According to researchers at the Chinese Academy of Sciences, artificial light can help the leaves of Japanese pagoda trees and green ash trees fend off insect attacks.
They observed that the tree lines on streets in Beijing with street lighting suffered less damage from insects.
The strange influence of street lights on tree leaves in Beijing (Photo: Adobe).
The researchers collected over 5,500 leaves from more than 180 trees at 30 different locations throughout the city. Some leaves were taken from areas close to street lamps with the yellow light of sodium vapor lamps, while others were collected from places without any lighting.
They measured the size of the leaves, the water content in the leaves, and even the levels of nutrients and leaf toughness. Additionally, they observed signs of insect damage to the leaves and quantified the extent of this damage.
The leaves located in areas illuminated by street lights were healthier and less affected by insects. This indicates that street lights have some unexpected effects on tree leaves.
The researchers believe that further investigation is needed to determine the extent of this influence and to understand precisely why this light prevents insects from damaging the leaves.
One of the reasons the researchers speculate is that the light makes it easier for predatory species to see and catch insects before they can damage the leaves.
However, they also indicated that they would conduct more detailed studies to understand the behavior of insects in the presence or absence of nighttime lights, and to examine the direct effects of street lighting on tree leaves.
The initial assessment from the research team suggests that the impact of street light on tree leaves may be subtle.
Nevertheless, since this area is situated in the heart of Beijing and is urbanized, it is likely that the street lighting does not pose any threat to the diverse development of insects or to the ecosystem functions in the area.
