Monday, January 19, 2009

ELP or PLP, or both?

ELP, ecological light pollution, is light that occurs when it shouldn’t i.e. at night or in places where it is normally dark. This permits animals and insects to be mobile when, under normal circumstances they would be asleep.

PLP, polarised light pollution, is much more of a problem in than it can occur either during daylight or at night. Many organisms require ‘light’ to see but, additionally, many birds, insects and reptiles have developed the ability to utilise polarised light. The primary source of natural polarised light is water but in today’s environment asphalt, gravestones, cars, plastic sheeting, floating plastic waste and glass windows all have a polarised light signature that can overwhelm natural levels. This creates problems for those animals that have utilised polarised light in order to structure their lifecycle, particularly aquatic animals, or those that rely heavily upon water. We have all heard of birds flying into buildings and swans landing on roads – it is all to do with the polarised light signature in that they think they are landing on water.

Published in Frontiers in Ecology and the Environment is recent research that indicates that polarised light emanating from structures within the built environment can overwhelm natural cues controlling animal behaviour. Researchers have suggested that, despite the growing human impact on certain communities of animals, the worst examples of PLP could be reduced: use of alternative building materials or employing methods to mitigate the problem, such as adding white curtains to dark windows or adding white markings on road surfaces.
The team's findings could also offer conservationists an alternative way to deal with problematic species, such as insects destroying trees – by creating a massive polarised light traps to ‘crash’ bark beetle populations.



Post a Comment

<< Home