Late rains and record low water levels in Cambodia's two main fresh water systems will affect food security and the livelihoods of millions, government officials and NGOs warn.
"We expect the impact to be very strong," said Nao Thuok, director of the Fisheries Administration, adding that low water levels along the Mekong and Tonle Sap rivers were already limiting fish production and migration.
Crucial spawning grounds in floodplains along the rivers remained dry. "The places where the fish usually lay their eggs do not have much water so the fish population will decrease a lot," he warned.
Approximately six million Cambodians or 45 percent of the population depend on fishing in the Mekong and Tonle Sap basins, the government's Inland Fisheries Research and Development Institute, reports.
The annual "flood" season of daily rain usually starts in July but began a month late, local agricultural surveyors say.
According to the Mekong River Commission, which monitors the river at throughout its member states - Cambodia, Thailand, Laos and Vietnam - this month's levels are among the lowest ever for August. At the port of Phnom Penh, the Mekong plunged to 5.36m on 23 August, against more than 7.5m the same time last year and more than 8.5m in 2000.
Low rice productivity
Not only the fisheries sector is suffering, however.
Rice farmer Meas Chan Thorn in western Pursat Province was only able to plant last week, a month behind schedule, because of the late rains, and predicted yields would be halved.
"It's so difficult for us farmers in Cambodia because we depend entirely on the weather," the 67-year-old said.
According to the UN Food and Agriculture Organization (FAO), Cambodia could experience a 22 percent drop in rice output this year - from 7.6 million MT in 2009 to 5.9 million MT in 2010.
Rice is Cambodia's main crop and its harvesting requires more water than other crops. According to the UN World Food Programme, more than 85 percent of the country's rice production is rain-fed.
Photo: Harry Nesbitt/IRRI
|Female farmers hand treshing rice in Cambodia|
Prom Tola, a consultant for Phnom Penh-based Agricultural Development International, who is surveying farmers in Siem Reap Province, said there had been a rise in the number of rural people from Siem Reap leaving for Thailand in search of seasonal labour.
Som Sitha, who monitors marine life for the NGO Conservation International, said Mekong residents were finding the river levels increasingly unpredictable.
"They complain that it's getting lower every year, especially the last few years, and they say it's preventing them from getting enough fish."
But while observers attribute low river water levels to atypical rainfall patterns this year, others cite upriver dams as the real cause.
Environmentalists blame an increasingly shallow Mekong on China, accusing Cambodia's powerful northern neighbour of hoarding water in its upriver dams.
To date, four dams have been built along the Chinese stretch of the Mekong, with nine more under way or awaiting construction downstream in Laos and Cambodia.
However, according to the Mekong River Commission, the upstream dams have yet to influence downstream water levels.
"There is no doubt that upstream dams, when they do come fully on-line, will have an impact on the water levels, as well as generate other environmental and social concerns," Damian Kean, a spokesman for the Mekong River Commission, said.
"However, at present there is no evidence that Chinese upstream dams are operating at a sufficient intensity to cause these low water levels in Cambodia," he added.
More than 60 million people in the lower Mekong basin rely on the river for food, commerce and transportation, according to the Mekong River Commission. The group says 80 percent of protein consumed by Mekong residents comes from the river.