Biogeotechnics最新文献

Exploring the uniformity of MICP solidified fine particle silt with different sample preparation methods 探讨不同制样方法下MICP固化细粒粉土的均匀性

Biogeotechnics

Pub Date : 2026-03-01 Epub Date: 2025-01-21 DOI: 10.1016/j.bgtech.2025.100163

Bo Kang , Hao Wang , Fusheng Zha , Congmin Liu , Annan Zhou , Rulong Ban

Microbial induced calcium carbonate precipitation (MICP) technology is widely used for reinforcement in geotechnical engineering due to its low cost, simple process, strong applicability and lack of secondary pollution. However, the presence of clay particles in silt increases the compressibility and decreases the permeability of soil, complicating the even distribution of slurry into soil pores. Therefore, it is necessary to develop a treatment technology which is suitable for silty soil sites, achieving effective solidification using MICP. This study examines three treatment techniques, including grouting, immersing and mixing methods, to solidify silt material. The strength characteristics of the solidified soil were analyzed by using unconfined compression tests. Results show that the mixing method provides the highest strength, followed by the grouting method, with the immersion method yielding the lowest strength. The uniformity of the solidified samples was assessed by determining calcium carbonate content, X-ray diffraction tests, and mercury injection tests. The MICP samples made by using immersing and grouting methods exhibited inhomogeneity in both radial and longitudinal directions. For the immersing method, calcium carbonate content decreased, pore volume increased, and the degree of cementation worsened progressively from the outer layer to the inner layer. For grouting method, the same phenomenon occurs from the bottom (grouting point) to the top. In contrast, the MICP samples with mixing method showed good homogeneity in all spatial directions. This study provides guidance and optimization strategies for applying MICP technology in silty soil sites.

微生物诱导碳酸钙沉淀（MICP）技术因其成本低、工艺简单、适用性强、无二次污染等优点，在岩土工程加固中得到了广泛应用。然而，粉土中粘土颗粒的存在增加了土体的压缩性，降低了土体的渗透性，使浆液在土体孔隙中的均匀分布变得复杂。因此，有必要开发一种适用于粉质土场地的处理技术，利用MICP实现有效的固化。研究了灌浆法、浸没法和搅拌法三种处理淤泥质材料的方法。采用无侧限压缩试验对固化土的强度特性进行了分析。结果表明：搅拌法强度最高，注浆法次之，浸水法强度最低；通过测定碳酸钙含量、x射线衍射测试和压汞测试来评估固化样品的均匀性。浸没法和灌浆法制备的MICP试样在径向和纵向上均表现出不均匀性。浸泡法碳酸钙含量降低，孔隙体积增大，胶结程度由外层向内层逐渐恶化。对于注浆法，同样的现象从底部（注浆点）到顶部发生。混合法制备的MICP样品在各空间方向上均表现出良好的均匀性。该研究为MICP技术在粉质土场地的应用提供了指导和优化策略。

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引用次数: 0

Eco-geotechnics under climate change: A state-of-the-art review 气候变化下的生态岩土技术：最新进展综述

Biogeotechnics

Pub Date : 2026-03-01 Epub Date: 2024-12-20 DOI: 10.1016/j.bgtech.2024.100158

Charles Wang Wai Ng , Qi Zhang , Haowen Guo , Junjun Ni , Yuchen Wang , Anthony Kwan Leung , Chao Zhou

Global climate change has exacerbated extreme weather events, such as intense rainfall and heat waves, resulting in the deterioration of geotechnical earthen structures. To address the urgent need for sustainable development, eco-friendly solutions are being explored, with vegetation emerging as a vital natural engineer. Despite the potential of vegetation, traditional practices often limit its role to aesthetics, overlooking the engineering benefits of plant roots. This paper introduces the new interdisciplinary field of eco-geotechnics, which integrates soil mechanics, ecology, botany, and atmospheric sciences, etc. to enhance geotechnical infrastructure. By focusing on atmosphere–plant–soil interactions, this review highlights how plants contribute to the stability of earthen infrastructure through root reinforcement and hydrological benefits. This paper also reviews recent advancements in constitutive modelling of vegetated soils, particularly focusing on a novel eco-unsaturated soil model. It discusses experimental testing of vegetated soils and their wide applications. Critical research gaps are identified in terms of the effects of extreme weather on root systems, soil cracking dynamics, ecological restoration in contaminated areas, and the synergistic effects of vegetation with sustainable soil stabilisers. Additionally, the use of smart monitoring techniques based on a combination of remote sensing and machine learning is proposed to assess vegetation–soil interactions in real-time. By integrating ecological and geotechnical processes, a comprehensive framework is recommended for future research directions in eco-geotechnics, which will ultimately facilitate the development of resilient engineering solutions that can withstand the challenges posed by climate change. The insights gained will be invaluable for improving the sustainability of geotechnical practices and enhancing the resilience of infrastructures in a changing climate.

