Yellow River Flooding in China Caused by Human Intervention, Not Mother Nature
Researchers from Washington University in St. Louis have linked the deadly floods of China's Yellow River to a widespread pattern of human-caused environmental degradation and related flood-mitigation efforts that began changing the river's natural flow nearly 3,000 years ago.
Over the years, Mother Nature has taken the heat for massive flooding along the Yellow River, including the catastrophic event of AD 14-17 that likely killed the 9.5 million people in its path. Now, new research shows that it's humans that are to blame.
"Human intervention in the Chinese environment is relatively massive, remarkably early and nowhere more keenly witnessed than in attempts to harness the Yellow River," lead author and archaeologist T.R. Kidder said in a news release.
"In some ways, these findings offer a new benchmark for the beginning of the Anthropocene, the epoch in which humans became the most dominant global force in nature."
Humans attempted to tame the Yellow River, known in China as the "River of Sorrow" and "Scourge of the Sons of Han," using flood-control systems such as levees, dikes and drainage ditches. Little did they know that their efforts were futile and only worsened the situation.
As they built levees higher, the previously stable Yellow River only became more dangerous.
"New evidence from China and elsewhere show us that past societies changed environments far more than we've ever suspected," Kidder said. "By 2,000 years ago, people were controlling the Yellow River, or at least thought they were controlling it, and that's the problem."
Kidder's research, co-authored with Liu Haiwang, senior researcher at China's Henan Provincial Institute of Cultural Relics and Archaeology, is based on analysis of sedimentary soils deposited along the Yellow River "over thousands of years," according to the release.
It also includes data from the team's digs at the sites of two ancient communities in the lower Yellow River flood plain of China's Henan province. Though ancient levees are difficult to spot with the untrained eye, geologists were able to confirm the site's sedimentary history using a number of precise tools.
"It's easy to see the trap they fell into: building levees causes sediments to accumulate in the river bed, raising the river higher, and making it more vulnerable to flooding, which requires you to build the levee higher, which causes the sediments to accumulate, and the process repeats itself," Kidder explained.
The research was published this week in the Journal of Archaeological and Anthropological Sciences.