Suchergebnisse

The history of urban food forests (UFFs) dates back to ancient times, when civilizations incorporated edible species into wild forests to create an ecosystem as natural as and self-sufficient as possible. Since the second half of the 20th century, the practices of integrating edible plants into ornamental landscapes have spread throughout the world. Currently, UFFs must face a number of challenges similar to those encountered by urban forests: land tenure, governance, technical capacities, and pollution and global change issues, and must be addressed in order to identify the most suitable combination of productive, environmental, and socio-economic functions of UFF. The events on a global scale that occurred in the first decades of the 21st century are forcing those who live and work in urban environments to react quickly to address the upcoming challenges.

The management of urban forests is a key element of resilience planning in cities across the globe. Urban forests provide ecosystem services as well as other nature-based solutions to 4.2 billion people living in cities. However, to continue to do so effectively, urban forests need to be able to thrive in an increasingly changing climate. Trees in cities are vulnerable to extreme heat and drought events, which are predicted to increase in frequency and severity under climate change. Knowledge of species' vulnerability to climate change, therefore, is crucial to ensure provision of desired ecosystem benefits, improve species selection, maintain tree growth and reduce tree mortality, dieback and stress in urban forests. Yet, systematic assessments of causes of tree dieback and mortality in urban environments are rare. We reviewed the state of knowledge of tree mortality in urban forests globally, finding very few frameworks that enable detection of climate change impacts on urban forests and no long-term studies assessing climate change as a direct driver of urban tree dieback and mortality. The effects of climate change on urban forests remain poorly understood and quantified, constraining the ability of governments to incorporate climate change resilience into urban forestry planning.