Spatial diffusion
Also called: Diffusion of innovations, Hagerstrand model · Topic: Human Geography: Nature, Scope and Approaches · NCERT: Beyond NCERT
Meaning
Spatial diffusion is the spread of an idea, a technology or a disease across space over time. Torsten Hagerstrand of Sweden (1953) built models of how new ideas spread from person to person and place to place. Geographers describe two main types. In expansion diffusion, the trait spreads outward from its source. It can spread to nearby places (contagious), or move from big centres down to smaller ones (hierarchical). In relocation diffusion, migrants carry the trait with them to new places. Today's GIS and spatial analysis grew out of this kind of work.
Example
High-yielding Green Revolution seeds first spread across Punjab and Haryana. They then reached neighbouring western Uttar Pradesh as farmers copied nearby farmers. This is expansion diffusion.
Don't confuse with
- Migration: this is the movement of people. Relocation diffusion is the spread of a trait, such as a crop, a language or a disease, that the migrants carry with them.