No link between deforestation and flooding, says report

In a move sure to cause major arguments in the conservation world, the UN Food and Agriculture Organisation (FAO) and the Centre for International Forestry Research (CIFOR) have released a report saying there is no link between deforestation and major floods.

The report, Forests and Floods: Drowning in Fiction or Thriving on Facts?, claims there is no scientific evidence to say that deforestation causes flooding.

“Government decision makers, international aid groups and the media are often quick to blame flooding on deforestation caused by small farmers and loggers,” said Patrick Durst, Senior Forestry Officer for FAO’s Asia and the Pacific Office. “The conclusion is not only wrong, scientifically, but such misguided views have in the past prompted governments to make life harder for poor farmers by driving them off their lands and away from the forests, while doing nothing to prevent future flooding.”

The report acknowledges that forests can play a role in minimising runoff that causes localised flooding, but concludes that there is no evidence that a loss of trees significantly contributes to severe widespread flooding.

The report flies in the face of conventional wisdom which states that forests and vegetation in general will slow the run off of water during heavy rainfall preventing rivers becoming deluged.

David Chowdrey, a spokesperson for WWF and former hydrologist for the Environment Agency, said he was “flabbergasted” that anyone could suggest there was no link between forest cover and flooding.

“If you deforest an area, you reduce the timelag for runoff so increase the chance of flooding downstream,” he told edie. “I find it incredible that anyone would advocate deforestation, nobody who understands hydrology would say that.”

He said the power and intensity of the flooding would be increased through the speed of the run off, while the topsoil of an area would also be removed increasing theload in rivers.

However, the FAO/CIFOR report says there is political interest in leaving the conventional wisdom unchallenged “as it allows governments to respond with logging bans and give the appearance to the public they are taking decisive steps to stop flooding.”

It goes on to say that “international agencies may also have a stake in maintaining the forest-flood myth as it helps in channelling aid funds to upland reforestation projects.”

According to the report, integrated approaches are needed which recognise the limitations of working only in uplands or only in lowlands.

“Politicians and policymakers should stop chasing quick fixes for flood-related problems and promote integrated watershed and floodplain management,” said David Kaimowitz, Director-General of CIFOR and one of the report’s authors.

David Hopkins

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