Blue and Green: A combination of human-caused environmental degradation and efforts to control the great Yellow river in China, made almost 3,000 years ago, may be responsible for flooding that killed millions and led to the fall of an empire, according to new research.
In what could be considered a grim lesson from history of the importance of responsible land use, archeologists in China have found evidence that societies changed their environments much earlier than previously believed.
"Human intervention...