Ashley Bang, from the University of Oxford, won the Journal of Ecology Best Poster Award at the 2024 European Congress of Conservation Biology. In this blog post, Ashley, discusses her thesis: Opportunities to balance urbanization, climate change, and nature conservation policy agendas via nature-based solutions: A case study of Hong Kong.
In light of the recently concluded Convention of Parties (COP) for both biodiversity (COP16) and climate change (COP29), the need to take joint action for climate and nature has stood out more than ever. In practice, this will look different for each country or city depending on local ecological and societal contexts. Both climate and biodiversity policy agendas will also need to be balanced with ambitions for urbanisation and socioeconomic development, which often compete with progress towards environmental goals.
Hong Kong offers a unique case study to explore these issues. It has more skyscrapers in the world than any other city, but at the same time protects an unusually large proportion of natural habitats for wildlife. My research explored how nature-based solutions could provide joint benefits for climate, nature, and human wellbeing amidst Hong Kong’s landscape of urban development.
Nature-based solutions
Nature-based solutions (NbS) are actions that protect, sustainably manage, or restore natural ecosystems in ways that benefit both people and nature. For Hong Kong, this could range from the restoration of coastal mangroves to the greening of downtown areas. But what are the tangible benefits that NbS could offer for Hong Kong, now and in the future?
To explore this, I mapped and modelled some of these benefits – carbon storage, natural habitat provision, and flood protection – under future scenarios of urbanisation by 2030. Results showed Hong Kong’s natural landscapes currently offer large contributions for carbon storage: an estimated 10.8Mt of carbon, equating to approximately equivalent to the emissions reductions required to meet 2030 targets.
Under future scenarios of intensive real estate development, these benefits are greatly reduced when natural habitats are sacrificed for urban expansion. It suggests that Hong Kong’s land developers should consider re-developing existing built-up areas or disused barren land, rather than converting intact natural habitats.
Trade-offs and priorities
Crucially, my models helped highlight priority areas for NbS: places where they would best reduce climate change risks for urban developments while maximizing benefits for nature. One such area is the Mai Po Wetland Reserve, a vital habitat for Asian migratory bird species and Hong Kong’s most effective carbon sink – but also one of the most vulnerable locations to urban flood damage. NbS that protect and restore Mai Po’s wetlands and mangroves would provide crucial protection for neighbouring urban developments, such as the ongoing Northern Metropolis development, while helping Hong Kong make meaningful strides towards its climate and biodiversity goals.
Another area to note was the Hong Kong International Airport, highlighted as highly vulnerable to flood inundation. Here, the implementation of NbS would be crucial for not just the conservation of local wildlife, such as the endangered and endemic Romer’s Tree Frog (Liuixalus romeri), but also the resilience of tourism, business, and trade sectors that rely upon international transit through the airport.
While trade-offs may ultimately be inevitable at the interface between nature, climate and society, my research demonstrates the positive role that NbS can play in harnessing joint benefits and win-win opportunities. As for what’s next, I’ll be taking these insights forward to engage with stakeholders in government, real estate development, and environmental conservation to try and bring these opportunities to life for Hong Kong!