Vertical greening systems - A review on recent technologies and research advancement

Vertical greening systems represent an emerging field in technology and research since they are traded as promising measure to encounter the negative impacts of climate change. Research and development in the field of green infrastructure are steadily progressing, determining aesthetic improvements as well as environmental, social and economic benefits.The purpose of this paper is to provide a systematic state-of-the-art in the field of vertical greening systems and identify significant gaps in research. Additionally, recent scientific studies are analysed to bundle existing knowledge on research in the specific field of green walls and to derive indications on set up practices to facilities and improvement of their post-comparability. The study is based on literature review using scientific literature such as peer-reviewed journals, conference papers and books as well as master and doctoral theses, research reports, research articles and recommendations.The study concludes that benefits of vertical greening systems in current literature often refer to general benefits of vegetation. Specific knowledge has been promoted on microclimatic effects, but complementary studies with focus on vertical greening systems are still lacking. Additionally, it was revealed that there is great potential for research on vertical greening systems in rural areas, especially taking into consideration the application of green walls on construction buildings like shotcrete walls, tunnel portals or highway bridges. For better comparability of future studies, single parameter-centered analyses under constant and comparable conditions are recommended.