干旱区生态环境知识资源中心(Arid): The role of grain size and inoculum amount on biocrust formation by Leptolyngbya ohadii

Arid

DOI	10.1016/j.catena.2019.104248
	The role of grain size and inoculum amount on biocrust formation by Leptolyngbya ohadii
	Mugnai, Gianmarco 1,2; Rossi, Federico 1; Chamizo, Sonia 1,3; Adessi, Alessandra 1; De Philippis, Roberto 1
通讯作者	Rossi, Federico
来源期刊	CATENA
ISSN	0341-8162
EISSN	1872-6887
出版年	2020
卷号	184
英文摘要	Cyanobacteria are widespread prokaryotic organisms that represent feasible biotechnological tools to set up valid approaches to counteract desertification. Their peculiar physiological traits, and their resilience to abiotic stresses, allow their application on abiotically constrained soils to trigger their stabilization. A successful cyanobacteria inoculation results in the formation of cyanobacterial biocrusts, complex microbial communities characterized by tangled filament meshes imbued in a matrix of self-secreted extracellular polysaccharides (EPS) that keep loose sediments and aggregates firmly in place. However, the capability to form stable cyanobacterial biocrusts is not common to all the species, and a mix of factors can hamper the process, notably inoculum amount, and substrate characteristics. The aim of this work was to assess the influence of inoculum quantity and substrate granulometry on the physical stability of cyanobacterial biocrusts induced by inoculating the strain Leptolyngbya ohadii in a microcosm experiment, under laboratory conditions. After applying three different initial inoculum amounts on two different sand granulometries (medium and coarse sand), we assayed aggregate stability, physical stability and surface hydrophobicity on the resulting biocrusts during a 30-day incubation. Also, the features and the role of the EPS synthesized by L. ohadii were studied following their isolation, characterization, and direct application on the sand. The two EPS fractions produced by the strain, one more soluble and easily released in the surrounding medium (released polysaccharides, RPS) and one solidly attached to the filaments (glycocalyx EPS, G-EPS), were separately tested. Cyanobacterial biocrusts visibly formed in all the microcosms after 15 days. However, we observed a strong effect of sand granulometry in affecting aggregate stability and tensile strength, both of which appeared weaker on coarse sand. A higher amount of initial inoculum was necessary to produce stable biocrusts on coarse sand compared to medium sand. Also, we observed how the inoculation of EPS alone did not sort most of the significant effects that we detected by inoculating the whole culture, pointing at the importance of the action of the cyanobacterial filaments in soil conglomeration. However, a significant increase in physical stability was achieved by inoculating G-EPS on medium sand, suggesting the involvement of this fraction in biocrusts structuration. This work analyzes for the first time the effects of the variable grain size and inoculum amount in the achievement of physically stable biocrusts by cyanobacteria inoculation. The results that we obtained are useful in improving and optimizing the process of biomass preparation and dispersion for future indoor and outdoor studies.
英文关键词	Biocrusts Inoculation Aggregate stability Tensile strength RPS G-EPS
类型	Article
语种	英语
国家	Italy ; Spain
收录类别	SCI-E
WOS记录号	WOS:000525323800011
WOS关键词	BIOLOGICAL SOIL CRUSTS ; CYANOBACTERIAL EXOPOLYSACCHARIDES ; EXOCELLULAR POLYSACCHARIDES ; PHOTOTROPHIC BIOFILMS ; AGGREGATE STABILITY ; WATER-REPELLENCY ; INOCULATION ; MOTILITY ; MATRIX ; CARBON
WOS类目	Geosciences, Multidisciplinary ; Soil Science ; Water Resources
WOS研究方向	Geology ; Agriculture ; Water Resources
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/314218
作者单位	1.Univ Florence, Dept Agr Food Environm & Forestry Sci & Technol D, Via Maragliano 77, I-50144 Florence, Italy; 2.Univ Milan, Dept Food Environm & Nutr Sci DeFENS, Via Luigi Mangiagalli 25, I-20133 Milan, Italy; 3.Univ Almeria, Agron Dept, La Canada San Urbano S-N, Almeria 04120, Spain
推荐引用方式 GB/T 7714	Mugnai, Gianmarco,Rossi, Federico,Chamizo, Sonia,et al. The role of grain size and inoculum amount on biocrust formation by Leptolyngbya ohadii[J],2020,184.
APA	Mugnai, Gianmarco,Rossi, Federico,Chamizo, Sonia,Adessi, Alessandra,&De Philippis, Roberto.(2020).The role of grain size and inoculum amount on biocrust formation by Leptolyngbya ohadii.CATENA,184.
MLA	Mugnai, Gianmarco,et al."The role of grain size and inoculum amount on biocrust formation by Leptolyngbya ohadii".CATENA 184(2020).