In a densely populated country like Germany, it is of vital importance to maintain the available space for many diverse uses, for example settlement, recreation and traffic, the production of food and renewable resources, economic and public use as well as nature conservation and its further development. At the same time, it is necessary to preserve land and soils and their ecological functions as the basis for life and a resource and habitat for humans, animals and plants and as an element of the ecosystem.

Furthermore, the growing use of space by settlements and traffic is leading to a vicious circle of traffic generation, expansion of traffic routes, enlargement of settlements and new traffic and a constant increase in material and energy consumption for additional buildings, vehicles and infrastructures, as well as additional noise, pollutants and greenhouse gas emissions.