1. The Biosphere

2. What is Ecology?
Scientific study of interactions among organisms and between organisms and their environment

3. Biosphere
Combined portions of the planet in which all of life exists, including land, water and air or atmosphere
Extends from 8 kilometers above Earth’s surface to 11 kilometers below the surface of the ocean

4. Interactions and Interdependence
Interactions within the biosphere produce a web of interdependence between organisms and the environment in which they live

5. Levels of Organization
Individual: interactions between an organism and its surroundings
cottontail rabbit
Population: groups of individuals that belong to the same species and live in the same area
group of cottontail rabbits

6. Levels of Organization
Communities: different populations that live together in a defined area
rabbits, coyotes, ravens, lizard
Ecosystem: collection of all the organisms that live in a particular place, together with their nonliving, or physical, environment
rabbits, coyotes, ravens, lizard, rocks, dirt, climate, water

7. Levels of Organization
Biome: group of ecosystems that have the same climate and dominant communities
desert, tundra, tropical rain forest
Biosphere: planet Earth

9. Ecological Methods Three approaches to ecological research:
Observing: Use of 5 senses to ask ecological questions
Experimenting: Used to test hypotheses
artificial environment in a lab
within natural ecosystems

10. Ecological Methods
Modeling: Used to gain insight into complex phenomena such as the effects of global warming
may include mathematical formulas based on data collected through observation and experimentation
predictions tested by further observations and experiments

11. Biotic and Abiotic Factors

12. Biotic Factors ‘Bio’- Means ‘life’
Definition - organisms that make up the living portion of an ecosystem
Also considered the ORGANIC component of the ecosystem
Ex. Trees, shrubs, insects, animals, algae, fungi, etc

13. Abiotic Factors ‘Abio’ – Means ‘not life’
Definition – the nonliving features of an environment
Considered the INORGANIC component of the ecosystem
Ex. Air, temperature, moisture, light, rocks, and soil

14. Energy Flow
Energy flows from the sun or inorganic compounds to producers.
Consumers eat producers to get energy.
The primary source of energy on Earth is the sun!!

15. Every Organism Has a Home Address

16. Habitat Definition – physical location in which an organism lives
In other words the home address of a species
Ex. Fern habitat – moist, shady forest floor.

17. Habitat Many animals can share a habitat
A single tree maybe the habitat for several species of birds, squirrels, etc.
However, each species uses the habitat in a different way.
They all find their niche
Coral reef biodiversity.

18. Niche
Definition – the way a species uses the resources of its habitat and what it does in the community
Includes: food, living space, methods of obtaining food, etc.
NO TWO SPECIES CAN OCCUPY THE SAME NICHE

19. Producers Autotrophs – “self feed”
Use sunlight to create carbohydrates via photosynthesis
Ex – Plants, algae and some bacteria
Some bacteria create organic compounds from inorganic chemicals – Chemosynthesis
Live in remote places.

20. Producers

21. Consumers Heterotroph – “Different food” Must eat to obtain energy.
Ex – animals, fungi, some protists

22. Types of Heterotrophs Herbivore – eats plants Carnivore – eats animals
Omnivore – eats plants and animals
Detritivore – eats detritus (plant and animal remains)
Ex- snails, crabs, earthworms
Decomposer – breaks down organic matter
Ex – bacteria and fungi

23. Carnivore
Decomposers
Omnivore
Detritivore

24. Feeding Relationships
Energy flows through an ecosystem in one direction,
from the sun or inorganic compounds  autotrophs (producers)  various heterotrophs (consumers).

25. Food Chain
A series of steps in which organisms transfer energy by eating and being eaten.
i.e. Wheat  mouse  snake  hawk

26. Food Chain Example

27. Food Web
Network of complex interactions formed by the feeding relationship among the various organisms in an ecosystem.

29. Trophic Levels Each step in a food chain or food web
1st level = producers
2nd, 3rd, or higher levels = consumers
Usually no more than 5 levels because 90% of energy is lost at each level.
Only 10% of the energy is transferred to the next trophic level

30. Ecological Pyramid
A diagram that shows the relative amounts of energy or matter contained within each trophic level in a food chain or food web.
Energy, biomass, and population numbers can all be represented by a pyramid.

31. Ecological Pyramid

32. Cycles of Matter Recycling in the Biosphere
Matter is recycled within and between ecosystems.
Matter moves through an ecosystem in biogeochemical cycles.

33. Water Cycle

34. Water Cycle Main steps of water cycle Evaporation Condensation
Precipitation
Transpiration

35. Carbon Cycle

36. Carbon Cycle Release Carbon into Atmosphere
Plant and animal respiration
Burning fossil fuels
Pull Carbon from Atmosphere
Photosynthesis (plants)
Ocean uptake

37. Nitrogen Cycle
N2 in Atmosphere
NH3
NO3-
and NO2-

38. Nitrogen Cycle 78% of Earth’s atmosphere is Nitrogen gas = N2
Nitrogen containing products:
Ammonia (NH3)
Nitrate ions (NO3-)
Nitrite ions (NO2-)
Nitrogen is needed for protein and nucleic acid synthesis

39. Nitrogen Cycle
Converting nitrogen gas into ammonia is called nitrogen fixation.
Only certain types of bacteria can do this.
Plants use the converted products (NH3, NO3- ,& NO2-) to make plant proteins.
Some bacteria convert solid nitrates into nitrogen gas (denitrification).

40. Phosphorus Cycle

41. Phosphorus Cycle
Phosphorus is important for the formation of DNA and RNA molecules.
Phosphorus is not very common and does not enter the atmosphere, instead it is found mostly on land in rock and soil.

42. Primary Productivity
The rate at which producers create organic matter.
Determines the size of the community.
Limited by availability of nutrients.
Land – phosphorus (P), nitrogen (N), potassium (K)
Marine – nitrogen
Fresh water - phosphorus

43. Algal Bloom

44. Red Tide
domoic acid, a chemical responsible for amnesic shellfish poisoning in humans Read more: Red Tide - Marine toxins and their effects