Natural barriers to natural disasters: Replanting mangroves after the tsunami
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E. B. Barbier


The Indian Ocean tsunami disaster of December 2004 has increased interest in replanting degraded and deforested mangrove areas in Asia to improve coastal protection. Evidence from Thailand suggests that concern over mangrove deforestation by shrimp farms (aquaculture) is an important motivation for many coastal households to participate in mangrove rehabilitation. However, successful re-establishment and management of mangroves as effective coastal barriers will require developing new institutions and policies, and must involve coastal communities in Thailand and other Indian Ocean countries in the conservation and protection of their local mangrove forests.

Main Results and Conclusions:
  • Determining whether or not mangrove reforestation efforts are going to be successful involves investigating many aspects:
    • Environmental injustice is commonly associated with shrimp farming: “…those most responsible for much of the past mangrove destruction are unlikely to be involved in replanting and restoration efforts. Instead, most current replanting schemes depend on the participation of the coastal communities most affected by the loss of local mangrove forests” (125).
    • The FAO underestimated the remaining mangrove forests in Thailand in comparison to Thailand’s Royal Forestry Department studies, for example, ~2500 km2 vs. ~1650 km2 for 2004 (125).
    • External costs associated with aquaculture operations cause severe problems for local communities: water pollution, short production life spans leads to rapid coastal development and abandonment, no legal requirement to replant deforested areas, and large subsidies (126).
    • Open-access conditions impact mangrove deforestation: open-access causes mangrove habitats to be more vulnerable to illegal aquaculture as well as woodchip and logging operations. Additionally, open-access areas cause local peoples to have little say in what happens to the mangrove forests, despite depending on them for their livelihoods (126).
  • A summary of Thailand’s re-planting efforts is as follows (126):
    • “…past replanting programs in Thailand and other Asian countries have largely operated within the existing legal and institutional framework that does not require those most responsible for the mangrove deforestation…”
    • “…governments and/or nongovernmental organizations fund the rehabilitation plans, especially when this requires the acquisition of heavy equipment and engineering contractors to re-convert and prepare abandoned ponds and other degraded land for restoration.
    • “Local communities are generally restricted to supplying the labor for manual tasks such as tending nurseries, planting seedlings, and weeding.”
  • Local participation in mangrove re-planting efforts studied in four villages in Thailand from Barbier’s 2006 study indicated that men were more involved in re-planting efforts, as much as 62 hours per year was spent replanting in the Ban Gong Khong village, and that as little as 0% in the Ban Sam Chong Tai village wanted shrimp farms in the villages (Table 1, 128). “The results of the analysis confirm that the degree to which the households are dependent on mangrove-based activities for their incomes is a major factor determining whether households participate in mangrove rehabilitation schemes” (128).
  • Suggestions for sustainable mangrove management (cited in paper from Barbier & Sathirathai 2004) (129-130):
    • Remaining mangrove areas should be classified as either conservation areas or economic zones. Shrimp farms should be restricted to economic zones, but local communities that are dependent on mangrove ecosystems for subsistence living should be allowed access.
    • Establish community mangrove forests in both conservations and economic zones. Local management of mangrove forests in the form of user rights should be granted based on community management capabilities.
    • Co-management between local communities and the government should exist for community forests.
    • The government should provide complete support to local communities participating in mangrove conservation (i.e. technical, educational, financial).
Works Cited:

Barbier, E. B. 2006. Mangrove dependency and the livelihoods of coastal communities in Thailand. In: Hoanh CT, Tuong TP, Gowing JW, and Hardy W (Eds). Environment and livelihoods in tropical coastal zones: managing agriculture–fishery–aquaculture conflicts. Wallingford, UK: CAB International.

Barbier, E. B. and S. Sathirathai 2004. Conclusion of the study and policy recommendations. In: Barbier EB and Sathirathai S (Eds). Shrimp farming and mangrove loss in Thailand. London, UK: Edward Elgar.

FAO (UN Food and Agricultural Organization). 2003. Status and trends in mangrove area extent worldwide. Rome, Italy: Forestry Department. Forest Resources Assessment Working Paper 63.