London/Beijing, Aug 14 (IANS) An international team of researchers has discovered unique “graffiti” on the walls of a cave in central China that describes the effects drought had on the local population over the past 500 years.
The information was contained in the inscriptions on the walls of Dayu Cave in the Qinling Mountains of central China.
It describes the impacts of seven drought events between 1520 and 1920, painting an intriguing picture of how societies are affected by droughts over time.
“In addition to the obvious impact of droughts, they have also been linked to the downfall of cultures – when people do not have enough water, hardship is inevitable and conflict arises,” explained Dr Sebastian Breitenbach from University of Cambridge’s department of earth sciences.
In the past decade, records found in caves and lakes have shown a possible link between climate change and the demise of several Chinese dynasties during the last 1800 years, such as the Tang, Yuan and Ming Dynasties.
The climate in the area around the cave is dominated by the summer monsoon, in which about 70 percent of the year’s rain falls during a few months.
When the monsoon is late or early, too short or too long, it has a major impact on the region’s ecosystem.
The results, published in the journal Scientific Reports, also point to potentially greatly reduced rainfall in the region in the near future, underlying the importance of implementing strategies to deal with a world where droughts are more common.
According to the inscriptions in Dayu Cave, residents would come to the cave both to get water and to pray for rain in times of drought.
An inscription from 1891 reads, “On May 24th, 17th year of the Emperor Guangxu period, Qing Dynasty, the local mayor, Huaizong Zhu led more than 200 people into the cave to get water. A fortune-teller named Zhenrong Ran prayed for rain during the ceremony”.
Another inscription from 1528 reads, “Drought occurred in the seventh year of the Emperor Jiajing period, Ming Dynasty. Gui Jiang and Sishan Jiang came to Da’an town to acknowledge the Dragon Lake inside in Dayu Cave.”
While the inscriptions are business-like in tone, the droughts of the 1890s led to severe starvation and triggered local social instability, which eventually resulted in a fierce conflict between government and civilians in 1900.
The drought in 1528 also led to widespread starvation, and there were even reports of cannibalism.
“There are examples of things like human remains, tools and pottery being found in caves, but it is exceptional to find something like these dated inscriptions,” noted lead author Dr Liangcheng Tan from the Institute of Earth Environment at the Chinese Academy of Sciences in Xi’an.
The Qinling Mountains are the main recharge area of two larger water transfer projects and the habitat for many endangered species, including the iconic giant panda.
“Thus, it is imperative to explore how the region can adapt to declining rain levels or drought,” Breitenbach concluded.