Datensatz

Zusammenfassung

Urban growth can take different forms, such as infill, expansion, and leapfrog development. Here we focus on
leapfrogging, which is characterised as new urban development bypassing vacant land. Analysing a sample of 100
global locations, we study the probability that land cover is converted from non-urban to urban as a function of the
minimum distance to existing urban cells. The probability decreases with the distance but in many of the considered
real-world samples it increases again just before the maximum possible distance. Comparing these empirical findings
with numerical ones from a gravitational model, we discover that the characteristic increase can be found in both. Our
results indicate that the conversion probability as a function of the distance to urban land cover includes three urban
growth domains. (i) Expansion of existing settlements, (ii) discontinuous development of coincidental new settlements
rather close to existing ones, and (iii) leapfrogging of new settlements far away from existing ones. We conclude
that gravitational effects can explain discontinuous development but leapfrogging can be attributed to a scarcity of
developable land at long distances to settlements.