Through an extensive reforestation plan, China managed to halt the advance of soil desertification by planting billions of trees.
Since 1981, 78 billion trees have been planted in what is called the “Great Green Wall” of the Three Northern Regions, among other projects.
The goal was to combat soil erosion and reduce sandstorms coming from the desert.
However, more than 40 years later, a study revealed that this massive intervention now has a negative side effect.
Apparently, this “Forest Belt” altered precipitation patterns and now causes water scarcity in areas where almost half of the population lives.
The project, as announced by the Chinese state press last year, was finally concluded in 2025, but its impact on droughts is concerning.
China shows the hidden problem of planting too many trees
The Great Green Wall of China has trees planted over an area of 116,000 square miles.
Thanks to this project, the country’s forest cover increased from 10% in 1949 to approximately 25% in 2024.
However, a new study published in the journal Earth’s Future revealed unforeseen consequences for water distribution.
This was discovered by scientists from Tianjin University, China Agricultural University in Beijing, and Utrecht University.
Apparently, between 2001 and 2020, the increase in vegetation reduced water resources.
This reduction affected both the eastern region influenced by the monsoon and the arid region of the northwest.
These areas represent approximately 74% of the country’s total area, according to Live Science.
This is because greening efforts like the Great Green Wall, among others, increased evapotranspiration.
This term combines evaporation and transpiration, the process by which plants release water vapor through tiny pores known as stomata.
The study also analyzed other planting initiatives:
- Grain for Green Program (started in 1999)
- Natural Forest Protection Program (started in 1999)
- Three Northern Regions Forest Belt (since 1978)
In China, humidity shifted
“These changes caused alterations in precipitation, directing more moisture towards the Tibetan Plateau, which recorded an increase in water availability,” the study authors wrote.
“In contrast, eastern and northwestern China experienced a decrease in water availability due to more trees, with the northwest being the most affected region due to the significant moisture shift towards the Tibetan Plateau,” the researchers added.
The authors noted that certain transitions between zones influenced evapotranspiration, precipitation, and water availability at different rates.
The transformation of grasslands into forests increased evapotranspiration and precipitation.
But this transformation had a negative impact on water availability.
Today, water availability in China is not evenly distributed in relation to its population.
Northern regions concentrate approximately 46% of the population and more than half of the arable land, but only have 20% of the water resources, according to the study.
The authors argue that these altered hydrological cycles must be considered when planning future reforestation strategies in the country.
“Our findings highlight that changes in land cover can redistribute water resources between regions,” the authors concluded.
“Understanding these effects is crucial for planning sustainable land and water management in China,” the researchers added.