全球气候变化加剧了极端天气事件，如强降雨和热浪，导致土工结构恶化。为了解决可持续发展的迫切需要，人们正在探索生态友好的解决方案，植被成为重要的自然工程师。尽管植被具有潜力，但传统做法往往将其作用限制在美学上，忽视了植物根系的工程效益。本文介绍了融合土力学、生态学、植物学、大气科学等学科的生态岩土工程这一新的交叉学科，以加强岩土基础设施建设。通过关注大气-植物-土壤的相互作用，本文重点介绍了植物如何通过根系加固和水文效益来促进土基础设施的稳定性。本文还回顾了植被土本构模型的最新进展，重点介绍了一种新的生态非饱和土模型。论述了植被土壤的试验检测及其广泛应用。在极端天气对根系的影响、土壤开裂动力学、污染地区的生态恢复以及植被与可持续土壤稳定剂的协同效应等方面，确定了关键的研究空白。此外，还建议使用基于遥感和机器学习相结合的智能监测技术来实时评估植被-土壤相互作用。通过整合生态和岩土工程过程，为生态岩土工程的未来研究方向推荐了一个全面的框架，这将最终促进能够承受气候变化带来的挑战的弹性工程解决方案的发展。所获得的见解对于提高岩土工程实践的可持续性和增强基础设施在不断变化的气候中的复原力将是非常宝贵的。

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引用次数: 0

Microbially induced carbonate precipitation for soil improvement: Insights from a meter-scale radial grouting trial 微生物诱导碳酸盐沉淀改善土壤：来自米尺度径向灌浆试验的见解

Biogeotechnics

Pub Date : 2026-03-01 Epub Date: 2024-12-09 DOI: 10.1016/j.bgtech.2024.100157

Guijie Sang , Rebecca J. Lunn , James M. Minto , Grainne El Mountassir

Despite the growing interest in microbially induced carbonate precipitation (MICP) for geotechnical applications, reports on meter-scale MICP trials for soil improvement remain limited, and controlling and predicting cementation efficiency on a large-scale is even more scarce. This study presented a meter-scale improvement of a poorly-graded sand (initial dry density: 1581 kg/m³, porosity: 40 %) through MICP in a cylindrical cell (diameter: 1 m; thickness: 15 cm) using a radial flow injection strategy, which involves injecting fluids radially from a single well located at the center while maintaining a constant hydraulic head at the outer boundary. Nine cycles of a two-phase MICP treatment were applied: Phase 1- injection of 0.7 pore volumes (PVs) of bacterial solution and 1-L water pulse; Phase 2- injection of 1.4 PVs of 0.5 mol/L cementing solution in two stages (i) 0.7 PV injection two hours after the bacteria were injected, and (ii) a further 0.7 PV injection the following morning after an overnight static reaction period. We observed non-uniform CaCO₃ precipitations along the distance from the central well and over the depth, which was induced by the decreasing flux towards the outer boundary under the radial flow pattern, along with influences from layered soil packing and hydraulically induced flow channels. CaCO₃ precipitation with distance from the central well follows a symmetric Gaussian-type distribution, with sufficient cementation to retrieve full-length cores occurring near the midpoint between the central well and the outer boundary. The unconfined compressive strengths of the full-length cores were in the range of 1.2–6.8 MPa with CaCO₃ contents of 0.08–0.17. Our study suggests that cementation level under radial flow conditions is controllable on a large scale and highly dependent on the injection volume of both bacteria and rinsing water pulse. The study provides a solid baseline for predicting and controlling CaCO₃ distribution in large-scale MICP soil improvement using a two-phase radial injection approach.

