The Living World

HideShow resource information


Comprises plants (flora) and animals (fauna)
Non-living components include:
 the climate
--> soil
--> light

Different scales:
-->local ecosystems (ponds, a hedge)
-->larger ecosystems (lakes, woodlands)
-->global ecosystems (tropical rainforests, deciduous woodland)

1 of 24

Ecosystems: KEY TERMS

  • Ecosystem: The living and non-living components of the environment and the interrelationships that can exist between them
  • Biomes: Global-scale ecosystems
  • Adaptations: The ways that plants evolve to cope with certain environmental conditions such as excessive rainfall
  • Producers: Organisms that obtain their energy from a primary source (sun)
  • Consumers: Organisms that obtain their energy by eating other organisms
  • Food chain: A line of linkages between producers and consumers
  • Food web: A diagram that shows all the linkages between producers and consumers in an ecosystem
  • Scavengers: Organisms that consume dead plants or animals
  • Decomposers: Organisms such as bacteria that break down plant and animal material
  • Nutrient cycling: The recycling of nutrients between living organisms and the environment
2 of 24

CASE STUDY- The freshwater pond ecosystem

Provides a variety of habitats for plants and animals
Different amounts of light, water & oxygen available in different parts of a pond
Animals living at the bottom need different adaptations to those on the margins
Some plants tolerate total immersion by sending their flowering stems to the surface of the water
Producers: convert their energy from the environment (e.g. sunlight) into sugars
                  producer- grass at the margin of the pond (reeds, marsh marigold)
Consumers: obtain their energy from the sugars made by the producers
                    consumer- a pond snail
Scavengers and decomposers: break down dead plant and animal material
                                                  scavenger- rat-tailed maggot
                                                  decomposer- bacteria
Nutrient cycle: (foods that are used by plants or animals to grow, i.e. nitrogen,
                       2 main sources: rainwater- washes chemicals out of atmosphere
                                                 weathered rock- releases nutrients into the soil
                       when plants or animals die, scavengers and decomposers recyle
                       the nutrients, making them available again for the growth of
                       plants or animals

3 of 24


The impact of change on the freshwater pond ecosystem:
Diversity and relative numbers of components can change over time
can be caused by environmental change or human-induced change
Change often has an impact on other parts of the ecosystem
Effects on the food chain if a new animal is introduced or if others become extinct

Pond margin- plenty of oxygen and light. Shelter for the insects/animals to
                         eat and
Above pond surface- birds and animals breathe oxygen
Pond surface- there is plenty of light and oxygen. Animals breathe through
gills, lungs or skins
Mid water- animals breathe through their gills or skin. Fish are the main
Food on surface or bottom of pond
Pond bottom- little oxygen or light. Plenty of shelter and food. Where
and scavengers live

4 of 24

Global ecosystems

The distribution of global ecosystems:
-Biome in the UK is temperate decidious forest

5 of 24

Temperate deciduous forests

Found across north-west Europe, eastern North America and parts of East Asia
Well suited to the moderate climate
Rainfall is distributed evenly throughout the year
Summers are warm, winters are cool
Long growing season lasting up to 7 months
Soils tend to be rich and fertile (common is a brown soil)
Weathering is active- provides nutrients
Annual leaf fall- provides organic matter to enrich the soil further
Trees shed their leaves in the winter- enables them to conserve water, in response to shortage of light and heat
Trees are broad leaved- water loss through the stomata
Rich in diversity of vegetation, large range of habitats
Layering of woodland:
The top of the fully grown trees provides a canopy
Beneath is the sub-canopy -saplings and smallers trees
Herb layer-brambles, bracken etc
Ground layer-close to the soil surface, damp and dark, ideal conditions for moss
Temperate deciduous forest: forests comprising broad-leaved trees that drop their leaves in the autumn

6 of 24

Tropical rainforests

Found in a broad belt through the tropics
Lots of rainfall, high temperatures
Ideal conditions for plant growth
Extremely lush and dense vegetation
Clear stratification
Most animals are found in the canopy- maximum light
Soils are infertile- most of the nutrients are found at the surface (dead leaves decompose quickly)
Many plants and tree have shallow roots- to absorb the nutrients
Emergents- Fast-growing trees that out-compete other trees to reach the sunlight
Many leaves have flexible bases to turn to face the sun
Many leaves have a 'drip tip' so the heavy rain can drip off
Thin, smooth bark on the trees allows water to flow down easily
Buttresses- massive ridges which help support the base of tall trees and help transport water
Lianas- woody creepers rooted the ground but carried by trees into the canopy where they have their leaves and flowers
Epiphytes- plants which can live on branches high in the canopy to seek sunlight

