Melaleuca forest and wetland management in the Mekong Delta
Mr. Duong Van Ni
Farming Systems Research and Development Institute, Cantho University, Vietnam, Can Tho City, Vietnam. Tel: 84 71 832395. Fax: 84 71 831270.
Dr. Roger Safford and Dr Edward Maltby
Royal Holloway Institute for Environmental Research, Royal Holloway University of London, Huntersdale, Callow Hill, Virginia Water GU25 4LN, UK. Tel: 44 1784 477404. Fax: 44 1784 477427. Email: r.safford@rhbnc.ac.uk.
Abstract of paper presented at the conference Environmental Change and Vulnerability: Lessons from Vietnam and the Indochina Region, Hanoi, Vietnam, April 4-5th 1998.
The people and environment of the Mekong Delta have in recent years been subjected to rapid and extreme changes, affecting urban and agricultural areas and natural ecosystems. Poverty and landlessness are common outcomes. To survive, many turn to the already diminished natural resource base, leading to environmental degradation, increased pressure on natural ecosystems, and further poverty.
One means to combat this cycle is to attempt to avoid the need for farmers to sell their land, through sustainable income-raising by diversification of income sources. Management of the tree Melaleuca cajuputi — already a component of the local wetland ecosystem — provides one such source.
Melaleuca provides many direct benefits such as wood. We show that Melaleuca can help to improve the quality of water in the acid sulphate soil areas typical of the Mekong Delta, specifically by raising its pH and reducing the concentrations of toxic metal ions; given the paramount importance of water resources in the delta, this result has implications for the value of natural ecosystems.
Several possible agents of the change in water quality are being investigated. Preliminary results of experiments now underway suggest that rain that has passed through the Melaleuca canopy or flowed down the trunks of Melaleuca trees does not affect the pH of surface water. However, leaf litter of the Melaleuca forest appears to play a vital role in improving water quality. The importance of living plant matter has not yet been tested.
The viability of a Melaleuca-and-rice farming system designed to capitalise on the multiple benefits of Melaleuca is being tested in a demonstration plot; active and successful participation by farmers, and farm-scale improvements in water quality, suggest that farming systems using this this model can be practicable, economical and sustainable.