尽管人们对微生物诱导碳酸盐沉淀（MICP）在岩土工程中的应用越来越感兴趣，但关于微米尺度MICP土壤改良试验的报道仍然有限，而大规模控制和预测胶结效率的报道更是稀缺。该研究采用径向流注入策略，通过MICP对一种差级配砂（初始干密度为1581 kg/m3，孔隙度为40 %）进行了米级改造（直径为1 m，厚度为15 cm），该策略包括从位于中心的单井径向注入流体，同时在外部边界保持恒定的水力水头)。采用两相MICP处理9个循环：第1期-注射0.7孔体积（pv）的细菌溶液和1 l水脉冲；第2阶段-分两阶段注射1.4 PV的0.5 mol/L固井溶液(i)在注射细菌后2小时注射0.7 PV, （ii）在静反应过夜后第二天早上再注射0.7 PV。我们观察到CaCO3在距离中心井的距离和深度上的不均匀降水，这是由于径向流模式下向外边界的通量减少，以及分层土壤堆积和水力诱导流道的影响。CaCO3随距离中心井的远近而沉淀遵循对称的高斯型分布，在中心井和外边界之间的中点附近有足够的胶结，可以回收全长岩心。全长岩心无侧限抗压强度范围为1.2 ~ 6.8 MPa， CaCO3含量为0.08 ~ 0.17。我们的研究表明，径向流动条件下的胶结水平在很大程度上是可控的，并且高度依赖于细菌的注入量和冲洗水脉冲。该研究为利用两相径向注入方法预测和控制大规模MICP土壤改良中CaCO3的分布提供了坚实的基础。

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引用次数: 0

Evaluating the effect of soil grading on the UCS of MICP-treated sandy soils 评价土壤分级对micp处理砂质土壤UCS的影响

Biogeotechnics

Pub Date : 2026-03-01 Epub Date: 2024-10-10 DOI: 10.1016/j.bgtech.2024.100144

Reena N. Hora , Md Mizanur Rahman , Md Rajibul Karim , Simon Beecham

Many past studies have investigated the Unconfined Compressive Strength (UCS) behaviour of MICP-treated sandy soils and developed empirical relationships to predict strength improvement. While the UCS of MICP-treated soils can be affected by many factors such as chemical concentration, temperature, and biochemistry, it has been found that particle size (

d_{10}

) is one of the important contributing factors, but most of the previously published studies have not considered it. This study applied MICP on three different variants of Adelaide Industrial (AI) clean sands with different grain size distributions to evaluate the effect on UCS and Calcium Carbonate (

CaC O_{3}

) precipitation. To better understand the influence of particle size, this study also collected literature data on UCS,

CaC O_{3}

content and soil grading properties. A numerical method was used to interpolate the distribution of the combined data (literature and experimental) in 3D space to establish a clear correlation between UCS,

CaC O_{3}

content (CC) and the soil grading properties. So, contour plots were generated between UCS, CC, and

d_{10}

and other soil grading properties. Where the 2D and 3D plots could not clearly present the influence of

d_{10}

on the variation of UCS and CC, contour plots presented the distribution rather clearly. The contour plots showed a visible trend in the variation of UCS and CC for

d_{10}

and Coefficient of Curvature (

C_{c}

), but not for Coefficient of Uniformity (

C_{u}

).

许多过去的研究调查了无侧限抗压强度（UCS）行为的micp处理砂土，并建立经验关系，以预测强度的提高。虽然micp处理土壤的UCS受化学浓度、温度和生物化学等多种因素的影响，但已经发现粒径（d10）是重要的影响因素之一，但大多数先前发表的研究都没有考虑到这一点。本研究将MICP应用于三种不同粒径分布的阿德莱德工业（AI）洁净砂，以评估其对UCS和碳酸钙（CaCO3）降水的影响。为了更好地了解粒径的影响，本研究还收集了关于UCS、CaCO3含量和土壤分级特性的文献数据。采用数值方法对文献和实验数据组合在三维空间中的分布进行插值，建立UCS、CaCO3含量（CC）与土壤级配特性之间的清晰相关性。因此，在UCS、CC和d10等土壤分级属性之间生成等高线图。2D和3D图不能清楚地反映d10对UCS和CC变化的影响，等高线图能较清楚地反映其分布。等高线图显示，d10和曲率系数（CC）的UCS和CC的变化趋势明显，而均匀度系数（Cu）的变化趋势不明显。

