干旱区生态环境知识资源中心(Arid): Biologic improvement of a sandy soil using single and mixed cultures: A comparison study

Arid

DOI	10.1016/j.still.2018.10.010
	Biologic improvement of a sandy soil using single and mixed cultures: A comparison study
	Khaleghi, M.; Rowshanzamir, M. A.
通讯作者	Rowshanzamir, M. A.
来源期刊	SOIL & TILLAGE RESEARCH
ISSN	0167-1987
EISSN	1879-3444
出版年	2019
卷号	186 页码:112-119
英文摘要	Because of global environmental problems due to desert expansion and dust storms as well as constructional requirements, looking for more efficient and comprehensive methods to stabilize dune sands and weak grounds seems to be an essential necessity. MICP (Microbial-induced CaCO3 precipitation) is an innovative technique in which bacterial activities within soil mass are harnessed to modify the physical and mechanical properties of soils. This method produces calcium carbonate precipitation in the soil pores by fracturing urea in the presence of calcium ions. An important factor in achieving uniform calcite deposition (and hence consistent enhancement of geotechnical properties) throughout the treated soil mass is the protocol adopted for injecting the reagents of ureolytic bacteria, urea and calcium. In this research study, an urease microorganism (i.e. B. pasteurii) was prepared at single and mixed cultures (with B. subtilis) in the laboratory and injected into dune sand samples. After required and appropriate curing time, the samples were subjected under unconfined compression, direct shear and falling-head permeability tests. The test results showed significant strength improvement and reduction of permeability of the treated samples in comparison with those of the untreated soil, while the performance of the mixed culture was much better than that of the single culture in the stabilization outcome. More specifically, the unconfined strength of the soil samples treated with the mixed culture was 1.2 times that of samples treated with the single culture. The amount of permeability reduction in the mixed medium was also 34% more than that obtained with the single culture. The research results verified the capability of the application of biological treatment, particularly with the mixed culture, on the dune sand which may be regarded as a potential technique to control desert expansion, and dust storms through the stabilization of the weak grounds.
英文关键词	Calcite precipitation Mixed culture Sand Permeability Unconfined strength
类型	Article
语种	英语
国家	Iran
收录类别	SCI-E
WOS记录号	WOS:000452934500013
WOS关键词	CALCIUM-CARBONATE PRECIPITATION ; HYDRAULIC CONDUCTIVITY ; SHEAR-STRENGTH ; MICROORGANISMS ; CEMENTATION ; BACTERIA ; PEAT
WOS类目	Soil Science
WOS研究方向	Agriculture
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/218863
作者单位	Isfahan Univ Technol, Dept Civil Engn, Esfahan, Iran
推荐引用方式 GB/T 7714	Khaleghi, M.,Rowshanzamir, M. A.. Biologic improvement of a sandy soil using single and mixed cultures: A comparison study[J],2019,186:112-119.
APA	Khaleghi, M.,&Rowshanzamir, M. A..(2019).Biologic improvement of a sandy soil using single and mixed cultures: A comparison study.SOIL & TILLAGE RESEARCH,186,112-119.
MLA	Khaleghi, M.,et al."Biologic improvement of a sandy soil using single and mixed cultures: A comparison study".SOIL & TILLAGE RESEARCH 186(2019):112-119.