Field experiment
Image by James Duffy
Twenty-four 16 m2 plots (n = 6 per treatment) have been illuminated at night (in addition to six unlit control plots) in a previously artificial light naïve grassland ecosystem with different lighting treatments: cool white LED lighting equivalent to that experienced at ground level under LED street lighting, LED street lighting that is dimmed by 50%, LED street lighting that is both dimmed and timed to switch off between midnight and 04:00 am, and amber LED lighting with a spectral peak at 588 nm (approximating that of the low-pressure sodium street lighting widely used during the mid- to late twentieth century). Lights were switched on in April 2012 and maintained thereafter.
In this experiment mobile organisms have the opportunity to move away from or into lighting treatments. We have found that modern LED lighting can have impacts on the structure and composition of ground-dwelling invertebrate assemblages.