Comparative review of vertical greenery systems in China and Malaysia

The current research provides a comparative overview of Vertical Greenery Systems (VGS) investigations in China and Malaysia covering the time period of 2010 to 2024. The PRISMA framework was applied for the analysis of 61 empirical studies 45 from China and 16 from Malaysia. Both countries aim at sustainability but emphasize different aspects in their research, which is impacted by climate, socio-economic factors, and policy frameworks. Chinese research, which is backed by a government initiative, points at environmental impacts like thermal regulation, air quality, and carbon reduction. Malaysian research, though limited, emphasizes passive cooling, thermal comfort, and cost-effectiveness in a tropical climate. The Chinese research is mostly in the field of environmental sciences with 28.9% of the total while Malaysia has a more even representation of environmental, architectural, and interdisciplinary fields (each 18.8%). In terms of focus, Chinese studies dominate with environmental aspects (51.1%), whereas Malaysian studies share between economic (50.0%) and social benefits (31.2%). The results indicate that climate and governance are factors that determine VGS research direction and application. China has managed to integrate urban areas on a large scale, whereas Malaysia still struggles with policy and maintenance issues. The impact of this study is that it sets the stage for cross-country learning in order to promote the adoption of sustainable urban development.