Analysis of carbon fixation and humidification ability of indoor cultivation of Ficus pandurata Hance

Abstract

To investigate the impact of prolonged exposure to enclosed, low-light environments on carbon fixation and oxygen release in green plants, as well as their capacity to regulate transpiration and humidification, this study utilized Ficus pandurata Hance, a common indoor ornamental plant, as the experimental subject to examine the net photosynthetic rate (P_n) and transpiration rate (T_r). LI-6800 portable photosynthesizer was employed to assess the P_n and T_r of Ficus pandurata Hance cultivated under varying temperatures (15 ℃, 20 ℃, 25 ℃, 30 ℃, 35 ℃) and different CO₂ concentrations (400 µmol·mol⁻¹, 800 µmol·mol⁻¹, 1200 µmol·mol⁻¹) at different parts of the room (indoors or near windows). The results of the light response curve and the CO₂ response curve measurements indicate that the P_n of Ficus pandurata Hance shows a trend of initially increasing and then decreasing as the light intensity or CO₂ concentration increases. It is noteworthy that under different photosynthetically active radiation (PAR) and CO₂ concentrations, the maximum P_n of Ficus pandurata Hance cultivated by a window is significantly higher than that of indoor-cultivated plants. Under appropriate temperature control (20~30 ℃), the P_n and T_r of Ficus pandurata Hance are highest at 800 µmol·mol⁻¹ CO₂ concentration. Under appropriate ventilation conditions (CO₂ concentration < 1200 µmol·mol⁻¹), the plants have stronger carbon fixation ability under appropriate temperature conditions and stronger transpiration—induced humidification ability under non-low temperature (T ≥ 20 ℃) conditions. To sum up, in the case of high CO₂ concentration caused by poor indoor ventilation and dense population, cultivation of Ficus pandurata Hance by the window and proper control of temperature above 20 ℃ can obtain good ecological benefits of carbon fixation, oxygen release, transpiration and humidification.