Artificial Light at Night Alters Photosynthetic Electron Transport in Two Deciduous Species

Although light pollution is one of the fastest-growing environmental problems today, we still know little about its impact on specific organisms. Plants are the least understood group in this context. Although environmental observations may suggest some conclusions, we still need more specific experimental data. The present study involved two deciduous species-common beech (<i>Fagus sylvatica</i> L.) and white dogwood (<i>Cornus alba</i> L.)-which, after being placed in growth room, were exposed to additional light at night. The effect of two different nighttime lighting combinations on leaf physiology was analyzed by measuring chlorophyll fluorescence. Nighttime lighting caused disruptions in electron transport, as evidenced by the reduced RE₀/ET₀, RE₀/ABS, and PI_total parameters. This result confirms the negative impact of light pollution on plant functioning and provides a basis for further, more in-depth research.