Since the 1980s, modern plastic cover materials such as plastic film, shade nets, and insect-proof nets in China, such as seedling trays, seedling trays, and rice-based seedlings, as well as plastic water-saving irrigation equipment, have become increasingly popular in agricultural production. The more extensive.
Utilizing increasingly developed modern science and technology, vigorously develop and promote agricultural plastics application technologies. For the prevention and reduction of disasters, tapping the internal potential of agriculture, and building efficient, high-quality, high-yield agriculture, all have a sustainable, rapid and healthy development of the national economy in China. Very important significance.
I. Agricultural Plastics Covering Materials 1. Shed Membrane Covering cultivation techniques in China have been applied since the late 1950s. At first, it was a small plastic shed. In 1969, plastic sheds appeared. In the 1980s, the shed film began to replace glass in large areas and was used as a transparent covering material for greenhouses. According to incomplete statistics, from 1985 to 1986, the total area of ​​horticultural facilities in the country was 68,000 hectares (ha), which was 699,100 hm2 in 1995-1996 and more than 1.6 million hectares in 1999-2000. The annual use of various films across the country is about 1.5 million tons, and the annual update demand is about 700,000 tons.
(1). Solar greenhouses The total area of ​​existing solar greenhouses in China is more than 400,000 hm2, of which about 240,000 hm2 are in high-efficiency and energy-saving solar greenhouses. Most of the greenhouses in winter production use PVC non-drop film or PE multi-functional composite film; in spring and autumn production, in order to reduce the covering cost, PE common film is often used. In recent years, the newly developed EVA multi-functional composite film has significantly better comprehensive performance than PVC non-drop film and PE multi-functional composite film, and is a key agricultural functional film to be developed in the future.
(2). Plastic middle and large sheds At present, China's plastic large and medium-sized sheds have an area of ​​about 540,000 hm2, with a wide distribution area, mostly in the middle and lower reaches of the Yangtze River and in Huanghuai area. In the past, they mainly used common shed membranes. Since the late 1980s, large-area plastics have been converted to PE. Multifunctional film. In recent years, low-VA content EVA multi-functional composite films have also begun to be used in plastic large and medium-sized sheds, and have shown broad application prospects.
(3). Plastic small arches Plastic small arches are widely distributed in China, with various structural forms. They are the fastest growing and the largest area of ​​simple facilities in gardening facilities, and now exceed 700,000 hm2. The transparent cover material of the small arch shed is mainly made of ordinary PE and PVC film. In recent years, the low VA content of EVA heat-insulating film is very popular as a small arch cover material.
In addition to the above-mentioned horticultural facilities, there are about 500 hm2 modern multi-span greenhouses in China, most of which were imported from abroad in recent years. Many plastic films are used as transparent covering materials.
2. Shading nets China's traditional shading, cooling, and anti-rainstorm covering materials are reed curtains; in the early 1980s, they began to introduce foreign modern sunshade cooling covering materials - shading nets; in the mid to late 1980s, domestically developed high-strength, anti-aging Shade net, and enter the production test phase, the 1990s entered the promotion stage. At present, the annual usage of shade nets nationwide has reached more than 200 million m2, covering an area of ​​nearly 80,000 hm2, which is mainly used for the cultivation of vegetables, flowers, tea, fruit trees and seedlings in the south. The annual demand for shade nets is 60 million m2, which is about 3500 tons.
3. Insect nets In recent years, in order to satisfy the consumers' demand for high-nutrition, non-pollution and health-care vegetables, the southern part of China began to use insect nets to completely close the cultivation of vegetables to effectively prevent pest damage and spread by pests or infection by wounds. The occurrence and spread of a variety of diseases, so as to achieve the basic production of pesticides, to provide consumers with ease food. China Defense wormnet has now demonstrated and promoted more than 4 million m2, covering more than 1,500 hm2 of cultivated area.
