Principles of Ecology

1. Principles of Ecology Unit 2Chapter 2

2. What is ecology? • Ecology: study of interactions that take place between organisms and their environment

3. Biosphere • the portion of the Earth that supports living things • Ex: ocean, forest, atmosphere.

4. Abiotic vs. Biotic factors • Abiotic = nonliving parts of the environment • Ex: light, air, temperature, soil • Biotic = living parts of the environment • Ex: bacteria, protist, fungus, plant, animal

5. Which is Biotic/Abiotic?

6. Levels of organization • In biology, we begin at the chemical level which make up cells… • Which make tissues… • Organs… • Systems… • And finally, the individual organism

7. Levels of organization from smallest to largest in an Ecosystem. • Organisms • Individual • Population • Community • Ecosystem • Biosphere

8. Levels of organization • In Ecology, we begin with the individual and move through the levels to the planet, Earth

9. Individual • made of cells, uses energy, reproduces, responds, grows, and develops

10. Population • group of organisms all of the same species, which interbreed and live in the same area at the same time

11. Community • interacting populations in a certain area at a certain time

12. Ecosystem • interacting communities and abiotic factors

13. Habitat vs. Niche • Habitat: place where organism lives • Niche: role or position a species has in its environment

14. End of What is Ecology Notes? • Now let’s do some practice!!!

15. Energy Flow Through an Ecosystem Notes Du (2)

16. Ecology and the flow of energy and matter • By the end of this portion of the notes you should be able to describe how matter and energy flow through trophic levels using various models, including food chains, food webs and ecological pyramids

17. How organisms obtain energy • Autotroph (producer): photosynthetic or chemosynthetic, makes own food • Heterotroph (consumer): “eat” other organisms, cannot make own food • Decomposer: breaks down dead or decaying organisms, recycles matter

18. Autotroph

19. The sugar produced by autotrophs (through photosynthesis) can then be used by heterotrophs for energy

20. Heterotrophs - scavengers • Scavengers: feed off of dead or decaying living things but do not recycle matter back into the ecosystem

21. Heterotrophs - herbivores • consume only vegetative matter • mostly primary consumers.

22. Heterotrophs - carnivores • obtain energy from eating other consumers • Secondary and tertiary consumers

23. Decomposers • Bacteria and fungi break down living matter and help release nutrients. • Decomposers are found at every level of the food chain. • They are nature’s recyclers. Typical examples: fungus and bacteria

24. Autotrophs Third-order heterotrophs Second-order heterotrophs First-order heterotrophs Decomposers

25. How Energy Flows • From producer (autotroph) to consumer (heterotroph) AUTOTROPH Water + CO2  Sugar + O2 HETEROTROPH Sugar + O2  water + CO2

26. Food chain • Series of steps in which organisms transferenergy by eating and being eaten • The arrows show the direction energy flows. • Trophic levels: feeding step berries → mice → black bear

27. Food web • shows interactions between organisms (all possible routes)

28. Energy pyramid Pyramid of Energy • Shows how much energy is available at each trophic (energy) level. • Only 10% of the available energy is transferred up to the next trophic level. The rest is released as heat Heat 0.1% Consumers Heat 1% Consumers 10% Consumers Heat Heat Parasites, scavengers, and decomposers feed at each level.

29. Pyramid of Numbers • Each level represents the number of organisms consumed by the level above it.

30. End of Lecture 2 Now lets practice!!

31. Ecology Notes 3 Cycles

32. Two cycles in nature • Carbon cycle • Nitrogen cycle

33. CO2 in Atmosphere • Carbon Cycle • driven by photosynthesis & respiration • recycles carbon, a primary component of all organic compounds CO2 in Ocean

35. Carbon cycle

36. Nitrogen Cycle • driven by decomposition of nitrifying bacteria and fungi • atmospheric nitrogen must be converted to a usable form(by plants) N2 in Atmosphere NO3– and NO2– NH3

38. Nitrogen cycle

39. Now let’s Practice Time to Draw some cycles.