Potential of high-rise greenery

In the past decade, we have seen the rise of high-rise greenery in Singapore. A new target of achieving 200ha of high-rise greenery by 2030 was set in 2014 after the previous target of 50ha by 2030 was met two decades earlier. As of 2014, Singapore has 61ha of greenery covering the exterior of the buildings; one of the highest among cities in the world. This huge increase could be due to the Skyrise Greenery Incentive Scheme (SGIS). Under the SGIS, NParks will fund up to 50% of the installation costs of rooftop greenery and vertical greenery.

Green roofs and vertical greening improves the thermal performance of the building, saving energy needed for air-conditioning. This is especially significant in Singapore given our climate. In addition, green roofs help with storm water discharge control, reduce noise pollution, improving air quality and reducing the urban heat island! With more buildings having vertical greenery coming up, I wonder about the potential for fauna among such urban greenery and its potential to be used as biodiversity corridors or stepping stones that allow connectivity between different urban parks and nature areas in Singapore. Would developers/building tenants choose to not attract biodiversity (or actively getting rid of them) as it would add to the maintenance cost of the green roof/wall making it sub optimal to plant? After all, I think the vertical greenery is mainly planted due to its attractiveness and for its properties of cooling the building.

Do contribute your thoughts and any possible ideas for improving connectivity through green roofs/walls!