What do you think about the prevention and harm of mulch film?

1. The harm of residual agricultural film to the environment is mainly manifested in the following four aspects

1. Harm to the soil environment.

Soil infiltration is the movement of water into the deeper layers of the soil due to free gravity. Because the residual film fragments in the soil change or cut off the continuity of soil pores, the gravity water generates greater resistance when moving, and the gravity water moves downward slowly, so that the amount of water penetration decreases due to the increase in the amount of agricultural film residue, and the soil moisture content decline, weakening the ability of cultivated land to resist drought. It may even make it difficult for groundwater to infiltrate, causing serious consequences such as secondary soil salinization. In addition, residual film affects the physical properties of the soil and inhibits crop growth and development. The main components of agricultural film materials are polymer compounds. These polymers are difficult to decompose under natural conditions. If they remain in the ground for a long time, they will affect the air permeability of the soil, hinder the movement of soil water and fertilizer, and affect soil microbial activities and normal soil. Structure formation ultimately reduces soil fertility levels, affects the growth and development of crop root systems, and results in reduced crop yields.

2. Harm to crops.

Because the residual film affects and destroys the physical and chemical properties of the soil, it will inevitably cause difficulties in the growth and development of crop roots. Any soil with residual film will prevent the root system from colluding, affecting the normal absorption of water and nutrients; when fertilizing between crop plants, large pieces of residual film will separate fertilizers, affecting fertilizer efficiency, resulting in reduced yields. According to the Environmental Protection Department of the Corps, when seeds are sown on residual film, the seed rot rate is 6.92, the bud rot rate is 5.17, the number of lateral roots of cotton seedlings is 4.8 to 7.6 less than normal, the death of cotton seedlings in the 2 to 3 true leaf stage is 1.19, and the cotton seedlings in the cotyledonary stage are dead. The death rate is 3.08, and the budding period is delayed by 3 to 5 days. The plant height was reduced by 6.7cm to 12.9cm. Relevant survey data showed that the impact of residual film on corn yield reached a significant level. Land with 187.5kg of film residue per hectare produced 9,420kg of corn, which was 909kg less than the control field without film residue. The yield reduction rate is 8.8.

3. Impact on rural environmental landscape.

Due to the limitations of recycling residual film, as well as the incomplete treatment and recycling of residual film, the method is not suitable, and some of the cleaned residual film is discarded on the edges of fields and fields. After strong winds blow, the residual film is blown to In front of and behind homes, in fields, and on treetops, it affects the rural environment and landscape, causing "visual pollution."

4. Harm to livestock.

The remaining film outcroppings on the ground are collected together with the pasture. When cattle and sheep accidentally eat the remaining film, it blocks the esophagus, affects digestion, and even causes death.

In short, from the harm caused by mulching film pollution to the environment and crop yields, it can be seen that the amount of residual mulching film in film-covered farmland is mostly close to or reaching the critical value that can reduce crop yields. Therefore, preventing and controlling plastic film pollution has become a very urgent and important task.

2. Some suggestions for preventing and controlling agricultural film pollution

To prevent and control plastic film pollution, we should follow the principle of "taking publicity and education as the guide, strengthening management as the core, and recycling as the main means. Based on the principle of "using alternative products as supplementary measures", we actively prevent and control residual film pollution, mainly through cleaning and recycling to reduce pollution, and rely on economic policies that are conducive to recycling to increase recycling rates.

1. Strengthen publicity and education.

Preventing and controlling plastic film pollution is a systematic project that requires the joint efforts, support and participation of all departments, industries and the broad masses of farmers. It is necessary to vigorously carry out publicity and education to raise the awareness of leaders at all levels and farmers about the long-term and serious harm of mulch film pollution and the difficulty of recovery, and to increase the consciousness of recycling mulch film.

2. Accelerate the formulation of economic policies for recycling residual film.

It is necessary to formulate some preferential policies to encourage the development of enterprises that recycle, process, and utilize waste mulch films, and to mobilize their enthusiasm. In order not to increase the burden on the government, and at the same time reflect the principle of "who pollutes, who controls", Mulch sales departments and mulch consumers should be required to recycle on their own. Enterprises or individuals that cannot recycle by themselves must pay recycling processing fees to compensate recyclers.

3. It is recommended to establish standards for residual film residues.

It is necessary to formulate necessary standards for residual film residue in farmland and charging standards for excessive residual film residue, so that farmland film pollution can be brought into the legal management track as soon as possible.

