How does noise become environmental pollution

Nature tips - nature conservation and species protection in practice

Noise and nature conservation
A loud problem
We live in a noisy world. Noise reduces the recreational value of the landscape and diminishes the quality of life. In the long run, noise is harmful not only to people, but also to animals. Many birds avoid busy roads and other noisy habitats (additional Information). In extreme cases, noise leads to the local disappearance of animal species. Noise is a problem even underwater. In the world's oceans, the noise level more than doubled in the 20th century. Great efforts are therefore necessary to reduce noise pollution and the associated negative effects on humans and animals.
Effects of Noise
•  Stress reactions and hearing damage.
Noise causes stress reactions in many vertebrate species, including humans, and has a negative effect on health. Damage to the inner ear occurs in bird and mammalian species between 90 and 140 dB (A). The human pain threshold is 120 dB (A). In contrast to birds, the hair cells in the inner ear of humans and many other mammals do not regenerate. Permanent damage is the result.
•  Disturbance of the perception of the environment.
Bats, but also whales and dolphins, orient themselves with the help of ultrasound. Based on the echo of their calls, they get an idea of ​​their environment. If there is a lot of noise, bats stop hunting for insects.
Nocturnal predators such as wild cats, martens and ermines hunt by ear. When the noise is annoying, it becomes difficult for them to catch prey. Unimpaired hearing is also crucial for prey. Noise affects escape behavior if robbers and alarm signals cannot be heard. In this way, noise affects the predator-prey ratios.
•  Many animal species communicate acoustically with one another. Calls are important for finding a partner, for demarcating the area and for establishing contact between parents and young animals. Noise can affect the reproductive success of birds (additional Information).
•  Triggering escape reactions.
Sudden noises put animals on alert and can trigger violent escape reactions - especially if the noise occurs together with optical stimuli, for example in a flying helicopter. Unforeseen disruptions have a particularly strong impact in less polluted regions.
Take protective measures Animals often have amazing adaptability and can also get used to some level of noise. In large cities, birds try to compensate for noise by singing louder (additional Information). Important factors for assessing the disruptive effect are the volume, the duration (one-time or permanent, regular or irregular) and the time of the exposure (day or night). The type of noise and the overlap from different noise sources are also important.
Not only the frequencies that humans perceive must be taken into account, as many animals also hear ultrasound and infrasound! The following threshold values ​​were defined as the basis for assessment: From a volume of 47 dB (A), permanent exposure to a reduction in the habitat suitability for noise-sensitive animal species must be assumed. 60 to 70 dB (A) are roughly equivalent to a 55% loss of living space, 90 dB (A) mean a 100% loss of living space in the long run (cf. Reck et al. 2001).
•  All technical means must be used to reduce noise pollution. For cars, for example, there are tires that cause less noise. A reduction in the maximum permissible speed also significantly reduces the stress caused by road traffic.
•  If noise cannot be avoided, the contaminated zone should be limited by protective measures as far as possible. Planted noise barriers have the best shielding effect. Noise barriers are also helpful. However, they increase the barrier effect of roads and rail lines. If they are transparent, there is also a risk of bird strikes. Woods reduce noise pollution by a few decibels if they are densely overgrown and wide.
=> more about the problem of landscape fragmentation
=> more about bird strikes
•  A uniform, area-wide noise pollution of the landscape is to be prevented. Noise sources should be bundled as far as possible, for example by expanding existing roads instead of building new ones.
•  In the future, the criterion "civilization noise" must acquire special significance in assessment procedures. Because, apart from the high mountains or some coastal regions, where can we find larger landscapes that are not impaired by noise emissions from traffic, economy, agriculture or recreational use? More quiet areas are needed, in which all noise generation is prohibited. Preserving the so-called "soundscape" - the natural background noise - is an indispensable part of comprehensive landscape protection.
=> more about landscape
Documents / links H. Reck (arr.) (2001): Noise and Landscape. Lectures of the conference "Effects of Noise and Planning Instruments for Nature Conservation" in Salzau Castle near Kiel on March 2nd and 3rd, 2000. Applied Landscape Ecology 44th Federal Agency for Nature Conservation, Bonn - Bad Godesberg, 160 pp.
H. Reck, J. Rassmus, GM Klump, M. Böttcher, H. Brüning, I. Gutsmiedel, C. Herden, K. Lutz, U. Mehl, G. Penn-Bressel, H. Roweck, J. Trautner, W Wende, C. Winkelmann & A. Zschalich (2001): Effects of noise and planning instruments for nature conservation. Results of a symposium - an overview. Nature conservation and landscaping 33 (5), pp. 145-149
A. Garniel, W. D. Daunicht, U. Mierwald & U. Ojowski (2007): Birds and traffic noise. Quantification and management of decisive impacts of traffic noise on avifauna. Final report R&D project 02.237 / 2003 / LR of the Federal Ministry of Transport, Building and Urban Development, Kiel Institute for Landscape Ecology, 273 pages, download pdf (10.356 kb)
K. Polachowski (2009): Animals in Noise. Effects and customization options. Internship, Building Department Canton Zurich - Noise Abatement Office, 19 pages, Download pdf (1.583 kb)
R. Stangl & J. Berger (2004): Investigation of the effectiveness of woody structures for noise and privacy protection on the Brenner motorway. Work report on behalf of Autostrada del Brennero S.P.A., Institute for Biological Engineering and Landscaping at the University of Natural Resources and Life Sciences, Vienna, 81 pages, download pdf (8,147 kb)
K. Stroh (2008): Noise - Road and Rail. UmweltWissen, Bavarian State Office for the Environment, 10 pages, download pdf (587 kb)
last change March 2009, © UMG