As we celebrate the International Day for Biological Diversity on 22nd May, we need to remember that cities can and must be part of solutions to protect biodiversity. Indeed, the COVID- 19 pandemic has reminded us that we need more green and resilient cities that support urban dwellers’ mental and physical health.
The world population is expected to grow to around 8.5 billion by 2030 and 9.7 billion by 2050, with the proportion residing in urban areas increasing from 55 per cent in 2018 to 68 per cent by 2050. Growing urban populations and the associated need for infrastructure will place increasing demands and pressures on resources.
The status of biodiversity, and the prospects for achieving the 2030 Agenda for Sustainable Development more generally, will depend on how the resource demands of this growing population are managed. And sustainable management of urban areas can help to reduce the impacts of growing population on biodiversity while also helping to contribute to other societal challenges, including human health.
‘Nature-based solutions’ for climate change mitigation and adaptation are especially valuable in cities where they can address multiple urban challenges simultaneously, including flooding, heat stress, drought and pollution of air and water, as well as reconnecting people with nature. All of these urban challenges also pose risks to health. For example, flooding increases water-borne diseases, heat stress increases the risk of high blood pressure and air pollution is associated with higher risk of strokes, childhood asthma and adverse birth outcomes.
Maintaining and encouraging food production within urban and peri-urban areas can improve the resilience of urban populations and reduce pressure on biodiversity by saving cropland conversion. This benefits biodiversity, by reducing the pressure for further conversion of distant ecosystems to cropland to feed growing urban populations. This rich biodiversity, in turn, benefits our gut health and strengthens our immune systems.
The rapid development of infrastructure beyond cities, especially from road building and urban sprawl, represents a substantial impediment to meeting biodiversity goals in the coming decades. Widespread application of additional measures to minimise the impacts of infrastructure development on biodiversity will therefore be necessary to achieve the 2050 Vision for Biodiversity.
There are several key things we need to do.
First, we need to promote local-level urban governance and transdisciplinary planning, accounting for biodiversity, among other societal needs, when decisions are made on urban development.
We also need to make greater use of green infrastructure, such as the preservation and creation of green spaces and wetlands, to support multiple needs of urban populations as well as to promote urban biodiversity.
It is also important to take account of the footprint of cities on ecosystems in distant locations through encouraging healthier diets, more sustainable use of materials in construction and minimising energy use with a shift towards sustainable energy sources.
Finally, we need to reflect biodiversity considerations in the planning and development of infrastructure investments, such as the design and management of transportation systems, and other linear infrastructure.
Let us all work together to achieve these goals and ensure that cities are part of the solution #ForNature.
Elizabeth Mrema is a Tanzanian biodiversity leader and lawyer, currently based out of Montreal, Canada. She is Assistant Secretary-General and Executive Secretary of the United Nations Convention on Biological Diversity.
Read more about work by Elizabeth and other #UrbanBetter Disruptors.