Micro-Climatic Variations in Naturally Ventilated Polyhouse Under Cucumber Cultivation

The experiment was carried out to investigate the seasonal variations of climatic parameters inside a naturally ventilated poly house during various stages of cucumber crop growth. Micro-climatic parameters such as ambient temperature (T), relative humidity (RH), light intensity (LI), and carbon dioxide (CO₂) were analyzed on daily basis in the polyhouse's vertical, spatial, and temporal scales. These parameters fluctuated at various stages of crop development. The weekly average maximum temperature of 38.73 °C was recorded in the polyhouse during the afternoon. The weekly average relative humidity (84.40%) was higher in the morning and lower in the afternoon (44.96 %). The light intensity inside the polyhouse was higher in the afternoon (43 klux) and lower in the morning and evening. The variations in CO₂ levels inside the polyhouse at different locations were observed to be very small. Micro-climate changes varied spatially and temporally within the polyhouse during crop growth. For every one-meter increase in height, the vertical gradient of temperature increased by 0.1°C and RHdecreased by about 1%.