1. Agricultural mulch
Plastic material plastic mulch, antifreeze, heat preservation of warming, adjust lighting, water saving, weeding, and control the effect of salinity, which promote crop precocious, improve crop quality and yield. Membrane varieties more, basically have normal color transparent film, plastic film, black film, white film, purple membrane, green film, blue film, red film, infrared film, turn light film, double color film, silver film, aluminum foil film, perforated film, the emergence of film, weeding film, thermal insulation membrane, membrane can drop solution and ageing resistance film, etc. Film has been applied in all kinds of crops and cash crops cultivation and covered the ground of the early rice seedlings.
(1) the characteristics and use of all kinds of plastic
1. The colorless transparent film good pervious to light, the film temperature is high, during the spring and autumn is suitable for use. It is due to the high temperature in the membrane, used in rice seedlings and thermophilic crops, such as eggplant, sweet pepper, watermelon is good, easy to cause disease for some crops. Defect is formed in the membrane droplets will affect the pervious to light, it was also known as plastic film.
2. Contain hydrophilic material, plastic film covering membrane water droplets on the inner surface after connection into membrane and the membrane of the water, so called dripping membrane. This film high light transmittance, film inside and outside temperature difference is big, good use effect than ordinary colorless transparent membrane, membrane humidity is also relatively small.
3. The colored film and infrared film, turn light film are collectively referred to as photosynthetic efficiency membrane. Photosynthetic efficiency through selective membrane through the wavelengths and the level, strong pertinence, has a different effect on different crops.
4. Black mulch can control weeds, but increase the ground temperature is less (only 2 ~ 3 degrees Celsius), suitable for Chinese cabbage, leafs Mu, mushroom, tea, tobacco, etc.
5. White plastic light reflection on crop leaves and fruit, can be beneficial to photosynthesis and ripening effect. Membrane blocking red orange green light and LanZiGuang, and can inhibit the growth of weeds and increase the production of certain crops, but few use by inhibiting weed ability is not strong, green membrane used in eggplant, strawberry, melon and other crops.
6. Double color film by reducing the pervious to light inhibit weeds and get the suitable temperature, used in tomato, strawberry, bell pepper and other crops.
7. The purple membrane can absorb through the red, blue and green light, good crop growth, such as for spinach, can improve the yield, extend the listing period. Blue membrane under the condition of weak light illumination, high light transmittance, low transmittance strong light conditions, so the good heat preservation, used for rice seedlings, vegetables, peanuts, cotton, strawberry, potato and other crops can improve the yield and quality.
8. Can through the red light and blue light, red membrane can promote the cucumber crop growth, etc. Add have infrared transparent infrared film additives, raising temperature range increased by 20%.
9. Membrane contains light conversion agent, converting the high-energy shortwave sunlight into low energy level long long wave spread, provide suitable lighting conditions for crops, promote crop growth and increase production, due to cost reasons, at present in our country to turn light film has not been used for mulch and only be used for films.
10. Silver film and aluminum foil membrane with strong light reflection, can drive the worm aphid, can improve the ground temperature, can supplement the shortage of the crops and fruit on the back of the illumination, and thus reduce the virus harm, increase crop yield, improve the fruit coloring and fruit sugar.
11. Silver film is suitable for cucumber, tomato, watermelon, celery, and leafs Mu, spinach, tobacco and other crops.
12. The aluminum foil membrane suitable for use in high temperature season vegetables, can also be applied to peach, apple, cherry fruit trees. Due to high cost of aluminum foil membrane using fewer at present.
13. According to the crop cultivation spaced arrangement on a porous membrane with a certain diameter of hole, diameter of 2 ~ l0mm. The experimental results show that different crops require different pore size and pore density. A porous membrane on the one hand can guarantee oxygen, the other party
Surface can promote radicle stretched out, and big hole can increase the moisture evaporation, reduce the temperature. Emergence of membrane by crop spaced out strip seam, agree with seeding location, after seedling unearthed from the seam drill out, suitable for garlic, rice cultivation.
14. Weeding film in addition to the black plastic, can be add herbicides in film or coating on the membrane surface, plays a role of weeding herbicide slow release into the soil, weeding film has been widely applied in sugar cane, corn planting, can also be used for planting peanuts, peppers, tomatoes but cannot be used on tobacco, cucumber cultivation, also cannot use hot day.
15. Biodegradable film results from the elimination of plastic debris in the soil cause "white pollution". Degradable mulch is biodegradable, photodegradation and light/biological double degradation type 3 kinds. Degradable mulch around now, have a certain number of application in the course of cultivation of various crops, but application is not widespread. Degradable mulch promoted the king to have two reasons for the difficulties in, one is the price, the second is around the existing technical level checks and soil, climate, light and other conditions lead to different membrane degradation time can't accurate control, the maturity and perfection of degradable mulching film technology is still need to experience a long time.
16. Thermal insulation membrane by reducing the amount of long wave infrared through and have heat preservation effect, is widely used and winter in the north.
In addition still can collect through water permeable membrane. Permeable membrane has two kinds, one kind is with certain pore density (punching) membrane of holes; Another is through selective microporous membrane. Microporous membrane can be caused by the pore or stretching to the hole, a hydrophilic microporous membrane, can waterproof but not through water vapor, microporous membrane using effect is better. Using permeable membrane can decrease The Times of crop irrigation water-saving effect.
