Soil pollution is becoming increasingly prominent, and pollution prevention and control brook no delay

Editor's Note In recent years, the problem of soil pollution in China has become increasingly prominent, and food safety incidents caused by it have occurred from time to time, making soil pollution prevention and control brook no delay. Some readers said in letters that for soil pollution treatment, source control is the key, and at the same time related laws and regulations should be improved and perfected as soon as possible, soil treatment technologies should be popularized, and the soil should be made clean again to ensure food security.

Let soil pollution treatment have laws to rely on

⟦NL> Having long served as a grassroots agricultural technology extension worker, the author has witnessed during long-term work how chemical fertilizers, pesticides and agricultural films, while helping the vast number of farmers increase production and income, have also brought pollution to the soil. Taking chemical fertilizers as an example, long-term heavy use of chemical fertilizers can cause soil compaction, reduce the number and activity of soil microorganisms, and lead to soil acidification.

In response to the increasingly serious problem of farmland soil pollution, first, laws and regulations related to soil protection should be issued as soon as possible. At present, China's current soil environmental quality standards are incomplete, and some aspects are still blank. It is suggested that the “Soil Pollution Prevention and Control Law” be issued as soon as possible, and that soil pollution standards, remediation standards, and safety standards for agricultural products and feed be revised and improved, so as to achieve law-based prevention and control, law-based supervision and law-based management of soil pollution.

Second, farmers should be guided to apply fertilizer and pesticides scientifically. Through publicity and education, farmers should be strongly encouraged to use efficient and environmentally friendly agricultural inputs, and comprehensive subsidies for agricultural inputs should be increased, actively guiding the vast number of farmers to apply fertilizer and pesticides scientifically and rationally, and vigorously promoting the development of ecological agriculture and the agricultural circular economy.

Third, the treatment and remediation of polluted soil should be advanced. Testing of soil conditions should be continuously strengthened, combining general testing with key monitoring and implementing routine testing. Soil environmental conditions should be understood in a timely manner, a soil environmental quality investigation and monitoring system should be established, and a soil environmental quality monitoring network should be built. Related policies, laws and standards for soil monitoring and treatment and remediation should be improved, and all soil protection policies should be truly put into effect, accelerating the formation of a soil environmental protection system and gradually improving soil environmental quality.

“White pollution” urgently needs treatment

Plastic agricultural mulch film technology plays an important role in increasing agricultural production, but as usage increases, residual agricultural film left in the fields affects the regenerative capacity of the soil and threatens and damages the agricultural production environment. Taking the Xinjiang Production and Construction Corps, where the author is located, as an example, in 2013 the area polluted by residual film in the Corps was about more than 10 million mu, accounting for more than 50% of the cultivated land area, and residual agricultural film has become a “white pollution source” for the soil that urgently needs treatment.

First, the recovery rate of residual film should be increased. By measures such as raising the recovery price of residual film and carrying out activities such as trading old agricultural film for new, farmers' enthusiasm for clearing residual mulch film from farmland can be mobilized. Through publicity and education, farmers should gradually be guided and trained to be consciously aware of their role as the main body in waste film recovery, and to develop the good habit of clearing residual film by hand whenever they go into the fields.

Second, a recovery mechanism for residual agricultural film should be established. Preferential policies should be formulated, subsidies for large residual film recovery machines should be increased, and residual film recovery agricultural machinery cooperatives should be established to speed up residual film recovery work. Mulch film thicker than 0.01 mm should be actively promoted, and government subsidies can be used to offset the added costs incurred by land producers. Investment should be increased, and through the establishment of an industry reward mechanism, the recovery of residual film and the promotion and use of new biodegradable mulch film should be promoted, and support should be given to the research, development and promotion of technologies for recycling and utilizing waste agricultural film.

Finally, policies and regulations concerning standards for residual agricultural film in soil should be formulated as soon as possible. The comprehensive treatment goals, assessment methods, and reward and punishment methods for residual film in farmland should be improved, the service scope for recycling and reusing waste mulch film should be expanded, and the enthusiasm of the government, farmers, enterprises and society to jointly participate in the resource utilization of mulch film should be increased, so that the prevention and control of residual film pollution is placed on a law-based track.

Mobilize farmers' enthusiasm for treatment

Farmers are the cultivators of the land and also the main participants in agricultural production. Therefore, to treat farmland soil pollution, the key is to raise the environmental awareness of the vast number of farmers, mobilize their enthusiasm for treating soil pollution, and encourage farmers to truly shoulder the social responsibility of protecting the soil environment.

First, farmers should be encouraged to apply more organic fertilizer, increase the content of soil organic matter, and enhance the adsorption capacity of soil colloids for heavy metals and pesticides. Applying more organic fertilizer can not only reduce pollution of the soil, but also effectively eliminate diseases, pests and weeds, and give play to the positive efficacy of pesticides. Pesticides and chemical fertilizers should be applied scientifically, and the amount and scope of use of chemical pesticides should be controlled. Biological techniques should be adopted to control crop diseases and insect pests, avoiding the use of highly toxic and high-residue pesticides.

Second, farmers' cultivation patterns should be changed, changes in soil environmental conditions should be promoted, and the harm of certain pollutants should be eliminated. According to the types of soil pollutants, plants with relatively strong absorption capacity can be grown to reduce the content of toxic substances, or the soil can be purified through biodegradation, or measures such as soil replacement and deep plowing can be taken to change the direction of migration and transformation of pollutants in the soil and reduce absorption by crops. Non-food crops should be grown on polluted soil to reduce the entry of pollutants into the food chain.

Third, a promotion mechanism combining soil planting and nurturing should be built. The short-sighted behavior of some farmers who “plant without nurturing” and “value planting over nurturing” should be changed, a soil condition ledger for agricultural land should be established, and a soil physical examination system for contracted fields and transferred agricultural land should be implemented. A soil maintenance subsidy system can be established, incorporating the application of farmyard manure and organic fertilizer into the scope of subsidies, encouraging farming households to accumulate more farmyard manure and apply more farmyard manure, so as to ensure soil health.