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Video: Greenhouse Film - Make The Right Choice. Grades, Thickness, Color Of Greenhouse Film. Where Can One Buy
It is known that the rate of photosynthesis, i.e., the decomposition of carbon dioxide by a green leaf, significantly depends on the wavelength of light falling on it. The highest rates are achieved when green leaves are irradiated with orange-red light.
In addition, if a small amount of light of a certain wavelength is "mixed" with the main light on which the plant is grown, then the degree of utilization of the entire light flux increases, which manifests itself in the enhancement of all vital processes of the plant, including an increase in the rate of photosynthesis. This phenomenon is called the "amplification effect" or "Emerson effect".
Numerous studies have shown that it is not the quantity of light, but its quality (wavelength) that accelerates photochemical reactions.
These facts could not fail to attract attention, and experiments on using the "Emerson effect" to increase crop yields were carried out in many countries. The result of such studies was the creation of special light-converting materials of the "Polisvetan" type, the use of which in the practice of growing vegetables, berries, flowers, woody crops, for forcing seedlings, etc. in greenhouse conditions increases economic productivity by 20-60% compared to plants grown in structures covered with materials that do not have a light-converting effect.
This effect is achieved by the introduction of special additives into the polyethylene film, which allow converting the part of the ultraviolet radiation of the solar spectrum that is useless for plants into the radiation of red light necessary for their vital activity.
Among the most famous Russian developments are such brands as "Redlight", "Urozhay", "Polisvetan" and "Antiplesen"
These films are a new generation of polyethylene films with unique Light-converting properties, which received the highest award at the International Exhibition "Eureka-96" in Brussels. The effectiveness of polysvetan films is confirmed by tests of the following institutions:
- State Agrarian University of the Russian Federation
- The Russian Academy of Sciences
- Central Scientific Research Institute
- Ministry of Agroindustrial Complex of Ukraine
- Ministry of Agriculture and Food of the Russian Federation
(Click to enlarge)
What else should you pay attention to when choosing a film?
Inexperienced summer residents think that the thicker the film, the longer it will last. Nothing like this. Plain polyethylene with a thickness and even 200 microns will crack and tear within 4-5 months if it is not stabilized. It is the presence of light stabilizing elements for the greenhouse film that is most important. As you know, ultraviolet light quickly destroys the film, in the end it simply breaks up into small pieces. This process is inevitable, but it can be significantly slowed down. This is what light stabilizers do. By the way, for stationary greenhouses, an elastic film with a thickness of 120-150 microns is optimal, for greenhouses on arcs, 80-100 microns can be used.
A separate note about reinforced film. This film is good for everyone - it is really strong and reliable, but … it is completely unsuitable for the greenhouse industry. Due to its relief, it gathers dust much faster, becomes cloudy and, ultimately, practically ceases to transmit light.
And yet - regardless of the appearance of the film, experts recommend changing it in the greenhouse at least once every three years, since the film becomes cloudy over time and its light transmission deteriorates, which negatively affects the yield and quality of agricultural crops. If it is well preserved, then it is better to use it for other household needs.
Films are tinted with food coloring only to distinguish them when sold. The color does not carry any other functional load. The dye then simply burns out in the sun, and the film becomes transparent. And persistent coloring, on the contrary, degrades the quality of the film, which would allow less color to pass through. In general, for greenhouses, the most ideal option is a glass or polycarbonate coating (flexible, transparent plastic). But the film is much cheaper, which, among other things, reduces the likelihood that your greenhouse will simply be "stripped" …
Beware of counterfeits
No one can determine by eye whether the product is light-stabilized or not, and the only guarantee in such a situation can be knowledge of trusted stores where you have never been deceived, or buying material directly from the manufacturer.
One of the oldest manufacturers of light-stabilized films of the brands "Redlight", "Antiplesen", "Urozhay" and "Polisvetan" in St. Petersburg is the production and commercial company "ORA", which has been operating in the market of plastic packaging for over 15 years and is a member of the St. Petersburg Trade Industrial Chamber.
For 7 years the company "ORA" has been a permanent participant of the World Fair "Russian Farmer", where it was repeatedly awarded with diplomas of the Fair, incl. in 2001 she was awarded a diploma "For the development of new technologies."
To date, the production site of the "OPA" company consists of high-quality newest domestic and imported (Austria, Taiwan) equipment:
- 6 extruders for the production of high and low pressure polyethylene films of various parameters;
- workshop for the production of plastic bags of almost any size;
- production waste processing line.
Films of the brands "Redlight", "Antiplants", "Urozhay" and "Polisvetan" can be purchased at the address:
St. Petersburg, VO, 15 line, 72, office 22, JSC "ORA", Tel.: (812) 327-99-66, Tel./fax: (812) 321-78-96
www.oraspb.spb.ru E-mail: [email protected]
Or directly from the warehouse (see diagram travel)