Natural sources of light like the sun and the moon have
a significant impact on the biological activity of plants and
microorganisms as well as on the instincts of people and
animals. Moonlight helps animals – and specifically insects,
of which there are by far the most species on Earth – navigate
in the dark. Other factors that determine the life of all living
things are light-dark changes, the direction of the light and
its rhythm, meaning the number of daylight hours each day.
Artificial light – especially light with high blue light content –
attracts animals, especially insects and birds. It can severely
disrupt life’s natural rhythms. And there are consequences:
reproductive and foraging activities are impaired, and some
may even die in the vicinity of artificial light sources.
The negative impact on the ecosystem as a whole can only
be minimised if we avoid any harm caused by light.
Our focus must be on responsible outdoor lighting that
addresses the fundamental relevance of illumination to ensure
safety and create identity. It brightens our living spaces, but
must at the same time avoid adverse effects on animals as
much as possible – in nature as well as in urban environments.
The effect and significance of
artificial light
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