There is an urgent need for "laws to follow" for the prevention and control of soil pollution.

New progress has been made in soil legislation, which has attracted much attention from the outside world. Recently, the Ecological Department of the Ministry of Environmental Protection held a forum for soil remediation enterprises to solicit opinions for the drafting of the soil environmental protection law. The relevant person in charge of the Ecology Department of the Ministry of Environmental Protection said that the next step will be to strengthen field research on soil legislation, actively improve the draft law, and promote soil legislation in an orderly manner.

There is an urgent need for "laws to follow" for the prevention and control of soil pollution.

Land, which contains all things and gives birth to life, is known as the mother of human beings. However, in recent years, with the rapid development of industrialization in China, the earth has been constantly harmed by all kinds of pollution. Just because of insufficient prevention and control of soil pollution and weak environmental supervision, food and drug safety incidents occur frequently. Since 2008, more than 100 major pollution accidents have occurred in the country. At present, the current situation of land pollution in China is grim, and the causes are very complex, resulting in a choking "death of the earth".

According to industry insiders, soil pollution refers to the phenomenon that substances with physiological toxicity or excessive plant nutrient elements enter the soil, resulting in the deterioration of soil properties and the imbalance of plant physiological functions. In addition, soil pollution can lead to changes in soil composition, structure and function, thus affecting the normal growth and development of plants, causing harmful substances to accumulate in plants, endangering human and animal health through the food chain, or through surface runoff and soil wind erosion. to transfer pollutants to other places. Soil has a certain ability of self-purification, but once the soil is polluted, it is difficult to recover, especially heavy metal pollution.

Heavy metal pollution of cultivated land 1x6 in China

From the incident of excessive cadmium rice in Hunan, people know that a large number of cultivated land in Hunan has long been polluted by heavy metals.

In recent years, there has been a lot of news about heavy metal pollution in cultivated land. Zhang Weili, vice president of the soil Society of China, who has been concerned about the problem of soil pollution in China for a long time, has said that at present, soil pollution in China is becoming more and more serious, and the situation of prevention and control is very serious.

According to media reports, 300 million mu of arable land across the country is threatened by heavy metal pollution, accounting for 6% of the total farmland in the country. According to documents of the Ministry of Environmental Protection, during the sampling and monitoring of harmful heavy metals in 300000 hectares of basic farmland protected areas in China, it was found that 36000 hectares of soil heavy metals exceeded the standard, with an over-standard rate of 12.1%. Statistics from the Ministry of Land and Resources show that at present, more than 10% of the cultivated land in the country has been polluted by heavy metals.

At the same time, cultivated land is seriously affected by heavy metal pollution. Chen Shibao, a researcher at the Institute of Resources and regionalization of the Chinese Academy of Agricultural Sciences, said that the direct consequence of heavy metal pollution is a decline in the quality of cultivated land, resulting in a decline in the quality and quality of agricultural products and export restrictions. at the same time, it brings potential harm to human health.

According to statistics from the environmental protection department, the annual grain pollution caused by heavy metals is as high as 12 million tons, causing direct economic losses of more than 20 billion yuan.

"at present, the soil pollution in China is more serious than that in other countries, and the increasing trend of pollution may continue for another 30 years." Pan Genxing, a professor at Nanjing Agricultural University and an expert in Chinese soil science, once made such an assertion. He said that not only is the pollution getting worse, but it is also spreading.

Where does pollution come from?

High human activities and natural background values such as industry, mining and agricultural production are the main reasons for soil pollution or exceeding the standard.

The waste gas, waste water and waste residue discharged from the production and management activities of industrial and mining enterprises are the main "killers" of the soil. Among them, all kinds of solid wastes such as tailings and hazardous wastes are piled up, resulting in soil pollution around them. Among the 1672 soil sites investigated in 70 mining areas, the over-standard sites accounted for 33.4%. In addition, automobile exhaust emissions lead to lead, zinc and other heavy metals and polycyclic aromatic hydrocarbons (PAHs) pollution in soils on both sides of traffic trunk lines. Among the 1578 soil sites surveyed on both sides of 267trunk highways, 20.3% of them exceeded the standard, which are generally concentrated within 150m on both sides of the highway.

In addition, agricultural production activities are an important cause of soil pollution in cultivated land. Sewage irrigation, unreasonable use of agricultural inputs such as chemical fertilizers, pesticides and agricultural film, as well as livestock and poultry breeding, lead to soil pollution of cultivated land. The survey results show that compared with woodland, grassland and unused land, the over-standard rate of cultivated land is the highest, reaching 19.4%, of which the proportion of mild, mild, moderate and severe pollution is 13.7%, 2.8%, 1.8% and 1.1%, respectively. The main pollutants are cadmium, nickel, copper, arsenic, mercury, lead, DDT and polycyclic aromatic hydrocarbons. In addition, the high natural background value is the reason for the excessive heavy metals in some regions and watersheds.