New research suggests the collapse of the Liangzhu and other stone age cultures along the Yangtze river delta around 4,300 years ago were the result of climate change. Situated on an estuary about 160 kilometres southwest of Shanghai and inhabited by an advanced civilization for about 1,000 years from roughly 3300 to 2300 BCE, China's "Venice of the Stone Age" had an elaborate water management system, with dams, reservoirs, and navigable canals, making it possible to cultivate large agricultural areas throughout the year. Discovered in 1936 and declared a Unesco World Heritage Site in 2019, it is the oldest known use of large hydraulic engineering structures in China, and one of the first examples of highly developed communities based on water infrastructure in the history of human civilisation.
     Samples of stalagmites from two caves southwest of the excavation site and a thin layer of clay at the ruins point to a period of massive anomalous monsoon rains between 4,345 and 4,324 years ago, leading to severe flooding of the Yangtze and its branches.
     Following the abandonment of Liangzhu, wet conditions continued intermittently for another 300 years.

Edited from The Independent (29 November 2021), Smithsonian Magazine (2 December 2021)