World Food Day: Turning salt-rich soils into fertile soils in China

"The soils are transformed and the yield is raised," said Yang Jingsong, a researcher at the Institute of Soil Science of the Chinese Academy of Sciences.

After a year of soil remediation, Yang made measurements on the pH value of the transformed saline-alkali soils and weighed the rice in an experimental field in Zhaoyuan County, northeast China's Heilongjiang Province.

The result is surprising. The yield of the variety 'Dongdao 122' and 'Tongze 861' is over 400 kilograms per mu, whereas the other piece of land without modification only yields 3.02 kilograms per mu.

To improve the soil, multiple methods have been used since September 2023, such as using phosphogypsum and microbial fertilizer.

What is the difference between the yield of rice per mu in saline-alkali land and normal land?

The paddy rice growing area of Wuchang City is regarded as Heilongjiang's premier area for growing high-quality rice. The yield of the famous rice variety "Daohuaxiang" is around 500 kilograms per mu this year, the Economic Information Daily reported.

Soil salinization and alkalinization are major problems for agriculture worldwide. The physical and chemical properties of such soil can prominently inhibit the crop growth and even lead to the death of crops, seriously affecting its yield.

China is the third most affected nation by saline-alkali soils on the planet. It has about 1.5 billion mu (100 million hectares) of saline-alkali land, of which about 550 million mu (33 million hectares) are available for utilization. 

According to Ai Zhiyong, deputy director of the National Center of Technology Innovation for Saline-alkali Tolerant Rice, this land is a potential resource for further safeguarding the country's food security.

Healthy soils are the basis for healthy food production.

Over the years, China has persistently promoted the comprehensive treatment and utilization of saline-alkali land. With the application of science and technology to treating the soil and developing new crop varieties, this land is being transformed into a "new granary" for the nation.

The country has developed more than 40 practical technologies in eight major systems, including salt removal technology and microbial approaches for soil desalination. In terms of crop varieties, China has promoted over 50 varieties of salt-tolerant crops.

In Zhenlai County of Jilin, researchers of the provincial Academy of Agricultural Sciences have successfully transformed the saline-alkali soil in a demonstration field using new modifiers, such as citric acid and pH decreaser. With the new variety "Jigeng 129," the total harvest of the rice reached 548.6 kilograms.

"It is extremely challenging to complete the construction and improve planting of 10,000 mu of land in such heavily saline-alkali soil within a short period of time, and to achieve a yield of over 400 kilograms per mu in the first year. However, our scheme achieved a yield of 548 kilograms per mu, which is a remarkable achievement," said Hou Ligang, director of the Rice Research Institute at the Jilin Academy of Agricultural Sciences.