Livelihoods threatened in Peam Krasop Wildlife Sanctuary, Cambodia by migration of a sandy barrier beach
The Peam Krasop Wildlife Sanctuary is home to several small communes, where livelihoods rely on the natural resources of the surrounding mangrove forest. Residents of Old Peam Krasop village are highly dependent on green mussel cultivation, fishing and aquaculture, visible in a wide channel leading to the sea. The village has existed since 1964, currently with around 25 households accomodating 70 people. Only a thinning stretch of mangroves and a migratory sandy barrier beach protect the village from storms and rough seas.
Peam Krasop Wildlife Sanctuary Director Mr. Oul Rann has witnessed changes in the ecosystem over the recent decades and described some of the dramatic events. “Since the end of extensive mangrove deforestation for charcoal production during the 1990’s, livelihoods transitioned to more sustainable practices. Participatory replanting resulted in a healthy mangrove forest that supported wildlife habitats and more abundant fisheries” he said.
However, a 4 km long barrier beach, which moderates salinity levels and shelters much of the mangrove forest from high storm wave energy, has migrated landwards, leaving mangroves smothered by sand and dead in the ocean. Mud crab and clam populations, once abundant in mineral-rich mud of the mangroves, have lost large areas of habitat. An IUCN study found that migration of the barrier beach is accelerating and reached landward migration towards old Paem Krasop village at rates of 90 m per year between 2010 and 2011. Landward retreat has resulted in the loss of 0.60 km2 of mangrove forest since 1973.
The IUCN study highlights that even minor amounts of sea level rise can cause extensive landward barrier beach migration in such environments. Increases in storm frequency and intensity, associated with climate change, then cause rapid landward movement of the sand. Stable sediment dynamics are critical in preventing further barrier beach movement; excess sediment can smother aerobic mangrove roots, yet insufficient sediment can cause barrier beach erosion. In Peam Krasaop Wildlife Sanctuary sand and mud are sourced from four nearby rivers. Therefore upstream management must be prioritized in order to prevent further barrier beach migration and mangrove loss. Mitigation of impacts from Tatai River dam construction and usage of more sustainable sand mining techniques on the Koh Por River therefore have the potential to slow barrier beach migration. Revegetation of native plant species is also being explored as a beach stabilizing technique.
Local fisherman Seng Ly Hieng, 52 years old, has lived in the Old Peam Krasop village since 1986, and he explained that the barrier beach and mangroves provide fundamental protection for the village from storms. He noted that “further loss of the mangroves could leave the village uninhabitable”, remarking that there has been a noticeable increase in storm frequency and intensity since 2007" whereas the village once only experienced four months of heavy rain, Ly it now rains most days July through September, and bursts of particularly violent weather occur up to four times per night, damaging the stilted homes of the village”. Without the mangroves to mitigate the force of these storms, Old Peam Krasop will be on the frontline against the ocean. Ly Hieng explained that the villagers are also experiencing diminishing catches as the water channels around the mangrove forests widen through tree loss and deposition of sand into in the mangroves.
The village was abandoned once before due to a decline in marine resources: in 2004 all the residents moved to the mainland around Koh Kong, seeking better healthcare, education, and employment. However, the villagers failed to find sustainable employment. Some households returned to Old Peam Krasop to resume previous livelihoods, although in more recent years livelihoods have diversified to cater to the growing ecotourism industry.
Still, even ecotourism is threatened by local impacts to the mangrove ecosystem, where unstable beaches are now littered with dead tree stumps. If the residents are forced to leave the village once more, it is uncertain if they will be able to re-establish sustainable livelihoods around Peam Krasop Wildlife Sanctuary.
By Sun Kong, Joshua Hawkins and Brian Kastl