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引用次数: 0

Increased erosion in biochar-amended soil: importance of integrating erosion control blankets and vegetation 生物炭改良土壤侵蚀加剧：整合侵蚀控制毯和植被的重要性

Biogeotechnics

Pub Date : 2026-03-01 Epub Date: 2025-01-13 DOI: 10.1016/j.bgtech.2025.100161

Monir Hossain , Apiniti Jotisankasa , Surachet Aramrak , Viroon Kamchoom , Satoshi Nishimura , Supakij Nontananandh , Tananop Muanlhao , Surat Semmad

Although biochar is widely recognized for enhancing various soil properties, its impact on soil erosion resistance remains unclear and sometimes shows contradictory results. The main objective of this study is to quantify the effects of corn-cob biochar amendment, both with and without erosion control blankets (ECB), as well as the influence of biochar/compost incubation time on erosion resistance of a silty sand. The study also investigates the effects of biochar on Atterberg limits, shear strength, and thermal conductivity. As biochar content increases from 0 % to 20 %, the liquid limit (LL), plastic limit (PL), and shrinkage limit (SL) rise by 8 %–10 %, suggesting that biochar-amended soil (BAS) retains more water without losing strength. The addition of biochar has minimal impact on the shear strength of BAS at lower normal stresses (<45 kPa) but reduces its thermal conductivity by about 70 %. Submerged jet erosion tests show that biochar alone increases soil erosion in BAS. However, when combined with ECB and vegetation, erosion is significantly reduced (up to 39 %). Overall, this study underscores the importance of utilizing biochar in combination with ECB and such vegetation as ruzi grass to mitigate soil erosion in the silty sand.

虽然生物炭被广泛认为可以改善土壤的各种性质，但其对土壤抗侵蚀能力的影响尚不清楚，有时结果也相互矛盾。本研究的主要目的是量化玉米芯生物炭添加和不添加侵蚀控制毯（ECB）的效果，以及生物炭/堆肥孵育时间对粉砂抗侵蚀能力的影响。该研究还调查了生物炭对阿特伯格极限、剪切强度和导热性的影响。当生物炭含量从0 %增加到20 %时，液限（LL）、塑性限（PL）和收缩限（SL）分别提高了8 % ~ 10 %，表明生物炭改性土壤（BAS）在不损失强度的情况下保留了更多的水分。在较低的法向应力（45 kPa）下，生物炭的加入对BAS的抗剪强度影响最小，但其导热系数降低了约70% %。浸没射流侵蚀试验表明，单独使用生物炭增加了BAS的土壤侵蚀。然而，当与ECB和植被结合使用时，侵蚀显著减少（高达39% %）。综上所述，本研究强调了生物炭与ECB和如紫草等植被结合使用对缓解粉质沙地土壤侵蚀的重要性。

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引用次数: 0

Kitchen waste bone-driven enzyme-induced calcium phosphate precipitation under microgravity for space biocementation 微重力下厨房垃圾骨驱动酶诱导磷酸钙沉淀用于空间生物胶结

Biogeotechnics

Pub Date : 2026-03-01 Epub Date: 2024-12-08 DOI: 10.1016/j.bgtech.2024.100156

Zhen Yan , Kazunori Nakashima , Chikara Takano , Satoru Kawasaki

This study validates the feasibility of extracting calcium and phosphorus from kitchen waste bones for crude enzyme-induced calcium phosphate precipitation (EICPP) under both normal and microgravity conditions. The experimental results demonstrate no significant differences in the degree of reaction and characteristics of precipitation between these environments. By leveraging local resources, reducing material transport costs, and addressing waste management challenges, this research underscores the potential for extraterrestrial construction, thereby enhancing sustainability in space environments. These findings offer promising insights for the application of space biocementation, particularly during the expansion phase of human settlements.

