Nature-Based Solutions最新文献

The traditional Japanese river training structure, known as “Seigyu”, designed to divert flow, reduce flow velocity, and promote geomorphological changes, is expected to contribute to the management of river morphology. Seigyu is highly impervious at the bottom giving it a unique function. Twelve Seigyus were installed in the Kizu River in Japan to assess their ability to serve as a sediment management structure, which is necessary when considering sediment replenishment from upstream dams constructed upstream. Images and videos were recorded by a UAV to assess the flow and morphology around Seigyu via image-based analysis. Additionally, the shift in its function caused by the transformation of Seigyu itself, such as tilting and clogging, was investigated. The detected geomorphological changes indicated that Seigyu contributed to the formation of complex morphological patterns and the continuous shift in the sediment budget from erosional to depositional. Even after tilting approximately 25°, Seigyus’ effects were sustained. High-velocity flow, which occurred between two Seigyus in the early stages after implementation, did not appear or at least decreased in velocity after debris was trapped between the Seigyus. These results suggest that the effects of Seigyu persist even after its transformation, and future simulations and implementations should consider these changes.

Invasive species profoundly impact ecosystems globally, not only threatening biodiversity by displacing native species but also disrupting ecological balances and imposing significant economic burdens. This has led countries to actively combat these pervasive threats. In China, Spartina alterniflora, an invasive species, has taken over more than 70 % of the coastal zone in just 50 years, especially in salt marsh. This study aims to assess the Spartina alterniflora eradication project in Dongtan of Chongming Island, Shanghai, based on the IUCN Global Standard for Nature-based Solutions (NBS). To ensure the comprehensiveness and diversity of the assessment process, stakeholders with diverse backgrounds were invited. The Dongtan project was qualitatively evaluated using the IUCN self-assessment tool for its adherence to the IUCN NBS Standard, identifying its strengths, weaknesses, improvement areas, and contributions to the national eradication campaign. The results show that the Dongtan Project closely aligns with the NBS standard, achieving an 88 % match, and demonstrates excellence in addressing societal challenges, enhancing biodiversity, and offering multiple benefits. Nevertheless, improvements can be made in Economic Feasibility (Criterion 4), Inclusive Governance (Criterion 5), and Balance Trade-offs (Criterion 6). The study underscores the importance of employing NBS standards for self-assessment in the project design phase, which facilitates the identification and refinement of potential design issues. The success of the Dongtan Project, exemplified by its effective Spartina alterniflora eradication strategies, serves as a compelling model for similar national campaigns.

Ecosystem restoration, as a core strategy for implementing Nature-based Solutions (NbS), inherently aligns with NbS principles. Despite significant progress in biodiversity conservation and restoration, China still faces risks of ecosystem degradation. To maximize the potential of NbS in China's restoration efforts, it is crucial to develop a framework rooted in NbS principles. However, the application of NbS is hindered by weak theoretical foundations and a lack of comprehensive case studies. This study integrated NbS principles with key theoretical concepts, including sustainable development, socio-ecological systems, ecosystem services, biodiversity, restoration ecology, natural capital, and ecological products, to develop a NbS-based theoretical framework for ecosystem restoration. Drawing on insights from the "Generation Restoration'' report, we synthesized representative practices across various Chinese ecosystems, including farmlands, forests, freshwater, grasslands, oceans, coasts, peatlands and urban areas. Our study provides both a theoretical foundation and practical guidance for integrating NbS into ecosystem restoration, aiming to enhance conservation efforts and promote sustainable development in China.

Climate change is exacerbating shoreline erosion and flooding, posing significant risks to coastal communities. Although traditional coastal defenses such as seawalls, dykes, and breakwaters offer protection from these hazards, their high environmental and economic costs are driving interest in cost-competitive nature-based solutions. Coral reef restoration is a nature-based solution that may be particularly apt to mitigate tropical coastal flooding and shoreline erosion while providing benefits to local tourism, fisheries, and nature. However, the novelty of this field requires studies demonstrating the benefits of reefs for coastal protection. While the flood protection benefits of reefs have been well-documented, their effects on shoreline erosion are comparatively less understood. Here, we investigate the effects of coral reefs on shoreline erosion by comparing tropical beach responses at short and long timescales, as well as identifying important reef structural features influencing coastal erosion rates. Our analyses leveraged two key datasets created in this study: the first derived from a literature review on short-term shoreline erosion due to storm events, and another compiling >80 years of long-term erosion rates, bathymetry, habitat, and wave energy for the Hawaiian Islands of Kauaʻi, Oʻahu, and Maui. Our analyses reveal three key findings regarding the effects of reefs on shoreline erosion. Firstly, we find evidence for the role of reefs in mitigating shoreline erosion during storm events, with coral reef-protected beaches experiencing 97 % less beach volume loss than unprotected beaches. Secondly, a linear regression analysis demonstrates that coral reef structure and wave energy are important predictors of long-term shoreline erosion rates, explaining 34 % of the variation across the Hawaiian Islands. Consistent with prior research, we find beaches protected by coral reefs with shallow reef crests, wide reef flats, calmer offshore conditions, and positioned farther from the shore exhibit lower erosion rates than others. Finally, when comparing historical erosion rates of protected and unprotected beaches in Hawai'i, we find a seemingly incongruous pattern where coral reef-protected beaches eroded up to 2x faster than beaches without reefs. While the cause of the enhanced erosion is yet to be fully understood, a combination of coral reef structural degradation and sea-level rise is likely shifting the equilibrium profiles of reef-protected beaches inshore. These results emphasize the role of coral reefs in reducing coastal erosion during storm events while revealing contrasting erosion patterns over long timescales. Future studies would ideally broaden the scope to include various regions, utilize advanced sediment transport models, and undertake field experiments to deepen our understanding of coral reef-coupled shoreline dynamics.

