Distribution, characteristics and adaptation of three ecosystems (coniferous and rain forests and savannah grasslands)
Human activity and impact on each ecosystem.
Slash and burn
Tropical Rain Forest
What is an Ecosystem?
A community of plants and animals which interact with each other and with the non-living environment.
Living Creatures Ecosystem Links Vegetation Energy from the sun Rocks and Soil Climate
Nutrient Cycle Twigs and leaves fall to the ground and become ‘litter’ Decomposition (breaking down) of litter by termites, fungi and bacteria Nutrients enter the soil Soil is fertile Dense vegetation
What are the worlds major ecosystems (biomes)?
Coniferous forest otherwise known as: Taiga or Boreal
Reasons for distribution of Coniferous Forest
Very cold winters
Short warm summers
Low annual precipitation
Only a few types of tree (pine, spruce) can survive the cold = no biodiversity
Conical shape (flexible, bend in strong winds)
Downward sloping branches (snow slides off)
Needle leaves (Water loss by transpiration reduced)
Thick Bark (Protects from cold, sap contains anti freeze)
Evergreen (Must be ready for short growing seasons
Dig for food
Tropical Rainforest Location
Tropical Rainforest Climate
Hot all year round
Wet all year
High annual rainfall
Vegetation needs both of these
Extensive species eg mahogany and teak (massive bio diversity)
Only restriction to growth is access to sunlight
Leads to five layers
Great density of vegetation
Evergreen trees (constant growth)
Adaptations to reach sunlight
Soils - Latosols
Red in colour
However high rainfall creates similar conditions to podsols, thin humus, rapid leaching then deposition
Minerals held in large quantity of leaf litter which is rapidly recycled
Traditional Human Impact
Traditionally impact minimal
Hot, humid climate with many pests
Latosol soil soon found to be infertile on removal of vegetation
Highly specialised nomadic cultures only survived well
Modern Human Impact
Modern Human Impact Leads To DEFFORESTATION
What is Sustainable development?
What is sustainable development?
"Development that meets the needs of the present without compromising the ability of future generations to meet their own needs." - The United Nations World Commission on Environment and Development
Founded in 1995, the Liana Project coordinates the efforts of skilled people within the forest communities of the Brazilian Government’s Extractive Reserves.
By creating locally controlled micro-enterprises that use sustainably harvested vines and natural fibers to make furniture and decorative goods, the project integrates forest conservation, local economic development, and the preservation of traditional skills.
There are six aims
Improve quality of life of locals
Provide secure income for locals
Develop ways of increasing production without debt
To conserve the environment
To encourage re-use
To develop technology which is appropriate to the skills, wealth and needs of locals
Products made with amazonian fibres
You MUST know a full case study for human impact in a Tropical rainforest – recommend AMAZON
Where do we find tropical grasslands?
Climate Graph for Serengeti, Tanzania
Tall tufted grasses with the occasional tree or shrub
Close to streams and rivers cover including trees may increase
Two main layers of vegetation
Extensive animal life
Hot temps = high evaporation rates
Upward movement of water carries dissolved minerals eg calcium
Minerals deposited in upper layers = rich soil
Litter layer large especially at the start of the dry season
Decomposition rapid in wet season, much slower in dry season
Areas of bare ground
Drought Resistance – deciduous trees that lose leaves during dry season. b
Scavengers – an essential part of the food chain
Flora of tropical grasslands
How is this plant adapted to its environment?
How has this tree adapted to the climate?
Case Study: The Serengeti
The biggest threat facing tropical grasslands is desertification
What is desertification ?
Desertification is when a desert gradually spreads to the surrounding areas of semi-desert
What is desertification ?
Desertification is when a desert gradually spreads to the surrounding areas of semi-desert As tropical grassland buffers the edge of many deserts it is particularly vulnerable to desertification
What might cause desertification? Brainstorm your ideas
MEMORY MAPS Drought in the Sahel
* * * * NEWS FLASH * * * *
MONDAY 22 ND MARCH 1973
DROUGHTS HAVE PLAGUED THE LAND HERE IN THE SAHEL STRETCHING FROM WEST AFRICA EASTWARDS FOR FIVE YEARS BUT IS DROUGHT HERE REALLY THE PROBLEM?
LAND USE PRACTISES HAVE CAUSED THE DEATHS OF MORE THAN 100,000 PEOPLE
OVER 12 MILLION CATTLE HAVE DIED
SOCIAL ORGANISATIONS HAVE BEEN DISRUPTED ON A NATIONAL SCALE
The SAHEL The Sahel is located in the southern region of the Sahara desert, Africa.
The Sahel regions are areas which experience
Why does the Sahel suffer from desertification?
DESERTIFICATION Increase in population Increase in cattle Deforestation for fire wood Grassland grazed more intensively Roots no longer hold soil together Roots may be eaten as well as grass Leaves no longer protect soil from weather Less vegetation means less protection from weather Loose top soil blown away by wind (Soil Erosion) = Loose top soil blown away by wind (Soil Erosion) = DESERTIFICATION