Population change and accessibility by road and rail networks: GIS and statistical approach to Finland 1970–2007

This study analyzes the relation of accessibility by road and railway network to population change between the years 1970–2007 in Finland. Accessibility is evaluated at built-up area unit and municipal levels by potential accessibility analysis and by measuring accessibility to network. Analyses are done in decadal periods by using geographical information systems (GIS) and data about road and railway networks involving digitized speed limits and geometry for each period. Accessibility variables and population change are related by generalized additive models (GAMs). The results indicate that the Finnish population has concentrated to areas with high road-based potential accessibility, especially since the opening in the Finnish economy in the 1990s. The accessibility of railway network was found to have affected the population change in the 1970s, when local level traffic reduced in the entire country, and in 2000–2007, following remarkable investments in long-haul transport.

Research highlights
► Potential accessibility strongly relates to recent population change in Finland.
► Generalized additive models (GAMs) distinctly reveal non-linear effects of accessibility.
► Railway accessibility has detectable, but minor role in explaining population change.