In China, around 270 million people are living on "sinking land". As per a study in the journal Science, nearly half of the major Chinese cities are rampantly sinking, increasing the risk of deadly floods.
As per the study in Science, 45 percent of China's urban areas which consists of 29 percent of the country's population are sinking faster than three milimetres per year.
With nearly half of China's urban cities sinking, the study added that around 16 percent of the land, which had around 67 million people, is sinking faster than 10 millimetres each year.
Why Is China's Land Sinking?
As per the study published in Science, China's land is sinking due to the ongoing subsidence crisis. As per the authors of the study, one of the major reasons for the subsidence crisis is the weight of buildings and infrastructure.
Apart from heavy buildings, excessive pumping of groundwater, oil drilling and coal mining are also adding to the rampant rate of subsidence since al of these activities create empty space underground which causes soil or rocks to collapse.
Along with this, rising sea levels due to climate change and global warming only add to the crisis. As per the study, the rising sea levels and the fast sinking of land puts the people at risk for deadly flooding.
As per the study, the cities most at risk are - Beijing, Tianjin, Changchun, Zhengzhou, Pingdingshan, Kuming, Nanning, Wenzhou, Harbin and Fuzhou.
In Tianjin, thousands of residents were evacuated last year from high-rise heavy apartment buildings after the streets outside split apart. However, another problem noted by the authors is that within the cities at risk, the level of sinking is uneven.
When the sinking is uneven, whatever is built on top of it is at risk of damage.
Is China The Only Country Where Land Is Sinking?
No. Along with China, the United States is also facing a similar problem. Satellite research shows that the US East Coast is also sinking.
One of the major reasons for the East Coast sinking is the over pumping of ground water.
Research from the Virginia Tech and the US Geological Surgery shows that the coastal areas are at risk of sinking and rising sea levels are accelerating the rate at which land is sinking.
What Is The Solution To A Subsidence Crisis?
While th solution to resolve the crisis may take years, the researchers have stated that limiting groundwater extraction is a start. Citing a case study from Japan, the researchers added that groundwater management over the years have stabilised the subsidence rate in the country.
Another solution would be to inject water into the depleted aquifers to ensure they are recharged. Lastly, one must adapt to the change, especially the rising sea levels that have been caused by climate change as well as sinking land.
