What Is a Resource?

A resource is something that organisms or humans use to meet a need.

Natural resources come from the environment and include:

• Water.
• Soil.
• Forests.
• Wildlife.
• Fish.
• Minerals.
• Metals.
• Fossil fuels.
• Sunlight.
• Wind.

Humans depend on natural resources for food, energy, transportation, buildings, technology, clothing, medicines, and many other needs.

How these resources are obtained and used can have major effects on ecosystems and biodiversity.

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Renewable and Non-Renewable Resources

Natural resources can be broadly classified as renewable or non-renewable.

A renewable resource can be naturally replenished on a timescale that allows continued use, provided it is not consumed faster than it can recover.

A non-renewable resource forms so slowly, or exists in such limited quantities, that it cannot be replaced on a human timescale once it is used.

The distinction depends partly on the rate of use compared with the rate of replacement.

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Renewable Resources

Examples of renewable resources include:

• Sunlight.
• Wind.
• Flowing water.
• Forest products, when forests regenerate.
• Fish populations, when harvesting remains within their capacity to reproduce.
• Fresh water, when supplies are naturally replenished.

However, renewable does not mean unlimited.

A renewable resource can still be depleted if it is used too quickly.

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Renewable Does Not Mean Infinite

Imagine a forest grows enough new timber to replace approximately 2% of its usable wood each year.

If humans remove 1% each year, the forest may be able to replace what is harvested.

If humans remove 10% every year, harvesting may exceed regeneration.

The forest is renewable, but the rate of use is unsustainable.

The same principle applies to many biological resources.

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Non-Renewable Resources

Examples of non-renewable resources include:

• Coal.
• Oil.
• Natural gas.
• Metal ores.
• Many mineral deposits.

Fossil fuels formed through geological processes occurring over millions of years.

Humans consume them much faster than they are naturally produced.

For practical purposes, they are therefore non-renewable.

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Resources Can Be Difficult to Classify

Not every resource fits perfectly into one category.

Fresh water, for example, is continuously recycled through the water cycle.

However, groundwater can sometimes be removed from an aquifer faster than it is replenished.

In this situation, the water supply behaves like a limited resource.

Similarly:

Trees are renewable — forests can still disappear.

Fish are renewable — fish populations can still collapse.

The important question is:

How quickly is the resource being used compared with how quickly it can recover?

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What Is Sustainability?

Sustainability means meeting present needs while maintaining environmental systems and resources so that future generations can also meet their needs.

Sustainable resource use aims to balance:

• Human needs.
• Resource availability.
• Ecosystem health.
• Economic activity.
• Long-term resource supply.

Sustainability does not necessarily mean never using a resource.

It means considering whether the way the resource is being used can continue over the long term.

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Sustainable Yield

For renewable biological resources, an important concept is sustainable yield.

A sustainable yield is a level of harvesting that can continue without causing long-term population decline.

Imagine a fish population produces approximately 20,000 additional fish each year.

If harvesting removes:

10,000 fish per year → population may remain sustainable.

20,000 fish per year → potentially near the replacement rate.

40,000 fish per year → population may decline.

Real populations are more complicated because reproduction varies with age, population size, food supply, environmental conditions, and other factors.

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Resource Consumption

Resource consumption describes the amount of resources used by individuals, communities, industries, or countries.

Consumption varies greatly depending on:

• Population.
• Income.
• Technology.
• Lifestyle.
• Industrial development.
• Climate.
• Transportation systems.
• Energy sources.

Two populations of the same size can therefore have very different environmental impacts.

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Population and Consumption

Environmental impact is influenced by more than population size.

Consider two communities, each containing 100,000 people.

Community A may use:

• Large amounts of energy.
• Many private vehicles.
• Large quantities of manufactured products.

Community B may consume fewer materials and less energy per person.

Their total environmental impacts may therefore be very different.

When analyzing resource use, both population and consumption per person matter.

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Patterns of Consumption

Resource consumption is not evenly distributed.

Some societies use much more:

• Energy.
• Water.
• Metals.
• Manufactured goods.
• Transportation fuel.

per person than others.

Consumption patterns can also change as economies, technologies, and populations develop.

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Ecological Footprint

An ecological footprint is one way of estimating the demand that a person or population places on biologically productive land and water.

It can include demands associated with:

• Food.
• Energy.
• Housing.
• Transportation.
• Goods.
• Waste.

