Reducing hydraulic erosion of surficial sand layer by inoculation of cyanobacteria

IF 1.3 Q3 ENGINEERING, GEOLOGICAL

Proceedings of the Institution of Civil Engineers-Ground Improvement Pub Date : 2022-02-18 DOI:10.1680/jgrim.21.00017

Asma Rabiei, Seyed Mohammad Ali Zomorodian, B. O’Kelly

{"title":"Reducing hydraulic erosion of surficial sand layer by inoculation of cyanobacteria","authors":"Asma Rabiei, Seyed Mohammad Ali Zomorodian, B. O’Kelly","doi":"10.1680/jgrim.21.00017","DOIUrl":null,"url":null,"abstract":"Biological approaches have captured the attention of researchers regarding the beneficial effects of cyanobacteria inoculation in improving surficial soil stability. However, a gap exists in the literature regarding the impact of inoculation by individual cyanobacteria on stability of sand under intense surface-water erosion. This study assesses the improvements achieved in erosion resistance for biological soil crust (BC) formed on medium–coarse silica sand. Specimen groups were inoculated with Nostoc sp. and Calothrix sp., incubated for 32- or 48 day periods and then tested using an erosion function apparatus (EFA), investigating a wide range of flow velocities (hydraulic shear stresses). The significance of BC attachment to (or detachment from) the specimen container sidewall was also investigated in the EFA testing. Compared with untreated sand, inoculated specimens had a significantly greater erosion resistance that increased with the incubation period, with Nostoc inoculum producing greater reductions in erodibility coefficients (45–75%) compared with Calothrix (16–67%). Contrasting bond structures introduced by Nostoc and Calothrix are highlighted by scanning electron microscopy images that showed long Nostoc filaments were entangled more strongly in sand pore voids compared with short Calothrix filaments. In conclusion, this study supports the idea of using cyanobacteria inoculation as an eco-friendly, cost-benefit and effective technique for mitigating land degradation.","PeriodicalId":51705,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Ground Improvement","volume":null,"pages":null},"PeriodicalIF":1.3000,"publicationDate":"2022-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"2","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Proceedings of the Institution of Civil Engineers-Ground Improvement","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1680/jgrim.21.00017","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ENGINEERING, GEOLOGICAL","Score":null,"Total":0}

引用次数: 2

Abstract

Biological approaches have captured the attention of researchers regarding the beneficial effects of cyanobacteria inoculation in improving surficial soil stability. However, a gap exists in the literature regarding the impact of inoculation by individual cyanobacteria on stability of sand under intense surface-water erosion. This study assesses the improvements achieved in erosion resistance for biological soil crust (BC) formed on medium–coarse silica sand. Specimen groups were inoculated with Nostoc sp. and Calothrix sp., incubated for 32- or 48 day periods and then tested using an erosion function apparatus (EFA), investigating a wide range of flow velocities (hydraulic shear stresses). The significance of BC attachment to (or detachment from) the specimen container sidewall was also investigated in the EFA testing. Compared with untreated sand, inoculated specimens had a significantly greater erosion resistance that increased with the incubation period, with Nostoc inoculum producing greater reductions in erodibility coefficients (45–75%) compared with Calothrix (16–67%). Contrasting bond structures introduced by Nostoc and Calothrix are highlighted by scanning electron microscopy images that showed long Nostoc filaments were entangled more strongly in sand pore voids compared with short Calothrix filaments. In conclusion, this study supports the idea of using cyanobacteria inoculation as an eco-friendly, cost-benefit and effective technique for mitigating land degradation.

查看原文本刊更多论文

接种蓝藻减少浅层砂层水力侵蚀

生物方法已经引起了研究人员对蓝藻接种在改善表层土壤稳定性方面的有益影响的注意。然而，关于单个蓝藻接种对强烈地表水侵蚀下沙子稳定性的影响，文献中存在空白。本研究评估了中粗硅砂对生物结皮(BC)抗侵蚀能力的改善。各组标本分别接种Nostoc sp.和Calothrix sp.，孵育32天或48天，然后使用侵蚀功能仪(EFA)进行测试，研究大范围的流速(水力剪切应力)。在EFA测试中，BC附着(或脱离)标本容器侧壁的重要性也进行了研究。与未处理的砂相比，接种后的砂具有更强的抗侵蚀能力，且随孵育时间的延长而增加，其中接种Nostoc后可蚀系数的降低幅度(45-75%)大于Calothrix(16-67%)。扫描电镜图像显示，Nostoc和Calothrix引入的键结构对比突出，Nostoc长丝比Calothrix短丝在砂孔空隙中纠缠更强。总之，本研究支持使用蓝细菌接种作为一种生态友好，成本效益和有效的技术来缓解土地退化的想法。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Proceedings of the Institution of Civil Engineers-Ground Improvement ENGINEERING, GEOLOGICAL-

CiteScore

3.10

自引率

8.30%

发文量

期刊介绍： Ground Improvement provides a fast-track vehicle for the dissemination of news in technological developments, feasibility studies and innovative engineering applications for all aspects of ground improvement, ground reinforcement and grouting. The journal publishes high-quality, practical papers relevant to engineers, specialist contractors and academics involved in the development, design, construction, monitoring and quality control aspects of ground improvement. It covers a wide range of civil and environmental engineering applications, including analytical advances, performance evaluations, pilot and model studies, instrumented case-histories and innovative applications of existing technology.