Collapse of Advanced Liangzhu Culture – “China’s Venice of the Stone Age” – 4000 years ago due to climate change

About 5,300 years ago, an ancient civilization emerged in eastern China, building a magnificent city perhaps never seen before in all of Asia, not even in the whole world.

The ruins of Liangzhu, which appeared along the banks of the Yangtze River Delta in eastern China, show many signs of social, cultural and technological progress of the period, especially in agriculture and aquaculture.

At the same time, sophisticated architectural features, including clever hydraulic engineering that enabled canals, dams, and water reservoirs, led to the allusion to Liangu being the Neolithic “Venice of the East”. However, none of these marvels lasted.

After 1000 years of innovation, the Liangju culture mysteriously collapsed some 4,300 years ago, and the ancient city was suddenly abandoned.

The reason for this was never understood, although many have suggested that some form of catastrophic flooding led to the sudden collapse.

“A thin layer of clay was found on the preserved ruins, which points to a possible connection between the demise of the advanced civilization and floods of the Yangtze River or floods from the East China Sea. No evidence could be found for human causes such as warlike conflicts,” explains Christoph Spötl, head of the Quaternary Research Group at the Department of Geology. “However, no clear conclusions on the cause were possible from the mud layer itself.”

Dripstones store the answer

Caves and their deposits, such as dripstones, are among the most important climate archives that exist. They allow the reconstruction of climatic conditions above the caves up to several 100,000 years into the past. Since it is still not clear what caused the sudden collapse of the Liangzhu culture, the research team searched for suitable archives in order to investigate a possible climatic cause of this collapse.

Geologist Haiwei Zhang from Xi’an Jiaotong University in Xi’an, who spent a year at the University of Innsbruck as a visiting researcher in 2017, took samples of stalagmites from the two caves Shennong and Jiulong, which are located southwest of the excavation site.

“These caves have been well explored for years. They are located in the same area affected by the Southeast Asian monsoon as the Yangtze delta and their stalagmites provide a precise insight into the time of the collapse of the Liangzhu culture, which, according to archaeological findings, happened about 4300 years ago,” Spötl explains.

Data from the stalagmites show that between 4345 and 4324 years ago there was a period of extremely high precipitation. Evidence for this was provided by the isotope records of carbon, which were measured at the University of Innsbruck. The precise dating was done by uranium-thorium analyses at Xi’an Jiaotong University, whose measurement accuracy is ± 30 years.

“This is amazingly precise in light of the temporal dimension,” says the geologist. “The massive monsoon rains probably led to such severe flooding of the Yangtze and its branches that even the sophisticated dams and canals could no longer withstand these masses of water, destroying Liangzhu City and forcing people to flee.” The very humid climatic conditions continued intermittently for another 300 years, as the geologists show from the cave data.


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