The concept helps illustrate that consumption has environmental consequences beyond the immediate place where products are used.

For example, a product purchased in one country may contain materials mined, grown, manufactured, and transported through several other countries.

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Environmental Impacts of Resource Extraction

Before resources can be used, many must first be extracted.

Examples include:

• Mining minerals.
• Cutting timber.
• Pumping oil.
• Extracting natural gas.
• Catching fish.
• Removing groundwater.

Extraction can affect ecosystems through:

• Habitat destruction.
• Habitat fragmentation.
• Pollution.
• Soil erosion.
• Water use.
• Noise.
• Changes to landscapes.

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Mining

Mining provides materials needed for:

• Buildings.
• Electronics.
• Vehicles.
• Electrical wiring.
• Batteries.
• Renewable-energy technologies.

However, mining can cause environmental impacts.

These may include:

• Habitat destruction.
• Soil removal.
• Water contamination.
• Waste rock.
• Dust.
• Energy use.

The environmental impact depends on the mineral, mining method, location, and management practices.

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Fossil Fuel Extraction

Coal, oil, and natural gas are important energy resources.

Their extraction can involve:

• Mining.
• Drilling.
• Pipelines.
• Processing facilities.

Potential environmental effects include:

• Habitat disturbance.
• Water contamination.
• Oil spills.
• Methane leakage.
• Air pollution.

Burning fossil fuels also releases carbon dioxide, contributing to climate change.

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Forestry

Forests provide:

• Timber.
• Paper.
• Fuel.
• Medicines.
• Food.
• Other materials.

They also provide ecosystem services such as:

• Carbon storage.
• Soil protection.
• Water regulation.
• Wildlife habitat.

Poorly managed logging can cause:

• Habitat loss.
• Fragmentation.
• Soil erosion.
• Reduced biodiversity.
• Changes in water cycles.

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Sustainable Forestry

Sustainable forest management can include:

• Harvesting trees at rates that allow regeneration.
• Protecting important habitats.
• Maintaining a mixture of tree species.
• Protecting soils and waterways.
• Replanting where appropriate.
• Allowing natural regeneration.
• Limiting road construction.
• Maintaining wildlife corridors.

The goal is to obtain forest products while maintaining the forest's long-term ecological functions.

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Fisheries

Fish are renewable biological resources.

However, populations can decline if fish are removed faster than they reproduce.

Overfishing occurs when harvesting exceeds the population's ability to recover.

Overfishing can:

• Reduce fish populations.
• Change food webs.
• Affect predators.
• Damage fishing communities.
• Reduce future catches.

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Sustainable Fisheries

Management strategies can include:

• Catch limits.
• Minimum catch sizes.
• Seasonal closures.
• Marine protected areas.
• Protection of breeding grounds.
• Restrictions on fishing equipment.
• Monitoring populations.

The goal is to allow enough individuals to survive and reproduce.

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Worked Example: Minimum Fish Size

Suppose a fish species normally begins reproducing at a length of 30 cm.

If fishermen regularly catch fish at 20 cm, many individuals are removed before they reproduce.

A minimum catch size of 35 cm could allow more fish to reproduce before being harvested.

This demonstrates how understanding a species' life history can improve resource management.

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Fresh Water

Fresh water is essential for:

• Drinking.
• Agriculture.
• Industry.
• Sanitation.
• Energy production.
• Ecosystems.

Although water moves through the water cycle, usable freshwater supplies are limited.

Water shortages can occur when demand exceeds the available supply.

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Groundwater

Water stored underground is called groundwater.

Groundwater is often stored in permeable rock formations called aquifers.

Rainwater can replenish aquifers, but recharge may be slow.

If:

Water extraction > groundwater recharge

then the water table may fall.

This can eventually make wells unusable and reduce water available to ecosystems.

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Sustainable Water Management

Strategies can include:

• Reducing leaks.
• Efficient irrigation.
• Water-efficient appliances.
• Recycling wastewater.
• Protecting watersheds.
• Collecting rainwater.
• Reducing water pollution.
• Monitoring groundwater extraction.

Different strategies are appropriate in different climates and communities.

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Agriculture and Resources

Agriculture requires major quantities of:

• Land.
• Water.
• Energy.
• Fertilizers.
• Soil nutrients.

Unsustainable farming can contribute to:

• Soil erosion.
• Habitat destruction.
• Water pollution.
• Biodiversity loss.
• Depletion of water supplies.

