AC/DC vs Beetles

Heavy rock does not do well for the eating habits of beetles and thus adversely affects crops. Is it possible to infer from this the wider effects of noise pollution on the environment?

The seventh album of the Australian heavy rock band AC / DC was released in July 1980, and the last song called: “Rock 'n' roll is not noise pollution”.

A recent research by Dr. Brendon Burton, an ecologist who decided to seriously examine this thesis or at least the effects of noise pollution on ecosystems. According to the findings, in a study published in the journal Ecology and Evolution, noise pollution does harm the interaction of animals with their environment, in this case, in the food webs.

Noise pollution has long been known to have adverse effects on the health of animals and humans.

In humans, there was also a certain increase in morbidity and death associated with the circulatory system due to long-term exposure to noise in vehicles. Noise pollution from human activities at sea - shipping, resource extraction and even diving - disrupts communication, reproductive cycle and other activities of marine mammals. Noise also has a negative effect on many other species - for example, owls' hunting capabilities - and is found not only in cities and other towns but also in nature reserves.

Barton and his colleagues believed that much of the research done so far focused on the direct impact of noise on the behavior of individual animals and that it was also useful to examine the impact of pollution on interactions with their species and other species

Ladybug against the ants

The study focused on the species of Harmonia Axyridis of beetles from the Mushait family (which also belongs to the Seven Mushroom or the Ladybug); The species tested is a natural enemy of aphid that harms soybeans and therefore its presence is desirable in the breeding fields as a means of biological control. The question is whether strong (and high quality) rock music will change the eating habits of beetles - for example, will they be less harmful? In other words, this special study examined whether enjoying AC-DC means less tofu?

To test the hypothesis, the larvae were placed in enclosed places with a fixed number of pests. In each experiment, their prey activities were examined in quiet conditions, ie, without exposure to noise, or under exposure to music from various stylists - rock, folk, country - and urban background noise, such as an ambulance siren or a plane, at about 100 decibels, Which operates nearby.

In counting the number of anemias it turned out that the larvae reacted negatively to heavy rock and so did the urban noises: listening to them reduced the rate of prey by about half. The decrease in predation rate was measured within approximately 15 hours to 24 hours.

The researchers also examined the interaction and ecological context: To eliminate possible effects, the researchers examined whether exposure to rock music affected the anemone population or soybean growth separately - in both cases, there was no effect. When soybeans, aphids, and beetles were raised together, without exposure to noise, the beetles reduced the population of the insect almost entirely and the soy developed well. In other words, natural pest control works. However, when the system was tested under musical noise pollution - in this case "listened" in this simple ecosystem to the AC / DC mix 24 hours in a row for two weeks (!) - 40 times more aphids, and plants grew by a quarter.

In fact, as a result of the direct impact of noise on the beetles, which caused a decrease in their eating rate, indirect effect on the size of the anemone population was indirectly affected by the biomass of the plants.

"This study is indeed anew because of the focus on insects, not on vertebrates, such as birds or frogs, which have so far focused on research, and on the implications for the entire ecological community, not just the individual," says Dr. Oded Berger-Tal, The relationship between animal behavior and the preservation of nature.

"Noise pollution disrupts behavior in two ways. First, it synthesizes sound signals that the animal needs to function, and when it is absorbed, its functioning is impaired. In addition, noise causes a distraction - the animal hears the sounds but the behavioral response is impaired even though they are absorbed. That's probably what happens to the beetles. This is similar to people who function much less well under external interference, "explains Berger-Tal.

In the study, incidentally, there was no positive association between music and aphids. In other words, there is no noise source that encourages the insecticide.

The domino effect of noise

Although these are laboratory conditions, the study indicates a domino effect of noise pollution that spreads through interactions in the ecosystem. The noise used in research is similar in magnitude to the noise of a tractor working in the agricultural field, and here lies the importance of this entertaining study: noise from a human source harms desirable environmental behaviors, such as natural pest control.

Along with other environmental changes, the proximity of urban noise sources to agricultural crops due to the ongoing trend of porphyry also has effects that may be relevant to home gardening, which also has a system of pests and their natural enemies.

"Israel is so dense and its infrastructure is so close to habitats, natural and agricultural, and it can be assumed that noise pollution does harm our ecosystems," says Berger-Tal. "It also happens in nature reserves with the traffic of travelers and apparently, like the direction that the article points to, the interaction between agriculture and nature."

"It is very difficult to completely eliminate the pollution of the noise, but it is desirable to give it a more significant place in public awareness and it is also important to address planning processes," concludes Berger-Tal. "This is also true of constant exposures, for example when designing a location for wind turbines that are a constant and monotonous source of noise, but no less so for spot noise, such as Independence Day fireworks or performances on open sites, which create a sharp and acute disturbance."

EDB-China Shanghai 8 August 2018