ECOSYSTEMS

1. ECOSYSTEMS SC Standard B-6: Students will demonstrate an understanding of the interrelationships among organisms & the biotic & abiotic components of their environment

2. What is Ecology? • is the scientific study of interactions among organisms and between organisms & their environment • Levels of Organization • Individual organism • Population • Community • Ecosystem • Biome • Biosphere

3. Ecological Methods • Observing • used to do basic counts or as 1st step of experiments • Experimenting • conducted in laboratory or in natural world • Modeling • use models to gain insight into large-scale or complex phenomena • insights gained from studying models often followed up with further observations & experiments in real world

4. What is an Ecosystem? • Community: a group of various species that live in the same habitat & interact with each other • Ecosystem: a community of organisms & their abiotic environment

5. What is an Ecosystem? • Biotic factors: describes living factors in an ecosystem • Includes dead organisms & the waste of organisms • Abiotic factors: includes the physical or nonliving factors of an environment • Examples: rock, air, water, sunlight, climate

6. Biosphere Biome Group of ecosystems with same climate,& similar dominant communities • Part of Earth in which life exists, including: land, water, air (atmosphere)

7. Biomes of the World

8. HABITAT • place where an organism usually lives

9. BIODIVERSITY • Includes: • the variety of organisms in a given area • the genetic variation within a population • the variety of species in a community • the variety of communities in an ecosystem

10. Biodiversity is low in habitats with extreme abiotic factors: Artic Circle, Antarctica • also, the open ocean has low biodiversity • Areas with low biodiversity can be easily damaged.

11. Areas with high biodiversity are more likely to resist damage

12. What is an Ecosystem? • What are the two ecosystems with the greatest biodiversity?

13. What is an Ecosystem? • Tropical Rainforest • Coral Reef

14. SUCCESSION • the replacement of one type of community by another at a single location over a period of time

15. Primary: Starts with bedrock Volcanic island or receding glacier Starts with lichen, mosses (pioneer species) Secondary: Starts with soil Example: huge forest fire leaves only soil behind In the soil are organisms, seeds Recovery much shorter Starts with grasses, weeds, shrubs Jack pine requires high temperature for seed to be released Succession

16. Pioneer species: the 1st organisms to appear in a newly made habitat example: new volcanic island receding glacier Lichens, Mosses What is an Ecosystem?

17. What is Lichen? • It is a mass of fungal & algal cells that grow together in a symbiotic relationship & that are usually found on rocks or trees • Symbiosis: a relationship in which 2 different organisms live in a close association with each other

20. Lichens • Some colonies estimated to be > 9,000 years old • Uses: • Antimicrobials • Dyes • Repel herbivores • Discourage competition from other plants • Eaten by reindeer & caribou

21. Primary Succession • After the lichens & mosses have formed soil: grasses & weeds start to grow  shrubs  pine trees  hard wood trees

22. Ecosystems respond to change so that it will be restored to equilibrium

23. Equilibrium • Sometimes, the ecosystem will find an equilibrium in which different species dominate after a change. • Example: if rainfall higher than normal one species of grass dominates the savanna but when there is a drought, a drought-resistant grass dominates

24. CLIMATE • the average weather conditions in an area over a long period of time

25. BIOME • a large region characterized by a specific type of climate & certain types of plant & animal communities

26. 2 key factors of climate that determines biomes are: • Temperature • Precipitation

27. Most organisms are adapted to live in a certain range of temperatures and water availability

28. Terrestrial Biomes • Grouped by latitude into: • Tropical • Near equator • Temperate • 30º – 60º • High-latitude • > 60º

29. Tropical Biomes • All warm but have differing amounts of rainfall • Tropical Rainforests

30. Layers: Emergents 100 – 120 ft tall Canopy Light available at top Little air movement, hi humidity Understory Layer little light (<3%) Trees have arrested growth until more light becomes available Forest floor Little growth: light 1%, water scarce The most complex in terms of structure & biodiversity Tropical Rainforest

31. Less rain than rainforest Have long dry seasons followed by short wet season 2. Savanna: Tropical Grasslands

32. Have very little annual rainfall Low biodiversity 3. Tropical Deserts

33. Have wide range of temperatures 4 temperate biomes Grasslands Forests Deserts Rainforest Temperate Biomes

34. moderate precipitation Rain & Snow cooler temperatures than Savanna 1. Temperate Grasslands

35. Deciduous Forests Shed leaves in fall Evergreens Animals: Deer Squirrel Beaver Raccoons 2. Temperate Forests

36. cooler than tropical deserts and have wider range of temperatures 3. Temperate Deserts

37. Temperate Rainforest • found in Washington State

38. Aquatic Biomes: Freshwater Includes: ponds lakes streams rivers

39. Freshwater Biomes

40. Include swamps, bayou Have high biodiversity with many plants, insects, crustaceans, reptiles, amphibians, birds, fish, and mammals Aquatic Biomes: Wetlands

41. Marine Ecosystems include kelp forests, coral reefs, and the open ocean A Kelp Forest: Aquatic Biomes: Marine Ecosystems

42. Estuary Area where fresh water from rivers & streams mixes with salt water in seas Organisms adapted to varying concentrations of salt High biodiversity : many fish lay their eggs here, crustaceans, bivalves Mangroves: Aquatic Biomes: Estuaries