Land degradation and soil erosion, intensified by frequent intense hydro-meteorological events, pose significant threats to ecological processes. In response to the environmental challenges, there is a growing emphasis on employing Nature-Based Solutions (NBS), such as Soil and Water Bioengineering (SWBE) techniques, which promote a sustainable approach and materials for the restoration of natural areas damaged by climate events, unlike traditional “grey” engineering works. However, the effective implementation of SWBE interventions requires a multidisciplinary monitoring approach, considering engineering, geological, ecological, biological, and landscape aspects. The success of these interventions depends on evaluating both short-term stabilities provided by the non-living supporting structure and the long-term development of vegetation introduced during the work. Monitoring should regard structural integrity assessments, vegetation evolution studies, and analyses of root system efficiency (distribution, mechanical characteristics, etc.). This study wants to fill the research gap in SWBE management by proposing a comparison of two study techniques for a root system development evaluation, within a multi-approach methodology for the assessment of these interventions in terms of soil stability and natural evolution. The paper provides insights into geotechnical analysis within a shallow landslide, comparing two different methods for the evaluation of root system evolution. Direct methods (RAR) and indirect methods (ERT) were used for root development monitoring and then compared. Vegetation development was assessed by NDVI parameter by analysing Landsat satellite images. An overall analysis of the data obtained from monitoring the study area shows good plant development, thanks to the SWBE intervention, which in addition to the slope stability effect contributes to better water regulation and initiates a natural ecological succession. The findings contribute to advancing the understanding of the effectiveness of SWBE techniques, offering valuable information for future bioengineering projects and environmental conservation efforts, and promoting them as sustainable techniques for natural recovery.

The long-term biodiversity effects of ecological restoration projects are essential to understanding the dynamics of environmental processes induced by different applied techniques. Nature-based solutions (NBS) are defined as actions that use nature to protect, sustainably manage and restore natural or altered environments, providing benefits for both ecosystems and human well-being. Among NBS, Soil and Water Bioengineering (SWBE) techniques combine plants with timber and stone structures to restore riverbanks, combat soil erosion, and stabilise landslide areas, merging technical functionality with environmental restoration.This study, conducted within the NBFC research centre, employs a multidisciplinary approach to monitoring biodiversity complexity (plants, soil microorganisms and insects) in ecological restoration projects using SWBE techniques. The research aims to quantify the multi-taxonomic diversity in a shallow landslide restored with SWBE methods in the Apuan Alps, Tuscany (Italy), and analyse the effects of ecological succession on biodiversity complexity.The study area includes three shallow landslides triggered during an extreme weather event in 1996. During the 2024 vegetative season, field surveys were conducted in (1) a SWBE-restored landslide, (2) a naturally evolved landslide, and (3) a controlled landslide with minimal anthropic disturbance. All sites share comparable characteristics (e.g., slope, exposure, surrounding vegetation, and soil type).Results show that slope stability in the SWBE restored landslide enables better development of tree vegetation, with a more structured canopy compared to the other two sites. Herbaceous species biodiversity indices indicate significant differences among sites, with the restored landslide achieving the highest alpha diversity, as evidenced by alpha-diversity index values. For soil microorganisms and insects, data elaborations show us differences in community composition according to beta-diversity analyses (Bray-Curtis parameters).These findings underscore the importance of SWBE techniques in enhancing biodiversity and restoring ecological stability in degraded landscapes. An interdisciplinary approach is crucial to better understanding the long-term effects of nature-based solutions on slope stability and environmental restoration.

Land degradation and soil erosion due to increasingly frequent extreme hydro-meteorological events, has negative consequences on ecological processes, making the environment, particularly rural and mountain areas, more susceptible to biodiversity loss. Nowadays, the use of plants as a building material transfers the plant multifunctionality within engineering structures and meets the demand rising from society for more environmentally friendly approaches to structure design. EU strategies and regulations require the employment of Nature-Based Solutions, such as Soil and Water Bioengineering techniques (SWBE). Soil and Water Bioengineering techniques are applied worldwide, achieving great results for slope and streambank stabilization, water regulation, landslides restoration and for mitigation of environmental impacts. SWBE techniques manage natural hazard control using plants as living material in combination with inert natural material, achieving two main goals: on the one hand the technical function of stabilizing the soil on the other hand the mitigation of environmental damage, initiating natural ecological processes. The research aims to evaluate the technical and ecological recovery effectiveness of a SWBE intervention for the restoration of a shallow landslide, occurred during Versilia flood in 1996. The project aims to monitor the evolution of vegetation and evaluate the composition of soil microorganisms by comparing the area restored by the intervention and surrounding areas. Field samplings and analysis will be conducted on two landslide bodies that occurred with the same extreme rainfall event: first site a landslide restored with SWBE techniques and the second site a naturally evolving landslide. A multi-approach methodology will be developed to evaluate differences and correlation between the ecological processes (vegetation and soil microorganism) and the technical efficiency of the landslide restoration intervention.

Monitoring, restoring and enhancing biodiversity is one of the most relevant issues in the transition towards more sustainable environmental solutions, but also to counter the effects of anthropogenic impacts and climate change. The development of new green jobs, together with the promotion of nature-based interventions, has increasingly pushed research to study NBS interventions, particularly those for restoring degraded areas, evaluating their effectiveness on ecological processes and the ecosystems.The promotion of nature-based techniques (NBS) has seen a growing interest in the use of plants as building materials, as is done in Soil and Water Bioengineering (SWBE) techniques, that combine the technical function for natural hazard control and environmental function for ecological process restoration. With an interdisciplinary approach, a common feature of projects under the NBFC research centre, we seek to study the impact of the use of SWBE techniques on biodiversity and ecological processes from various perspectives.Four main intervention sites have been identified where degraded areas have been or are to be restored with SWBE techniques. The study areas are in the locality of Pomezzana (LU), Torrente Sova (AR), Montisoni (FI) and Camaldoli (AR), all of which have been followed by the UNIFI DAGRI research group and carried out in different years, respectively: 25 years, 8 years, 3 years and to be carried out. We aim to assess the variation in biodiversity by comparing the areas restored with SWBE techniques to those with natural evolution adjacent to them, analysing various ecological parameters: vegetation, soil microorganisms, macroinvertebrates, and genetics of plant species.During 2023, the first vegetation surveys (trees, shrub and herbaceous layer) were conducted, and pilot soil sampling was carried out to quantify the microorganisms present. Regarding the vegetation, Braun-Blanquet surveys were conducted for the herbaceous component, in transects of equal size both in the restored area and in the adjacent control areas; for the arboreal and shrub component, a standard-sized (depending on the site) sample area was made with a total plant stand (D>3 cm). For the soil samples, transects were drawn across the restored area following the level curve.Initial data processing, on botanical survey of the plant species and the result of biodiversity indicators (Evenness, Shannon, etc.) revealed a difference in specific composition, and therefore environmental and microclimatic conditions, between the control plots and the restored area. The construction of the SWBE works, in timber and stone, and the use of rooted plants together with the sowing, create favourable conditions for the initiation of an ecological succession, even if it is not always in an excellent state compared to the control plots with 'natural' evolution. In the following elaborations we will try to understand the effect on soil microorganisms, and their relation within the vegetation composition, as well as to evaluate possible favourable conditions for the entry of alien and invasive species into the restored areas. (1) Dipartimento di Scienze e Tecnologie Agrarie, Alimentari, Ambientali e Forestali (DAGRI), Università degli Studi di Firenze