4, plastic film China from the late 60s of the 20th century, the use of waste shed film for ground cover test, and achieved good temperature, security and early maturing results. In 1979, a special film production technology and covering cultivation technology was introduced formally from Japan. It has been expanded to 12 million hm2 and the annual demand for plastic film is about 450,000 tons. The coverage cost is very low, but it is very difficult to manually remove the waste film.
5. Forage Grass Membrane Since the 1980s, China has vigorously promoted ammoniated forages. At present, the total amount of crop straws in the country is about 500 million tons each year, and 30% of them are treated with ammonia as forage grass. The special resin for ammoniated membranes has been listed as a special item, with an annual target of 160,000 tons.
6, agricultural non-woven fabrics and shade net, China's non-woven production test demonstration also began in the late 80s, but due to various reasons, the development is slow, the application area is about 5000hm2, the annual consumption is about 1250t, The annual demand is about 500t.
It is estimated that by 2010, the cultivated area of ​​China's horticultural facilities may increase to about 2 million hm2. The proportion of functional agricultural film in the total annual production and sales volume of greenhouse films will increase from the current 22.9% to more than 40%, and the greenhouse film will be in the northern solar greenhouse. The application of horticultural facilities will be significantly accelerated: the cultivated area covered by mulching film is expected to reach 14 million hm2; the application area of ​​sunshade nets, insect nets, forage grass films and reflective films will also increase significantly. It is worth mentioning that the area suitable for the promotion of plastic film coverage in China is about 37 million hm2. At present, only over 9.6 million hm2 has been promoted. The popularization rate is less than 26%, and the promotion potential is great. It is estimated that by 2010, the cultivation area of ​​mulching film in China is expected to reach 17 million hm2.
Second, water-saving irrigation equipment China's per capita possession of freshwater resources is only 2300m3, less than 1/4 of the world average, drought is the main threat to China's agricultural stability and sustainable development. To this end, the Chinese government began water-saving irrigation project construction since the 1970s. At present, the national water-saving irrigation project area has reached more than 15.3 million hm2, accounting for about 26% of the total irrigated area; the sprinkler irrigation area is more than 100 million hm2. The area of ​​water transported by low-pressure pipelines was more than 5.2 million hm2, and the area of ​​micro-irrigation (including drip irrigation, infiltration and micro-injection) was 1.46 million hm2. The plastic low-pressure pipeline can reduce the loss of water transmission by 60%-90% compared with the earth canal; the irrigation irrigation can save 30%-50% of the water compared with the traditional surface irrigation, and improve the land use efficiency by 5%-10%: the micro-irrigation can save 10% compared with the irrigation- 30%, energy consumption is reduced by about 30%. At present, the annual demand for plastic water-saving equipment in the country is around 1 million tons.
The promotion and application prospects of water-saving irrigation equipment are also very optimistic. It is estimated that by 2010, China's water-saving irrigation area is expected to reach 30 million hm2, of which more than 3 million hm2 will be sprayed and micro-irrigated, and more than 10 million hm2 will be added to the piped irrigation irrigated area, and the canal impermeable irrigated area will be about 7 million hm2.
Third, plastic nursery containers Plastic nursery containers include plastic cartridges floppy disk, plug, purlin and flower pots and so on. In the late 1980s, China began to develop plastic steroidal floppy disks, which are mainly used as seedling containers for rice seedlings. Currently, rice dumping area is more than 710 million hm2. In the early 1980s, China began to use plastic plugs and mulches instead of soil hoppers. In addition, since the 1990s, plastic flowerpots have begun to replace tile pots for ornamental flowers and trees. At present, the cultivation of seedlings and ornamental plants for the production of various crops cultivated in plastic plug trays, mulches, and flower pots requires about 300 million or about 30,000 tons per year.
In addition, plastic nets, plastic wraps, pesticides, edible fungi substitutes for cultivation of film tubes, foam plastic plates and Other plastic products, are also widely used in agriculture and animal husbandry production, agricultural products processing and aquaculture (fishing). It is estimated that by 2010, the area of ​​throwing rice in China will be 14 million hm2, and the area of ​​application of other nursery containers will also increase significantly.