7 of 24

Tropical rainforests- KEY TERMS

  • Stratification: layering of forests, particularly evident in temperate deciduous forests and tropical rainforests
  • Tropical rainforests: the natural vegetation found in the tropics, well suited to the high temperatures and heavy rainfall associated with these latitudes
  • Leaching: the dissolving and removal of nutrients from the soil, typically very effective in tropical rainforests on account of the heavy rainfall (leaves behind an infertile soil- latosol)
8 of 24

Hot deserts

Hot deserts are generally found in dry continental interiors in a belt at approximately 30degrees north and 30degrees south
This is where air that has risen at the Equator descends
This forms a persistent belt of high pressure (anticyclone)
--lack of cloud and rain and high daytime temperatures (nightime temperatures plummet because of lack of cloud cover)

Desert soils- sandy or stony, little organic matter
                     dry but can soak up water rapidly after rainfall
                     not very fertile
                     evaporation draws salts to the surface (leaving
                     a white residue on
the ground)

9 of 24

Hot desert- KEY TERMS

  • Arid: dry conditions typically associated with deserts
  • Hot deserts: regions of the world with rainfall less than 250mm per year
10 of 24

CASE STUDY- What temperature deciduous woodlands a

Epping Forest, Essex
An ancient deciduous forest that runs north-east of London
A few other natural environments there- grasslands and marshes
Early uses and management: hunting deer, grazing animals, collecting firewood
the Epping Forest Act of Parliament-- the Conservators shall at all times keep Epping Forst unenclosed and unbuilt on as an open space for recreation and the enjoyment of the people' (1878)
Recent management:
-appropriate car parks, toilets and refreshment facilities and by maintaining footpaths
-providing three easy-access parks to allow access for people with disabilities
-allowing old trees to die and collapse naturally unless they are dangerous
-controlling some forms of recreation which may damage or affect other forms
-preserving ancient trees by re-pollarding them to enable new shoots to grow
-encouraging grazing to maintain the grassland and the flora and fauna
-preserving ancient earthworks and buildings
-maintaining ponds to prevent them silting up
-preserving the herd of fallow deer

11 of 24

Deforestation in Malaysia

Most of the country was covered by primary (virgin) rainforest
Most of this has gone now
One of the best rainforest protection policies in the region
--However, there may be illegal logging occuring
The rate of deforestation in Malaysia is increasing extremely fast because...
Clear felling- lead to the total destruction of forest habitats
Selective longing- less damaging, but reduces biodiversity
Requires road construction
Threatens indigenous tribes
The Bakun Dam project will results in the flooding of huge are of forest
To supply hydroelectric power
Forest will have to be cut down, indigenous people forced to move
Widespread, areas of rainforest cleared for mining operations and roads
Mining activities lead to the pollution of land
Drilling for oil and gas has begun

12 of 24

Deforestation in Malaysia cont.

Malaysia is a major producer of palm oil and rubber
Synthetic rubber has reduced rubber exports
Rubber plantations have been converted to palm oil or abandoned
Deforestation for palm oil is taking place in Borneo
Threatening many species e.g. orang-utans
Poor urban dwellers encouraged to move into the countryside
Lots of the forest was felled to make room for settlements
Very common
Some natural
'Slash and burn' can result in wildfires
Forest clearance

13 of 24

Deforestation in Malaysia- KEY TERMS

  • Primary (virgin) rainforest: rainforest that represents the natural vegetation in the region unaffected by the actions of people
  • Deforestation: the cutting down and removal of forest
  • Clear felling: absolute clearance of all trees from an area
  • Selective logging: the cutting down of slected trees, leaving most of the trees intact
  • Slash and burn: a form of subsistence farming practised in tropical rainforests involving selective felling of trees and clearance of land by burning to enable food crops to be planted
  • Selective management system: a form of sustainable forestry management adopted in Malaysia
14 of 24

Sustainable rainforest management in Malaysia

National Forest Policy
-develop timber processing to increase profitability of the exported wood and reduce demand for raw timber. the export of low-value raw logs is banned in most of Malaysia
-encourage alternative timber sources
-increase public awareness of forests
-increase research into forestry
-involve local communities in forest projects
-a new approach to forest management (the Selective Management System)
Permanent Forest Estates and National Parks
-protected areas
-however, large areas are used for commercial logging
-some of the land has special conservation status
Forest Stewardship Council
-international organisation
-promotes sustainable forestry
-tries to educate manufacturers and consumers about the need to buy wood from sustainable resources
-aims to reduce demand for rare and valuable tropical hardwoods

