Bastiaan Notebaert

In the NBRACER Horizon Europe project, 14 nature-based solutions (NbS) are demonstrated for climate adaptation in rural lanscpaes in the Atlantic region. These solutions are spread over four demo regions Western-Denmark, West-Flanders (Belgium), Nouvelle Aquitaine (France) and Cantabria (Spain). These demonstrators address a range of climate challenges, such as flooding, drought, water quality degradation, and soil erosion, while targeting improvements in Key Community Systems (KCSs) like Water Management, Ecosystems, and Land use & Food Systems. Each of the demonstrators includes a co-design process and monitoring of demo impacts. The methodology combines participatory stakeholder engagement with technical assessments, including ecosystem service mapping and readiness level evaluations. Innovation in the demonstrators focusses on different aspects, depending on the local barriers and enablers, such as technological readiness but also co-design and social acceptance, governance aspects and innovation in funding.In this presentation we provide an overview of the demonstrators and their co-design processes. The co-design process is guided by five iterative steps: issue framing, knowledge gathering, co-design of options, stakeholder validation, and decision-making. We present a comparative analysis of the demonstrators, highlighting the diversity of approaches, stakeholder constellations, and maturity levels. We also identify enabling conditions and barriers to implementation, such as governance structures, data availability, and social acceptance.Key findings show that while most demonstrators are still in early co-design stages, there is strong alignment between local needs, stakeholder engagement, and the potential of NbS to deliver climate resilience. The insights from this deliverable will inform the development of regional NbS portfolios and adaptation pathways for the rural landscapes in NBRACER.

Nature-based solutions (NbS) are key to climate adaptation policy, yet upscaling across diverse landscapes remains challenging. Within the HEU-NBRACER project, we developed a process framework to up- and outscale NbS. This framework is applied to the Province of West-Flanders, Belgium, where climate adaptation strategies have been co-designed by integrating evidence-based science with participatory governance.First, we assessed risk at detailed spatial scales by combining available current and future spatial multi-hazard mapping with local vulnerability and exposure indicators. These risk maps informed stakeholder dialogues to prioritize risks and co-define a shared vision for climate resilience.At the same time, concrete NbS-actions were co-designed and demonstrated with municipal actors and stakeholders. This process captured perceived co-benefits, barriers, and enablers, ensuring context-specific feasibility and alignment with policy and planning.Next, solutions were identified and organized into a portfolio of process-based strategies (e.g., sponge landscape for water storage and retention; evapotranspiration-driven cooling for urban heat mitigation). Using a hotspot mapping approach, we identify where specific NbS are most effective by jointly considering biophysical effectivity (e.g., infiltration potential, connectivity) and risk reduction needs (e.g., locations with high flood or drought risk and vulnerable population):NbS hotspot score=hazard score ×vulnerability score ×effectivity scoreThe hotspot approach applied in this framework aligns with the methodology used by the Flemish climate portal (Klimaatportaal), ensuring consistency with governmental tools and facilitating integration into policy processes.For each strategy, we provide an overall score for climate benefits (drought and flood mitigation, soil erosion control, water quality improvements) and ecosystem services (food production, carbon sequestration and biodiversity enhancement) using multi-criteria scoring informed by expert interviews and literature study. During a co-design process informed by the NbS hotspot scores, local stakeholders finally identified actionable pathways to also implement those NbS. This is done for a specific subregion in West-Flanders, as part of the Landscape Park Zwinstreek.Results deliver a portfolios of strategies, NbS hotspot maps, and actionable pathways to support decision-making and implementation. The framework bridges science, practice, and policy, enabling transparent prioritization, stakeholder ownership, and scalable NbS deployment for climate adaptation.

This research has two objectives: (I) to improve the methodology of using small-sized iron slag (microslag) as a stratigraphic marker to reconstruct the centennial-scale floodplain evolution and (II) to study the geomorphic evolution of the Ardennian rivers using the evaluation of the concentration of microslag in alluvia. In addition, 14C dating, topographic surveys and sedimentological analysis were carried out. Using these data, floodplain processes have been quantified in several Belgian rivers (Ardennes massif): fine floodplain sedimentation, lateral mobility rates and channel incision phases. A major hillslope erosion episode occurred during the Bronze Age. Archaeological data and historical sources indicate Roman and High Middle Age occupations in the area but no evidence of erosion or increased floodplain sedimentation have been observed. Several peat layers have been dated in the Chavanne floodplain to approximately 1000 BP and probably indicate very low anthropogenic activity and a high level of groundwater. Before 1000 CE, the fluvial style of the Ardennian rivers was probably different, characterized by a low-level forested floodplain, which explains the presence of frequent peat layers within the alluvial sequences and abandoned channels. From the eleventh century onwards, a generalized increase in sedimentation rates occurred, coinciding with a higher concentration of charcoal in the alluvium and also the formation of colluvial deposits. Analyses of slag concentrations allowed us to reconstruct the evolution of the floodplain topography. In Ardennian rivers, the mean floodplain aggradation over the last several centuries is between 3 and 20 cm/century, depending on the study site. Such differences in floodplain sedimentation rates can be explained by several factors such as the distance to past cultivation areas, the degree of woodland clearance, flow velocities during floods and the incision of the riverbed during last centuries, which reduces the frequency of inundation and, therefore, sedimentation on floodplains.

Glacial−interglacial variations in CO ₂ and methane in polar ice cores have been attributed, in part, to changes in global wetland extent, but the wetland distribution before the Last Glacial Maximum (LGM, 21 ka to 18 ka) remains virtually unknown. We present a study of global peatland extent and carbon (C) stocks through the last glacial cycle (130 ka to present) using a newly compiled database of 1,063 detailed stratigraphic records of peat deposits buried by mineral sediments, as well as a global peatland model. Quantitative agreement between modeling and observations shows extensive peat accumulation before the LGM in northern latitudes (>40°N), particularly during warmer periods including the last interglacial (130 ka to 116 ka, MIS 5e) and the interstadial (57 ka to 29 ka, MIS 3). During cooling periods of glacial advance and permafrost formation, the burial of northern peatlands by glaciers and mineral sediments decreased active peatland extent, thickness, and modeled C stocks by 70 to 90% from warmer times. Tropical peatland extent and C stocks show little temporal variation throughout the study period. While the increased burial of northern peats was correlated with cooling periods, the burial of tropical peat was predominately driven by changes in sea level and regional hydrology. Peat burial by mineral sediments represents a mechanism for long-term terrestrial C storage in the Earth system. These results show that northern peatlands accumulate significant C stocks during warmer times, indicating their potential for C sequestration during the warming Anthropocene.