Scaling laws in urban supply networks

In previous work, it has been proposed that urban structures may be understood as a result of self-organization principles. In particular, researchers have identified fractal structures of public transportation networks and land use patterns. Here, we will study spatial distribution systems for energy, fuel, medical, and food supply. It is found that these systems show power-law scaling as well, when the number of “supply stations” is plotted over the population size. Surprisingly, only some supply systems display a linear scaling with population size. Others show sublinear or superlinear scaling. We suggest an interpretation regarding the kind of scaling law that is expected in dependence of the function and constraints of the respective supply system.