• Ecosystems and stability

• Interrelationships among organisms, incl. symbiosis

• Competition and niches

• Illustrating energy flow – the SUN!

• Trophic levels and detritivores

• Population and density

• Density-independent vs. density-dependent factors

• Abiotic vs. biotic factors

• Primary and secondary succession

• Pioneer species and climax communities

• Geochemical cycles

1. T/F: Matter can be created and destroyed.

2. What are 2 ways that carbon is cycled in the environment?

3. What are 2 ways that nitrogen is cycled in the environment?

4. What are 2 ways that water is cycled in the environment?

1. T/F: Matter can be created and destroyed.

2. What role does bacteria play in the Nitrogen Cycle?

3. How do living organisms recycle carbon?

Agenda

Notes; Retake Reminder

Project; Study Guide

Date: _____________

• Biosphere: portion of Earth inhabited by life

–Interconnected with the atmosphere, the hydrosphere, and the geosphere

–All of these systems have to interact in order for an ecosystem to maintain itself

• The atmosphere is the result of life processes from the past and present – Photosynthetic organisms produce enough O2 to live off

of, for other organisms to live off of, AND to balance with the CO2 in the environment

– Oxygen from photosynthesis also makes up the ozone layer and prevents the sun’s UV rays from reaching Earth’s surface

– Normal cycling of O2 and CO2 in living organisms helps maintain a balance of these gases

– Nitrogen is maintained via the nitrogen cycle – Water is maintained through the water

cycle • Water evaporates, forms clouds, and rains back down to

the Earth’s surface – the air is thus cleaned after rain or snow fall.

• Greenhouse effect: normal warming effect when gases trap heat in the atmosphere – Greenhouse gases: CO2, O2, methane, water

vapor • They help trap heat energy and maintain

temperatures • Do not allow heat to pass very

well – Earth’s released heat stays trapped under the atmosphere

• CO2 cycles based on how many plants use it for photosynthesis AND how much the oceans absorb

Amount of

CO2 in the

atmosphere

Greenhouse

effect

Average Global

Temperature

Plant

cover on

Earth

Rate of

photosynthesis

Amount of

CO2

absorbed

by plants

Amount of

CO2 in the

atmosphere

higher increases increases increases increases increases decreases

lower decreases decreases decreases decreases decreases increases

• Part of the geosphere

• Soils on Earth are constantly generated and eroded

• Soil is composed of inorganic minerals, organic matter, water, and air

• Soil generation is based on weathering of inorganic materials and decaying organic matter

• Soil erosion and deposition are natural processes that move soil from one location to another (wind and water) – Usually plants ensure soil production at least equals

erosion, so the amount of soil remains constant

• Presence of soil allows for succession to occur

• Maintained by the energy of the Sun and the effect of weather

• Purifies water in several ways: –Evaporation creates pure water

–Water seeps through soil and rock and is filtered

–Slow water flow causes heavier particles to settle and the water is purified

• Waste from organisms are decomposed by bacteria or other organisms in the soil or aquatic ecosystem

• Nutrients are cycled from organisms to the environment back through geochemical cycles

• Project

• Study Guide

Amount of

CO2 in the

atmosphere

Greenhouse

effect

Average Global

Temperature

Plant

cover on

Earth

Rate of

photosynthesis

Amount of

CO2

absorbed

by plants

Amount of

CO2 in the

atmosphere

higher increases increases increases increases increases decreases

lower decreases decreases decreases decreases decreases increases

1. What is the biosphere?

2. The biosphere is made up of what other three "-spheres"?

3. How is the atmosphere maintained?

4. What is the greenhouse effects?

5. Name the 4 greenhouse gases.

6. What is soil composed of?

7. What types of organisms dispose of waste and recycle nutrients?