Noise pollution

About: Noise pollution is a research topic. Over the lifetime, 4455 publications have been published within this topic receiving 67192 citations.

Separating the Noise from the Noise: A Finding in Support of the “Niche Hypothesis,” That Birds are Influenced by Human-Induced Noise in Natural Habitats

Abstract: Controlling for the confounding influence of physical disturbance, it was possible to test the hypothesis that ambient noise alone would play a role in structuring bird communities in riparian habitats in Boulder, Colorado, USA. Point counts of birds were conducted in open space/minimally disturbed, residential, commercial and industrial neighborhoods. Within the same disturbance parameters and land use, species richness and PIF scores (a weighted value based on species' importance) consistently and significantly decreased as ambient noise increased. These results can be viewed as support for the “Niche Hypothesis” (Krause 1987, 1998), that wildlife species' acoustic niches are adversely affected by human-induced noise pollution.

Effects of traffic noise on tree frog stress levels, immunity, and color signaling

Abstract: During the last decade, many studies have focused on the detrimental effects of noise pollution on acoustic communication. Surprisingly, although it is known that noise exposure strongly influences health in humans, studies on wildlife remain scarce. In order to gain insight into the consequences of traffic noise exposure, we experimentally manipulated traffic noise exposure as well as the endocrine status of animals to investigate physiological and phenotypic consequences of noise pollution in an anuran species. We showed that noise exposure increased stress hormone level and induced an immunosuppressive effect. In addition, both traffic noise exposure and stress hormone application negatively impacted H. arborea vocal sac coloration. Moreover, our results suggest profound changes in sexual selection processes because the best quality males with initial attractive vocal sac coloration were the most impacted by noise. Hence, our study suggests that the recent increases in anthropogenic noise worldwide might affect a broader range of animal species than previously thought, because of alteration of visual signals and immunity. Generalizing these results to other taxa is crucial for the conservation of biodiversity in an increasingly noisy world.

Visualization of pass-by noise by means of moving frame acoustic holography.

Abstract: The noise generated by pass-by test (ISO 362) was visualized. The moving frame acoustic holography was improved to visualize the pass-by noise and predict its level. The proposed method allowed us to visualize tire and engine noise generated by pass-by test based on the following assumption; the noise can be assumed to be quasistationary. This is first because the speed change during the period of our interest is negligible and second because the frequency change of the noise is also negligible. The proposed method was verified by a controlled loud speaker experiment. Effects of running condition, e.g., accelerating according to ISO 362, cruising at constant speed, and coasting down, on the radiated noise were also visualized. The visualized results show where the tire noise is generated and how it propagates.