Light pollution is the deleterious effect of urban and suburban artificial lights, used by man in inhabited areas and in the connecting roads between them, mainly caused by poor lighting engineering design and therefore by reckless energy abuse.
Light pollution leads directly to further environmental chemical pollution due to excess energy production, also partly increasing unnecessary global warming. Light pollution is basically the disruption of unnecessary natural ambient lighting at night.
The most used legislative definition qualifies it as any radiation of direct light outside the areas to which it is functionally dedicated, and in particular towards the celestial vault. This alteration causes damage of various kinds: environmental, scientific, cultural and economic.
Every year a day of reflection is celebrated on this theme, which has become a very important global problem.
The effects of light pollution on migratory animal behavior
The study The effects of light pollution on migratory animal behavior, published in the Trends in ecology & evolution, told: "Light pollution is a global threat to biodiversity, especially migratory organisms, some of which traverse hemispheric scales.
Research on light pollution has grown significantly over the past decades, but our review of migratory organisms demonstrates gaps in our understanding, beyond particularly migratory birds. Research across spatial scales reveals the multifaceted effects of artificial light on migratory species, ranging from local and regional to macroscale impacts.These threats extend beyond species that are active at night - broadening the scope of this threat.
Emerging tools for measuring light pollution and its impacts, as well as ecological forecasting techniques, present new pathways for conservation, including transdisciplinary approaches." Among the environmental damages we can list: difficulty or loss of orientation in various animal species, migratory birds, sea turtles, nocturnal moths, bats, photoperiod alteration in some plants, circadian rhythm alteration in plants, animals and microorganisms, growth stunted periphyton[.
For example, the production of melatonin is already blocked at very low light levels and this causes sleep disturbance. In 2001, a new retinal photoreceptor was discovered in the eye which does not contribute to the mechanism of vision, but regulates our biological clock.
The peak sensitivity of this sensor is in the blue part of the visible spectrum and for this reason, lamps with a strong blue cast are the ones that can most alter our circadian rhythms. While the lamps that cause less damage, from this point of view, since they have a dominant red color of the visible spectrum, are the high pressure sodium ones, and even less harmful, the low pressure ones.