Increasing Demand for Natural Resources (OCR GCSE Geography B)

Revision Note

Bridgette Barrett

Written by: Bridgette Barrett

Reviewed by: Jenna Quinn

Factors Increasing Demand

  • The demand for resources is increasing rapidly 

  • Demand is outstripping supply in many areas of the world for food, water, and energy

  • There are a number of reasons for this:

    • Population growth

    • Economic development

    • Lack of supply

Population growth

  • In 2022 the world's population increased to over 8 billion people

World population total and growth rate

Graph showing world population growth rate from 1760 to 2100 with population numbers indicated; peak at 2.1% around 1960, declining thereafter.
Graph of world population total and growth rate
  • The world population is predicted to reach 9.2 billion by 2040

  • This is a rapid increase since the early 1900s when the population was below 2 billion people

  • The more people there are, the higher the demands for food, energy, and water

Economic development

  • As countries develop, the people have increased incomes

  • This increases the demand for consumer goods, energy and water

  • Increased demand for products also leads to more industry to produce the goods, both factories and agriculture.

  • These industries also require energy and water, further increasing the demand

Lack of supply

  • Many natural resources are finite - they are being used faster than they can be replenished:

    • Fossil fuels (coal, oil, and gas)

    • Freshwater

    • Minerals such as copper, iron, 

  • Even for those resources which are not finite it may be difficult to meet the demand 

  • There is a decreasing amount of land available for food growth due to expanding settlements, the use of land for growing biofuels and desertification

Exploitation of Ecosystems

  • Environments and ecosystems are used and modified by humans 

  • The scale of this has increased as the demand for resources rises

Food supply

  • As countries develop the impact of farming systems on the environment increases

    • In LIDCs subsistence farming dominates

    • In ACs commercial farming dominates 

  • Commercial farming relies on improvements in technology to produce high yields which can be sold for profit. These technologies include:

    • Mechanisation - the use of tractors, combine harvesters

    • Artificial chemicals - pesticides, herbicides, and fertilisers

    • Greenhouses - using artificial heat and light 

  • Commercial fishing also uses improvements in technology to catch large quantities of fish

    • Trawlers use large nets which are dragged along the seabed this is called bottom trawling

    • Blast or dynamite fishing uses explosives to stun or kill large quantities of fish in an area

  • These lead to overfishing which is when so many fish are caught the fish population is unable to repopulate fast enough

Impacts of Farming Systems

  • All farming systems impact the ecosystem in which they are located

  • Some have more impact than others such as:

    • Monocultures which reduce diversity because the animals have no access to a wide range of foods

    • Soil nutrients are depleted because nutrient cycling becomes dependent on fertilisers added to the soil, this may be natural (manure) or artificial fertilisers 

    • When the ecosystem is modified with inputs of seed, fertiliser, pesticides, herbicides, and the use of machines

    • Fertilisers, pesticides, and herbicides pollute the water and soil

    • Food webs are reduced due to lower biodiversity levels

    • Removal of trees and hedgerows to create larger fields reduces the amount of biomass

    • Soil erosion increases because the soil is exposed to the wind and rain

Worked Example

Describe two ways in which the mechanisation of farming has impacted on ecosystems

(2 marks)

Answer

  • Hedges have been removed from fields so that tractors can be more easily used in fields [1].

  • (Spraying) pesticides which can kill insects [1].

  • Farms take up larger areas providing less food for wildlife/ reducing biodiversity [1].

  • The use of tractors will produce more carbon dioxide which can lead to climate change [1].

  • (Sprayed) Fertilisers can run off the fields into rivers/ lead to eutrophication [1].

  • Combine harvesters can compact soil leading to increased soil erosion [1].

  • Deforestation to create fields will reduce habitats for animals [1].

Energy supply

  • Fuelwood and fossil fuels are the main sources of energy across the world

Fuelwood - deforestation

  • It is estimated that more than between 2 and 3 billion people across the world rely on fuelwood for heating and cooking usually because they do not have access to other forms of energy

    • Approximately 13% of the world's population does not have access to electricity

    • This is mostly an issue in LIDCs within Sub-Saharan Africa and Asia

  • The use of fuelwood leads to deforestation 

  • The amount of wood cut each year is greater than the rate of replanting and regrowth

  • This impacts on ecosystems, reducing biodiversity because plants and animal habitats are destroyed

Fossil fuels - mining

  • Over 80% of the world's energy is provided by fossil fuels

  • These fuels, oil, gas, and coal, are obtained by mining and drilling

  • This leads to deforestation as areas have to be cleared for buildings and roads

  • Habitats are destroyed, which impacts the ecosystem

  • Waste material leaches into the soil and water sources, leading to soil and water pollution

Water supply

The two main ways in which the demand for water is met is via:

  • Reservoirs

  • Water transfer schemes

Reservoirs

  • Reservoirs are created to store water

  • A dam is placed across a river, and this causes the land behind the dam to flood creating the reservoir

  • Over 60% of the world's major rivers are impacted by dam construction

  • The impact of a dam and reservoir occurs both upstream and downstream

  • Upstream:

    • The flooding of the valley destroys habitats

    • The water may be polluted by any housing or industry which was located in the area flooded

    • Fish migration routes may be blocked, and fish may be disorientated

    • The depth of water reduces oxygen levels because the water is too deep for photosynthesis and the mixing of air and water at the surface

    • The lack of oxygen reduces the biodiversity 

  • Downstream

    • Water lacking oxygen enters the river, this can affect fish and other wildlife

    • Sediment is trapped by the dam, which means less sediment is deposited downstream which affects the fertility of the floodplain and the supply of sediment to deltas

Water transfer schemes

  • Water transfer schemes are found in many parts of the world 

  • Water is transferred from one area to another using pipes, canals, and rivers 

  • This can affect the ecosystems in both areas. Impacts include:

    • Over-abstraction of water from the donor area which reduces the availability of water in that ecosystem

    • Water pollution may spread over a greater area

    • Ecosystems and food webs may be disrupted 

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Bridgette Barrett

Author: Bridgette Barrett

Expertise: Geography Lead

After graduating with a degree in Geography, Bridgette completed a PGCE over 25 years ago. She later gained an MA Learning, Technology and Education from the University of Nottingham focussing on online learning. At a time when the study of geography has never been more important, Bridgette is passionate about creating content which supports students in achieving their potential in geography and builds their confidence.

Jenna Quinn

Author: Jenna Quinn

Expertise: Head of New Subjects

Jenna studied at Cardiff University before training to become a science teacher at the University of Bath specialising in Biology (although she loves teaching all three sciences at GCSE level!). Teaching is her passion, and with 10 years experience teaching across a wide range of specifications – from GCSE and A Level Biology in the UK to IGCSE and IB Biology internationally – she knows what is required to pass those Biology exams.