Eco-geotechnics under climate change: A state-of-the-art review

Abstract

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.

Keywords

Eco-geotechnics / Vegetation / Unsaturated soil / Climate change

CRediT authorship contribution statement

Charles Wang Wai Ng: Supervision, Project administration, Funding acquisition, Conceptualization. Qi Zhang: Writing - original draft, Investigation, Formal analysis. Haowen Guo: Writing - original draft, Validation, Investigation, Formal analysis. Junjun Ni: Writing - review & editing, Writing - original draft, Supervision, Project administration, Funding acquisition, Conceptualization. Yuchen Wang: Writing - original draft, Validation, Investigation, Data curation. Anthony Kwan Leung: Supervision, Project administration, Conceptualization. Chao Zhou: Supervision, Project administration, Conceptualization.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgements

The authors are thankful for the Collaborative Research Fund (Grant No. C5033-23GF) and the Areas of Excellence (AoE) Scheme Fund (Grant No. AoE/E-603/18) awarded by the Hong Kong Research Grants Council under the Government of Hong Kong SAR, China. The corresponding author also would like to thank the National Natural Science Foundation of China (Grant Nos. 52308342 and U2340227) and the Fundamental Research Funds for the Central Universities (Grant Nos. RF1028623071 and 2242024k30066).

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