干旱区生态环境知识资源中心(Arid): Nonlinear response of hydrodynamic and soil erosive behaviors to biocrust coverage in drylands

Arid

DOI	10.1016/j.geoderma.2021.115457
	Nonlinear response of hydrodynamic and soil erosive behaviors to biocrust coverage in drylands
	Yang, Kai; Zhao, Yunge; Gao, Liqian; Sun, Hui; Gu, Kangmin
通讯作者	Zhao, YG (corresponding author), Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China.
来源期刊	GEODERMA
ISSN	0016-7061
EISSN	1872-6259
出版年	2022
卷号	405
英文摘要	In dryland ecosystems, soil erosion poses severe threats to ecosystem productivity and human well-being. Biological soil crusts (biocrusts) are ubiquitous living covers in these ecosystems and play an important role in soil stabilization and erosion prevention. However, the quantitative relationship between biocrust coverage and soil water erosion as well as the driving mechanism have not yet been fully discussed, which hinders the development of soil erosion models that consider the effect of biocrusts. Accordingly, we set up 19 biocrust plots (10 m x 2.1 m) with coverage ranging from 9.3% to 80.0% on the Loess Plateau of China and conducted a series of simulated rainfall experiments. The quantitative relationship between runoff and sediment yield and biocrust coverage was assessed, and further complex correlations among these variables were analyzed using structural equation modeling (SEM). We found that (1) the runoff rates and sediment yield were significantly related to biocrust coverage. The runoff rates and sediment yield decreased with increasing biocrust coverage via a logarithmic function and an exponential function, respectively. The runoff rate and sediment yield rate from the plot with 9.3% biocrust coverage were 3.2 and 51.5 times higher, respectively, than those from the plot with 78.4% biocrust coverage. (2) The flow pattern and regime of overland flow were significantly affected by biocrust coverage. The overland flow was shifted from tranquil flow to supercritical flow when the biocrust coverage declined to 12.3%. The flow velocity, stream power, Darcy-Weisbach resistance coefficient, Froude number, and Reynolds number were strongly correlated with biocrust coverage (R-2 = 0.548-0.830). (3) Biocrust coverage both directly and indirectly affected sediment yield. The anchoring effect of biocrusts directly protected the surface soil from raindrop impacts and runoff scouring (direct effect = -0.59). Additionally, biocrust cover had an indirect negative effect (-0.38) on sediment yield by decreasing the flow velocity and runoff rate with path coefficients of -0.81 and -0.78, respectively. Our results confirm that soil hydrological and erosive behavior have nonlinear relationships with biocrust coverage at the hill-slope scale, and they also reveal that variation in biocrust coverage is one of the main driving factors affecting soil hydrological and erosive behaviors. These results would improve soil water erosion estimation on biocrust-covered slopes and provide guidance for revising soil erosion models to include the effectiveness of biocrusts.
英文关键词	Biological soil crust Soil erosion Runoff Hydrodynamic parameters
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000703712100040
WOS关键词	HILLY LOESS PLATEAU ; SURFACE-ROUGHNESS ; NEGEV DESERT ; NATURAL SUCCESSION ; WATER INFILTRATION ; MICROBIOTIC CRUST ; DUNE SLOPES ; RUNOFF ; SCALE ; REGION
WOS类目	Soil Science
WOS研究方向	Agriculture
来源机构	西北农林科技大学
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/363395
作者单位	[Yang, Kai; Gu, Kangmin] Northwest A&F Univ, Coll Nat Resources & Environm, Yangling 712100, Shaanxi, Peoples R China; [Yang, Kai; Zhao, Yunge; Gao, Liqian; Sun, Hui; Gu, Kangmin] Northwest A&F Univ, Inst Soil & Water Conservat, State Key Lab Soil Eros & Dryland Farming Loess P, Yangling 712100, Shaanxi, Peoples R China; [Sun, Hui] Northwest A&F Univ, Coll Forestry, Yangling 712100, Shaanxi, Peoples R China
推荐引用方式 GB/T 7714	Yang, Kai,Zhao, Yunge,Gao, Liqian,et al. Nonlinear response of hydrodynamic and soil erosive behaviors to biocrust coverage in drylands[J]. 西北农林科技大学,2022,405.
APA	Yang, Kai,Zhao, Yunge,Gao, Liqian,Sun, Hui,&Gu, Kangmin.(2022).Nonlinear response of hydrodynamic and soil erosive behaviors to biocrust coverage in drylands.GEODERMA,405.
MLA	Yang, Kai,et al."Nonlinear response of hydrodynamic and soil erosive behaviors to biocrust coverage in drylands".GEODERMA 405(2022).