Abstract: 1.Plants use light as a source of both energy and information. Plant physiological responses to light, and interactions between plants and animals (such as herbivory and pollination), have evolved under a more or less stable regime of 24-hour cycles of light and darkness, and, outside of the tropics, seasonal variation in daylength.
2.The rapid spread of outdoor electric lighting across the globe over the past century has caused an unprecedented disruption to these natural light cycles. Artificial light is widespread in the environment, varying in intensity by several orders of magnitude from faint skyglow reflected from distant cities to direct illumination of urban and suburban vegetation.
3.In many cases artificial light in the nighttime environment is sufficiently bright to induce a physiological response in plants, affecting their phenology, growth form and resource allocation. The physiology, behaviour and ecology of herbivores and pollinators is also likely to be impacted by artificial light. Thus, understanding the ecological consequences of artificial light at night is critical to determine the full impact of human activity on ecosystems.
4.Synthesis. Understanding the impacts of artificial nighttime light on wild plants and natural vegetation requires linking the knowledge gained from over a century of experimental research on the impacts of light on plants in the laboratory and greenhouse with knowledge of the intensity, spatial distribution, spectral composition and timing of light in the nighttime environment. To understand fully the extent of these impacts requires conceptual models that can (i) characterise the highly heterogeneous nature of the nighttime light environment at a scale relevant to plant physiology, and (ii) scale physiological responses to predict impacts at the level of the whole plant, population, community and ecosystem.

Abstract: Light is a key environmental factor influencing the growth, development and survival of aquatic organisms. We examined the effects of different light qualities (red, orange, white, blue, green or no light) and developmental stage at initial lighting [fertilized egg (FE), trochophore larva (TL), or eye-spot larva (EL)] on the growth, development, and survival of larvae of the Pacific abalone Haliotis discus hannai Ino. Larva-hatching success was significantly higher under blue, green, or no light compared with red, orange or white light (P < 0.05). Larval abnormalities were significantly increased under red, orange or white light compared with all other light qualities (P < 0.05). The incidence of metamorphosis in larvae illuminated from the TL stage was significantly higher under blue compared with other light qualities. Irrespective of the stage at initial illumination, the incidence of metamorphosis was lower in larvae cultured under red, orange or no light compared with other light qualities, but the differences were not significant (P > 0.05). Juvenile survival was significantly higher under blue or green compared with other light qualities (P < 0.05), with no significant effect of stage at initial illumination (P > 0.05). Larval size at completion of the shell was unaffected by stage at initial illumination, but was greater under blue or green light, while size at metamorphosis was greatest following illumination with blue or green light since the TL or EL stage (P < 0.05). Metamorphosis time was shortest with blue or green light and in cultures illuminated from the FE or TL stage (P < 0.05). Larval development from the FE to formation of the fourth tubule on the cephalic tentacles was fastest in larvae exposed since the FE or TL stage to blue or green light, compared with other light qualities (P < 0.05). However, there was no difference in terms of the rate of development from the FE to the TL stage between cultures lit or unlit since the FE egg stage (P > 0.05). These results suggest that a blue or green light source applied from the TL stage can increase the hatching and yield of H. discus hannai Ino, with important implications for the development of the aquaculture industry.

Abstract: Context: The sensitivity of melatonin to light suppression is expected to be higher in children since children have large pupils and pure crystal lenses. However, melatonin suppression by light in children remains unclear. Objective: We investigated whether light-induced melatonin suppression in children is larger than that in adults. Methods: Thirty-three healthy primary school children (mean age: 7.4 +/- 1.8 yr) and 29 healthy adults (mean age: 41.2 +/- 4.8 yr) participated in two experiments. In the first experiment, salivary melatonin concentrations in 13 children and 13 adults were measured at night under a dim light (< 30 lx) and moderately bright light (580 lx) in an experimental facility. Pupil diameters were also measured under dim light and bright light. In the second experiment, melatonin concentrations in 20 children and 16 adults were measured under dim light in the experimental facility and under room light at home (illuminance 140.0 +/- 82.7 lx). Results: In the experiment 1, the melatonin concentration was significantly decreased by exposure to moderately bright light in both adults and children. Melatonin suppression was significantly larger in children (88.2%, n=5) than in adults (46.3%, n=6) (p<0.01), although the data for some participants were excluded because melatonin concentrations had not yet risen. In the experiment 2, melatonin secretion was significantly suppressed by room light at home in children (n=15) (p<0.05) but not in adults (n=11). Conclusion: We found that the percentage of melatonin suppression by light in children was almost twice that in adults, suggesting that melatonin in children is more sensitive than that in adults to light at night.