本研究验证了在正常和微重力条件下从厨余骨中提取钙和磷用于粗酶诱导磷酸钙沉淀（EICPP）的可行性。实验结果表明，不同环境间的反应程度和降水特征无显著差异。通过利用当地资源、降低材料运输成本和解决废物管理挑战，本研究强调了地外建筑的潜力，从而提高了空间环境的可持续性。这些发现为空间生物胶结的应用提供了有希望的见解，特别是在人类住区的扩展阶段。

引用次数: 0

Review of bio-enzyme for soil improvement 生物酶在土壤改良中的研究进展

Biogeotechnics

Pub Date : 2026-03-01 Epub Date: 2024-10-09 DOI: 10.1016/j.bgtech.2024.100143

Yuhao Li , Xiangwei Fang , Chunni Shen , Wenchen Jiang , Sheng Huang , Guoliang Ma

Traditional soil stabilizers, such as cement and lime, typically entail substantial energy consumption and environmental pollution. In contrast, bio-enzyme has emerged as a promising alternative, aligning with the imperatives of sustainable development, cost-effectiveness, and environmental friendliness. Bio-enzymes are primarily one or more protein molecules that catalyzes chemical reactions in the soil to form a cementing bond that stabilizes the soil structure and reduces the soil’s affinity for water. Currently, a plethora of studies on bio-enzyme have been conducted by scholars worldwide, yet there remains a notable absence of the systematic organization and comprehensive review of these findings. This study offers a thorough examination of bio-enzyme technology, encompassing its biochemical properties, mechanisms, the engineering properties of stabilized soil, bio-enzymatic composites, and its engineering applications. And current trends and future prospects of bio-enzyme are also scrutinized. This forward-looking study indicates that bio-enzyme functions through mechanisms such as cation exchange, specific binding, and surfactants, among others to diminish the electric double layer thickness and hydrophilicity of soil, consequently enhancing engineering properties of soil. And the improvement performance can be influenced by various factors, including soil properties, enzyme dosage, specificity, and sample preparation, etc. It is also noted that the composites of bio-enzyme with conventional stabilizers tend to enhance improvement performance more efficiently. The engineering applications of bio-enzyme have demonstrated its superiority over traditional stabilizers in soil improvement. However, the performance of treated soils with available bio-enzyme remains limited, highlighting the necessity for extracting novel bio-enzyme form plants/animals and determining its mechanisms and engineering mechanical properties. It is also essential to develop more bio-enzymatic composites and conduct application in-situ to develop relevant standards and application guidelines.

传统的土壤稳定剂，如水泥和石灰，通常需要大量的能源消耗和环境污染。相比之下，生物酶已成为一种有前途的替代方案，符合可持续发展、成本效益和环境友好的要求。生物酶主要是一种或多种蛋白质分子，它们催化土壤中的化学反应，形成一种胶结键，稳定土壤结构，降低土壤对水的亲和力。目前，国内外学者对生物酶进行了大量的研究，但缺乏对这些研究结果进行系统的组织和全面的综述。本研究对生物酶技术进行了全面的研究，包括其生化特性、机理、稳定土壤的工程特性、生物酶复合材料及其工程应用。并对生物酶的发展趋势和前景进行了展望。这一前瞻性的研究表明，生物酶通过阳离子交换、特异性结合、表面活性剂等机制发挥作用，减少土壤的电双层厚度和亲水性，从而提高土壤的工程性能。改良效果受多种因素的影响，包括土壤性质、酶用量、特异性、样品制备等。同时指出，生物酶与常规稳定剂的复合可以更有效地提高改良性能。生物酶的工程应用证明了其在土壤改良方面的优越性。然而，可用的生物酶处理土壤的性能仍然有限，突出了从植物/动物中提取新型生物酶并确定其机制和工程力学特性的必要性。开发更多的生物酶复合材料并进行原位应用，制定相关标准和应用指南也是必不可少的。

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引用次数: 0

Role of MICP treatment area in mitigating liquefaction-induced settlements for shallow foundation mcp处理区在减轻浅地基液化沉降中的作用

