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Nature-based solutions (NbS) have emerged as a key strategy for sustainably addressing multiple urban challenges, with rapidly increasing knowledge production requiring synthesis to better understand whether and how NbS work in different social, ecological, economic, or governance contexts. Insights in this Perspective are drawn from a thematic review of 61 NbS review articles supported by an expert assessment of NbS knowledge in seven global regions to examine key challenges, fill gaps in Global South assessment, and provide insights for scaling up NbS for impact in cities. Eight NbS challenges emerged from our review of NbS reviews including conceptual, thematic, geographic, ecological, inclusivity, health, governance, and systems challenges. An additional expert assessment reviewing literature and cases in seven global regions further revealed the following: 1) Local context-based ecological knowledge is essential for NbS success; 2) Improved technical knowledge is required for planning and designing NbS; 3) NbS need to be included in all levels of planning and governance; 4) Putting justice and equity at the center of urban NbS approaches is critical, and 5) Inclusive and participatory governance processes will be key to long-term success of NbS. We synthesized findings from the NbS review results and regional expert assessments to offer four critical pathways for scaling up NbS: 1) foster new NbS research, technological innovation, and learning, 2) build a global NbS alliance for sharing knowledge, 3) ensure a systems approach to NbS planning and implementation, and 4) increase financing and political will for diverse NbS implementation.
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This content will become publicly available on December 1, 2025
A 20-year systematic review of wave dissipation by soft and hybrid nature-based solutions (NbS)
A systematic review of 20 years of studies was conducted to understand wave dissipation trends of hybrid and natural (soft) coastal features, collectively referred to as nature-based solutions (NbS). Of 13,451 studies identified and 470 studies reviewed; only 50 studies consistently reported the basic parameters required to compare wave height dissipation. These studies were used to create a basic understanding of wave dissipation across soft and hybrid features along different cross-shore widths. More specific implementation guidance for NbS is limited due to the lack of consistent monitoring practices and protocol within and between soft and hybrid features. This disparity is greatest between soft and hybrid NbS. To fully understand best practices for the wide variety of soft and hybrid NbS, more uniform monitoring data is needed to assess and more fully define wave dissipation performance. Based on the findings of this review, eight parameters to measure the wave dissipation effectiveness of NbS features are proposed. These findings will inform the development and application of evaluation protocols for future NbS projects.
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- Award ID(s):
- 2110262
- PAR ID:
- 10574085
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Ecological Engineering
- Volume:
- 209
- Issue:
- C
- ISSN:
- 0925-8574
- Page Range / eLocation ID:
- 107418
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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