ABSTRACT
In the year 2035, the global population wil l have doubled, an d 75 % o f th e population wil l b e living i n cities. This means a tremendous growth in urban areas , an unprecedented concentratio n in the consumption o f energy an d material i n certai n regions, and a very intensiv e us e of lan d and natural resources. The mai n materia l flux withi n this system , the Anthroposphere, goe s into the process "constructio n of building s an d networks". The urban infrastructure thu s contains a large stoc k of materials ; in the future , the efficient managemen t o f thi s stock may becom e crucial in terms o f resources a s well a s environmental impacts .
