Invasive Species

 

Invasive species is a phrase with several definitions, but the term is most often used to describe non-indigenous species (i.e. plants or animals) that adversely effect the habitats they invade either economically, environmentally or otherwise. They cause major environmental concerns in country's throughout the world. It has been used in this sense by government organizations as well as conservation groups such as the IUCN. However, the term can also be extended to include both native and non-native species that heavily colonize a particular habitat. Yet another use of the word is for a widespread non-indigenous species, which is particularly misleading as not all non-indigenous species necessarily have an adverse effect on their adopted environment. An example of this use includes claims that the common goldfish (Carassius auratus) is invasive, but while it is common outside of its range globally, it almost never appears in harmful densities. Due to the ambiguity of the phrase, it is often criticized as an imprecise term within the field of ecology.

 

Light Pollution

 

Light pollution is excess or obtrusive light created by humans. Among other effects, it disrupts ecosystems, can cause adverse health effects, obscures stars to city dwellers, interferes with astronomical observatories, and wastes energy. Light pollution can be construed to have two main branches: (a) annoying light that intrudes on an otherwise natural or low light setting and (b) excessive light, generally indoors, that leads to worker discomfort and adverse health effects. Since the early 1980s, a global dark-sky movement has emerged, with concerned people campaigning to reduce the amount of light pollution.

 

With recent advances in private spaceflight, the prospect of space-based orbiting billboards appearing in the near future has provoked concern that such objects may become another form of light pollution. With this in mind, the United States Federal Aviation Administration sought permission, in May 2005, to enforce a law prohibiting "obtrusive" advertising in earth orbit.

 

Noise Pollution

 

Noise pollution (or environmental noise in technical venues) is displeasing human or machine created sound that disrupts the environment. The dominant form of noise pollution is from transportation sources, principally motor vehicles.

 

Radio Spectrum Pollution

 

Radio spectrum pollution is the straying of waves in the radio and electromagnetic spectrums outside their allocations that cause problems for some activities. It is a specialized form of light pollution, and of particular concern to radio astronomers.

 

Visible Pollution

 

Visual pollution is the term given to unattractive visual elements of a vista, a landscape, or any other thing that a person might want to look at. Commonly cited examples are billboards, litter, graffiti, overhead powerlines, utility poles, contrails, skywriting, buildings, signs, weeds and advertisements.