todd-Brown, Katherine E. O.2,3,4; Jacobson, Kathryn 5; Jacobson, Peter 5
通讯作者	Evans, Sarah
来源期刊	ECOSYSTEMS
ISSN	1432-9840
EISSN	1435-0629
出版年	2020
卷号	23 期号:6 页码:1154-1169
英文摘要	Models assume that rainfall is the major moisture source driving decomposition. Non-rainfall moisture (NRM: high humidity, dew, and fog) can also induce standing litter decomposition, but there have been few measurements of NRM-mediated decomposition across sites and no efforts to extrapolate the contribution of NRM to larger scales to assess whether this mechanism can improve model predictions. Here, we show that NRM is an important, year-round source of moisture in grassland sites with contrasting moisture regimes using field measurements and modeling. We first characterized NRM frequency and measured NRM-mediated decomposition at two sites in the Namib Desert, Namibia (hyper-arid desert), and at one site in Iowa, USA (tallgrass prairie). NRM was frequent at all sites (85-99% of hours that litter was likely to be wet were attributed to NRM) and tended to occur in cool, high-humidity periods for several hours or more at a time. NRM also resulted in CO2 release from microbes in standing litter at all sites when litter became sufficiently wet (> 5% gravimetric moisture for fine litter and > 13% for coarse), and significantly contributed to mass loss, particularly in the western Namib site that received almost no rain. When we modeled annual mass loss induced by NRM and rain and extrapolated our characterization of NRM decomposition to a final semiarid site (Sevilleta, New Mexico), we found that models driven by rainfall alone underestimated mass loss, while including NRM resulted in estimates within the range of observed mass loss. Together these findings suggest that NRM is an important missing component in quantitative and conceptual models of litter decomposition, but there is nuance involved in modeling NRM at larger scales.Specifically, temperature and physical features of the substrate emerge as factors that affect the microbial response to litter wetting under NRM in our sites, and require further study. Hourly humidity can provide an adequate proxy of NRM frequency, but site-specific calibration with litter wetness is needed to accurately attribute decomposition to periods when NRM wets litter. Greater recognition of NRM-driven decomposition and its interaction with other processes like photodegradation is needed, especially since fog, dew, and humidity are likely to shift under future climates.
英文关键词	fog dew non-rainfall moisture (NRM) standing litter microbial decomposition drylands semiarid mesic modeling
类型	Article
语种	英语
国家	USA ; Canada
开放获取类型	hybrid
收录类别	SCI-E
WOS记录号	WOS:000501360900003
WOS关键词	PLANT LITTER ; RELATIVE-HUMIDITY ; SURFACE LITTER ; CLIMATE-CHANGE ; DECOMPOSITION ; PHOTODEGRADATION ; ECOSYSTEM ; PATTERNS ; RELEASE ; DRY
WOS类目	Ecology
WOS研究方向	Environmental Sciences & Ecology
EI主题词	2019-12-02
来源机构	Colorado State University
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/311529
作者单位	1.Michigan State Univ, Kellogg Biol Stn, Ecol Evolutionary Biol & Behav Program, Dept Integrat Biol,Dept Microbiol & Mol Genet, Hickory Corners, MI 49060 USA; 2.Pacific Northwest Natl Lab, Richland, WA 99352 USA; 3.Wilfred Laurier Univ, Waterloo, ON, Canada; 4.Univ Florida, Engn Sch Sustainable Infrastruct & Environm, Gainesville, FL USA; 5.Grinnell Coll, Dept Biol, Grinnell, IA 50112 USA; 6.Colorado State Univ, Nat Resource Ecol Lab, Campus Delivery 1499, Ft Collins, CO 80523 USA
推荐引用方式 GB/T 7714	Evans, Sarah,Todd-Brown, Katherine E. O.,Jacobson, Kathryn,et al. Non-rainfall Moisture: A Key Driver of Microbial Respiration from Standing Litter in Arid, Semiarid, and Mesic Grasslands[J]. Colorado State University,2020,23(6):1154-1169.
APA	Evans, Sarah,Todd-Brown, Katherine E. O.,Jacobson, Kathryn,&Jacobson, Peter.(2020).Non-rainfall Moisture: A Key Driver of Microbial Respiration from Standing Litter in Arid, Semiarid, and Mesic Grasslands.ECOSYSTEMS,23(6),1154-1169.
MLA	Evans, Sarah,et al."Non-rainfall Moisture: A Key Driver of Microbial Respiration from Standing Litter in Arid, Semiarid, and Mesic Grasslands".ECOSYSTEMS 23.6(2020):1154-1169.