Arid and Semi-Arid Lands (ASALs) in Africa, covering 66 % of the continent and are home to around 200 million people, face significant water scarcity challenges due to harsh climatic conditions. This systematic review assesses the effectiveness, socio-economic impacts, and implementation challenges of Nature-based Solutions (NbS) for water resource management in these regions. Analysing 9906 research articles narrowed to 143 studies, the review identified critical NbS interventions, including water conservation, soil moisture and conservation, water harvesting, conservation agriculture, agroforestry, and afforestation. The studies focused on biophysical aspects (31 %), socio-economic issues (39 %), or both (30 %), with an emphasis on water quantity (96 %) over quality (3 %). These interventions' direct (43 %) and indirect (55 %) impacts were examined. Findings show that 52 % of the studies meet all effectiveness criteria: socio-economic benefits, sustainable resource use, resource enhancement and conservation, and infrastructure sustainability. Stakeholder engagement in co-designing NbS significantly enhances their effectiveness and the integration of indigenous knowledge. Geographic distribution highlights concentrated research in eastern, southern, and western Africa, particularly in Ethiopia, Kenya, and South Africa, with underrepresentation in northern and central regions. The review identifies gaps in water quality interventions and calls for more comprehensive approaches. The review highlights NbS' potential to improve water availability, ecosystem resilience, and socio-economic development in ASALs. However, challenges such as limited stakeholder involvement, inadequate integration of indigenous knowledge, and regional research disparities need addressing. The study recommends prioritising the participation of local communities and stakeholders from the planning stages to implementation to enhance the effectiveness and sustainability of future NbS projects.

Many coastal communities worldwide are facing challenges caused by increasing sea levels. However, urban development, population growth and industrialisation in low-lying delta regions persist. This includes the Netherlands and British Columbia, Canada. Both regions explore new and innovative flood risk and adaptation strategies by initiating nature-based solutions (NBS) pilot projects and integrating research and community initiatives. The aim of this paper is to learn from the experiences with these NBS pilots and support practitioners with insights and knowledge about the prospectives and implementation process of NBS. Our study takes a bird's eye view by diving into four NBS case study projects that try to enhance flood defence and quality of life while considering ecosystems and community values simultaneously. To better understand current initiatives on NBS, we first describe the historical trajectories of flood risk management and climate adaptation policy in both countries. Then we analyse two urban and two suburban case studies to identify and compare enablers and barriers that surround the implementation of NBS. We use the Pilot Paradox as a framework to reflect on the enablers and barriers, and to formulate recommendations for barriers that are common ground. We found that upscaling of the pilots forms an important challenge in both countries. We also found that Canada is interested in exchanging technical knowledge, experiences, and insights with other countries through the involvement of international researchers, consultants, and students in projects. Such collaboration between countries, communities, practitioners, and academics could accelerate the development of innovative climate adaptation strategies worldwide.

The concept of Nature-based Solutions (NbS) has gained interest as an approach to make significant contributions to the transformation towards more liveable, sustainable, and climate-resilient cities. However, the uptake of NbS into urban development practice is hindered by knowledge and governance barriers. Knowledge plays an essential role in evidence-based decision-making processes and in building the capacity to co-design sustainable pathways. In turn, governance processes can greatly support the acquisition, dissemination and application of knowledge. However, little is known about how these interactions between governance and knowledge manifest in practice. Therefore, we aim to understand the interplay between governance and monitoring & assessment (M&A) and the associated challenges and opportunities for NbS implementation in European and Latin American cities. Considering different socio-economic and cultural contexts allows us to draw from a wider range of practitioners’ experiences in different governance settings. We conducted an explorative qualitative content analysis on ten semi-structured expert interviews with thirteen city experts from local governments and academia based in seven cities: Bogota (CO), Buenos Aires (AR), Santiago (CL), São Paulo (BR), Barcelona (ES), Lisbon (PT) and Turin (IT). Our findings show that M&A provides agency for individual, institutional actors to steer political commitment and can support integrated working. The potential of collaborative M&A with non-governmental actors is still largely untapped, which requires acknowledgement of the capacities of non-governmental actors to contribute to M&A and raise awareness of the value of M&A to civil society. Furthermore, we recommend integrating more reflective learning opportunities in M&A processes, paying more attention to data sharing, and considering of more feasible M&A processes.

Ambition to leverage the power of nature-based solutions (NbS) to address global challenges such as the interlinked climate change and biodiversity crises has reached unprecedented levels. Despite a growing consensus around the potential benefits of NbS, this ambition has not translated into sufficient actionable progress in practice. Cities, increasingly recognized as centres of transformative capacity, have become a focal point for achieving NbS ambitions. Nevertheless, the transition from theoretical discourse to practical implementation has been slow, with NbS frequently being overlooked until recently in political agendas. A key obstacle to progress is the lack of action-oriented research grounding theoretical discussions in empirical evidence on NbS policy design and application. This paper seeks to address these knowledge gaps by: (i) defining criteria for good practices in urban NbS policy design and implementation; (ii) assessing policy instruments from the Urban Governance Atlas (UGA) against these criteria using mixed statistical and qualitative methods; and (iii) identifying potential pathways and actionable measures to promote the adoption of good practices in practice. Drawing on the diverse UGA examples, with a particular focus on Europe and the CELAC region, the paper identifies seven good practice criteria and outlines four potential pathways and related actions to guide the development of NbS policy instruments across varied urban contexts. Concrete recommendations around actionable knowledge aim to tap the transformative potential of NbS in addressing pressing global issues.