Duarte Cristian, Quintanilla-Ahumada Diego, Anguita Cristóbal, Silva-Rodriguez Eduardo A, Manríquez Patricio H, Widdicombe Stephen, Pulgar José, Miranda Cristian, Jahnsen-Guzmán Nicole, Quijón Pedro A
Departamento de Ecología y Biodiversidad, Facultad de Ciencias de la Vida, Universidad, Andrés Bello, Santiago, Chile; Centro de Investigación Marina Quintay (CIMARQ), Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago, Chile.
Departamento de Ecología y Biodiversidad, Facultad de Ciencias de la Vida, Universidad, Andrés Bello, Santiago, Chile; Programa de Doctorado en Medicina de la Conservación, Universidad Andrés Bello, Santiago, Chile.
Sci Total Environ. 2023 May 10;872:162086. doi: 10.1016/j.scitotenv.2023.162086. Epub 2023 Feb 9.
Artificial light at night (ALAN) is a pervasive but still under-recognized driver of global change. In coastal settings, a large majority of the studies assessing ALAN impacts has focused on individual species, even though it is unclear whether results gathered from single species can be used to predict community-wide responses. Similarly, these studies often treat species as single life-stage entities, ignoring the variation associated with distinct life stages. This study addresses both limitations by focusing on the effects of ALAN on a sandy beach community consisting of species with distinct early- and late-life stages. Our hypothesis was that ALAN alters community structure and these changes are mediated by individual species and also by their ontogenetic stages. A field experiment was conducted in a sandy beach of north-central Chile using an artificial LED system. Samples were collected at different night hours (8-levels in total) across the intertidal (9-levels) over several days in November and January (austral spring and summer seasons). The abundance of adults of all species was significantly lower in ALAN treatments. Early stages of isopods showed the same pattern, but the opposite was observed for the early stages of the other two species. Clear differences were detected in the zonation of these species during natural darkness versus those exposed to ALAN, with some adult-juvenile differences in this response. These results support our hypothesis and document a series of changes affecting differentially both early and late life stages of these species, and ultimately, the structure of the entire community. Although the effects described correspond to short-term responses, more persistent effects are likely to occur if ALAN sources become established as permanent features in sandy beaches. The worldwide growth of ALAN suggests that the scope of its effect will continue to grow and represents a concern for sandy beach systems.
夜间人造光（ALAN）是一种普遍存在但仍未得到充分认识的全球变化驱动因素。在沿海地区，大多数评估ALAN影响的研究都集中在单个物种上，尽管尚不清楚从单一物种获得的结果是否可用于预测整个群落的反应。同样，这些研究通常将物种视为单一生命阶段的实体，忽略了与不同生命阶段相关的变异。本研究通过关注ALAN对一个由具有不同早期和晚期生命阶段的物种组成的沙滩群落的影响，解决了这两个局限性。我们的假设是，ALAN会改变群落结构，而这些变化是由单个物种及其个体发育阶段介导的。在智利中北部的一个沙滩上使用人工LED系统进行了一项野外实验。在11月和1月（南半球的春季和夏季）的几天里，在潮间带的不同夜间时段（总共8个水平）和不同潮位（9个水平）采集样本。在ALAN处理中，所有物种成虫的丰度均显著降低。等足类动物的早期阶段呈现相同模式，但其他两个物种的早期阶段则相反。在自然黑暗与暴露于ALAN的情况下，这些物种的分带存在明显差异，在这种反应中存在一些成虫与幼虫的差异。这些结果支持了我们的假设，并记录了一系列对这些物种的早期和晚期生命阶段产生不同影响的变化，最终影响了整个群落的结构。尽管所描述的影响对应于短期反应，但如果ALAN源在沙滩上成为永久性特征，可能会产生更持久的影响。全球范围内ALAN的增长表明其影响范围将继续扩大，这对沙滩系统来说是一个令人担忧的问题。
