Accessibility refers to the ease of reaching destinations. In addition to physical accessibility through transport infrastructure, connectivity through advanced telecommunication systems contributes to improving the intangible accessibility of areas.
Biodiversity or biological diversity means the variability among living organisms from all sources including, inter alia, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part; this includes diversity within species, between species and of ecosystems.
Natural Heritage can be divided in natural features, geological and physiographical formations, and natural sites, which are of outstanding universal value from the aesthetic, conservationist or scientific point of view.
Political Ecology studies human-environment interactions. It aims to examine how political, economic and social factors are linked to environmental problems,changes, and conflicts by exploring power structures.
Protected Area is a clearly defined geographical space, recognised, dedicated and managed, through legal or other effective means, to achieve the long-term conservation of nature with associated ecosystem services and cultural values” (IUCN)
Pollution is the introduction of substances or energy into the environment, resulting in deleterious effects of such a nature as to endanger human health, harm living resources and ecosystems, and impair or interfere with amenities and other legitimate uses of the environment.
Urban/Peri-Urban Development refers to urbanization with its different dimensions and perceptions and to non-urban population increase and sprawl of urbanized land that takes place beyond the city's or agglomeration's physical limits.