(Health-NewsWire.Net, December 17, 2015 ) Artificial grow lights and street lamps used for growing plants indoors has been found to affect the growth and flowering of plants and even the number of insects that depend on those plants for food. The research shows that light pollution has an impact on natural environment in complex ways. Due to the global extent of artificial light at night, there are concerns that these ecological impacts may be widespread.
Researchers from the University of Exeter stimulated the effects of street lighting on artificial grassland plots containing a community of invertebrates at night, exposing them to two different types of light treatment – a white light that is similar to newer commercial LED street lights and an amber light stimulating the type of sodium street lamp still found in much of the UK.
The experiments studied both top-down ad bottom-up effects of the lights on the population density of a species of pea aphid and in the presence and absence of predators including ladybirds. It was found that low intensity amber light was shown to inhibit, rather than induce flowering in greater bird's foot trefoil, a wild relative of peas and beans that is a key source of food for the pea aphid in grasslands and road verges. In mid summer, aphids feed on the flowering shoots, and the number of aphids was significantly suppressed under the light treatment in mid August due to the limited amount of food available.
Professor Kevin Gaston, Director of the Environment and Sustainability Institute (ESI) said “ these are the first findings from major long term experiments being funded by the European Research Council and already reveal how profound the impacts of artificial night time lighting can be on even simple communities of organisms.”
Dr. Jonathan Bennie of the ESI added, “our results suggest that by lighting up our night time environment we trigger complex effects on natural food webs. While we are all aware that street lights often attract insects at night, we show that they may have more permanent, widespread impacts on wildlife and ecosystems.” This paper was a part off a special themed issue of the journal entitled - “ the biological impacts of artificial light at night; from molecules to communities”.