Sustainable agriculture attempts to maintain food production while reducing these environmental impacts.

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Soil as a Resource

Healthy soil is an extremely important resource.

Soil supports:

• Agriculture.
• Plant growth.
• Nutrient cycling.
• Water storage.
• Large communities of organisms.

However, fertile soil can take very long periods to develop.

Soil erosion can remove fertile topsoil much faster than it forms.

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Protecting Soil

Sustainable soil management can include:

• Maintaining vegetation cover.
• Crop rotation.
• Reducing excessive tillage.
• Terracing slopes.
• Windbreaks.
• Adding organic matter.
• Preventing overgrazing.

These practices can reduce erosion and help maintain soil fertility.

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Energy Resources

Energy resources can be renewable or non-renewable.

Non-renewable energy resources include:

• Coal.
• Oil.
• Natural gas.

Renewable energy resources include:

• Solar.
• Wind.
• Hydroelectric.
• Geothermal.

Energy sources should be compared using several factors rather than simply whether they are renewable.

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Evaluating Energy Resources

Useful factors include:

• Greenhouse gas emissions.
• Air pollution.
• Land use.
• Reliability.
• Cost.
• Resource availability.
• Waste production.
• Effects on ecosystems.
• Materials required.
• Energy storage needs.

A renewable resource is not automatically environmentally harmless.

For example, a hydroelectric dam produces renewable electricity but can significantly alter river ecosystems.

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Life-Cycle Thinking

Products can cause environmental impacts at several stages.

Consider a mobile phone.

Its life cycle includes:

Raw material extraction

→ manufacturing

→ transportation

→ use

→ disposal or recycling

Mining is required for metals.

Manufacturing requires energy.

Transportation requires energy.

At the end of its useful life, the phone may become electronic waste.

A life-cycle assessment examines impacts across these different stages.

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The Linear Economy

A traditional pattern of resource use can be represented as:

Extract → manufacture → use → discard

This is sometimes called a linear economy.

Resources continually enter the system and waste continually leaves it.

This can increase:

• Resource depletion.
• Pollution.
• Waste.
• Habitat destruction.

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The Circular Economy

A circular economy attempts to keep materials in use for longer.

A simplified model is:

Design → use → repair → reuse → remanufacture → recycle

The goal is to reduce both resource extraction and waste.

Perfect circularity is difficult because some materials are lost or degraded during use and recycling, but greater material recovery can reduce demand for new resources.

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Reduce, Reuse, Repair, Recycle

Waste-management strategies can be considered as a hierarchy.

Reduce

Use fewer unnecessary materials.

Reuse

Use an item again instead of replacing it.

Repair

Extend the useful life of products.

Recycle

Recover materials for use in new products.

In many situations, reducing unnecessary consumption has a greater effect than recycling the resulting waste.

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Recycling

Recycling can reduce demand for newly extracted materials.

Materials commonly recycled include:

• Metals.
• Glass.
• Paper.
• Some plastics.

However, recycling also requires:

• Collection.
• Transportation.
• Sorting.
• Processing.
• Energy.

Some materials are much easier to recycle effectively than others.

Recycling is therefore useful but is not a complete solution to resource consumption.

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Worked Example: Aluminum

Producing aluminum from mined ore requires substantial processing and energy.

Recycling existing aluminum allows the metal to be used again and generally requires considerably less energy than producing new aluminum from raw ore.

This provides two benefits:

Less mining

and

less energy required for material production.

This demonstrates how recycling can reduce pressure on both material and energy resources.

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Resource Efficiency

Resource efficiency means obtaining more useful output from a given amount of resources.

Examples include:

• Buildings requiring less energy.
• Vehicles requiring less energy per kilometer.
• Irrigation systems using less water.
• Manufacturing producing less waste.
• Products designed to last longer.

Increasing efficiency can reduce resource demand.

However, efficiency works best when total consumption is also considered.

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The Rebound Effect

Sometimes increased efficiency makes a resource cheaper or easier to use, which can encourage greater consumption.

For example:

A vehicle becomes more fuel-efficient.

→ driving becomes cheaper.

→ people may drive farther.

→ some of the expected fuel savings are lost.

This is called the rebound effect.

It shows why technological efficiency alone does not always reduce total resource use as much as expected.

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Ecosystem Services as Resources

Humans also depend on natural processes that may not be bought or sold directly.

These ecosystem services include:

• Pollination.
• Water purification.
• Soil formation.
• Carbon storage.
• Flood regulation.
• Nutrient cycling.
• Coastal protection.

