Living walls enhancing the urban realm: a review

Analysis of urban residential greening in tropical climates using quantitative methods

Urban green spaces play a crucial role in mitigating urban heat islands, providing shade, cooling, absorbing carbon dioxide, and releasing oxygen to enhance air quality. Understanding the user perceptions of residential greeneries is essential for effective planning and implementation of greening systems. This quantitative research explored user perceptions and preferences regarding residential greeneries through a structured questionnaire survey from 578 respondents. The responses from the densely populated Chennai city and the rest of Tamil Nadu, India, were analyzed. About 90% of residents are interested in having a garden, irrespective of location and residential characteristics. The most available space in Chennai's urban region is a balcony at 45%, followed by front and back gardens at 30% and vice versa for Chennai's suburban areas. The most preferred type is potted plants (30%) and climbers (20%) on balconies and near windows in Chennai. The most perceived challenges are installation and maintenance costs. The most influencing factors over the preference for greeneries and green walls are the house typology, house ownership, and site location. This study provides more insights to building designers and architects on planning and implementation of residential greeneries as per end users' preferences and perceptions.

Promoting stress and anxiety recovery in older adults: assessing the therapeutic influence of biophilic green walls and outdoor view

Previous research has already provided evidence regarding the favorable impact of green walls and outdoor views on stress reduction and anxiety alleviation. However, there has been limited exploration into the combined effects of green walls and outdoor views on older adults. In this study, a between-subjects experiment was conducted using virtual reality (VR) technology with 23 participants. Following exposure to stressors, each participant underwent four randomized sessions, each lasting 5 min, in various virtual reality (VR) environments, encompassing non-biophilic and biophilic environments (including green walls, outdoor views, and their combination). Throughout the process, we measured physiological indicators of stress responses, including heart rate, heart rate variability, skin conductance levels, and blood pressure, using biometric sensors. Psychological changes in participants, including anxiety levels, were evaluated through the State-Trait Anxiety Inventory, recovery scales, and self-reported emotional assessments. In conclusion, in comparison to non-biophilic environments, older adults consistently exhibited lower stress levels, experienced superior anxiety relief, and demonstrated improved recovery in nature connectedness environments, with a notably faster recovery rate. These findings suggest that the incorporation of nature connectedness principles into the indoor environments of public activity spaces within older adults care facilities can significantly contribute to stress reduction and anxiety alleviation among older adults. Furthermore, these effects appear to be contingent on the specific types of nature connectedness environments. These results can provide substantial evidence to support the design of indoor common activity spaces within older adults care facilities.

The Application of Nature-Based Solutions for Urban Heat Island Mitigation in Asia: Progress, Challenges, and Recommendations

PURPOSE OF REVIEW

Unprecedented urbanization in Asia affects the net radiation and energy flux of urban areas in the form of urban heat islands (UHI). The application of nature-based solutions (NbS) via urban green and blue infrastructures is a promising approach to mitigate UHI via urban boundary condition modifications, which affect the energy balance. This narrative review discusses the application of green and blue infrastructures in the Asian context by highlighting its progress, challenges, and recommendations. This review is descriptive in nature and includes perspectives on the discussed topics.

RECENT FINDINGS

Studies on the application of green and blue infrastructures in UHI mitigation are still scant in Asia. Their cooling performance is greatly influenced by their types, size, geometry, surface roughness, spread (threshold distance), temporal scales, topography, pollution levels, prevailing climate, and assessment techniques. Distinct urban characteristics, climatic conditions, environmental risks, lack of awareness and expertise, lack of policy and government incentives, and limited scientific studies are the major challenges in their implementation of UHI mitigation in Asia. Although green and blue infrastructures are associated with urban cooling, more in-depth experimental work and multidisciplinary research collaboration are paramount to exploring its implementation potential in Asia and other countries that share similar urban and environmental characteristics.