Biogeotechnics

Pub Date : 2026-03-01 Epub Date: 2025-06-09 DOI: 10.1016/j.bgtech.2025.100187

Md Kausar Alam, Ramin Motamed

Microbially Induced Calcite Precipitation (MICP) is an effective ground improvement technique for mitigating liquefaction-induced ground deformations. However, limited research has explored its application for reducing shallow foundation settlement in liquefiable soils. Understanding the extent of the area requiring MICP treatment beneath a foundation is critical to minimizing settlement. This study aims to evaluate the impact of the improvement area of MICP-treated blocks on mitigating liquefaction-induced settlements of shallow foundations using a series of 1 g shake table model tests. The dimensions of the treated blocks were determined based on the Boussinesq load distribution chart and treated to achieve a shear wave velocity of 250 m/s. Scaled shake table tests were conducted, modeled after a large-scale shake table experiment. The testing setup included three soil layers with different relative densities, with a shallow foundation placed on the surface crust. MICP-treated blocks of varying sizes were placed beneath the foundation. The results demonstrated that when the MICP-treated block was configured as either L×B× 1.25B or 1.5L× 1.5B×B - where L and B are the length and width of the foundation - resulted in substantial improvements, with reductions of 80% in foundation settlement and 98 % in foundation tilting. Notably, the L×B× 1.25B configuration achieved performance similar to the 1.5L× 1.5B×B, while reducing the treated volume by 44%. Furthermore, the results emphasize the importance of optimizing the MICP-treated area to effectively mitigate liquefaction, providing valuable insights into the practical application of MICP for improving the performance of shallow foundations in liquefiable soils.

微生物诱导方解石降水（MICP）是一种有效的缓解液化引起的地面变形的地基改善技术。然而，对其在液化土中减少浅基础沉降的应用研究有限。了解地基下需要MICP处理的区域范围对于减少沉降至关重要。本研究旨在通过一系列1 g振动台模型试验，评估micp处理块体改善区域对减轻浅基础液化沉降的影响。处理块体尺寸根据Boussinesq荷载分布图确定，处理后横波速度达到250 m/s。模拟大型振动台试验，进行了尺度振动台试验。测试设置包括三个相对密度不同的土层，在表层地壳上放置浅基础。不同尺寸的micp处理块放置在基础下方。结果表明，当micp处理块体配置为L×B× 1.25B或1.5 lx 1.5B×B（其中L和B是基础的长度和宽度）时，效果显著改善，基础沉降减少80%，基础倾斜减少98% %。值得注意的是，L×B× 1.25B配置实现了与1.5 lx 1.5B×B相似的性能，同时将处理体积减少了44%。此外，研究结果强调了优化MICP处理区域以有效缓解液化的重要性，为MICP在可液化土壤中改善浅基础性能的实际应用提供了有价值的见解。

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引用次数: 0

Proposing a new sustainable approach for sand improvement using biologically-derived calcium phosphate cement 提出了一种新的可持续的方法来改善沙子使用生物衍生的磷酸钙水泥

Biogeotechnics

Pub Date : 2025-12-01 Epub Date: 2024-08-27 DOI: 10.1016/j.bgtech.2024.100135

Sivakumar Gowthaman , Yuta Kumamoto , Kazunori Nakashima , Chikara Takano , Satoru Kawasaki