Destroying ecosystems can therefore remove valuable services even if no immediate financial cost is visible.

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The Tragedy of the Commons

Some resources are shared by many users.

Examples can include:

• Fisheries.
• Groundwater.
• Grazing land.
• The atmosphere.

If each user attempts to maximize personal use, the shared resource may become depleted.

This problem is often called the tragedy of the commons.

For example:

Each fishing boat benefits from catching more fish.

But if every boat catches as much as possible:

Total harvesting > population replacement

→ fish population declines

→ eventually everyone has fewer fish available.

Management and cooperation can help prevent this outcome.

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Resource Management

Resource management involves planning how resources are used, protected, and replenished.

Effective management can involve:

• Scientific monitoring.
• Harvest limits.
• Protected areas.
• Regulations.
• Restoration.
• Recycling.
• Efficiency improvements.
• Community involvement.
• Long-term planning.

The appropriate strategy depends on the resource.

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Monitoring Resources

Sustainable management requires information.

Scientists may measure:

• Fish population sizes.
• Forest cover.
• Groundwater levels.
• Soil quality.
• Water quality.
• Wildlife populations.
• Rates of resource extraction.

Without monitoring, it is difficult to know whether use is sustainable.

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Adaptive Management

Environmental conditions change, and scientific understanding improves.

Adaptive management means adjusting resource-management strategies when new evidence becomes available.

The process can be represented as:

Plan → manage → monitor → evaluate → adjust

For example:

A fish catch limit is established.

→ fish populations are monitored.

→ population continues declining.

→ catch limit is reduced.

→ population is monitored again.

Management therefore becomes an ongoing scientific process.

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Worked Example: Forest Management

Imagine a forest produces approximately 5,000 tonnes of new usable wood each year.

A company harvests 8,000 tonnes each year.

Initially, the forest may still appear large.

However:

Harvesting > regeneration

→ forest biomass decreases

→ habitat declines

→ future timber supply decreases.

Reducing harvest below the long-term regeneration rate could make the resource more sustainable.

But managers would also need to consider biodiversity, soil, water, and forest structure.

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Worked Example: Groundwater

A farming region removes:

50 million m³ of groundwater each year.

The aquifer naturally receives:

30 million m³ each year.

The annual difference is:

50 million − 30 million = 20 million m³.

The groundwater reserve is therefore decreasing by approximately 20 million m³ per year, assuming other flows remain unchanged.

Possible solutions include:

• More efficient irrigation.
• Lower extraction.
• Different crops.
• Wastewater reuse.
• Managed groundwater recharge.

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Sustainable Development

Sustainable development attempts to improve human well-being while maintaining environmental systems and resources over the long term.

It involves considering three broad dimensions:

• Environmental sustainability.
• Economic needs.
• Social needs.

A solution that protects the environment but cannot realistically be maintained socially or economically may be difficult to sustain.

Likewise, economic development that destroys the resources supporting future development is not sustainable.

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Evaluating a Resource-Use Decision

When evaluating resource use, ask:

Is the resource renewable or non-renewable?

How quickly is it being used?

How quickly can it recover?

What environmental damage occurs during extraction?

What pollution occurs during use?

What happens when the product becomes waste?

Can materials be reused or recycled?

What alternatives exist?

What are the long-term consequences?

This provides a more complete analysis than simply labeling a resource "good" or "bad."

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Designing a Sustainable Resource Plan

Suppose a community is using a resource faster than it can recover.

A strong management plan might follow:

Measure current resource availability

→ measure consumption

→ determine sustainable limits

→ reduce unnecessary use

→ improve efficiency

→ reuse or recycle where possible

→ protect the ecosystem supplying the resource

→ monitor the results

→ adjust management when necessary.

Sustainability requires both scientific evidence and long-term planning.

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Common Mistakes

Thinking Renewable Means Unlimited

Renewable resources can be depleted when use exceeds their rate of replacement.

Thinking Non-Renewable Means It Cannot Be Recycled

A metal ore is non-renewable, but the metal extracted from it may be recyclable.

Assuming All Renewable Energy Has No Environmental Impact

Renewable-energy technologies require land, materials, infrastructure, and manufacturing and can affect ecosystems.

Thinking Sustainability Means Never Using Natural Resources

Sustainability focuses on using resources in ways that can continue without unacceptable long-term environmental damage.

