The world is experiencing an environmental crisis coupled with rapid urbanisation. This affects city ecosystems, which are a combination of the built environment, planned green spaces and natural biodiversity. They include streets, roofs, parks, trees, rivers and other urban features.
Ecosystems provide services like regulating air, water and soil quality. In cities, their role in regulating the climate is particularly important. Cities are generally warmer than surrounding rural areas. Greenery and vegetation mitigate this by providing shade and filtering air. They also absorb greenhouse gases and other pollutants.
