Earth from geological viewpoint

Earth from meteorological viewpoint

Earth from ecological viewpoint

Earth as huge system of interdependent, interacting, parts

The 4 components of Earth

1. Lithosphere: the solid Earth; land, soil

The 4 components of Earth2. Hydrosphere: the liquid Earth;

water

The 4components of Earth3. Atmosphere: the gaseous Earth; air

The 4 components of Earth

4. Organisms: living things

BiosphereIncludes parts of all 4 components of Earth

in which living things occur.

Levels of organization in the living world

Levels of organization in the living world

• Organisms: individual living things

Levels of organization in the living world

• Population: group of individuals of same species occupying a given area at the same time.

Levels of organization in the living world

• Community: populations of all species occupying a particular place

Levels of organization in the living world

• Ecosystem: community(ies) interacting with one another and with the physical environment in a particular place

Levels of organization in the living world

• Biome: a major category of ecosystem (e.g., desert, grassland, tropical rainforest, etc.)

ECOLOGY• Ecology: the scientific study of

ecosystem structure and function• Ecologists vs. Environmentalists

Structure of ecosystems1. Energy source

– Usually sunlight

Deep sea vent

Structure of ecosystems2. Physical environment: non-living

materials like air, water, minerals, etc.

Structure of ecosystems3. Producers

– Make their own food

Structure of ecosystems4. Consumers

– Eat other living things– Primary– Secondary

Structure of ecosystems5. Decomposers

– Eat waste matter and dead living things

Function of ecosystems• All ecosystem interactions depend

on–1. One-way flow of energy–2. Matter cycling

Energy Flow• Energy: the ability to do work• Energy quality: measure of ability

to do work

Energy Flow• Energy: the ability to do work• Energy quality: measure of ability

to do work– High: organized, concentrated; great

ability to do work. Ex. electricity

Energy Flow• Energy: the ability to do work• Energy quality: measure of ability

to do work– High: organized, concentrated; great

ability to do work. Ex. electricity– Low: disorganized or dilute; low

ability to do useful work. Ex. heat less than 100°C

Laws of thermodynamics• 1. Matter and energy can’t be created

or destroyed, only transformed – You can’t get something for nothing– There’s no such thing as a free lunch– E = mc2

• 2. Energy degrades to a less usable, lower quality form (low heat is lowest)– Energy quality “tax” – You can’t win– You can’t get out of the game, either

One-way flow of energy– Food chain: a series of organisms,

each eating or decomposing the preceding one. A channel for one-way flow of energy (and the recycling of materials).• Individual organisms

One-way flow of energy• Food Web: a tracing of movement

of all energy (and matter) passing through an ecosystem.

• Including all interconnected food chains

One-way flow of energy• Some concepts

– Pyramid of energy: due to the “energy quality tax” of the second law of thermodynamics, only 2-30% of the energy a one trophic level is transferred to the next trophic level• Depends on species and ecosystems

involved• The “average” number is 10%

One-way flow of energy– Pyramid of numbers and biomass:

related to the pyramid of energy. • More people can be supported by plants

than by animal meat

One-way flow of energy• Pyramid of numbers and biomass:

1300

90,00027,000,0001000 tons

HumanTroutFrogs

GrasshoppersGrass

One-way flow of energy– Pyramid of numbers and biomass:

1300

90,00027,000,0001000 tons Grass

HumanTroutFrogsGrasshoppers

3090,000

27,000,0001000 tons Grass

HumansFrogs

Grasshoppers

One-way flow of energy– Pyramid of numbers and biomass:

1300

90,00027,000,0001000 tons Grass

HumanTroutFrogsGrasshoppers 900

27,000,0001000 tons Grass

HumansGrasshoppers

One-way flow of energy– Pyramid of numbers and biomass:

1300

90,00027,000,0001000 tons Grass

HumanTroutFrogsGrasshoppers

2,0001000 tons Grass

Humans

One-way flow of energy– Net Primary Productivity: rate at

which plants produce chemical energy (PSS) MINUSthe rate at which plants use chemical energy (respiration)• The “income” of animals

So, which biomes on Earth are the most productive?

Open ocean Tropical rain forest Temperate forest Savanna Northern coniferous forest Continental shelf Agricultural land Temperature grassland Woodland and shrubland Estuaries Swamps and marshes Desert scrub Lakes and streams Tundra Extreme desert

0 50 100 150 200

Average World Net Primary Productivity (billion Kcal/yr)

Estuaries Swamps and marshes Tropical rain forest Temperate forest Northern coniferous forest Savanna Agricultural land Woodland and shrubland Temperature grassland Lakes and streams Continental shelf Tundra Open ocean Desert scrub Extreme desert

0 2,500 5,000 7,500 10,000

?

Average World Net Primary Productivity (billion Kcal/m2/yr)Kcal/m2/yr

Estuaries Swamps and marshes Tropical rain forest Temperate forest Northern coniferous forest Savanna Agricultural land Woodland and shrubland Temperature grassland Lakes and streams Continental shelf Tundra Open ocean Desert scrub Extreme desert

0 2,500 5,000 7,500 10,000

?

Average World Net Primary Productivity (billion Kcal/m2/yr)Kcal/m2/yr