Mangroves of Vietnam: Historical development, current state of research and future threats

Vietnamese mangroves are among the most productive and biologically important ecosystems of the world; providing habitat/nursing grounds for commercial and non-commercial fish species, food, medicine, building materials/fuel for local communities, as well as carbon storage (blue carbon) and coastal protection from storm events. However, Vietnam's mangroves have been lost in recent decades (∼38%) or degraded, predominantly driven by herbicides during the Vietnam War and later by conversion to aquaculture and coastal development, although there has been a recent slowing of this degradation as a result of restoration and protection schemes. This review article discusses the principal factors which influence mangroves in Vietnam including climate and climate change, hydrology, soil and topography, and anthropogenic factors such as aquaculture expansion, illegal logging, damming, pollution), which requires special attention. We further discuss the important role that Vietnamese mangrove forests play an in the socio-economic development of the country, even though the exploitation and protection of mangrove forests in many provinces are often uncontrolled. We discuss successful management practices including co-management models for mangrove restoration, which have been a success in Vietnam. Conservation and rehabilitation process of mangrove forests by various national and international agencies are still on-going and the success of such activities is influenced by various socio-economic, political as well as environmental factors. Further challenges in effective mangrove management arise due to climate change, which accelerates high atmospheric CO2, increased air temperature, sea level rise, storminess, ocean currents and alterations in precipitation regime. Recent developments in remote sensing applications can be utilized to improve the mapping and monitoring the changes in mangrove ecosystems in Vietnam thereby improving the effective management of mangrove forests.