Assuming Recycling Is Always the Best First Option

Reducing unnecessary use and extending product life can sometimes prevent more resource use than recycling.

Ignoring Consumption Per Person

Environmental impact depends on both population and consumption patterns.

Looking Only at the Use Stage of a Product

Extraction, manufacturing, transportation, use, and disposal can all create environmental impacts.

Assuming More Efficient Technology Automatically Reduces Total Consumption

The rebound effect can reduce some of the expected savings.

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Check Your Understanding

1. Define a natural resource.

2. Distinguish between renewable and non-renewable resources.

3. Give four examples of renewable resources.

4. Give four examples of non-renewable resources.

5. Explain why a forest can be renewable but still be used unsustainably.

6. Define sustainability.

7. What is meant by sustainable yield?

8. Explain why population size alone does not determine resource consumption.

9. Describe three environmental impacts of mining.

10. Explain how overfishing can reduce future fish catches.

11. Why can groundwater sometimes be used unsustainably even though water is renewable?

12. Describe two sustainable forestry practices.

13. Explain how soil erosion threatens an important natural resource.

14. Compare a linear economy with a circular economy.

15. Why can repairing a product sometimes be more sustainable than replacing and recycling it?

16. Explain the rebound effect.

17. What is the tragedy of the commons?

18. Explain why monitoring is necessary for sustainable resource management.

19. A forest regenerates 6,000 tonnes of usable wood per year while 9,000 tonnes are harvested. Explain why this is unsustainable and propose a solution.

20. A community is extracting groundwater faster than its aquifer is recharging. Propose three strategies that could make its water use more sustainable.

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Key Terms

• Resource – something used to meet a need.
• Natural resource – useful material or process obtained from the natural environment.
• Renewable resource – resource that can naturally replenish on a useful timescale.
• Non-renewable resource – resource that cannot be replaced on a human timescale at the rate it is consumed.
• Sustainability – use and management of resources in ways that maintain their availability and environmental systems over the long term.
• Sustainable yield – level of harvesting that can continue without causing long-term population decline.
• Resource consumption – use of materials, energy, water, and other resources.
• Ecological footprint – estimate of the environmental demand created by an individual or population.
• Overfishing – removal of fish faster than populations can recover.
• Aquifer – underground layer capable of storing and transmitting groundwater.
• Resource efficiency – obtaining greater useful output from a given quantity of resources.
• Life-cycle assessment – evaluation of environmental impacts throughout a product's life.
• Linear economy – system based largely on extracting, producing, using, and discarding resources.
• Circular economy – system designed to keep materials in use through reuse, repair, remanufacturing, and recycling.
• Rebound effect – increased consumption that offsets some benefits gained from improved efficiency.
• Ecosystem services – benefits humans receive from functioning ecosystems.
• Tragedy of the commons – depletion of a shared resource when individual users have incentives to overuse it.
• Adaptive management – adjustment of management practices using monitoring and new evidence.
• Sustainable development – development that considers long-term environmental, economic, and social needs.

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Key Takeaways

• Natural resources provide the materials and energy required by human societies.
• Renewable resources can replenish, while non-renewable resources are replaced too slowly to support continued extraction indefinitely.
• Renewable does not mean unlimited.
• Sustainability depends strongly on the relationship between the rate of consumption and the rate of replacement.
• Forests, fisheries, freshwater, and soils can all be damaged by unsustainable use.
• Resource extraction can cause habitat destruction, pollution, erosion, and biodiversity loss.
• Resource consumption depends on both population and consumption per person.
• Sustainable management can involve harvest limits, habitat protection, efficient technology, recycling, restoration, and scientific monitoring.
• Products should be evaluated across their complete life cycle, from resource extraction through disposal or recycling.
• A circular economy attempts to keep materials in use longer and reduce both extraction and waste.
• Reducing unnecessary consumption, reusing products, and repairing them can decrease demand for new resources.
• Recycling can conserve resources but still requires energy and infrastructure.
• Renewable-energy technologies generally reduce dependence on fossil fuels but still have environmental impacts that should be evaluated.
• Ecosystem services such as pollination, water purification, soil formation, and flood regulation are valuable resources supplied by functioning ecosystems.
• Shared resources can be depleted when individual users take more than the system can replace.
• Monitoring is necessary to determine whether resource use is genuinely sustainable.
• Effective resource management follows the general pattern measure → manage → monitor → evaluate → adjust.