Replanting forests in China is a great initiative but it can also prove to be disastrous for water management. Kai Schwärzel, Author provided
For the first time, China has hosted a major global event on desertification and land degradation, the Cop-13, United Nations Convention to Combat Desertification. The event took place in Ordos, in Inner Mongolia, a region known for its water-limited environments.
Such areas (commonly referred to as drylands) occupy about half of the planet and are often sensitive and prone to change because of limitations in water and extreme temporal variability in rainfall. Drylands are home to more than a third of the world’s population.
China has successfully implemented various afforestation programmes over the year to make drylands viable for its economy, and will continue until 2050. But, while planting more trees will further reduce discharge, it will also make China’s water crisis worse, as more trees need more water to grow.
China produces food for a fifth of the world´s population with only 7% of the world’s arable land, as 65% of its cultures are situated in the dryland region of northern and north-western China. The Loess Plateau is part of this dryland region, an area of the size of France. Loess is a wind-blown sediment, transported by wind from the Gobi desert for millenia.
The Loess Plateau is the cradle of the Chinese civilisation because the soils formed on Loess are very fertile and easy to farm. But Loess soils are extremely prone to erosion by water and wind. Centuries of mismanagement resulted in degenerated land and in huge sediment loads in the Yellow River. It’s estimated more than two thirds of the Loess Plateau Region is affected by soil erosion. Up to three Gigatonnes per year of sediment load was observed in the Yellow River in the late 1950s.