How does the biosphere support life on earth?

Aim:

To understand the interdependence between ecosystems and people.

• http://www.bbc.co.uk/learningzone/clips/rainforest-processes-costa-rica/3091.html watch this clip and answer the questions in notes at the back of your bookWhere do you find rainforests?What distinguishes them from other forests?What’s the average annual rainfall?How does the rainforest return moisture to the atmosphere after rainfall? (2 ways)How much of the rainfall is transpired back and falls as rain again?How much sunlight does the rainforest receive each day? http://www.bbc.co.uk/learningzone/clips/rainforest-photosynthesis/3093.html What does rainforest take in? release out?Which 3 things do rainforests rely on?

• Biosphere= life support system. Why?

What’s in a rainforest?

• http://www.bbc.co.uk/learningzone/clips/rainforest-layering/3092.html

• Use the video clip to outline the structure of a typical rainforest- describe each layer

• Describe the distribution of tropical rainforests across the Earth

• Emergent - or forest giants, 50 metres or taller. These trees are usually supported by buttress roots.

• Canopy - This is a dense layer forming almost complete cover. Trees 20 - 30 metres tall include many hardwoods such as mahogany.

• Under Canopy - This dark and humid area contains saplings between the trunks of larger trees.

• Shrub Layer - This contains small trees and shrubs especially near rivers.

• Forest Floor - This is covered with ferns and a deep litter of fallen leaves

Contrasting uses of a rainforest.

• For each image create a spider diagram to illustrate the use of and effect on the rainforest.

Biomes – Goods and Services

• What do you think is the difference?

• Goods – products and items sourced from the biome for survival or commercial use.

• Services – measures the biome takes to serve the planet. e.g. regulating the composition of the atmosphere, maintaining the health of the soil.

List as many different goods and services you can think of.

• Goods • Services

What goods and services are provided by rainforests

• Sort the cards you have been given to determine the goods and services produced by our most productive land biome

They provide 80% of all western

foods- like pineapple, coffee

They are a source of Illegal drugs

like cocaine

Many indigenous people in

rainforests live the way they have lived for centuries they

can teach us a lot

They provide saleable

commodities like Rubber and

timber

Rainforests are places we can

visit on treks and holidays,

increasingly as eco-tourists

25% of all cancer fighting drugs

One rainforest drug, Rosie Periwinkle

improved childhood leukaemia sufferers

survival chance from 10 to 90%

Plants from rainforests are

used in the contraceptive pill

One rainforest drug is used to help diabetics

Small monkeys called marmosets from rainforests are used to test

drugs before human tests

Over 50% of the biological

diversity on Earth is found in

tropical rainforests

They provide homes for many

endangered animals species- such as Orang-Utans, Bonobos,

Poison Arrow frogs, etc

They are a unique biome

They regulate the hydrological cycle

They provide nutrients for soil to be productive

They store carbon, a

contributor to global warming

• http://www.at-bristol.org.uk/cz/rainforest/rainforest.htm

• Goes through main goods and services

• Includes people’s opinions of value of rainforest

Goods and services• Cocoa• Rubber• Bananas• Brazil Nuts• Pineapples• Sugar• Many medicines• Animals for drug tests

• Ecotourism• Endangered animals• Cosmetics• Colourings for lipstick• Timber• Plants• Tourism• Pets

Deforested-

Land for farming crops

Grazing cattle for beef production

Extracting underground minerals

How biosphere regulates carbonThe carbon cycle

http://www.youtube.com/watch?v=U3SZKJVKRxQ&feature=PlayList&p=C606EB957A1DDF22&playnext=1&playnext_from=PL&index=67 long video

http://www.youtube.com/watch?v=0Vwa6qtEih8&feature=PlayList&p=C606EB957A1DDF22&playnext=1&playnext_from=PL&index=49 short video

Estimated major stores of carbon on the Earth.

