A global synthesis of field measurements shows that coastal habitats – particularly coral reefs and mangroves, can be physically and economically effective at protecting coastlines.
During my post-grad thesis on coastal risks and adaptation, I came across a port in India situated behind an island covered with mangroves. Despite being within the tropical cyclone belt, the port had no hard structures in place for its protection. In my study, I quantified the contribution the mangroves made (over and above the presence of the island) in protecting the port from cyclone waves.
A few months later, I was able to visit the port and present my findings. During our conversation, the managers recounted the devastation they had seen in a nearby city from a cyclone a few years ago. While they knew the island was an important barrier, they admitted they had not – until then, considered the value of the mangroves on it.
The world’s coastlines are becoming increasingly difficult to protect due to rising risks, and coastal habitats can help reduce this risk. At the same time, these habitats – which sometimes act as defenses, continue to degrade due to direct and indirect human pressures. To help adapt to these collective threats, there is great interest in understanding the contribution, and value of habitats in protecting coastlines. In a study, published today in PLOS ONE, the SNAPP Coastal Defenses Working Group synthesized field measures of the effectiveness of natural coastal habitats and, for the first time, tied these measures to the costs and benefits of restoration projects (also called nature-based defenses). Click here to read more.