Alexander Shagaev worked as the main agronomist at the greenhouse Seim Agro from the beginning of its construction. He was engaged in the selection of personnel, equipment and production technology. Alexander Yurievich shares information on how the microclimate is maintained in the greenhouse, which devices and systems regulate the main climatic indices in a closed ground.
The first thing you need to pay attention to when building a greenhouse is its position on the plane. If you are inside a greenhouse in the morning, when the sun is just rising, you should see it at the end of the row. If you do not go, the sun should go down at its end, and at noon in the ranks there must be a shadow. If you do not go, the sun should go down at its end, and at noon in the ranks there must be a shadow. If your greenhouse is turned 90 degrees and the sun pierces your array to the ground itself, this is the first reason your plants will die as a result of overheating of the root mat. Overheating of the mat leads to the emergence of fusariosis, pythium and other root diseases. Not properly built greenhouse leads to that the greenhouse will never work properly, but it is not possible to correct it in the future, therefore this factor is very important.
The climate control system consists of ventilation pane, ventilation system, screens, lighting, evaporation cooling and pre-humidification system, heating system, CO2 supply system. Screens are of two types: energy and shading. Fans to create an even temperature field in the greenhouse. There may be, maybe, not to be. Evaporation cooling and pre-humidification system helps maintain optimal moisture in plants and is used in case of moisture deficiency in the greenhouse. Also there should be sensors for monitoring temperature, humidity, pH - this is the main parameters in the greenhouse, they should always be monitored. In Russia 4 systems of contour heating are used (under gutter, tent, a pipe of growth, a pipe of a rail), in the Netherlands 2 systems are used, as they have different climate, in Africa there is only 1 heating system - a pipe of rails. Each of the systems has its influence on the greenhouse, on the microclimate and all other processes that occur in the greenhouse.
The agronomist operates climate computer for regulating humidity, temperature and moisture deficiency. However, setting all the parameters of this computer is not easy. Unfortunately, the Dutch exhibit only average figures. And to understand everything in a climate computer, you need to be a fan of this business. As a rule, now this is achieved on climate computers Priva. There are at least some recommendations for computers to make settings and not think about it. And on more complex Dutch computers there are no recommendations, because to write them, you need to spend years. The microclimate parameters that can be monitored are: air temperature in the greenhouse, plant temperature, humidity.
The main factor to which we aspire is moisture deficit. The first thing you need to hang over the operator's desk, which monitors the control system, is the moisture deficit table. To properly observe the amount of humidity in the greenhouse, each agronomist has a table for moisture mats in the form of a graph. If you are working correctly with the moisture deficit table, then only one of them is enough to control the plants. If you do not know how to manage plants, neither the correct temperature, nor the correct watering, nor the correct chemicals will help you. You must understand correctly what is happening in the greenhouse. Deficiency of humidity, as well as hunger in humans. The plant always seeks to ‘eat’, get additional assimilants, move them to the necessary zones: the root, the fruiting zone or the growth point. As soon as the moisture deficiency in our greenhouse ends, the plant stops, the flow of nutrients through the vessels stops and here the plant has a critical period when all diseases, such as fungi, viral and bacterial infections attack it. A healthy plant with a humidity deficit of 24 hours a day, basically not affected by disease and has no condensation on the leaves.
There are also installations for temperature control, which calculate its daily average. The most important, apart from a moisture deficit, is the monitoring of average daily temperatures in the greenhouse. In the summer, there may be overheating. To lead the culture in more hot conditions, it is necessary to strive to reduce the average daily temperature, based on data from temperature sensors.
The construction of a greenhouse must, first of all, evaluate all environmental impacts that are carried out on a given object. On the microclimate in the greenhouse are influenced by external factors such as: ambient temperature, humidity, the number and duration of sunlight and wind speed. These are the factors that are taken into account when programming greenhouse management. Modern greenhouses can be considered closed objects or semi-closed. As a rule, these are greenhouses of the 4th generation, there are already greenhouses in Russia and the 5th generation. The fourth generation is a semi-open model that includes a vent opening system, a heating system, humidification is usually evaporative cooling and pre-moisturizing system, which may or may not be present. Evaporative cooling system is of high pressure and medium pressure. Medium pressure is a waste of time and money, but it is a system that can render the greenhouse unusable for one day, if not properly used. For example, if you do not correctly bring water into the greenhouse, do not draw water from the greenhouse, respectively, you lose breath, photosynthesis, you lose the crop.
Greenhouses of the fifth generation are Ultra Clima. An example of such a greenhouse is LipetskAgro is a very beautiful greenhouse and they continue to be built. The same greenhouses are being built in Yelets, in the village of Sadovoye in Yekaterinburg. This is a completely closed greenhouse: there are no windows or very few windows, there is a pumping of cool air, plus lighting. The fifth generation is the most modern greenhouses in Russia, which exist and will now be three.
From the seminar of Alexander Yakovlevich Shagaev, an agronomist consultant with 15 years of experience in greenhouses.
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