Why do people live in areas at risk of tectonic hazards?

What are economic sectors?

Every job in the world fits into one of four economic sectors, based on what kind of work it involves:

• Primary sector – Jobs that involve using natural resources directly from the land or sea. This includes farming, fishing, mining, and forestry.
• Secondary sector – Jobs that involve making or building things. These are often factory-based or linked to construction.
• Tertiary sector – Jobs that provide a service. This includes everything from shop assistants and doctors to delivery drivers and teachers.
• Quaternary sector – Jobs that involve research, technology, and expert knowledge. Examples include scientists, software engineers, and data analysts.

Explaining each sector

Primary sector
This sector involves working with raw materials. Farmers grow crops or rear animals, miners dig up valuable minerals, and foresters manage woodlands for timber. These jobs are often found in rural areas and may involve hard physical work or reliance on nature.

Secondary sector
This sector takes raw materials and turns them into finished products. Think of car assembly lines, clothing factories, or house construction. These jobs are often located in towns or cities where transport and access to workers are easier.

Tertiary sector
These are service-based jobs. They can be found in various industries, including health, education, retail, banking, transportation, and entertainment. You’ll find these jobs in nearly every town and city. As countries develop, this sector usually grows rapidly.

Quaternary sector
This is the newest sector, based on innovation, knowledge, and technology. It includes scientific research, IT development, and financial services. Countries with highly developed economies often have growing numbers of people in this sector.

What is the Clark-Fisher Model?

The Clark-Fisher Model

The Clark-Fisher Model is used to show how the importance of different sectors changes as a country becomes more developed. It outlines three main stages of economic development:

1. Pre-industrial stage

• Most people work in primary jobs like farming.
• These are usually low-income, labour-intensive jobs.
• Countries at this stage are often rural and less developed.
• Examples: Afghanistan, parts of sub-Saharan Africa.

2. Industrial stage

• Rapid growth in the secondary sector occurs as factories are built and manufacturing grows.
• People move to towns and cities for better-paid factory work.
• Countries at this stage are usually classed as newly emerging economies (NEEs).
• Examples: India, Indonesia, Vietnam.

3. Post-industrial stage

• The economy shifts towards tertiary and quaternary jobs.
• Technology reduces the need for workers in farming and manufacturing.
• Most people work in services like healthcare, finance, and IT.
• Countries at this stage are highly developed.
• Examples: the UK, Japan, and the USA.

As a country develops, employment shifts from the primary to the secondary, and finally to the tertiary and quaternary sectors.

Why does employment structure change over time?

Several reasons explain why employment structures evolve:

• Technology and machinery – Fewer workers are needed in farming or factories.
• Urbanisation – People move to cities for better job opportunities in services.
• Education – More people have qualifications, opening up skilled jobs.
• Global trade – Some countries focus on services while others take on manufacturing.
• Government policies – Decisions about investment, industry, and trade affect which sectors grow.

Example: Changes in the UK

The UK has experienced a huge shift in its employment structure over time: