2025/02/18 by Jérémy Fonvielle, Lukas Thuile Bistarelli, Yile Tao +16 · 1 voice
Earth and Planetary Sciences · Environmental Science · #Impact of Light on Environment and Health #Isotope Analysis in Ecology #Marine and coastal ecosystems
paper · doi:10.1016/j.watres.2025.123315
openalex publication_date 2025/02/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/22
• Skyglow changes the structure of microbial communities at the DNA and RNA level. • Skyglow increases the abundance of cyanobacteria and the concentration of microbes. • Skyglow alters the ecosystem metabolome by increasing the proportion of algalderived compounds. • Skyglow alters bacteria-bacteria interactions and can act as a selection pressure on microbes. Artificial light propagating towards the night sky can be scattered back to Earth and reach ecosystems tens of kilometres away from the original light source. This phenomenon is known as artificial skyglow. Its consequences on freshwaters are largely unknown. In a large-scale lake enclosure experiment, we found that skyglow at levels of 0.06 and 6 lux increased the abundance of anoxygenic aerobic phototrophs and cyanobacteria by 32 (±22) times. An ecosystem metabolome analysis revealed that skyglow increased the production of algal-derived metabolites, which appeared to stimulate heterotrophic activities as well. Furthermore, we found evidence that skyglow decreased the number of bacteria-bacteria interactions. Effects of skyglow were more pronounced at night, suggesting that responses to skyglow can occur on short time scales. Overall, our results call for considering skyglow as a reality of increasing importance for microbial communities and carbon cycling in lake ecosystems.