Glossary - The impact of Green Roofs on the Urban Ecosystem

Albedo: Ratio of the amount of light reflected by a surface to the amount of incident light. A surface with a higher albedo has a higher reflectivity.

Ecological niche: The role of an organism in a community in terms of the habitat it occupies, its interactions with other organisms and its effect on the environment.

Ecological succession: The natural process whereby communities of plant and animal species are replaced by others, usually more complex, over time as a mature ecosystem develops.

Ecosystem services: The benefits people obtain from ecosystems.

Evapotranspiration: Loss of water from the soil by transpiration of the plants growing thereon.

Genus: A taxonomic rank in biological classification. The hierarchy of the classification from general to specific is: Domain -> Kingdom -> Phylum -> Class -> Order -> Family -> Genus -> Species.

Habitat fragmentation: A process wherein habitat is destroyed, resulting in a smaller and more isolated remaining habitat.

Invasive species: An organism that is introduced into a new environment, where it is not native (also known as an exotic or nuisance species).

Monoculture:Large area covered by a single species (or for crops, a single variety) of plants, especially if grown year after year.

Pioneer species: First species that colonize a bare site at the first stage in ecological succession.

Refuge: An area that has remained unaffected by environmental changes to the surrounding area, such as a mountain area that was not covered with ice during the Pleistocene, and in which, therefore, the previous flora and fauna has survived.

Wildlife corridor: In urban and suburban areas, narrow continuous areas of favourable habitat which connect built-up areas with the country and allow the movement of animals, birds and plants along them.