Drought mitigating nature-based solutions: a critical state-of-the-art review at global and regional scales

Natural disasters are creating a major collapse in human existence. Among the many, drought is becoming more frequent and intense. Therefore, mitigation/adaptation measures have to be set to reduce the impact. This can be achieved via the application of Nature-based solutions (NBSs). This concept is now gaining more attention than ever but with fewer applications. The primary goal of this review paper is to analyze the different NBSs targeted for drought impact mitigation. The study constitutes the application of NBS at a global, continental and regional scale. Extensive literature was made to assess; NBS type, location, start and ending period of implementation, status, and level of effectiveness, recommendations set by researchers, and insight for future applications.

The comprehensive review revealed that there are only a few scientific publications, hence, grey and non-scientific literature need to be included. Only four papers included a quantitative assessment for evaluating the effectiveness of NBS targeting drought. However, the continental and regional performance of NBS is not mentioned. Therefore, a common effectiveness evaluation framework shall be created to give policymakers a clear view of the different NBS’s. Furthermore, a more collaborative approach, including different stakeholder groups, is recommended, with specific attention to the local communities. In Flanders, most projects are in the pilot project stage. Moreover, the few successfully implemented projects are only very local and have a long realization time which the earlier limits to acquire visible impact at a larger scale. Finally, the loss of wetlands at a global scale and in Flanders (70% are lost), increases the vulnerability of catchments to drought. Therefore, future research should increase the evidence base and implementation of NBS, such as wetlands, in Flanders.