The diurnal trends of CO2 concentrations in glasshouses showed a relatively strong reliance on solar radiation and higher temperature varying between 25-35oC day and night, while relative humidity (RH) was maintained between 65 to 85%. Higher solar radiance during the midday intensified the assimilation of CO2 leading to declined concentration as little as 418 ppm at a height of 150 cm below mycelium CO2 bags and later showed a gradual increase on sunset as well as the absence of solar radiation. On overcast days with limited solar radiation, CO2
concentration was not reduced intensely due to the combined effect of plant and soil respiration as well as reduced photosynthesis. The effect of irrigation was generally not significant, possibly signifying suitable ventilation within root absorption in CO2 concentrations at height of 150 cm below the mycelium CO2 bags affected by soil management practice. The results obtained in glasshouse conditions and CO2 enhancement from the mycelium bags, however, agree with findings from model predictions stipulated by (Allen et al., 1971; Waggoner, 1969) in which water management practices and carbon sequestration from the soil would not be adequate to be efficiently utilised as natural fertiliser mostly due to the rapid loss of CO2 to the atmosphere resulting from turbulent mixing with other atmospheric gases.
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