Harare has a sphere of influence that covers the whole country. Image credit harare-info.com
ZIMSEC O Level Geography Notes: Settlements:Urban sphere of influence and urban hierarchy
A sphere of influence is an area which depends on a given urban area for a particular good or service.
This area is also known as a town’s hinterland.
The type and variety of goods and services that an urban center offers depend on its size and population size.
Small centres offer a limited number of goods and services when compared to larger cities
Large towns and cities also provide specialist services in addition to providing a wider variety of goods and services to the wider population
The large populations of large cities enable them to provide higher order goods and services tha are not frequently in demand e.g. building materials
They thus have a larger sphere of influence
Small centers provide lower order goods that are frequently in demand e.g. groceries
These centres thus have smaller spheres of influence
These centres offer offer goods and services that meet people daily needs for which consumers are not prepared to travel long distances for
These goods are known as consumer goods
The larger centres in addition to providing lower order goods and services also supply goods and services that are less frequently in demand and for which people are willing to travel longer distances e.g. cars.
These goods are known as comparison goods
The Urban Hierarchy
The bigger the settlement the less they are. Image credit wordpress.com
Settlements can be described as being part of the urban hierarchy.
Where they stand on the hierarchy depends on a number of factors, the main ones being population, the number of services a settlement has and its sphere of influence.
This can be represented on a pyramid as shown above
In a given area there will be many lower order urban centers e.g. small towns such as Rusape and Zvishavane
There will be fewer middle order urban centers such as small cities like Mutare.
There will be even fewer high order urban centers for example Harare and Bulawayo