Editorial: Special issue: Nature-based solutions for reducing disaster risk: What is the evidence?

Nearly two decades ago, the Indian Ocean tsunami created a devastating human tragedy, leaving many questions in its wake as to the role that mangroves may have played in saving lives and livelihoods. Over the following decade, these questions led to the creation of a new field of study: the role of ecosystems in disaster risk reduction, or Eco-DRR. After 2020, Eco-DRR became quasi-synonymous with ‘Nature-based Solutions for disaster risk reduction’, with a few notable differences. What changed as a result of the Indian Ocean tsunami was an increased awareness that ecosystems could - and should - be part of discourse and portfolios of investments in disaster risk reduction (DRR). Over the next two decades, this awareness grew in three phases: 1) 2005–2014: the ‘convincing stage’; 2) 2015–2020: the ‘mainstreaming stage’ 3) 2020: ‘the blue-printing stage’. This collection of articles highlights research on the evidence of the effectiveness of ecosystem approaches for DRR, while addressing the above question: “how to implement”?