Natural resources are the raw materials and energy used by society, natural capital is the total stock of natural resources available, and natural income is the flow of goods and services produced by that stock. In systems terms, natural capital is a storage, while natural income is a flow.
This distinction belongs to IB ESS Subtopic 7.1, Natural resources: uses and management, and applies at both SL and HL.
| Term | Precise IB ESS meaning | Example from a forest |
|---|---|---|
| Natural resources | Raw materials and sources of energy used and consumed by society | Timber, fuelwood and medicinal plants |
| Natural capital | The stock of natural resources available on Earth | The forest ecosystem, including its trees, soil, water, organisms and stored carbon |
| Natural income | Goods and services supplied by natural capital | New timber growth, carbon sequestration, water regulation and recreation |
The relationship can be understood using a bank-account analogy. Natural capital is the principal stored in the account, while natural income is the interest it generates. Natural resources are the useful materials and energy that society obtains from this natural capital.
Sustainable management usually requires society to consume natural income without degrading the underlying natural capital. For example, harvesting timber no faster than forest regeneration may maintain the stock. By contrast, clear-cutting a forest faster than it can regenerate reduces natural capital and therefore lowers its future natural income.
A common misconception is that natural capital means only resources with a market price. This is incorrect: natural capital can have economic, ecological, cultural, aesthetic, spiritual and intrinsic value. Different environmental perspectives may therefore value the same forest differently, while environmental justice asks who receives its benefits and who bears the costs of exploitation.
Exam technique: If asked to distinguish these terms, define all three and use explicit stock-flow language. A strong response then applies one linked example, showing that overuse of natural income can deplete natural capital and undermine long-term sustainability.
