干旱区生态环境知识资源中心(Arid): Moss biocrusts regulate surface soil thermal properties and generate buffering effects on soil temperature dynamics in dryland ecosystem

Arid

DOI	10.1016/j.geoderma.2019.05.017
	Moss biocrusts regulate surface soil thermal properties and generate buffering effects on soil temperature dynamics in dryland ecosystem
	Xiao, Bo 1,2; Ma, Shuang 1; Hu, Kelin 1,2
通讯作者	Xiao, Bo
来源期刊	GEODERMA
ISSN	0016-7061
EISSN	1872-6259
出版年	2019
卷号	351 页码:9-24
英文摘要	Biocrusts are promising ecosystem engineers in dryland ecosystems, but their effects on soil temperature, which is the most important environmental factor of soil biological and biochemical processes, have not yet been well understood. In a semiarid ecosystem on the Chinese Loess Plateau, the thermal properties of moss-dominated biocrust layer and bare soil (upper 2 cm) were measured, and their correlations with the biocrust characteristics as well as soil properties (especially soil water content, theta) were analyzed. Afterwards, the soil temperature dynamics of the biocrust covered soil and bare soil were continuously recorded at 2, 6, and 10 cm depths during a year. From in-situ measurements in wet season, we found that the biocrusts increased surface soil heat capacity (C) by 10.3% (1.42 vs. 1.28 MJ m(-3) K-1), thermal conductivity (lambda) by 27.7% (0.69 vs. 0.54 W m(-1) K-1), and thermal diffusivity (alpha) by 27.9% (5.01 vs. 3.92 x 10(-7) m(2) s(-1)) as compared with the bare soil, through holding more soil water (theta of the biocrusts vs. bare soil = 0.06 vs. 0.03 cm(3) cm(-3)). However, in dry season (theta < 0.05 cm(3) cm(-3)) they decreased 33.4% of surface soil C (0.78 vs. 1.17 MJ m(-3) K-1), 54.9% of lambda (0.17 vs. 0.37 W m(-1) K-1), and 22.9% of a (2.32 vs. 3.01 x 10(-7) m(2) s(-1)) mostly by decreasing surface soil bulk density. Accordingly, the biocrusts decreased soil temperature by as much as 6.3-11.1 degrees C at 0-10 cm depth in wet season (summer), and they increased soil temperature by up to 1.3-3.7 degrees C in dry season (winter). More importantly, the diurnal range of soil temperature of the biocrust covered soil was sometimes as much as 6.8-9.4 degrees C lower than that of the bare soil at 0-10 cm depth. The decreasing or increasing effects of the biocrusts on soil temperature were exactly explained by the increased thermal properties of the biocrust layer in wet season or reduced thermal properties of the biocrust layer in dry season. We concluded that the biocrusts regulated surface soil thermal properties through increasing soil water holding capacity and decreasing soil bulk density; thus, they generated considerable buffering effects on soil temperature dynamics. In dryland ecosystem, such buffering effects of the biocrusts on soil temperature should be highly considered in various soil biological and biochemical processes.
英文关键词	Microbiotic crust Biological soil crust Heat capacity Thermal conductivity Thermal diffusivity Heat pulse probe
类型	Article
语种	英语
国家	Peoples R China
收录类别	SCI-E
WOS记录号	WOS:000474495700002
WOS关键词	SAND DUNES ; LOESS PLATEAU ; CRUSTS ; MOISTURE ; WATER ; DESERT ; CONDUCTIVITY ; EVAPORATION ; DENSITY ; CHINA
WOS类目	Soil Science
WOS研究方向	Agriculture
来源机构	中国农业大学
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/215938
作者单位	1.China Agr Univ, Coll Resources & Environm Sci, 2 Yuanmingyuan West Rd, Beijing 100193, Peoples R China; 2.Minist Agr, Key Lab Arable Land Conservat North China, Beijing 100193, Peoples R China
推荐引用方式 GB/T 7714	Xiao, Bo,Ma, Shuang,Hu, Kelin. Moss biocrusts regulate surface soil thermal properties and generate buffering effects on soil temperature dynamics in dryland ecosystem[J]. 中国农业大学,2019,351:9-24.
APA	Xiao, Bo,Ma, Shuang,&Hu, Kelin.(2019).Moss biocrusts regulate surface soil thermal properties and generate buffering effects on soil temperature dynamics in dryland ecosystem.GEODERMA,351,9-24.
MLA	Xiao, Bo,et al."Moss biocrusts regulate surface soil thermal properties and generate buffering effects on soil temperature dynamics in dryland ecosystem".GEODERMA 351(2019):9-24.