Bio-mediated soil improvement methods keep on gaining the attention of geotechnical engineers and researchers globally due to their nature-based elegance and eco-friendliness. Most prevalent bio-mediated soil improvement methods include microbially induced carbonate precipitation (MICP) and enzyme-induced carbonate precipitation (EICP). During their processes, the bacteria/free urease hydrolyzes the urea into ammonium and carbonic acid, which is accompanied by a considerable increase of alkalinity (about pH 9.0). The major problem associated with the above techniques is the release of gaseous ammonia that is extremely detrimental. Therefore, this study aims to propose a new sustainable approach involving lactic acid bacteria to facilitate the calcium phosphate mineralization for the strengthening of sand matrix. The major objectives of this investigation are: (i) to evaluate the urease activity of the lactic acid bacteria under different temperatures, pH conditions and additions of metal ions, (ii) to assess the treated sand matrix, (iii) to perform cost analysis. The outcomes indicated that Limosilactobacillus sp. could effectively facilitate the urea hydrolysis, hence increasing the pH from acidic to neutral and providing a desirable environment for the calcium phosphate to mineralize within the voids of the sand. The addition of 0.01 % Ni²⁺ in culture media was found to enhance the urease activity by 38.8 % and compressive strength over 40 %. A combined formation of amorphous- and whisker-like precipitates could bridge a larger area at particle-particle contact points, thereby faciliating a strong force-network in sand matrix. The mineralized calcium phosphate compound was found to be brushite. The cost herein for producing 1 L treatment solution was estimated to be about 2.5-folds and 11.8-folds lower compared to that of MICP and EICP treatment solutions, respectively. Moreover, since the treatment pH could potentially be regulated between acidic-neural range, it would greatly control the release of gaseous ammonia. With several environmental and economical benefits, the study has disclosed a new sustainable direction for sand improvement via the use of lactic acid bacteria.

生物介导的土壤改良方法以其自然优雅和生态友好的特点，不断受到全球岩土工程师和研究人员的关注。最流行的生物介导土壤改良方法包括微生物诱导碳酸盐沉淀（MICP）和酶诱导碳酸盐沉淀（EICP）。在此过程中，细菌/游离脲酶将尿素水解成铵和碳酸，同时碱度显著升高（pH约为9.0）。与上述技术相关的主要问题是气态氨的释放，这是极其有害的。因此，本研究旨在提出一种利用乳酸菌促进磷酸钙矿化以强化砂基质的可持续途径。本研究的主要目的是：(i)评估乳酸菌在不同温度、pH条件和金属离子添加下的脲酶活性，（ii）评估处理后的砂基质，（iii）进行成本分析。结果表明，limmosilactobacillus sp.能够有效地促进尿素水解，从而将pH从酸性提高到中性，为磷酸钙在砂土空隙内矿化提供了理想的环境。在培养基中添加0.01%的Ni2+，脲酶活性提高38.8%，抗压强度提高40%以上。非晶相和晶须相的结合形成可以在颗粒-颗粒接触点上桥接更大的区域，从而促进砂基质中强力网络的形成。矿化磷酸钙化合物被发现是刷石。与MICP和EICP处理液相比，生产1 L处理液的成本估计分别降低了约2.5倍和11.8倍。此外，由于处理pH可以在酸性-神经范围内调节，因此可以大大控制气态氨的释放。该研究具有良好的环境效益和经济效益，为利用乳酸菌对砂土进行可持续改良开辟了新的方向。

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引用次数: 0

Diatom-driven activation of in-situ lunar resource utilization for space farming 以硅藻为驱动的月球原位资源利用激活技术

Biogeotechnics

Pub Date : 2025-12-01 Epub Date: 2025-01-16 DOI: 10.1016/j.bgtech.2025.100162

Dong Liu , Yuxin Zhang

In this study, we demonstrate that diatoms, through their bioweathering process, can enhance the properties of lunar soil, thereby facilitating the cultivation of crops. Detailedly, diatoms can deconstruct lunar soil minerals to polish the sharp edge of the minerals and release nutrients, and aggregate lunar soil particles for water retention. In addition, diatoms possess a high degree of resilience to space conditions, with the capacity to consume carbon dioxide and release oxygen. Furthermore, they have been observed to utilize human waste as a source of sustenance, thus rendering them a promising candidate for the in situ modification of lunar soil. This study offers valuable insights into the potential for diatoms to contribute to future space habitation and exploration.

在这项研究中，我们证明了硅藻通过其生物风化过程可以增强月球土壤的性质，从而促进作物的种植。具体来说，硅藻可以分解月球土壤矿物质，打磨矿物质的锋利边缘，释放养分，并聚集月球土壤颗粒，保持水分。此外，硅藻对空间条件具有高度的适应能力，具有消耗二氧化碳和释放氧气的能力。此外，人们还观察到它们利用人类的排泄物作为一种食物来源，因此它们很有希望成为原位改造月球土壤的候选者。这项研究为硅藻在未来太空居住和探索方面的潜力提供了有价值的见解。

引用次数: 0