Nature-based solutions to climate change mitigation and adaptation in urban areas: perspectives on indicators, knowledge gaps, barriers, and opportunities for action

Nature-based solutions promoting green and blue urban areas have significant potential to decrease the vulnerability and enhance the resilience of cities in light of climatic change. They can thereby help to mitigate climate change-induced impacts and serve as proactive adaptation options for municipalities. We explore the various contexts in which nature-based solutions are relevant for climate mitigation and adaptation in urban areas, identify indicators for assessing the effectiveness of nature-based solutions and related knowledge gaps. In addition, we explore existing barriers and potential opportunities for increasing the scale and effectiveness of nature-based solution implementation. The results were derived from an inter- and transdisciplinary workshop with experts from research, municipalities, policy, and society. As an outcome of the workshop discussions and building on existing evidence, we highlight three main needs for future science and policy agendas when dealing with nature-based solutions: (i) produce stronger evidence on nature-based solutions for climate change adaptation and mitigation and raise awareness by increasing implementation; (ii) adapt for governance challenges in implementing nature-based solutions by using reflexive approaches, which implies bringing together new networks of society, nature-based solution ambassadors, and practitioners; (iii) consider socio-environmental justice and social cohesion when implementing nature-based solutions by using integrated governance approaches that take into account an integrative and transdisciplinary participation of diverse actors. Taking these needs into account, nature-based solutions can serve as climate mitigation and adaptation tools that produce additional cobenefits for societal well-being, thereby serving as strong investment options for sustainable urban planning.

Key insights for the future of urban ecosystem services research

Understanding the dynamics of urban ecosystem services is a necessary requirement for adequate planning, management, and governance of urban green infrastructure. Through the three-year Urban Biodiversity and Ecosystem Services (URBES) research project, we conducted case study and comparative research on urban biodiversity and ecosystem services across seven cities in Europe and the United States. Reviewing > 50 peer-reviewed publications from the project, we present and discuss seven key insights that reflect cumulative findings from the project as well as the state-of-the-art knowledge in urban ecosystem services research. The insights from our review indicate that cross-sectoral, multiscale, interdisciplinary research is beginning to provide a solid scientific foundation for applying the ecosystem services framework in urban areas and land management. Our review offers a foundation for seeking novel, nature-based solutions to emerging urban challenges such as wicked environmental change issues.

The economic crisis as a game changer? Exploring the role of social construction in sustainability transitions

Continuing economic turbulence has fuelled debates about social and political reform as much as it has stimulated actions and initiatives aimed at a more fundamental transition of dominant economic systems. This paper takes a transition perspective to explore, from a Western European viewpoint, how the economic crisis is actually viewed through a variety of interpretations and responded to through a range of practices. We argue that framing societal phenomena such as the economic crisis as "symptoms of transition" through alternative narratives and actions can give rise to the potential for (seemingly) short-term pressures to become game changers. Game changers are then defined as the combination of: specific events, the subsequent or parallel framing of events in systemic terms by engaged societal actors, and (eventually) the emergence of (diverse) alternative narratives and practices (in response to the systemic framing of events). Game changers, when understood in these terms, help to orient, legitimize, guide, and accelerate deep changes in society. We conclude that such dynamics in which game changers gain momentum might also come to play a critical role in transitions. Therefore, we argue for developing a better understanding of and methodologies to further study the coevolutionary dynamics associated with game changers, as well as exploring the implications for governance.