In order to prevent virus diseases, 60-mesh insect-proof nets are installed on the upper and lower air vents of the greenhouse, which can completely block the Bemisia tabaci and other pests outside the shed, and prevent the virus-transmitting pests from bringing viruses and other germs from outside the shed into the shed, reducing vegetables. incidence rate.
This also has a great impact on the ventilation and cooling of the greenhouse. Even if the sunshade net is used to cool down, the temperature in the greenhouse is still high because the air circulation in the greenhouse is not smooth, and the maximum temperature in the greenhouse is still maintained above 35 ℃. So, how should vegetable farmers cool down after installing 60-mesh insect-proof nets?
Open the upper and lower air vents of the greenhouse to the maximum. Now the straw curtain on the greenhouse has been removed, and the air vent on the top of the greenhouse can be opened to the maximum, that is, the air vent film can be directly supported to the south edge of the back slope of the greenhouse. Exhaust of air.
Regarding the air vents on the front face of the greenhouse, vegetable farmers can directly support the film to the lamination wire on the front face of the greenhouse, and increase the amount of cold air entering the greenhouse by increasing the ventilation openings to accelerate the air movement and reduce the greenhouse temperature.
Because the current temperature is generally not lower than 15 ℃. Therefore, as long as it is sunny and favorable terrain, vegetable farmers can open the upper and lower air vents of the products day and night, and close the upper and lower air vents of the greenhouse when the temperature is low at night or when it is raining.
Regarding the greenhouse with 60-mesh insect-proof net, vegetable farmers do not need to install windscreen. When vegetable farmers installed windshield films in the early years, they were all to prevent the cool wind from outside the shed from blowing into the shed, and to prevent chapped skin of tomato fruits cultivated in the shed.
Now after using high-density insect-proof nets, the insect-proof nets will form a certain barrier to the cold air outside the shed, slow down the speed of the cold air entering the greenhouse, and make the cold air preheat during the process of entering the greenhouse, which can also prevent the cold air from entering the greenhouse. The skin of the tomatoes is chapped.
In the greenhouse equipped with high-density insect-proof nets, the windshield film will also affect the air circulation in the greenhouse, which will reduce the ventilation and cooling effect of the greenhouse. Therefore, vegetable farmers should remove the windshield film in the shed.