Study on mangrove degradation and select species for mangrove rehabilitation in Xuan Thuy National Park, Nam Dinh province
In the framework of the project “Restoration and conservation for degraded mangroves in Xuan Thuy National Park, Nam Dinh province”, in November 2019, Center for Nature Conservation and Development (CCD) with support from mangrove experts and Xuan Thuy NP implemented a study on mangrove degradation to select species to restore degraded areas Xuan Thuy National Park.
The study implemented by establishing transects and sampling plots in the study areas. At least 3 transects were established, and 3 sampling plots (400m2 each) were setup in each transect. According to survey results, the key mangrove species communities, including: Aegiceras corniculata ( L.) Blanco – Sonneratia caseolaris (L.) Engl.; Kandelia obovata Sheue, H.Y. Liu & J. Yong – Aegiceras corniculata (L.) Blanco; S. caseolaris (L.) Engl.; A. corniculata (L.) Blanco – K. obovata Sheue, HY Liu & J. Yong – Avicennia marina (Forsk.) Vierh – S. caseolaris (L. ) Engl.; K. obovata Sheue, HY Liu & J. Yong – Rhizophora stylosa Griff. The results also indicated that approximately 7.5km of mangroves in Con Lu island were eroded by waves and 78.37 ha K. obovata Sheue, HY Liu & J. Yong – A. corniculata (L.) Blanco in the same island were degraded by pests and diseases on K. obovata trees. According to the study, two species of S. caseolaris (L.) Engl. and R. stylosa Griff also were recommended as key species to recover the degraded areas.
The mangrove forest in Xuan Thuy National Park is the first Ramsar site in Vietnam and serves as key area for migratory birds and important prawning ground for fisheries. The mangrove is also a strategic coastal protection belt for Red River estuary that prevent intrusion of the seawater and protecting the sea dyke. More importantly, the mangrove is providing livelihoods for thousands of people in the buffer zone and it is an important ecotourism site in Nam Dinh province and the Red River Delta. However, due to the impacts of climate change, sea level rise, especially the impacts made by human such as over fishing and exploitation of aquatic resources made huge impact on mangroves. Also the changes in salinity and tidal are also seriously impact the mangrove as many area were degraded, many tidal areas where shorebird and migratory species are feeding now are converted into shrimp ponds, and intensive mussel farming areas. The conversion causing loss of habitats and feeding grounds of many endangered species such as the critically endangered spoon-billed sandpiper Eurynorhynchus pygmeus, the black-faced spoon-billed Platalea minor, Nordmann’s greenshank Tringa guttifer, Chinese egret Egretta eulophotes and many other threatened birds.
CCD will continue to work with mangrove experts and Xuan Thuy National Park to pilot mangrove nursery and pilot the restoration planting for degraded area. In addition, CCD will continue its communication activities for local community to raise awareness and provide technical support on mangrove nursery and planting techniques, so that local community could engage and participating in mangrove forest conservation and restoration effort in Xuan Thuy National Park.