Mangrove forests are vital for flood reduction, yet their failure mechanisms during storms are poorly known, hampering their integration into engineered coastal protection. In this paper, we aimed to unravel the relationship between the resistance of mangrove trees to overturning and root distribution and the properties of the soil, while avoiding damage to natural mangrove forests. We therefore (i) tested the stability of 3D-printed tree mimics that imitate typical shallow mangrove root systems, mimicking both damaged and intact root systems, in sediments representing the soil properties of contrasting mangrove sites, and subsequently (ii) tested if the existing stability models for terrestrial trees are applicable for mangrove tree species, which have unique shallow root systems to survive waterlogged soils. Root systems of different complexities were modeled after Avicennia alba, Avicennia germinans, and Rhizophora stylosa, and printed at a 1:100 scale using material densities matching those of natural tree roots, to ensure the geometric scaling of overturning moments. The mimic stability increased with the soil shear strength and root plate surface area. The optimal root configuration for mimic stability depended on the sediment properties: spreading root systems performed better in softer sediments, while concentrating root biomass near the trunk improved stability in stronger sediments. An adapted terrestrial tree resistance model reproduced our measurements well, suggesting that such models could be adapted to predict the stability of shallow-rooted mangroves living in waterlogged soils. Field tree-pulling experiments are needed to further confirm our conclusions with real-world data, examine complicating factors like root intertwining, and consider mangrove tree properties like aerial roots. Overall, this work establishes a foundation for incorporating mangrove storm damage into hybrid coastal protection systems.

City street trees are prominent features of urban green infrastructure and can be useful for climate change adaptation. However, street trees may face particularly challenging conditions in urban environments. Challenges include limited soil and space for growth surrounded by sealed surfaces, construction that damages roots, poor pruning and management, and direct vandalism. All of these challenges may reduce the capacity of street trees to provide social-environmental benefits, such as attractive landscapes, shading and cooling. Thus, street trees need specific care and resources in urban environments. In this perspective article, we call for a conversation on how to improve the conditions for city street trees. While research has broadly investigated street tree mortality and vulnerabilities, the social perspective may be missing, one that also involves the actions and care by human inhabitants. Here we share perspectives on current management options and discuss from a social-ecological perspective how these can be extended to involve urban residents.

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.

Introduction Nature-based solutions are increasingly recognized as vital components of urban resilience strategies, particularly within the framework of green infrastructure. This study aims to propose an approach that fosters symbiosis between green and gray infrastructure to address the challenges posed by climate change in urban environments.Methods We conducted a comprehensive review of guidelines and scientific literature to inform the selection of species and the design of root containers for urban tree planting. Additionally, we performed a multicriteria analysis and assessed water comfort to guide decision-making regarding species selection in specific city areas.Results The methodology was applied to a case study in Bogota, yielding insights applicable to any city with basic knowledge of suitable species for planting in built public spaces. Crucial criteria for selecting local species for sidewalks were identified, including size, permeability, soil compaction characteristics, and climatic adaptability. A list of desirable species adapted to all humidity zones of the case study city was generated. Hydrological sizing methods proposed are contingent upon both the species to be planted and the geometry of the streets.Discussion The approach and findings presented in this study promote the development of trees and their ecosystem services while mitigating potential damage to surrounding infrastructure.Conclusion Implementing strategies that facilitate symbiosis between green and gray infrastructure contributes to urban resilience and aids in climate change adaptation efforts.