Soil-mycelia systems for slope stabilisation

在英国和全球，暴雨是浅层山体滑坡和斜坡坍塌的众所周知的触发因素。当水渗入部分饱和土体时，孔压增大，土体的抗剪强度降低。在全球范围内，每年由降雨引发的致命山体滑坡多达350起，造成数千人死亡。在英国，在暴雨期间，每月有多达80起山体滑坡和斜坡坍塌的记录。这些事件对运输网络造成重大破坏，对经济和社会产生一系列影响。实施紧急维修的直接成本是巨大的：2016/17年度铁路网的例行维护成本为1.54亿GB，紧急维修成本可能是维护工程成本的100倍。实施天然山坡补救措施的成本也很高，例如苏格兰交通部在2007-2019年期间在苏格兰A83公路沿线的其余部分花费了1330万英镑。英国气候预测预测，随着冬季降雨量的增加和降雨强度的显著增加，冬季将更加温暖、潮湿，夏季将更加炎热、干燥。我们不断变化的气候将进一步影响英国天然和工程斜坡的稳定性，推动对其管理和维护的新方法的需求。该奖学金计划专注于开发一系列低成本、低碳、最小干预的地面工程技术，模拟自然生态系统中真菌菌丝的生长。这个项目将研究丝状真菌，即以菌丝(管状结构)形式生长的真菌。真菌菌丝的集合体称为菌丝体。当菌丝在土壤中生长时，它会形成一种天然的土工织物，将土壤颗粒缠绕在其网状结构中。菌丝体还会分泌生化产物，这些产物可以改变土壤的润湿性，有助于将土壤颗粒粘合在一起。该奖学金的目的是开发五种真菌生物技术，通过不同的机制提高斜坡的稳定性，包括：(I)减少水分渗透；(Ii)提高土壤粘聚力和抗地表侵蚀能力；以及(Iii)提供抗拉加固。这些真菌生物技术将基于设计五种不同结构的土壤-菌丝体系统。这些土壤-菌丝体系统的水力机械性能将通过控制养分供应和定位来优化菌丝生长。这一奖学金将使人们能够系统地展示土壤-菌丝体系统在地面工程中从实验室规模到现场规模的性能。这一雄心勃勃和冒险的研究计划将得到斯特拉斯克莱德在这一生物地质工程这一新途径上创建的国际领先研究团队的支持。拟议中的真菌生物技术可能会改变地面工程方法，以加固斜坡。有了“种植”土壤改良的能力，就有机会处理更多的土壤；这些技术可以用于流域规模的滑坡缓解，提高工程基础设施的复原力，用于侵蚀控制和荒漠化。

Heavy rainfall is a well-known trigger of shallow landslides and slope failures in the UK and globally. As water infiltrates into partially saturated soil, pore water pressures increase and the shear strength of the soil reduces. Globally, up to 350 fatal landslides are triggered by rainfall each year causing thousands of deaths. In the UK up to 80 landslides and slope failures are recorded per month during periods of heavy rainfall. These events cause major disruption to transport networks with a range of economic and social impacts. The direct costs of implementing emergency repairs are substantial: the cost of routine maintenance of the rail network in 2016/17 was £154M and emergency repairs can cost 100 times the cost of maintenance works. The cost of implementing remedial measures for natural hillslopes is also substantial, e.g. Transport Scotland spent £13.3M at the Rest & Be Thankful site along the A83 in Scotland between 2007-2019. UK climate projections predict warmer, wetter winters and hotter, drier summers with increasing winter rainfall and significant increases in rainfall intensity. Our changing climate will further impact on the stability of natural and engineered slopes in the UK, driving the need for novel approaches for their management and maintenance.This fellowship programme focuses on the development of a range of low-cost, low-carbon minimal intervention ground engineering technologies which mimick the growth of fungal mycelia that occurs in natural ecosystems. This project will investigate filamentous fungi, fungi that grow as hyphae (tube-like structures). The collective mass of hyphae of a fungus is known as the mycelium. As the mycelium grows through the soil, it forms a natural geotextile, entangling soil particles within its mesh. The mycelium also secretes biochemical products, which can alter the wettability of soils and contribute to 'gluing' soil particles together. The aim of this fellowship is to develop five fungal biotechnologies which can enhance slope stability via various mechanisms including: (i) reducing water infiltration (ii) enhancing soil cohesion and resistance to surface erosion and (iii) providing tensile reinforcement. These fungal biotechnologies will be based on engineering five types of soil-mycelia systems with differing architecture. The hydro-mechanical performance of these soil-mycelia systems will be optimised by controlling nutrient supply and positioning to orient mycelium growth. This fellowship will enable a systematic demonstration of the performance of soil-mycelia systems for ground engineering from lab-scale to field-scale.This ambitious and adventurous programme of research will be underpinned by the creation of an internationally-leading research team at Strathclyde in this novel avenue of biogeotechnical engineering. The proposed fungal biotechnologies could transform ground engineering approaches to slope stabilisation. With the ability to 'grow' soil modification comes the opportunity to treat far greater volumes of soil; these technologies could be deployed for landslide mitigation on a catchment-scale, for improved resilience of engineered infrastructure, for erosion control and desertification.