The emergence of the Internet of Things gave birth to intelligent agriculture. With the continuous development of agricultural science and technology, the agricultural planting structure is also constantly developing and improving. The enhancement of scientific awareness and the continuous renewal of fine varieties have greatly increased the yield of crops. However, in the face of the huge growth potential of agricultural production, the development of agricultural production has been plagued by some problems, such as the contradiction between the large demand for carbon dioxide in crop growth and the serious shortage of carbon dioxide in the atmosphere.

China currently has more5000More than ten thousand mu of greenhouse, annual output value of about5000billion yuan, of which80% of the output value comes from winter, spring and autumn, because the output value of vegetables in these three seasons is very high, per mu20000-30000Yuan. However, in these three seasons, the greenhouse has limited ventilation for nearly five months, and the concentration of carbon dioxide is insufficient, which severely limits the production of vegetables.

Carbon dioxide in agriculture is one of the raw materials for photosynthesis of green plants, and 95% of the dry weight of crops comes from photosynthesis. Therefore, carbon dioxide has become an important factor affecting crop yields.

In order to maintain the temperature of vegetable production in the greenhouse in winter, the greenhouse is usually kept closed, which causes the air in the greenhouse to be relatively blocked and cannot be supplemented with carbon dioxide in time. After sunrise, due to the accelerated photosynthesis of vegetables, the carbon dioxide concentration in the shed drops sharply, sometimes falling below the carbon dioxide compensation point (0.008-0.01%). Vegetable crops can hardly carry out normal photosynthesis, affecting the growth and development of vegetables, causing diseases and reducing yields.

Warm and humid agricultural greenhouse cultivation can keep crops in a relatively closed place for a long time. The concentration of carbon dioxide in the shed varies greatly within a day. It peaked at 1000 to 1200 ppm before sunrise and dropped to about 100 ppm to 330ppm within 2.5 to 3 hours after sunrise, and continued to rise until 2 hours in the afternoon, returning to atmospheric levels around 4 pm.

The concentration of carbon dioxide required for crops is usually 1000-1500ppm. Therefore, the lack of carbon dioxide in plastic greenhouses is very serious, which has become an important factor affecting the yield of vegetables in plastic greenhouses. However, at the same time of monitoring CO2, the high humidity condensation environment at night reached 100%, which caused great trouble to most non-dispersive infrared sensors on the market.

In view of this situation, the installation of carbon dioxide sensors in agricultural greenhouses can ensure that the alarm is issued in time when the concentration of carbon dioxide monitors is insufficient, so that gas fertilizers can be used to ensure the normal growth of crops. The recommend uses the South Korea SOHA carbon dioxide CO2 sensor module SH-DS, which is a dual-wave non-dispersive infrared detection principle. The detection range is relatively wide, in the range of 0 ~ 3000ppm/5000ppm. In addition, the CO2 sensor module is SH-DS coated with waterproof paint to withstand high humidity due to condensation problems in agricultural greenhouses at night.