4. Vigorously promote the technology of film removal at the right time.

The so-called film-uncovering technology at the right time refers to changing the film-uncovering after crop harvest to before-harvest, and selecting the best film-uncovering period for crops. The best time to remove the film is when it clears up after a rain or when the soil is moist in the morning. The mulch cotton should be removed before the head water.

Properly peeling off the film has the following advantages: First, the technology of properly peeling off the film can shorten the covering time by 60 to 90 days, so the film still maintains good toughness and is easy to recycle, with a general recovery rate Reach above 95. Basically eliminate the residual film pollution of farmland soil and protect the farmland ecological environment. Second, the technology of removing the film at the right time can reduce the humidity in the field, which is beneficial to suppressing crop diseases and reducing corn sheath blight. Third, the technology of film removal at the appropriate time is beneficial to the development of crop root systems and enhances soil permeability. Fourth, film removal at the right time is usually done before or during the reproductive growth period of the crop. At this time, the crop needs a lot of water. At this time, film removal is conducive to the direct reception of water by the roots, which is beneficial to the growth of the crop. Fifth, removing the film at the appropriate time is beneficial to field management in the later stages of crops, facilitating cultivating and weeding, and facilitating top dressing of mid- and late-stage crops and cultivating soil to prevent lodging.

In short, the technology of removing mulch at the right time can not only increase the recycling rate of mulch film, save the labor of recycling mulch film, but also increase crop production. Therefore, it is necessary to vigorously promote the technology of film removal at the right time to promote the development of agricultural production.

5. Take measures that combine manual and mechanical recycling to increase the recovery of residual mulch film.

In addition to the measures of removing the film before watering, manpower and labor can also be organized to recycle the residual mulch film manually or with a rake. A mulch film recycling machine can be used to recycle the land before plowing, leveling, sowing and after harvesting. Get better results. For example, the ISQ-20 mulch film removal machine developed by the Liaoning Provincial Agricultural Mechanization Research Institute and the circular rolling nail-type residual film removal machine developed by Maigaiti County in Xinjiang have achieved good results in their promotion and use.

6. Increase the toughness of the mulch film to facilitate the recovery of residual film.

At present, agricultural mulch films commonly used in rural areas are ultra-thin films with a thickness of 0.007cm, which are easily broken and difficult to recycle. The mulch film used in some foreign and mainland provinces and cities is relatively thick. The thickness of the mulch film used in brother provinces and regions is 0.015cm. It is not easy to break and is therefore easy to recycle. It is recommended to increase the thickness of the mulch film to enhance the toughness of the mulch film and facilitate the recovery of residual film.

7. Research and develop new materials and find alternatives to agricultural film.

Practice has proven that only by developing new materials that are easily degradable and pollution-free can we eradicate mulch pollution. The mulch films currently used are all polyethylene agricultural films, which are chemically stable and difficult to decompose and degrade, thus causing pollution to the soil environment. Therefore, the development of pollution-free and degradable biofilms should be encouraged to replace polyethylene agricultural films. At present, bio-agricultural films are difficult to promote due to insufficient strength or high cost. The performance of bio-agricultural films should be further improved and optimized, and the cost should be gradually reduced to facilitate promotion and application.

8. Optimize the farming system.

Further strengthen the stubble rotation system, and reduce the average coverage rate of mulch film per unit area through stubble rotation of grain, cotton, vegetable and cotton, thereby reducing the hazards of residual film pollution.

Using plastic film covering cultivation technology can achieve the purpose of increasing temperature and moisture and increasing yield and harvest. At the same time, the residual film left in the soil also pollutes the cultivated land. If this continues, the physical properties of the soil will deteriorate, fertility levels will decline, crop root growth will be difficult, and seedling development will be retarded, resulting in reduced yields. What is even more serious is that long-term accumulation of residual film may completely destroy the production potential of land resources, turning large areas of fertile farmland into barren desert land with no grass growing on it. Therefore, controlling mulch pollution and protecting the ecological environment of farmland are the keys to the sustainable development of mulch planting. At present, when degradable and non-polluting mulch films have not yet been widely promoted and applied, film removal technology at the appropriate time is an effective measure to prevent and control residual film pollution. This technology increases the recovery rate, prevents mulching film pollution, and protects the fertility of cultivated land. Therefore, it is necessary to strengthen publicity and education, improve the environmental awareness of leaders at all levels and farmers, vigorously promote mulching film pollution prevention and control technologies such as timely removal of mulching films, and reduce the amount of residual film. To ensure sustained and abundant agricultural harvests, Baneda Bika fertilizer is used to improve the soil and increase soil organic matter.