China's third national soil survey has made significant progress upon the completion of field sampling tasks, the Ministry of Agriculture and Rural Affairs said Thursday.

As of the end of November, 88 percent of laboratory testing for the collected samples has been finalized, ministry official Yang Peng told a press conference.

Over 400,000 survey workers from more than 30,000 institutions collected data from more than 2.87 million sample points across 2,860 counties, the official noted, adding that a total of 3.11 million soil samples were obtained, marking the successful completion of field investigations.

Launched in 2022, the four-year project aims to conduct a comprehensive analysis of soils across farmlands, gardens, woodlands and grasslands associated with agricultural production, as well as unused land that can be repurposed. The survey focuses on the conditions, types, quality, utilization, and potential of soil.

Rapid economic and social development has significantly altered China's soil resources since the second national soil survey was conducted from 1979 to 1984, Yang said, noting that it is essential to reassess the current status of the nation's soil.

The findings could serve as a foundation for optimizing soil use, improvement and protection while supporting policy decisions in economic, social and ecological fields, he added.

The ministry said it aims to complete data auditing, compilation of the findings and result sharing of the survey by 2025.