Impact of artificial light at night on diurnal plant-pollinator interactions

Abstract

Artificial light at night has rapidly spread around the globe over the last decades. Evidence is increasing that it has adverse effects on the behavior, physiology, and survival of animals and plants with consequences for species interactions and ecosystem functioning. For example, artificial light at night disrupts plant-pollinator interactions at night and this can have consequences for the plant reproductive output. By experimentally illuminating natural plant-pollinator communities during the night using commercial street-lamps we tested whether light at night can also change interactions of a plant-pollinator community during daytime. Here we show that artificial light at night can alter diurnal plant-pollinator interactions, but the direction of the change depends on the plant species. We conclude that the effect of artificial light at night on plant-pollinator interactions is not limited to the night, but can also propagate to the daytime with so far unknown consequences for the pollinator community and the diurnal pollination function and services they provide.

Matthew effect: common species become more common and rare ones become more rare in response to artificial light at night

“…In addition to direct effects, we expected that ALAN might also have indirect effects on alien plant invasion via other trophic levels. This is because alien plants often attract different numbers and types of insects than native plants do 35,36,38 , and ALAN could also modify plant-insect interactions 7,9,31,32 . Our study, however, found no evidence that insect exclusion mediated the effects of ALAN on alien and native plants.…”

“…Light pollution due to artificial light at night (ALAN) has increased dramatically in the last century, and has altered the natural night-time environment in large areas of the Earth 1,2 . As a consequence, ecological impacts of ALAN have become an important focus for global change research in recent years [3][4][5][6][7][8][9] . To date, most research on the impact of ALAN has focused on the behavior, physiology, and life history of animals [10][11][12][13] , and only a few studies have focused on plants 6,12,14 .…”

“…ALAN can also affect other organisms such as insects 9,[28][29][30] , which could play very important roles, e.g. as herbivores and pollinators, in regulating plant growth and reproduction.…”

“…as herbivores and pollinators, in regulating plant growth and reproduction. Consequently, ALAN could indirectly affect plants by modifying plant-insect interactions 7,9,28,[31][32][33] . Furthermore, alien plants, due to their evolutionary novelty, might attract different numbers and types of herbivores [34][35][36] and pollinators [37][38][39] than native plants.…”

11 Pressing Research Questions on How Light Pollution Affects Biodiversity

“…Global environmental pressures threaten biodiversity directly through changes in species' physiology and behavior, and indirectly through interactions between impacted species and other species within ecological communities (Tylianakis et al, 2008). To date only a few studies have quantified indirect effects of ALAN caused by altered species interactions within (Knop et al, 2017;Giavi et al, 2020Giavi et al, , 2021, or across trophic levels (Bennie et al, 2018;Manfrin et al, 2018;Maggi et al, 2020), and we are far from being able to predict where indirect effects occur and their likely importance for the wider ecosystem.…”