夜间人造光(ALAN)威胁要破坏大多数自然栖息地和物种。包括那些在沿海地区的人,越来越多的研究已经确定了ALAN的影响。仔细检查这些影响背后的光特性对于更好地理解和管理这种压力源的影响很重要。这项研究的重点是ALAN单色波长,并研究了哪种类型的光谱改变了太平洋东南部两种主要沿海物种的自然活动:类动物两栖动物Orchestoideatuberculata和类等足类Tylosspinulosus。我们将这些生物的自然日光/夜间活动与它们暴露于五种不同的ALAN波长时表现出的活动进行了比较:紫罗兰色中的光,蓝色,绿色,琥珀色,和红色光谱。我们的工作假设是艾伦在晚上改变了这些物种的活动,但是这种影响的大小取决于光波长。在连续五天的24小时周期内以及在三个单独的实验中对活动进行的测量证实了这两个物种的自然昼夜节律活动模式,夜间活动强烈(~90%的可能性),白天几乎没有任何活动。然而,当暴露于ALAN时,在所有光波长下,这两个物种的活动均显着下降。有趣的是,两栖动物在夜间暴露于红灯时表现出中等的活动(~40%的概率),在两个实验中,当暴露于蓝色或琥珀色光时,等足动物将它们的一些活动转移到白天,提示该物种昼夜节律可能发生改变。总之,我们的结果与我们的工作假设一致,并建议艾伦减少夜间活动,一些波长对每个物种都有不同的影响。两栖类和等足类之间的差异可能与它们对自然弱光栖息地条件的不同适应有关,因此对艾伦有明显的敏感性。
Artificial Light at Night (ALAN) threatens to disrupt most natural habitats and species, including those in coastal settings, where a growing number of studies have identified ALAN impacts. A careful examination of the light properties behind those impacts is important to better understand and manage the effects of this stressor. This study focused on ALAN monochromatic wavelengths and examined which types of light spectra altered the natural activity of two prominent coastal species from the Pacific southeast: the talitroid amphipod Orchestoidea tuberculata and the oniscoid isopod Tylos spinulosus. We compared the natural daylight/night activity of these organisms with the one they exhibit when exposed to five different ALAN wavelengths: lights in the violet, blue, green, amber, and red spectra. Our working hypothesis was that ALAN alters these species\' activity at night, but the magnitude of such impact differs depending on light wavelengths. Measurements of activity over 24 h cycles for five consecutive days and in three separate experiments confirmed a natural circadian activity pattern in both species, with strong activity at night (∼90% of probability) and barely any activity during daylight. However, when exposed to ALAN, activity declined significantly in both species under all light wavelengths. Interestingly, amphipods exhibited moderate activity (∼40% of probability) when exposed to red lights at night, whereas isopods shifted some of their activity to daylight hours in two of the experiments when exposed to blue or amber lights, suggesting a possible alteration in this species circadian rhythm. Altogether, our results were consistent with our working hypothesis, and suggest that ALAN reduces night activity, and some wavelengths have differential effects on each species. Differences between amphipods and isopods are likely related to their distinct adaptations to natural low-light habitat conditions, and therefore distinct sensitivity to ALAN.