气候变化领域集成服务门户(CCPortal): Microbial abundances and carbon use under ambient temperature or experimental warming in a southern boreal peatland

CCPortal

DOI	10.1007/s10533-024-01129-z
	Microbial abundances and carbon use under ambient temperature or experimental warming in a southern boreal peatland
	Felice, Mark; Blake, Cameron M.; Sebestyen, Stephen; Gutknecht, Jessica L. M.
发表日期	2024
ISSN	0168-2563
EISSN	1573-515X
起始页码	167
结束页码	5
卷号	167 期号:5
英文摘要	Organic peat soils occupy relatively little of the global land surface area but store vast amounts of soil carbon in northern latitudes where climate is warming at a rapid pace. Warming may result in strong positive feedbacks of carbon loss and global climate change driven by microbial processes if warming alters the balance between primary productivity and decomposition. To elucidate effects of warming on the microbial communities mediating peat carbon dynamics, we explored the abundance of broad microbial groups and their source of carbon (i.e. old carbon versus more recently fixed photosynthate) using microbial lipid analysis (delta 13C PLFA) of peat samples under ambient temperatures and before/after initiation of experimental peat warming (+ 2.25, + 4.5, + 6.75, and + 9 degree celsius). This analysis occurred over a profile to 2 m depth in an undrained, ombrotrophic peat bog in northern Minnesota. We found that the total microbial biomass and individual indicator lipid abundances were stratified by depth and strongly correlated to temperature under ambient conditions. However, under experimental warming, statistically significant effects of temperature on the microbial community were sporadic and inconsistent. For example, 3 months after experimental warming the relative abundance of Gram-negative bacterial indicators across depth combined and > 50 cm depth and Gram-positive bacterial indicators at 20-50 cm depth showed significant positive relationships to temperature. At that same timepoint, however, the relative abundance of Actinobacterial indicators across depth showed a significant negative relationship to temperature. After 10 months of experimental warming, the relative abundance of fungal biomarkers was positively related to temperature in all depths combined, and the absolute abundance of anaerobic bacteria declined with increasing temperature in the 20-50 cm depth interval. The lack of observed response in the broader microbial community may suggest that at least initially, microbial community structure with peat depth in these peatlands is driven more by bulk density and soil water content than temperature. Alternatively, the lack of broad microbial community response may simply represent a lag period, with more change to come in the future. The long-term trajectory of microbial response to warming in this ecosystem then could either be direct, after this initial lag time, or indirect through other physical or biogeochemical changes in the peat profile. These initial results provide an important baseline against which to measure long-term microbial community and carbon-cycling responses to warming and elevated CO2.
英文关键词	delta C-13 PLFA; Boreal peatland; Microbial communities; Climate change; Carbon
语种	英语
WOS研究方向	Environmental Sciences & Ecology ; Geology
WOS类目	Environmental Sciences ; Geosciences, Multidisciplinary
WOS记录号	WOS:001190340500002
来源期刊	BIOGEOCHEMISTRY
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/293029
作者单位	University of Minnesota System; University of Minnesota Twin Cities; United States Department of Agriculture (USDA); United States Forest Service
推荐引用方式 GB/T 7714	Felice, Mark,Blake, Cameron M.,Sebestyen, Stephen,et al. Microbial abundances and carbon use under ambient temperature or experimental warming in a southern boreal peatland[J],2024,167(5).
APA	Felice, Mark,Blake, Cameron M.,Sebestyen, Stephen,&Gutknecht, Jessica L. M..(2024).Microbial abundances and carbon use under ambient temperature or experimental warming in a southern boreal peatland.BIOGEOCHEMISTRY,167(5).
MLA	Felice, Mark,et al."Microbial abundances and carbon use under ambient temperature or experimental warming in a southern boreal peatland".BIOGEOCHEMISTRY 167.5(2024).