SinkAmount in Billions of

Metric Tons

Atmosphere578 (as of 1700) - 766

(as of 1999)

Soil Organic Matter 1500 to 1600

Ocean 38,000 to 40,000

Marine Sediments and Sedimentary Rocks

66,000,000 to 100,000,000

Terrestrial Plants 540 to 610

Fossil Fuel Deposits 4000

question answer

question

How is carbon taken in the environment   by photosynthesis  

how do organisms get carbon   by eating plants  

carbon is released back into the atmosphere by humans by  

breathing, or cellular respiration  

carbon is released back into the atmosphere through carbon dioxide when  

fossil fuels are burned  

volcanoes   release CO2  

show by photosynthesis  

how do organisms get carbon   show

carbon is released back into the atmosphere by humans by  

show

show fossil fuels are burned  

volcanoes   show

answer

• http://www.studystack.com/matching-1461 loads of games on the carbon cycle

• http://www.open2.net/historyandthearts/discover_science/launcher_elementonthemove.html element on move game- move round a carbon element

Which biomes hold most carbon?

• Rainforests

• Taiga

• Mangroves

• Coral reefs

• http://www.bbc.co.uk/learningzone/clips/rainforest-layering/3092.html

How the biosphere maintains soil health

NitrogenNitrogen is a central component of cell proteins and is used for seed production. It exists in

several chemical forms and various micro-organisms are involved in its transformations. Legumes and algae, are able to transform atmospheric nitrogen into a form available for plant use.

Nitrogen in dead organic materials is available to plants through mineralization. Nitrogen lost from the pasture system through the physical processes of leaching, runoff, and

erosion, and through residue burning. Nitrogen is needed for forage production and is lost easily, this nutrient is often the limiting

factor in crop production. Productive pasture management practices enhance the fixation and conservation of nitrogen while minimizing the potential for nitrogen losses.

Practices for effective nitrogen cycling in pastures include:

1) Maintaining stable or increasing percentages of legumes by not overgrazing pastures and minimizing nitrogen applications, especially in the spring.

2) Protecting microbial communities involved in organic matter mineralization by minimizing practices that promote soil compaction and soil disturbance such as grazing wet soils, tillage, and cultivation.

3) Incorporating manure and nitrogen fertilizers into the soil, and never applying these materials to saturated, snow-covered, or frozen soils.

• Avoiding pasture burning. If burning is required, it should be done very infrequently and then using a slow fire under controlled conditions.

• Applying fertilizers and manure according to a comprehensive nutrient management plan.

Nutrient Stores

Biomass Litter Soil

The total mass of living organisms,

mainly plant tissue

The amount of organic matter,

including humus and leaf litter, in the soil.

Soil.

Nutrient Stores

Biosphere and regulating the hydrological cycle

• Trees intercept precipitation• They then provide basis for evapotranspiration• They provide cover for soil to reduce soil erosion

and leaching of nutrients• The dead leaves create nitrogen stores-

imperative for the nutrient cycle we looked at earlier

• The removal of trees and any vegetation reduces interception and evapotranspiration, increasing surface runoff- interfering with the natural hydrological cycle

• So why after deforestation are these areas found to have some of the least fertile soils in the World?

• Imagine you are a farmer looking at the vegetation above. What would be your thoughts about how productive that land would be?

Goods and services provided by the BIOSPHERE

• What things do we get from rainforests?• What lies under deserts and tundra?• What do coral reefs provide us with?• What services do Savannas provide us with?

Task

Describe the goods and services that are produced by the rainforest ecosystem (4)

Explain why these goods and services are important to us (4)

Homework Task

• Produce a piece of work entitled either-• The rainforest is important to me because……• My rainforest connections….• I rely on the rainforest for…..• Your piece of work can be a written piece, a

poem, a collage, a story, a video, a storyboard• You must include details about-• The things you use that originate in a rainforest• Information about how the rainforest helps your

planet survive- the carbon, nutrient and hydrological cycles info)

Annotate the diagram giving examples of each link.

One has been done for you.

e.g Methane from cows

The nutrient cycle

• Study fig 5 Edexcel book.