ECOLOGY AND ECOSYSTEMS (BASIC CONCEPTS – SOME REVIEW)

1. ECOLOGY AND ECOSYSTEMS (BASIC CONCEPTS – SOME REVIEW)

2. Ecology • Ecology is the study of the relationships between living organisms and their physical environment • How do the connections work between plants and animals and the world around them • Ecologists are scientists who study these relationships

4. Lithosphere- earth’s outer crust Hydrosphere- water bodies Atmosphere- air (N2, O2, CO2, H2O) Biosphere- all the living parts of the Earth The 4 spheres of earth

5. All spheres are connected to each other and ALL of them are powered by the sun’s energy.

6. Individual: a single organism Species: organisms which can mate and produce fertile offspring Population: all the individuals of the same species living in one area Community: all the living organisms in one area Ecosystem: all biotic and abiotic components in a specific physical area (and the relationships between) Biome: a collection of similar ecosystems Biosphere: the living parts of the Earth Levels of organization of life

8. Ligers, zonkeys and mules (oh my) A side-note; what is a species?

9. biomes

10. 1. TUNDRA- permafrost, low vegetation (no trees), short growing season, low biodiversity Canadian biomes

11. 2. Boreal Forest (also called the Taiga)- coniferous forest (evergreens), ponds, lakes, bogs, heavy snows, found in every province

12. 3. TEMPERATE DECIDUOUS FOREST- highest biodiversity, rich soil, most rainfall, deciduous trees (lose leaves in the fall)

13. 4. GRASSLAND (prairies)- lower rainfall cannot support trees, rich/deep soil, converted to fertile farmland

14. 5. TEMPERATE RAINFOREST- deciduous trees, mild temperature, most rainfall in Canada, tallest trees in Canada

15. 6. DESERT (yes we have some small deserts!)- all in British Columbia / Yukon, sand or sandy soil, low rainfall, many days of sunshine

17. ABIOTIC – non-living factors in an ecosystem Examples: temperature, wind, water, rocks and minerals, sunlight … BIOTIC – living factors in an ecosystemExamples: animals, plants, bacteria, rotting logs, decaying organisms…..) Ecological terms - review

18. PREDATOR– an animal that hunts and kills another animal for food SCAVENGER– an animal that searches for carrion (dead animals) to eat – e.g. vulture, raven, hyena

19. DETRITIVORE– an organism that consumes dead matter and animal wastes (E.g. earthworms, snails, fly larvae, dung beetles)

20. DECOMPOSER– an organism that breaks down dead organisms and returns nutrients to the soil (E.g. Bacteria, Fungi)

21. HABITAT – the area where an organism lives (or spends most of its time) SYMBIOSIS – organisms that live in very close contact with each other (usually inside or on or around most of the time)

22. mutualism - both organisms benefit from the relationship

23. parasitism - One organism benefits, the other is harmed

24. commensalism - One organism benefits, the other is neither benefited or harmed

25. Organisms compete for some resource (food, water, habitat …..) A) INTERSPECIFC COMPETITION- competition between different species (e.g. elephants, zebras, giraffes at one watering hole) competition

26. B) INTRASPECIFIC COMPETITION -competition between organisms of the same species(e.g. male birds or frogs vocalize in spring to compete against each other for mates) competition

27. Also called “species richness” – the number of different species living in an ecosystem Which biome has the highest biodiversity in Canada? The lowest? Highest: Deciduous Forest Lowes: Tundra biodiversity

28. Ecology review - continued

29. Show feeding relationships and trophic levels. Food chains and food webs trophe (Greek) means food. 1st 2nd 3rd 4th The arrow points in the direction of energy flow.

33. Simplified!!!

35. Normally humans are at the top of the food chain, however…….

36. Producers (plants - make their own food) Consumers (must eat other organisms) Herbivores (Primary Consumers) only eat plants Carnivores (Secondary / Tertiary Consumers): only eat other animals Ominivores: eat both plants and animals Food chain terms

38. All energy in any ecosystem begins with the sun As animals live and feed, the energy decreases at each trophic level Why? Energy is lost through heat, movement, internal life processes within the organism Approximately 90% is lost at each trophic level. This is why maximum food chain length is only about 5 or 6 levels (and why there are more mice in the forest than bears!) Energy pyramids

39. 90% energy loss each level

41. 4 variables determine the positive or negative growth (decrease) Births (+) Immigration (+) Deaths (-), Emmigration (-) %Growth = (B + I) – (D + E) x 100 Initial Population Example…. Population levels are always changing

42. 1n 2009 there were 75 whitetail deer living in Rondeau Provincial Park. Over the course of one year, 26 are born, 19 die, 4 move into the park and 22 leave the park. What is the percent population growth? Initial Population = 75 B = 26 D = 19 I = 4 E = 22 %Growth = (B + I) – (D + E) x 100 (Init. Pop) % Growth = (26 + 4) – (19 + 22) x 100 = - 11 x 100 = - 14.7 % 75 75 Negative means the population decreased

43. Factors which limit population size Density-Dependent factors affect populations because of the density of the population (food, water, disease, habitat…..) Limiting factors

45. Density-Independentfactors affect population growth regardless of its size (natural disasters, use of pesticides, global warming …..) Limiting factors

46. Carrying capacity is the maximum population of a species that can be indefinitely supported by an ecosystem (usually fluctuates around an average) Carrying capacity