Implications of Degradation of Water & Carbon Cycles (Edexcel A Level Geography)

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Louise Stone

Written by: Louise Stone

Reviewed by: Bridgette Barrett

Changes in Global Forest Coverage

Deforestation

  • An estimated 1.6 billion people depend on forests and more than 90% of these are in developing countries

  • Forests are essential for human well-being through their services as well as being the source of 80% of global biodiveristy

The Forest Ecosystem Services

Type of Service

Description

Supporting Functions

  • Nutrient cycling

  • Soil formation

  • Primary production

Provision of Goods

  • Food

  • Freshwater 

  • Wood and Fibre

  • Fuel

Regulation of Earth’s Systems

  • ‘Green lungs’, regulating climate, floods and disease

  • Water purification

Cultural Value

  • Aesthetic 

  • Spiritual 

  • Educational

  • Recreational (inc. tourism)

  • An estimated 13 million hectares of forests between 2000 and 2010 were affected by deforestation 

global-forest-cover-1
Annual Deforestation in 2016
  • However, the net loss was reduced because of afforestation 

  • The environmental Kuznets curve suggests that communities reach a tipping point where exploitation of forests changes to more protection

  • The changes in attitudes are usually dependent on:

    • The wealth of a country

    • Increasing knowledge of the role that the environment plays in our well-being

    • Aid given to developing countries to help reduce exploitation

    • Political systems and introduction and enforcement of environmental laws

    • The involvement of locals

    • The power and influence of TNCs

global-forest-cover-2
The Environmental Kuznets Curve
  • It is hoped that the sustainable management of forests will reduce deforestation and as a result reduce carbon emissions from forests

  • Currently, 18% of forests are classed as conserved

    • Brazil and the USA have the largest National Parks and Forest Reserves

  • Successful reduction of forest loss in the long term requires:

    • Protective legislation

    • Community involvement in planning and developing policies

Examiner Tips and Tricks

Make sure you are able to provide examples of the services that ecosystems (especially forests) provide that are essential for human well-being 

Effects of Increased Temperature

Effects of Increasing Temperatures

  • Global warming is increasing global temperatures which affects evaporation rates and increases the amount of water in the atmosphere

  • These changes can have impacts on the hydrological cycle, for example:

    • Precipitation patterns

    • River Regimes

    • Water Stores (cryosphere and drainage basin)

The Arctic

  • The Arctic plays an important role in global climate, as its sea ice regulates evaporation and precipitation

  • The Earth’s cryosphere has already been affected by rising temperatures, for example: 

    • Antarctica and Greenland ice sheets have lost mass and glaciers are shrinking

    • Arctic sea ice and spring snow cover in the northern hemisphere continue to decrease in extent and thickness 

  • The Arctic acts as a barometer or early warning system for the environmental impacts resulting from the burning of fossil fuels

    • Arctic temperatures have risen twice as fast as the global average in the past few decades

    • Significant loss of sea ice e.g., the North-west Passage can now be navigated in the summer

    • Permafrost is melting

    • Carbon uptake by plants is increasing because of the lengthening of their growing season

    • A loss of albedo as the ice that once covered the land is replaced by tundra and tundra is replaced by taiga (further encouraging global warming)

Threats to Ocean Health & Implications for Humans

Ocean Health and Impacts on Huma Well-being

  • Global warming is affecting ocean temperatures and currents as well as the supply of nutrients and marine food chains

  • These changes can be categorised under the following:

    • Bleaching

    • Acidification 

    • Rising sea levels

    • Loss of sea ice

  • These changes then have an impact on distribution, abundance, breeding cycles and migration of marine plants and animals which millions of people depend on either directly or indirectly for food and income

  • Research suggests that marine organisms may be responding faster to climate change than terrestrial organisms

ocean-health
Importance of Ocean Health

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Louise Stone

Author: Louise Stone

Expertise: Geography

Louise graduated with a degree in Geography with Natural Hazards before doing her PGCE and Masters degree with the University of Birmingham. Teaching is her passion and has taught across different specifications at GCSE and A-Level. Louise has also been an examiner for two exam boards for 9 years now to gain a deeper insight into the different exams and expectations of students. Louise enjoys creating content to help students fulfil their potential in Geography.

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.