Topic 3: Battle for the Biosphere
What you need to know:
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How to describe the distribution of Biomes across the Earth’s surface
How climate (temperature and precipitation) influences the distribution and types of
Biomes
How local factors, such as altitude, also influences biome distribution
How the biosphere provides important services to humans
How the biosphere provides goods (resources) that humans use
How goods and services support human life on Earth
How humans are directly degrading biomes by their actions, such as deforestation
A named example of biome degradation
How global climate change is affecting biomes
Why humans need to conserve biomes and biodiversity
How to define sustainable and unsustainable
Why humans need to use biomes more sustainably in the future
How global actions and agreements could help make this possible
Examples of global actions and agreements
How local and national management could conserve biomes
Examples of local and national management
What is the Biosphere?
The biosphere is the part of the Earth’s surface that is inhabited by living things.
A biome is a large ecosystem. Climate (temperature, Rainfall and sunshine) determines what animals
and plants live in a biome.
Examples of Biomes include:
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Tropical rainforest
Deserts
Deciduous
Coniferous forest
Tundra
Biomes are different
in different parts of
the world because of
the difference in
climate.
Lines of latitude travel in rings
around the Earth. The equator
is a line of latitude
Latitude has an effect on climate so often biomes change as you travel north or south.
The Sun’s rays are more intense at the Equator leading to hotter temperatures in the Tropics.
Apart from temperature, rainfall and sunshine there are local factors which can change a biome.
Local Factors that change biomes
Distance from coast - Near the coast land is
Geology - Limestone bedrock creates dry soil
cooled by the sea, decreasing the average
conditions as it does not retain water.
temperature
Altitude - Temperature decreases by 10C for
Distance inland - Inland areas isolated from
every 100m gained in altitude.
the sea suffer from low rainfall.
Task: Describe how local factors affect the growth of rainforests (4 marks)
The biosphere life-support system
The biosphere acts as a life-support system for the planet, helping to regulate the composition
of the atmosphere, maintaining soil health and regulating the hydrological (water) cycle.
Plants absorb carbon dioxide and
produce oxygen instead
Dead leaves and plants add nutrients to
the soil. Insects and animals burrow,
helping the soil breath
Trees and other plants slow the flow of
rainwater to rivers acting as a natural
flood control
What goods and services can be provided by the Tropical Rainforest?
Goods are products which can be removed from the forest. This can be done in a sustainable way
(this means without damaging the forest). Services are things which the forest does for the
biosphere, these are usually processes that the forest helps to run that benefit life on the
planet.
Goods and their benefits
Food (berry, nut and fruit
picking or larger scale cereal
production. Wheat and corn
are increasingly used for the
production of biofuels as well
Medicines (Many
Raw materials (The biosphere
naturally occurring
provides raw materials for industrial
substances act as
activities. E.g, wood for the
medicines and
construction of houses and boats)
remedies)
as fuel)
Services and their benefits
Water control (Forests
Atmosphere
(Forests removes
Carbon dioxide
intercept rainwater on
their leaves. This slows
the water down in getting
from the
to the river. This reduces
atmosphere and
this reduces global
the risk of flash floods.
warming)
Nutrient Cycle (Leaf litter from dying plant leaves are
broken down by termites and fungi on the forest floor.
This releases nutrients into the soil to help make the soil
fertile and allow other plants to grow)
Ecotourism (natural resources for
people to enjoy in a sustainable way)
Task: Describe some of the goods and services the biosphere provides humans with (4 marks)
Task: Describe two services that the biosphere provides and explain why they are important
What is a Tropical Rainforest?
Found mostly in a band around the equator. Here the
concentrated Sun’s rays heat the moist air causing it
to rise. Heavy rainfall is the result and a climate with
near perfect all year growing conditions.
The climate graph shows a constantly high
temperature (red line) and generally very high levels
of rainfall (blue bars).
The rainforest has great biodiversity – this means it
has a great variety of different types of plants and
animals. E.g. the Amazon rainforest
What impacts are humans having on the Tropical Rainforest
Human Activity
Logging
Effects/Impact
Commercial logging destroys the forest and animal habitat. Often
several trees are destroyed in the process of cutting down and
removing one tree.
Commercial intensive farming requires massive areas of land to be
Conversion to
deforested. Either plantations of crops such as soya and coffee
farmland
are grown or the land is used for grazing cattle for beef.
Mining cuts away whole hillsides. Opencast mining destroys the
Mining
surface. Transport to and from the mine also causes pollution. Case
Study: Carajas Scheme, Amazon.
Road building
Allows access to previously inaccessible parts of the forest. This
can then lead to deforestation for logging or farming.
Population growth
Population of Brazil has increased from 60 million in the 1960s to
nearly 200 million today putting huge pressure on the Amazon, e.g.
more room for houses and farm land
Pollution and
Main threat comes from increased Carbon Dioxide. Rainforest frogs
Climate Change
have disappeared in large numbers due to temperature change.
All forms of deforestation have an impact on the processes that take place on the forest.
The removal of trees reduces the leaf litter falling onto the forest floor, which in turn will
reduce the amount of nutrients that enter the soil. This therefore reduces the soils
ability to allow new plant growth (The nutrient cycle will no longer work).
Case Study – Amazon Rainforest
Task: Describe the impacts that human activities are having on the Amazon (4 marks)
How can we sustainably mange biomes?
Sustainability – the ability to keep something going at the same rate or level. The current
generation of people should not damage the environment in ways that will threaten future
generations’ environment
Unsustainable - unable to be kept going at the same rate or level
Sustainable management means to make use of a resource in a way that:
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Protects it for future generations to enjoy.
Benefits and trains local people.
Is environmentally friendly.
To make use of the goods that the tropical rainforest provides we must sustainably manage it.
Strategy
Ecotourism
Sustainable Management Strategies
Benefits
This encourages tourists to visit a biome such as a
rainforest. However, the aim of the holiday is to
promote environmental awareness. Local people
run the resort so earn money and learn new skills.
The resorts are often small so have only a minimal
impact on the environment.
Case Study
Santa Lucia,
Tropical
Rainforest in
Ecuador.
National Parks
These are conservation areas which are set up in
valuable or rare environments. They have very
strict rules about what can be built by the
landowners and residents of the park and what
industry can take place in the park. Tourists are
encouraged to visit and learn about the area.
Peak District,
UK.
Global management:
Wetlands (area where
water is the primary
factor controlling the
environment and the
associated plant and
animal life)
Local management:
Biodiversity Action
Plans (BAPs), e.g.
Community Forests
The Ramsar Convention (a global treaty) has
achieved real success, protecting wetlands
everywhere from unsustainable over-exploitation.
Wetlands are among the world’s most ecologically
productive environments. They are also an
important source of water for people.
Severn Estuary
Together, the twelve Community Forests were able
to help to improve the health, well being and
quality of life of over half of England's population
The Community Forests have planted over 10,000
hectares of new woodland and provided sustainable
living spaces for thousands of people and animals.
Greenwood
Forrest,
Nottinghamshire
Task: Choose a local example of biosphere management. Explain the methods used to make it more
sustainable (4 marks)