Urban Biodiversity Hotspots: Harnessing the Conservation Potential of Yards in Brazilian Tropical Cities

Residential yards are a common land use in tropical cities, and often poorly planned in terms of biodiversity conservation. One of the most striking features of tropical cities is deep social inequality: poor neighborhoods are often devoid of basic infrastructure, including parks. The social inequity is also reflected in the vegetation cover in residential landscapes: most upper and middle-income neighborhoods contain abundant and high-quality vegetation, meaning they have more shrubs, trees and greater species diversity compared to low-income neighborhoods, where cement reigns. Accelerated urbanization of the more than 5500 Brazilian cities may benefit from a conservation strategy that includes increasing support for biodiversity in urban ecosystems. In this chapter, drawing on a field study in two Brazilian urban areas, we report on the potential contribution of residential yards to both the conservation of tropical urban biodiversity and to improving food security for those in lower socio-economic groups. The introduction of vegetation into urban residential yards improves access to nature and its resulting social and environmental benefits. However, the area available for vegetation is threatened by increases in building footprint area in residential neighborhoods. Avoiding the so-called “tyranny of small decisions”, whereby the collective impact of individual householders’ yard management scales up to negatively affect biodiversity and ecosystem services, may require an integrated effort on the part of city governments, universities and other research institutions.