Tropical logging harms downstream water quality

April 16 (UPI) — New research suggests even the most sustainable forms of logging in tropical forests can compromise water quality downstream.

Researchers from the University of Queensland and the Wildlife Conservation Society found commercial logging on the Solomon Islands is triggering large amounts of soil erosion, harming water quality and curbing access to clean drinking water.

The unsustainable rates of erosion, researchers argue, could leave large portions of logged land unable to support agriculture.

Tropical forests on the Solomon Islands are shrinking fast as a result of commercial logging. Ecologists and conservationists have documented the risks posed by forest-clearing. Logging can cause a range of environmental problems, scientists argue — problems beyond just the loss of habitat and carbon storage.

“When land-clearing extent reached 40 percent in our models, international standards for safe drinking water were exceeded nearly 40 percent of the time, even if best practices for logging were followed,” Amelia Wenger, postdoctoral researcher at the University of Queensland, said in a news release. “Loss of the upland forest will compromise local access to clean water essential for drinking, bathing, and household washing.”

Researchers are using their findings — published in the journal Environmental Research Letters — to inform residents of Kolombangara Island about the risks of continued logging. Conservationists are working with local organizations and government officials on the island to protect a large swath of forest.

“Previously people in Solomon Islands made decisions about logging from a selfish economic perspective,” said Ferguson Vaghi, local coordinator with the Kolombangara Island Biodiversity Conservation Association. “This study highlights that we also need to consider the impacts to the downstream environment.”

Scientists say future land management plans and other parameters governing sustainable levels of logging must account for the impacts of deforestation on erosion rates and water quality.