Noise pollution

 

        Noise pollution (or environmental noise) is displeasing human- or machine-created sound that disrupts the activity or balance of human or animal life. A common form of noise pollution is from transportation, principally motor vehicles. The word "noise" comes from the Latin word nausea meaning "seasickness", referring originally to nuisance noise. And the source of noise pollution can be the followings:

 

§             transportation systems-including motor vehicle noise, aircraft noise and rail noise

§             poor urban planning- since side-by-side industrial and residential buildings can result in noise pollution in the residential area

§             car alarms

§             office equipment

§             factory machinery

§             construction work

§             audio entertainment systems

§             noisy people

 

Noise pollution not only affects human, but also the environment. To help the environment to help human ourselves, let us study those effects caused by noise:

 

Human health effects

 

a)  Physiological

Noise pollution can cause annoyance and aggression, hypertension, high stress levels, tinnitus, sleep disturbances, and other harmful effects. Furthermore, stress and hypertension are the leading causes to health problems, whereas tinnitus can lead to forgetfulness, severe depression and at times panic attacks.

 

b)  Psychological

Chronic exposure to noise may cause noise-induced hearing loss. A comparison of Maaban tribesmen, who were insignificantly exposed to transportation or industrial noise, showed that chronic exposure to moderately high levels of environmental noise contributes to hearing loss.

 

High noise levels can also contribute to cardiovascular effects and exposure to moderately high levels during a single eight hour period causes a statistical rise in blood pressure of five to ten points and an increase in stress and vasoconstriction leading to the increased blood pressure noted above as well as to increased incidence of coronary artery disease.

 

Environmental effects

 

Noise can have a detrimental effect on animals by causing stress, increasing risk of mortality by changing the delicate balance in predator/prey detection and avoidance, and by interfering with their use of sounds in communication especially in relation to reproduction and in navigation. Acoustic overexposure can lead to temporary or permanent loss of hearing.

 

An impact of noise on animal life is the reduction of usable habitat that noisy areas may cause, which in the case of endangered species may be part of the path to extinction. One of the best known cases of damage caused by noise pollution is the death of certain species of beached , brought on by the loud sound of military sonar.

 

Noise also makes species communicate louder, which is called Lombard vocal response. Scientists and researchers have conducted experiments that show whales' song length is longer when submarine-detectors are on. If creatures don't "speak" loud enough, their voice will be masked by anthropogenic sounds. These unheard voices might be warnings, finding of prey, or preparations of net-bubbling. When one species begins speaking louder, it will mask other species' voice, causing the whole ecosystem to eventually speak louder.

 

Zebra finches become less faithful to their partners when exposed to traffic noise. This could alter a population's evolutionary trajectory by selecting traits, sapping resources normally devoted to other activities and thus lead to profound genetic and evolutionary consequences