Humans have been changing Chinese environment for 3,000 years

PART.2

Implications for modern river management

Slowly, over thousands of years, human intervention began to have a dramatic impact on the river's character. Periodic breaches of the levee system led to devastating floods, with some shifting the river's main channel hundreds of miles from its initial course.

A census taken by China in A.D. 2 suggests the area struck by the massive A.D. 14-17 flood was very heavily populated, with an average of 122 people per square kilometer, or approximately 9.5 million people living directly in the flood's path.

Boxed section of Image A shows the first stage of a bank/levee exposed in the excavation at Anshang. Image B offers a closer view of the boxed section showing mixed and loaded/rammed sediments near the base of the bank/levee. Credit: Journal of Archaeological and Anthropological Sciences

"The misery and suffering must have been unimaginable," Kidder said.

Historical accounts indicate that communities hit by the flood were soon in complete disarray, with reports of people resorting to banditry to obtain food and stay alive. By A.D. 20-21, the flood-torn region had become the epicenter of a popular rebellion, one that soon would spell the end of the Western Han Dynasty's five-century reign of power.

"The big issue here is that human beings clearly changed the environment, and that these changes had real consequences for human history," Kidder said. "It happened in the past and can happen again."

While the research offers new insight into Chinese history, it also has interesting implications for modern river management policies around the globe, such as those causing similar flooding problems along the Missouri and Mississippi rivers in the United States.

Map showing historically identified courses of the Yellow River and its historic mega-deltas. The 1938–1947 course evolved after the dykes were destroyed to (unsuccessfully) prevent Japanese forces from advancing across the Central Plains. Credit: Journal of Archaeological and Anthropological Sciences

"To think that we can avoid similar catastrophe today due to better technology is a dangerous notion," he said. "When in doubt, bet on Mother Nature because physics will win every time."

"Human-caused environmental change is nothing new," Kidder said. "We've been doing this for a very long time, and the magnitude of change is increasing. Unlike ancient China, where human mistakes devastated a single river valley, we now have the technology to make mistakes that can cause devastation on a truly global scale."