The millennia-old relationship between town and country is being transformed. Rapid urbanization is taking place all over the world, driven largely by rural migration, resulting in urban sprawl and slum developments as well as in the development of high quality infrastructure and overall improvement in the standard of living. The footprint of cities extends far beyond their boundaries but cities can offer economies of scale.
Chapter 11: Urbanization
Rapid urbanization is taking place all over the world, driven largely by rural migration, resulting in urban sprawl and slum developments as well as in the development of high quality infrastructure and overall improvement in the standard of living. If current projections are accurate, 66 per cent of the world’s population will be living in cities by 2050. This is having dramatic impacts on the environment and increasing pressure on limited land resources; future urban expansion is likely to result in the loss of some of our more productive croplands. The footprint of the city – the impact that the city has beyond its boundaries – has many components, of which six are discussed:
- Food impacts, both directly from land use change and increased pressure to produce food for city dwellers
- Water use, with people living in urban areas tending to use proportionately more water than rural dwellers
- Transport infrastructure, both from a resource perspective and habitat fragmentation
- Urban soil sealing and impacts on the overall water cycle and susceptibility to extreme weather events
- Biodiversity loss
- Climate change impacts
Building sustainable cities
Distinguishing between urban and rural planning no longer makes sense given the extent to which the two are interconnected; sustainable approaches to managing cities must take into account urban areas as well as rural lands, communities, and the ecosystems that they depend on (Seitzinger et al., 2012). The steps needed to achieve sustainable cities, presented in this chapter, are:
- Minimizing the impact on land, such as soil sealing, land use change, etc.
- Reducing the urban food and energy footprint
- Integrating water management at the catchment scale to ensure sustainable supplies
- Developing sustainable transport systems
- Maximizing climate mitigation and adaptation in an urban context
- Cutting pollution of water and air
- Reducing resource use through effective recycling
- Designing green spaces and protecting biodiversity inside and outside the city.