Carbon sequestration through vegetative infrastructure (BVIs): A climate-smart approach towards sustainable environment

Abstract

Although cities significantly contribute to global carbon emissions, they also have significant potential to function as carbon sinks through building-integrated vegetative infrastructures (BVIs), such as green roofs, green walls and vertical terraces. These represent climate-smart engineering solutions that can enhance carbon sequestration (CS), though research on their effectiveness remains limited. The study aimed to (1) evaluate the CS potential of various BVI types, including green roofs, green walls and vertical terrace and (2) understand stakeholder perceptions and the factors influencing BVIs. Three buildings integrated with BVIs and located in urban environments were purposively selected for field data collection, including plant height, canopy area, base height and diameter, that were required for quantifying CS. Calculations were conducted individually for different selected types of structures per area and per time. The i-Tree Eco tool was used to quantify CS, carbon storage, and pollution removal. Semi-structured interviews were conducted with 40 professionals, including architects, civil engineers, quantity surveyors and sustainability officers those most responsible building construction to assess their awareness, experience and perceptions regarding BVI implementation using five-point Likert scale. Results indicated that vertical terraces exhibited the highest CS rates (1.326–3.81 kg/m²/year), followed by green walls (0.749–4.62 kg/m²/year) and green roofs (1.889 kg/m²/year). While awareness of BVI for CS was relatively high, practical experience remained limited (Wilcoxon signed-rank test, Friedman test). The hotels and office sectors emerged as the most suitable for BVI adoption, whereas the educational and manufacturing sectors faced structural and financial constraints (Wilcoxon signed-rank test). Experts expressed the importance of long-term evaluation methods, such as benefit-cost ratio and net present value, to justify sustainable investments over short-term gains (frequency-analysis). This study highlights the urgent need for scale up nature-based solutions that strengthen urban sustainability and support climate-smart design and policy against climate change.