Maria Osbeck & Neil Powell, Straits Times 14 May 09;
THE horrors of Cyclone Nargis a year ago, and the Asian tsunami before that, have led to renewed interest in how mangroves can limit the impact of natural disasters. As images of devastated landscapes and bloated corpses appeared in the days and weeks after Nargis, environmentalists made their point: If Myanmar had kept the fringe of mangroves along its 3,000km coastline, the damage would have been less. Some of those who died - up to 140,000 people, by some counts - might have been saved.
Today, most governments acknowledge the importance of mangroves in dissipating the force of tides and waves caused by extreme events such as Nargis. Mangroves also serve as natural nurseries and feeding grounds for three-quarters of all commercially fished species in the tropics. Their unique root systems capture sediment and prevent erosion. They also filter out pollutants that would otherwise flow into the sea.
Mangrove restoration thus is more popular than ever before. Following Cyclone Nargis, Asean secretary-general Surin Pitsuwan had emphasised the role of mangroves. Before that, in the wake of the Asian tsunami, former United States president Bill Clinton hosted a meeting in New York to launch 'Mangroves for the Future', a multi-party project focusing on mangrove conservation in tsunami-affected countries. The Red Cross is funding major replantation efforts in Vietnam and Thailand, and the Japanese government is supporting mangrove plantations across Asia.
However, many of these attempts at mangrove restoration are deeply flawed. Mangroves are being planted in areas that never supported them in the first place. In Thailand, for example, the government has been very supportive of mangrove restoration, but replanting efforts often do not consider local ecosystems.
Mangrove forests are part of a larger coastal ecosystem that typically includes mudflats, seagrass meadows, tidal marshes and salt pans. They may be linked with inland forests, peat lands, and freshwater rivers and streams. Those restoring mangroves need to consider how new trees will affect existing ecosystems and whether suitable sites are selected.
In Thailand, mangroves have been planted on coastal mudflats, resulting in the loss of habitat and feeding grounds for migratory birds, shellfish and other shore life. Experience from the Philippines reveals that the survival rate of mangroves planted in unsuitable terrain like this is very low. In Sri Lanka, it has been shown that extensive planting of mangroves in lagoon areas has led to an overall reduction in fish productivity.
Then there are issues of land rights and livelihoods linked to the restoration of mangroves. Unclear land-rights systems and the zoning of coastal areas are major challenges to mangrove restoration in the long term.
Take, for instance, the Mahakam delta in East Kalimantan, which has become one of the wealthiest areas in Indonesia due to local shrimp aquaculture, as well as gas exploration in areas formerly covered by mangrove.
Here, shrimp-pond owners grow 'organic' white-spot shrimp in large-scale, low-intensity systems with little chemical input - a practice that allows them to command higher market prices as compared with shrimp from high-intensive, small-pond cultivation common elsewhere in Asia. This land-hungry enterprise has led to the loss of almost 80 per cent of the mangroves in the delta, though most of the area is officially classified as a conservation zone.
Meanwhile, companies drilling for natural gas in the Mahakam delta are compensating farmers for the loss of mangroves due to gas exploration. While only a small amount of mangrove loss is traced directly to gas exploration, the knock-on effects are far reaching. Local people who have customary rights to stands of mangrove are now clearing new areas in the hope of getting money from the gas companies. Also hoping to claim compensation, others are holding on to old shrimp ponds that have become unproductive rather than converting the land to other uses. Ambiguities and a lack of transparency have led to conflicts between farmers and companies, in addition to losses of natural assets.
It is important to acknowledge current land-use practices in designing mangrove restoration plans, to reduce conflicts and to support law enforcement to limit further conversion and ensure long-term sustainability of replanted areas.
The revival of interest in mangroves, following the devastation of Nargis, should now be harnessed in designing and implementing programmes that contribute to sustainable coastal resource management. Such solutions must consider the livelihoods of local people, as well as incentives for them to maintain existing natural assets.
Mangroves have many uses and many people benefit from them. It would be a great pity if the current enthusiasm for mangroves should falter due to a failure to reconcile conflicting aims. Mangrove restoration should contribute to the ecosystem and local communities - and not merely to impressive statistics on how many trees have been planted.
The writers are researchers with the Stockholm Environment Institute in Asia.
