Praise for diversity: A functional approach to reduce risks in urban forests

Abstract

Urban forests are associated with important ecosystem services, such as reduced environmental exposure and improved human health. These benefits will become even more important with climate change, especially with most humans now living in cities. Yet urban trees are themselves threatened by the changing climate, unprecedented urban growth and new exotic pests and diseases. Hence, to maintain the services provided by urban forests, developing efficient tree management practices aimed at minimizing the risk of catastrophic tree mortality becomes ever more important.Traditional practices often promote low-diversity tree communities to meet the demands of a taxing urban environment and the preferences of citizens. However, these low-diversity communities are inherently more susceptible to collapse. Here we present an intuitively simple and user-friendly urban tree management approach that integrates the latest advances in functional ecology to minimize the risk of catastrophic urban tree mortality caused by future uncertain environmental conditions in order to maintain forest cover and preserve urban ecosystem services.