Unasylva 250 Forests and sustainable cities

More than half the world’s population now lives in towns and cities, and that proportion will continue to grow in coming decades. If planned and managed well, cities can be great places to live, but many urban developments cause environmental havoc – ultimately leading to problems such as urban “heat islands”, flooding, and air pollution. The cost for citizens is borne in deteriorating well-being; the costs for the planet include increased greenhouse gas emissions and other waste and the degradation of soils and waterways

Cities need forests. The network of woodlands, groups of trees and individual trees in a city and on its fringes performs a huge range of functions – such as regulating climate; storing carbon; removing air pollutants; reducing the risk of flooding; assisting in food, energy and water security; and improving the physical and mental health of citizens. Forests enhance the look of cities and play important roles in social cohesion; they may even reduce crime. This, the 250th edition of Unasylva, takes a close look at urban and peri-urban forestry (UPF) – its benefits, pitfalls, governance and challenges.

The world will continue to urbanize for decades to come. Villages will become towns, towns will become cities, and cities will become megacities. Ensuring that these urban expanses are both liveable and sustainable is a massive challenge to which UPF advocates and practitioners must rise. Safeguarding and sustainably managing forests and other green spaces in cities will be crucial for the health and well-being of the planet and its inhabitants.