The environmental quality of land in China is generally good.

A few days ago, the China Geological Survey released the Report on Geochemical Survey of Cultivated Land in China (2015). The report shows that the environmental quality of the land within the survey scope is generally good. Of the 1.386 billion mu of cultivated land surveyed (accounting for 68% of the total cultivated area of the country), more than 1.272 billion mu of cultivated land is free of heavy metal pollution, accounting for 91.8% of the total cultivated area surveyed.

According to the report, by 2014, China had completed a total of 1.507 million square kilometers of land geochemical survey area, including 1.386 billion mu of cultivated land survey. The 1.272 billion mu of pollution-free cultivated land is mainly distributed in Jiangsu, Zhejiang and Shanghai regions, northeast regions, Beijing-Tianjin-Hebei and Shandong regions, northwest regions, Jinyu regions and Qinghai-Tibet regions, among which the pollution-free cultivated land area in Beijing-Tianjin-Hebei and Shandong regions and Jinyu regions accounts for more than 99% of the total surveyed cultivated land area in the region. In addition, 52.44 million mu of green selenium-rich cultivated land resources have been newly discovered in this survey, mainly distributed in Fujian, Guangdong and Qiong District, Southwest District, Hunan, Hubei, Anhui and Jiangxi District, Jiangsu, Zhejiang and Shanghai District, Jinyu District and Northwest District.

The survey results also show that in the surveyed areas, there are 34.88 million mu of cultivated land with medium to heavy metal pollution or exceeding the standard, and 78.99 million mu of cultivated land with light to light pollution or exceeding the standard. The high geological background, secondary enrichment in soil forming process and human activities are the main reasons for cultivated land pollution or exceeding the standard.

The report suggests that geological survey results should be given full play in land resources management, modern agricultural development and ecological environment improvement. For cultivated land that is currently free of pollution, it is necessary to actively prevent and control possible pollution effects caused by industrial and agricultural production activities on cultivated land. Selenium-rich cultivated land should be strictly protected and scientifically utilized, and dynamic monitoring and management of quantity and quality should be strengthened. It is suggested that remediation, adjustment of planting structure or land use, cause analysis and ecological risk assessment should be carried out for medium-heavy metal pollution or over-standard cultivated land according to different situations. As for the change of organic matter and pH value of land, active measures should be taken to reduce the exploitation and utilization of groundwater in cultivated land in northern China, strengthen the investigation and remediation of soil erosion, control industrial and agricultural production activities that may form pollution sources and reduce the impact of human activities.