1. Chapter 3: The Biosphere

2. Chapter 3 Outline
3-1: What is Ecology? 3-2: Energy Flow 3-3: Cycles of Matter

3. 3-1: What is Ecology? Interactions and Interdependence
Levels of Organization
Ecological Methods

4. Interactions and Interdependence
Ecology – the scientific study of interactions among organisms and between organisms and their environment
Biosphere – The combined portions of the planet in which all life exists.

5. Levels of Organization in Biology

6. Levels of Organization
Species – groups of organisms that can breed and produce fertile offspring.
Population – group of organisms of the same species that live in the same area
Community – all the living organisms found in an area.
Ecosystem – all the organisms that live in a place, along with their environment.
Biome – group of ecosystems that have the same climate and similar dominant communities.
Biosphere – the combined portions on Earth where living things are found.
More Inclusive

7. Ecologists study the environment in 3 ways:
Observing
Experimenting
Modeling

8. 3-2: Energy Flow Producers Consumers Feeding Relationships
Energy From the Sun
Energy Without Light
Consumers
Feeding Relationships
Food Chains
Food Webs
Trophic Levels
Ecological Pyramids

9. Producers Ecosystems need a source of energy to survive.
For most ecosystems, the main source of energy is the Sun.
Energy!

10. Like at this deep sea vent!
For a few ecosystems, it comes from chemical energy from the earth.
Chemosynthesis:
Carbon dioxide + hydrogen sulfide carbohydrates + sulfur
Energy!
Like at this deep sea vent!

11. Producers
A producer is an organism (like plants, algae or bacteria) that produces its own food
Chemosynthesis – energy from inorganic chemical compounds is used to make food (some bacteria)
Photosynthesis – energy from the Sun is used to make food (plants, algae, some bacteria)
Producers are autotrophs because they make their own food.

12. Consumer A consumer is an organism that eats another organism
Another word for consumer: heterotroph

13. Types of consumers(heterotrophs):
Herbivores obtain energy from eating producers (autotrophs)
Carnivores eat herbivores or other heterotrophs.
Omnivores obtain energy from eating both autotrophs and heterotrophs.
Detritovores obtain energy from eating plant and animal remains (detritus)
Decomposers obtain energy from organic matter (things that were once alive).

14. Energy can be tracked throughout the ecosystem through feeding relationships

15. Food Chain
A food chain is a series of steps in which organisms transfer energy by eating and being eaten.

16. Food Web
A food web is the network of complex interactions formed by the feeding relationships among the various organisms in an environment.

17. Food Web
Each step in a food chain or a food web is called a trophic level.

18. Food Web
A food web shows all the possible feeding relationships in an ecosystem.
How are food chains and food webs the same?
How are they different?

19. Only 10% of the energy is transferred to each trophic level.

20. Energy loss can be measured in biomass of organisms.

21. Energy loss and biomass comparison
Energy flows one way in an ecosystem:
Producers  1st Level Consumers  2nd Level Consumers  3rd Level Consumers

22. 3-3: Cycles of Matter Recycling in the Biosphere The Water Cycle
Nutrient Cycles
The Carbon Cycle
The Nitrogen Cycle
The Phosphorus Cycle
Nutrient Limitation

23. Recycling in the Biosphere
Unlike energy, matter is recycled within and between ecosystems.
Matter is passed from one organism to another and from one part of the biosphere to another through biogeochemical cycles.

24. The Water Cycle Section 3-3 Condensation Precipitation Evaporation
Transpiration
Evaporation
Runoff
Seepage
Root
Uptake

25. The Water Cycle
Water can enter the atmosphere by evaporation and transpiration
Evaporation – water changing from a liquid to a gas.
Transpiration – water evaporating through tree leaves.
Water cools in the air and condenses into clouds.
Water falls to the ground as precipitation.
Water makes its way to the ocean by runoff.

26. Nutrient Cycles
A nutrient is a substance an organism needs to sustain life.
Some common nutrients are:
Carbon (C)
Nitrogen (N)
Phosphorous (P)

27. Carbon Important for: Co2 Released into the atmosphere by:
Living tissue
Animal skeletons
Photosynthesis
Cellular respiration
Co2
Released into the atmosphere by:
Breathing, volcanoes, burning trees & fossil fuels
Absorbed by:
Oceans, Plants (esp. trees, algae),

28. The Carbon Cycle
Section 3-3
CO2 in
Atmosphere
CO2 in Ocean

29. Nitrogen Found in the air, and in dead things and poop: Important for:
N2 = nitrogen gas – 78% of the atmosphere – unable to be used by producers
NH3 = ammonia
NO3- = nitrate found in dead things, able to be used by living things
NO2- = nitrite
Important for:
Making proteins
Some bacteria convert nitrogen gas into ammonia using nitrogen fixation, so producers can use them.
N2  NH3
Some bacteria convert nitrates back into nitrogen gas using denitrification.
NO3-  N2

30. The Nitrogen Cycle
Section 3-3
N2 in Atmosphere
NO3-
and NO2-
NH3

31. Phosphorous Important for: NOT found in the atmosphere
Making nucleic acids (DNA, RNA)
NOT found in the atmosphere
Mostly found in rocks and soil minerals, and in ocean sediments.

32. Nutrient Limitation
primary productivity – the rate at which organic matter is created by producers
When an ecosystem has low primary productivity because it doesn’t have enough of a single nutrient, we call that a limiting nutrient.
A common limiting nutrient is phosphorous (P).

33. Limiting Nutrient