15 of 24

Sustainable rainforest management in Malaysia cont

Developing tourism
-promote forests as destinations for ecotourism
-without causing environmental damage
-enables the undisturbed natural environment to create a source of income for locals without it being damaged/destroyed
Recent worldwide intitiatives
-paying countries to maintain them--debt relief
-carbon sinks--in Sierra Leone, for example, the Gola Forest was made a National Park. it is supported by money from the European Commission, the French government and non-governmental organisations, in, recognition of the forest's role in reducing global warming by acting as a carbon sink

16 of 24

Sustainable management- KEY TERMS

  • Ecotourism: nature tourism usually involving small groups, with minimal impact on the environment
  • Debt relief: many poorer countries are in debt, having borrowed money from developed countries to support their economic development. There is strong international pressure for the developed countries to clear these debts- this is debt relief
  • Carbon sink: forests are carbon sinks because trees absorb carbon dioxide from the atmosphere. They help to address the problem of global carbon emissions
  • Non-governmental organisation (NGO): an organisation that collects money and distributes it to needy causes, e.g. Water Aid, Oxfam
17 of 24

CASE STUDY- The Thar Desert, Rajasthan, India

Sandy hills with extensive mobile sand dunes and clumps of thorn forest vegetation, a mixture of small trees, shrubs and grasses
Low rainfall- soils are sandy and not very fertile
They drain quickly- little surface water
Subsistence farming
-keeping a few animals on the grassy areas
-cultivating vegetables and fruit trees
-hunting animals
-gathering fruit and natural products such as honey

18 of 24

CASE STUDY- The Thar Desert, Rajasthan, India cont

-the Indira Gandhi Canal (also provides drinking water)
-commercial farming now flourishes in previous scrub desert area
Mining and industry
-state of Rajasthan is rich in minerals
-deserts has valuable reserves of gyspum, feldspar, phospherite and kaolin
-lots of other resources such as limestone and rock marble
-local hide and wool indurstries from the livestock
-popular tourist destination
-locals benefit by acting as guides or
-by rearing and looking after camels for desert safaris

19 of 24

CASE STUDY- The Thar Desert, Rajasthan, India cont

Population pressure
-the most densely populated desert in the world
-extra pressure on the fragil desert ecosystem
-is leading to overgrazing and overcultivation
Water management
-excessive irrigation has led to waterlogging of the ground
-salts poisonous to plants have been deposited on the ground surface
-excessive demand for water has caused an unsustainable fall in water tables
Soil erosion
-overcultivation and overgrazing have damaged the vegetation in places
-leads to soil erosion

-reserves of firewood are dwindling
-people are using manure as fuel instead of improving the quality of soil

-environment will suffer if tourism becomes overdeveloped

20 of 24

CASE STUDY- The Thar Desert, Rajasthan, India cont

-Desert Development Programme
-to restore the ecological balance of the region by conserving, developing and harnessing land, water, livestock and human resources
-scientists have developed a hardy breed of plum tree
-produces large fruit
-can survive in low rainfall conditions
-potential to make a decent profit from fruit
-sand dunes are very mobile
-planting blocks of trees to stabilise them
-establishing shelterbelts of trees and fences alongside roads and canals as well
-to protect 3,000km squared of the land
-to protect the endangered and rare wildlife

21 of 24

CASE STUDY- Thar desert, Rajasthan, India KEY TERM

  • Subsistence farming: farming to produce food for the farmer and his/her family
  • Hunter-gatherers: people who carry out a basic form of subsistence farm involving hunting animals and gathering fruit and nuts
  • Commercial farming: farming with the intention of making a profit by selling crops and/or livestock
  • Salinisation: the deposition of solid salts on the ground surface following the evaporation of water
22 of 24

CASE STUDY- The Sonoran Desert. Arizona, USA

Physical extremes of the climate can be overcome by:
-using air conditioning
-irrigating crops
-short-term holiday makers and long-term migrants, retirement migration
Marana: the tale of one town in the Sonoran Desert:
-has been developed into a thriving business town and leisure resort
-irrigation system enabled it to become an agricultural centre
-since the 1990s, farming has declined to be replace with housing developments
-a heritage park has been opened
-migration accounts for the growth of Marana

23 of 24

CASE STUDY- The Sonoran Desert. Arizona, USA cont.

Managing the Sonoran Desert:
-the Sonoran Desert Conservation Plan
-to conserve the county's most valued natural and cultural resources
-detailed mapping and inventory of the county's natural and cultural heritage
-development of buffer zones around areas of ecological significance
-native plant protection
-hillside development restrictions
-home design recommendations to conserve energy and


  • Retirement migration: migration to an area for retirement
24 of 24


No comments have yet been made

Similar Geography resources:

See all Geography resources »See all Development resources »