A World Biosphere Reserve, Can Gio mangrove forest is calling for protection
Vietnamese environmentalists feel that the overlapping management mechanisms at play in the conservation of the Can Gio mangrove forest in HCM City are slowly but surely threatening the very existence of this world’s biosphere reserve.
Under instruction from the HCM City People’s Committee back in 1978, locals were encouraged to plant mangroves in the Can Gio forest. They were basically advised the more the better.
This 30,000ha mangrove forest in the Can Gio District, less than 60km east of HCM City, is now an essential feature of the area and a vital part of the ecosystem.
The forest is integral in the reduction of salt water intrusion in the agricultural production areas of Can Gio District and neighbouring regions. In addition to this, it acts as an air pollution filter and cleans out sediments from the estuary, trapping and preventing HCM City’s solid waste from being discharged into the sea.
The forest is also an intrinsic aid in the reduction of storm damage to the city, and acts as a barrier to the harsh winds, said the Mangrove Ecosystem Studies Centre.
During the American War, the forest was severely damaged by defoliants and herbicide sprays, so the city and many locals went to great lengths to rehabilitate the area and diversify its ecosystem between 1978-84.
These efforts paid off in 1991 when the Government designated Can Gio an environmental conservation site. In January 2000, the United Nations Educational, Scientific and Cultural Organisation (UNESCO) admitted the forest to its World Network of Biosphere Reserves and took control of its management.
Yet despite the best efforts of everyone to preserve the area, the forest’s mangroves are still dying in places from natural causes. The Can Gio Mangrove Management Board suspect landslides and lightening strikes as being the primary culprit, with pests an additional yet less significant menace.
Attending a recent seminar to discuss measures to save the deteriorating mangroves, participants were shocked to learn that a staggering 60 per cent of the forest had died.
This time humans were being blamed for the destruction of the 25ha of forest.
The construction of roads near the area in 2002 interrupted the supply of water to some areas of the forest, resulting in a shortage to some sections and an oversupply to others.
Shrimp farming has also played an active role in the destruction of the forest, with close to 1,000 families overcrowding an area of 3,000 ha with enclosures and farm irrigation systems.
Cat Van Thanh, vice-head of the Can Gio Mangrove Management Board, recommended immediate action be taken to protect the forest. He believes the solution is to isolate areas infected with pests, then clear out the dead trees to prevent any further spread throughout the forest.
Thanh proposed additional measures be taken, including the planting of different species of trees so as to diversify the forest and utilise the nutrients in the soil.
The original programme designers from 1978 did not correctly calculate the density of the mangroves or anticipate their rate of growth, nor did they consider whether other types of trees would be best suited to the soil in order to balance the ecosystem.
Seminar participants felt that the HCM City People’s Committee should revoke its 1999 decision to restrict the thinning of mangroves in the forest.
Further suggestions included the digging of canals in shrimp farm areas to induce water flow and bring much needed nutrients to the mangroves.
Studies indicate that the area is an extremely sensitive ecosystem and any changes to the forest should be conducted under strict supervision.
With so many suggestions and recommendations made, you would think that officials would be hard pressed to choose and appropriate measures to test. This however is not the case, as none of the proposed solutions can be implemented due to restrictions placed on the Can Gio mangrove forest.
With the HCM City People’s Committee originally responsible for forest protection decisions, management is now in a real quandary because of the new UN status. As the area is part of the UNESCO biosphere reserve, regulations dictate that the forest be kept intact, and the Committee not intervene. Now only time will tell if Can Gio mangrove forest can survive this bureaucratic nightmare and regain its once proud status.
VNS - (22/04/2005)