Shelter from the storm? Use and misuse of coastal vegetation bioshields for managing natural disasters

Vegetated coastal ecosystems provide goods and services to billions of people.  In the aftermath of a series of recent natural disasters, including the Indian Ocean Tsunami, Hurricane Katrina and Cyclone Nargis, coastal vegetation has been widely promoted for the purpose of reducing the impact of large storm surges and tsunami. This paper reviews the use of coastal vegetation as a “bioshield” against these extreme events. The authors aim to alter bioshield policy and reduce the long-term negative consequences for biodiversity and human capital. The paper begins with an overview of the scientific literature, in particular focusing on studies published since the Indian Ocean Tsunami in 2004 and discusses the science of wave attenuation by vegetation. The authors then explore case studies from the Indian subcontinent and evaluate the detrimental impacts bioshield plantations can have upon native ecosystems, drawing a distinction between coastal restoration and the introduction of exotic species in inappropriate locations. Finally, the authors place bioshield policies into a political context, and outline a new direction for coastal vegetation policy and research.