Let the light lead to growth for all

    29-Jan-2020
-Debapriya Mukherjee
Contd from previous issue
For example, sea turtles hatch when its dark and the hatchlings use the light over the water to return to the ocean. Light from the buildings on the beaches draws hatchlings away from the water. But bright ALAN originating from high rises, resorts, bars, malls, restaurants, and homes  along the coastlines create countless false moons and alluringly bright horizons, and the tiny turtles get disoriented and wander into roads  in huge numbers. For a hatchling, each minute on land means dodging an array of winged, wheeled, and walking dangers. When the sun comes up, a disoriented, land-locked turtle is almost literally toast—dehydrated, overheated, and easy pickings for predators. As a result, millions of sea turtles die every year in Florida. Light pollution can also meddle with aquatic life in lakes. Zooplankton  normally dwell deep below the water in the day and ascend to the surface at night to feed on algae. But ALAN impedes zooplanktons from consuming surface algae which leads to algal blooms that may disrupt plant life and lower the water quality.
Habitats that are exposed to increased ALAN due to anthropogenic activities  face a variety of other man-made abiotic stressors including noise, chemical contamination, or other effects related to changes in land use practices. ALAN—in combination with habitat loss, chemical pollution, invasive species, and climate change—is driving insect declines. An estimate of the effects of street lamps in Germany suggested that the light could wipe out more than 60 billion insects over a single summer.
Street lighting prevents moths pollinating as they end up flying into glare instead, exhausting themselves and leaving them vulnerable to predators. Therefore there is urgent need to put emphasis on the importance of keeping any disruption to natural system to an absolute minimum.
Best Solutions to pollution include turning off unnecessary lights  to save money and environment and putting shields on streetlights to direct beams downward to prevent skyglow. Keeping the lights off between midnight and dawn is enough to prevent the disturbance to animal behaviour that they trigger. For this, appropriate  management strategy is needed to reduce the level of light pollution. Awareness about  the health and environmental impacts of light pollution among communities can also be significant for curbing this problem especially in case of developing countries like India. Adequate understanding of light pollution and holistic approach involving stakeholder and community participation is necessary to minimize its consequences. Regulation of  light consumption in core urban areas simply to upgrade the visual look  can also be reduced by implementing laws to maintain the minimum level of light consumption.
The writer is former Senior Scientist, Central Pollution Control Board based in Kolkata and can be reached at 919432370163 & 916290099509 or [email protected]