Vietnam news 12 Oct 11;
HA NOI — Representatives of Xuan Thuy National Park and scientists from Ha Noi-based national university's centre for natural resources and environment studies (Cres) have been struggling with a pilot project aimed at growing taller, stronger mangroves in the park.
The park's current mangrove forest (Sonneratia ceseolaries) has been devastated by rising sea levels along the northern coastal province of Nam Dinh in recent years.
Experts estimate that 30ha out of 1,000ha of mangroves, as well as 10ha of casuarina trees, have withered away due to a 40cm increase in the water level over the past two years.
"The number of bird species – which formerly stood at 215 and included black-faced spoonbills, western white pelicans, black-headed gulls and redheaded egrets – has dwindled," said the park director, Nguyen Viet Cach.
"Despite our efforts, the problem has been getting worse over the last two years, and we need to start a new project that will result in larger mangroves," he said.
Scientists from Cres in co-operation with the park administration have been developing a bigger and taller mangrove species, sonneratia apetala, in the park's sapling garden since 2004.
The first plants have shown rapid growth even in the saltier water and colder weather that now characterises the park's environment.
"I grew the first seeds of sonneratia apetala at the sapling nursery in the park and it reached a height of 8m with big dense roots after just two years," said associate professor Phan Nguyen Hong.
"My colleagues and I have also tested exotic plants for seven years and results prove that the sonneratia apetala mangrove can protect the park from devastation caused by rising sea levels," Hong, who is former deputy director of Cres, explained.
The 79-year-old scientist, who has extensively studied wetland ecological systems, said the sonneratia apetala mangrove had grown in the southern province of Ca Mau in the past, but it died out as a consequence of Agent Orange during the American War in the early 1960s.
Researchers at the park's nursery also plant various mangrove species such as kandelia obovata, rhizophora stylosa, bruguiera gymnorrhyza and acanthus Ilicifolius, aegiceras, which have helped protect sea dike systems in the park from storms and floods since 2005.
Hong said there are 78 mangrove species in Viet Nam, which could help contribute to the restoration of the mangrove forests.
The 7,100-ha forested wetlands, about 150km south of Ha Noi, are home to a wide range of migratory waterfowl and other species. The park is a Ramsar Convention site – a wetland area recognised internationally for its ecological importance.
As a result of rising sea levels, managers of the park, which is recognised by UNESCO as a Red River Biosphere Reserve, have had to raise the height of dams and roads by between 0.5m and 1m, at a cost of VND7 billion (US$350,000) over the past two years.
The park has been seeking $6.7 million to finance an 80ha reforestation, introducing bigger mangrove species over a three to five-year period. — VNS
