China's production of plastic products in 2015 reached 75.6 million tons, the amount of waste was between 30 million and 40 million tons, and even more, the amount of recycling was 18 million tons. This means that about 20 million tons of waste plastics are buried and burned every year. , or even discard it at will. After landfill or dumping of plastic waste, the land will basically lose its use value. Incineration may bring more problems.
Such a large amount of plastic is used, of which agricultural plastics are one of the most important ones.
Agricultural plastics main application areas
Agricultural plastics are mainly divided into agricultural covering materials according to the application fields; agricultural water pipelines and water-saving equipment; agricultural plastic packaging materials and various materials for planting, breeding and storage. Agricultural film is the most important component of China's plastics industry, Important production materials in the development of modern agriculture, the application of this technology has led to significant improvements in China's agricultural productivity and changes in production methods.
Since the production of agricultural plastic film, the country has achieved two world firsts, namely, the production output and the first coverage area, which is roughly 1.6 times the sum of the rest of the world. According to incomplete statistics, the whole industry has agricultural film production enterprises. Nearly 1,000, the production capacity is more than 2 million tons, of which about 60 are enterprises with an annual production capacity of over 10,000 tons, and about 30 are large-scale backbone enterprises. Their production capacity and annual output account for 60% of the national total. The volume has reached 700,000 tons, covering an area of 50 million mu; the annual sales volume of plastic film is about 450,000 tons, covering an area of more than 220 million mu; the actual consumption of agricultural film has exceeded 1.2 million tons.
However, the technology of agricultural film now makes farmers 'love and hate'. With the popularization and application of plastic film covering technology, the problem of residual film pollution is becoming more and more serious, threatening agricultural production and ecological environment.
At present, the national agricultural film recovery rate is less than 2/3. In 2016, the agricultural environmental protection department's monitoring results in some areas of Gansu showed that all monitoring plots have different levels of discarded plastic film, with a residual amount of 5-14 per mu. 1. The pollution hazard is quite serious.
What should we do for the agricultural film problem?
It is recommended that one membrane be used for two years or one membrane for many years. Different membrane methods have an effect on the amount of film used. The amount of film used for full-film double furrow irrigation is 19.00 kg/hm2 more than that of full-film tiling. Different film mulching methods affect the amount of film used, and different film mulching methods have little or no effect on crop yield (P<0.05), but have an effect on the residue of mulch film in soil. It is recommended to use mulch film ≥0.008 mm.
Comparative analysis of the film-retaining method of the whole film double furrow irrigation film and the whole film mulching film showed that the former film mulch was larger than the latter, which increased by 21%. The film mulch film of the full film double furrow irrigation was The residual coefficient in the soil is 0.54, and the residual coefficient of the whole film tiling is 4.03. The residual amount of the agricultural film in the soil in the full-film double furrow irrigation film is smaller than that in the whole film, and the agricultural film in the soil. The residual amount should be small, indicating that the residual amount of the film is affected by the film coating method. It is recommended to use the full-film double furrow irrigation film.
The yield of corn after mulching was significantly increased (P<0.05), but the yield of two maize cultivars with different thickness of agricultural film was not significant (P<0.05), indicating that different film thickness had little or no effect on corn yield. Impact; the thickness of the film has an effect on the residual of the film in the soil. The thickness of the agricultural film with a thickness of 0.010 mm is smaller than that of the agricultural film with a thickness of 0.008 mm. It is recommended to use a film with a thickness of ≥0.008 mm and Degradation of agricultural film.