Meta-analysis indicates better climate adaptation and mitigation performance of hybrid engineering-natural coastal defence measures.

Traditional approaches to coastal defence often struggle to reduce the risks of accelerated climate change. Incorporating nature-based components into coastal defences may enhance adaptation to climate change with added benefits, but we need to compare their performance against conventional hard measures. We conduct a meta-analysis that compares the performances of hard, hybrid, soft and natural measures for coastal defence across different functions of risk reduction, climate change mitigation, and cost-effectiveness. Hybrid and soft measures offer higher risk reduction and climate change mitigation benefits than unvegetated natural systems, while performing on par with natural measures. Soft and hybrid measures are more cost-effective than hard measures, while hybrid measures provide the highest hazard reduction among all measures. All coastal defence measures have a positive economic return over a 20-year period. Mindful of risk context, our results provide strong an evidence-base for integrating and upscaling nature-based components into coastal defences in lower risk areas.

Linking the nonmaterial dimensions of human-nature relations and human well-being through cultural ecosystem services.

Nature contributes substantially to human well-being through its diverse material and nonmaterial contributions. However, despite the growing literature on the nonmaterial dimensions of human-nature relations, we lack a systematic understanding of how they are linked with human well-being. Here, we use the concept of cultural ecosystem services (CESs) as a lens to explore this interface. Through a systematic review of the peer-reviewed literature, we elicit the unique pathways and mechanisms linking individual CESs and constituents of human well-being, as well as their relative effects. Subsequently, we identify their complex interactions through latent class analysis and multiple correspondence analysis, which delineate five major assemblages that reflect synergies and trade-offs at the interface of CESs and human well-being. We critically discuss key research trends and gaps and propose directions for future research and practice to leverage the potential of the nonmaterial contributions of nature for human well-being and sustainability more broadly.