Coastal habitats are being increasingly used and managed for protection against storms, coastal flooding and erosion. However, little information has been synthesized to identify when, where and how these nature-based defenses are successful and cost effective.
To fill this information gap, the SNAPP Coastal Defenses Working Group released a new study in, PLOS ONE, that analyzes data from projects and field measurements in coastal habitats world-wide. By synthesizing data on wave reduction, restoration costs, and protection benefits, and comparing the information to costs associated with alternative structures, Narayan et al. demonstrate the physical effectiveness of natural defenses as well as their costs and benefits.
"Gathering this data and synthesizing it, revealed to us the wealth of evidence that exists, that healthy coastal habitats can provide a coastal protection service. Importantly, it also made me appreciate the nuances we need to consider in terms of measuring effectiveness and costs, especially when we decide to use and manage coastal habitats for this purpose."
-Siddharth Narayan, NCEAS/SNAPP Postdoctoral Associate
The authors found that coastal habitats -- especially coral reefs and mangroves -- have significant potential to reduce wave heights and protect shorelines. They also report that under the right conditions, restoration projects can be a highly cost effective alternative to hard structures, such as submerged breakwaters.
The study highlights the immediate need for more measurements and observations of the effectiveness and cost effectiveness of restoration projects that are intended for coastal protection. Therefore, along with this new research, the Coastal Defenses Working Group is developing an online database of the studies that have measured the effectiveness of restoration projects.
The Effectiveness, Costs and Coastal Protection Benefits of Natural and Nature-Based Defences
S. Narayan, M. Beck, B. Reguero, I. Losada, B. Van Wesenbeeck, N. Pontee, J. Sanchirico, J. Ingram, G. Lange, K. Burks-Copes
PLOS ONE, 2 May 2016 DOI: 10.1371/journal.pone.0154735
Learn more about the SNAPP Coastal Defenses Working Group
This research was integrated in to the World Bank's Wealth Accounting and Valuation Of Ecosystem Services Report