Dynamic Planet- Sub unit 3

Battle for the Biosphere

3.1a What is the value of the biosphere?

To know what the biosphere isTo understand that the biosphere acts as a life support systemTo know and begin to appreciate the goods and services provided by various biomes

• 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 book

• Where 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= • the global sum of all ecosystems. It can also be

called the zone of life on Earth. The biosphere is the global ecological system integrating all living beings and their relationships, including their interaction with the elements of the lithosphere, hydrosphere and atmosphere.

Aspects of the planet to do with water

Aspects of the planet to do with the earth- rocks and soil, etc

Aspects of the planet to do with air around us- controlling climate

• 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

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

Carbon stored in the hydrosphere• Carbon dioxide enters the waters of the ocean by

simple diffusion. • Once dissolved in seawater, the carbon dioxide can

remain as is or can be converted into carbonate (CO3-2) or bicarbonate (HCO3-).

• Certain forms of sea life biologically fix bicarbonate with calcium (Ca+2) to produce calcium carbonate (CaCO3). This substance is used to produce shells and other body parts by organisms such as coral, clams, oysters and some algae.

• When these organisms die, their shells and body parts sink to the ocean floor where they accumulate as carbonate-rich deposits.

• After long periods of time, these deposits are physically and chemically altered into sedimentary rocks.

• Ocean deposits are by far the biggest sink of carbon on the planet

Carbon stored in the Lithosphere• Carbon is stored in the lithosphere in both inorganic and organic forms. • Inorganic deposits of carbon in the lithosphere include fossil fuels like

coal, oil, and natural gas, oil shale, and carbonate based sedimentary deposits like limestone.

• Organic forms of carbon in the lithosphere include litter, organic matter, and humic substances found in soils.

• Some carbon dioxide is released from the interior of the lithosphere by volcanoes. Carbon dioxide released by volcanoes enters the lower lithosphere when carbon-rich sediments and sedimentary rocks are subducted and partially melted beneath tectonic boundary zones.

• Since the Industrial Revolution, humans have greatly increased the quantity of carbon dioxide found in the Earth's atmosphere and oceans. Atmospheric levels have increased by over 30%, from about 275 parts per million (ppm) in the early 1700s to just over 365 PPM today. Scientists estimate that future atmospheric levels of carbon dioxide could reach an amount between 450 to 600 PPM by the year 2100.

• The major sources of this gas due to human activities include fossil fuel combustion and the modification of natural plant cover found in grassland, woodland, and forested ecosystems.

• Emissions from fossil fuel combustion account for about 65% of the additional carbon dioxide currently found in the Earth's atmosphere. The other 35% is derived from deforestation and the conversion of natural ecosystems into agricultural systems. Researchers have shown that natural ecosystems can store between 20 to 100 times more carbon dioxide than agricultural land-use types.

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

• 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?

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?

Tasks

• Answer questions from page of the handout sheet, in full sentences in your book

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)

Plenary

• Together we are going to create an improved version of figure 5 from chapter 3 of text book