1. Ecology
The world around us

2. Ecology
the study of the relationships among living things and their interaction with the environment

3. Ecosystem (Ecological System): An interacting system of living and non-living components.
A forest, a pond, a stream, a decaying log, an aquarium are all ecosystems. Sometimes called a habitat.

4. Biotic and Abiotic factors interact in complex ways in communities and ecosystems

5. Biotic factors
Living factors in an environment
Examples:

6. Abiotic factors
Nonliving factors in an environment
Examples:

7. Ecosystem Interactions
Habitat- the part of the environment in which an organism lives
Ex-
Niche- the role (job) an organism has

8. Levels of Organization

10. Population- individuals of a single species that share the same geographic location at the same time
Community- a group of interacting populations that occupy the same geographic area at the same time
Ecosystem- a community and all the abiotic factors (nonliving) that affect it
Biosphere- the part of Earth that supports life

11. I) Autotrophs: organisms that make their own food
Producers
photosynthetic organisms (green plants).
Examples:

12. II) Heterotrophs: organisms that consume other organisms

13. Primary Consumers “Herbivores”
Plant eating animals
Examples:

18. Secondary Consumers “Carnivores”
Meat eating animals,
may be primary, secondary tertiary or higher.
Examples:

23. Omnivores  
Animals that eat both plants and animals.
Examples:

27. Scavenger Animal that feeds on other animals that are already dead
Example: vulture

28. Decomposers:
Break down complex nutrients to return them to the environment for reuse.
Examples: bacteria, molds, tree bract, mushrooms, insect larva

31. Parasites:
organisms that take nutrients from, or use systems of, other living organisms.
Examples: tapeworm, some protozoans, leech, some fungus

32. Pathogens:
Disease causing microorganisms. Viruses, bacteria, some protists.
Examples: E. Coli, staph, strept, Flu virus, HIV virus

33. Community Interactions
Competition
Predation
Symbiotic relationships
Mutualism- organisms benefit from each other
Commensalism- one organism benefits and the other is neither helped nor harmed
Parasitism- one organism benefits while the other is harmed

34. The Canada Lynx and the Snowshoe Rabbit
Predator-Prey Relationships
- Predator hunts prey
The Canada Lynx and the Snowshoe Rabbit

38. Carrying Capacity: The number of organisms any habitat can support.
This is limited by the available energy, water, oxygen, and minerals, and by the ability of ecosystems to recycle the residue of dead organisms through the activities of bacteria and fungi.

39. Limiting Factors: a factor that controls a process, such as organism growth or species population, size, or distribution.
Examples: Food, water, shelter, disease, predators, etc.

41. Energy in an Ecosystem
Autotrophs capture energy,making it available for all members of a food web
Question: Where do they capture the energy from?

42. Energy Flow
Autotrophs (make their own food)  Heterotrophs (do not make their own food)
Decomposers- Recycle nutrients from any dead organism

43. Food Chain
Food chain- a series of organisms through which food energy is passed

44. Food web- many food chains connected

47. Biomagnification
Accumulation of substances in larger and larger quantities in bodies of organisms at each higher level of the food chain
Also known as bioaccumulation
How Biomagnification Works

50. Biomagnification occurs when contaminants that don’t easily degrade increase with each link of a food chain. In seawater, these persistent molecules stick to small particles and phytoplankton. Small fish eat the phytoplankton, but the contaminants can’t be broken down and are absorbed, intact, by the fish. When small fish are eaten by larger predators, the process repeats—again and again, up the food chain. Each subsequent predator receives a higher dose than the previous one. Animals at the top of the food chain, such as dolphins, receive the most concentrated dose of these contaminants with every meal.

51. Ecological Pyramids

52. The Energy Pyramid

53. Amount of energy available in an ecosystem
Greatest amount of energy = producers
Least amount of energy = highest level consumer
Pyramid of biomass- shows relative mass of organisms

54. Ecological Succession
The process by which an existing community is slowly replaced by another community

55. Ecological Succession
On Land
In water
Succession on a Glacial Moraine
Bog Succession

56. Pioneer Organisms Climax Community The first organisms to inhabit
an area
Examples: In Water: algae
On Land: lichen
Climax Community
Stable community that develops as a result of succession

57. Cycles of an Ecosystem
Essential nutrients are cycled through biogeochemical processes.
Water cycle
Carbon and Oxygen Cycles
Nitrogen Cycle
Phosphorous Cycle

63. The Oxygen/Carbon Cycle:

65. The Nitrogen Cycle
 Nitrogen is needed for the synthesis of proteins and nucleic acids. Plants can synthesize them from nitrates, animals must eat protein and nucleic acids.