1. Major Ecosystems of the World
Chapter 6
Major Ecosystems of the World

2. Earth’s Major Biomes

3. Earth’s Major Biomes
Type of biome controlled by temperature and precipitation

4. Earth’s Major Biomes Tundra Characterized by:
Very short growing season
Little precipitation (10-25 cm / yr)
Permafrost
Low species diversity

5. Earth’s Major Biomes
Tundra

7. Earth’s Major Biomes Boreal Forest (Tiaga) Characterized by:
Short growing season
Low precipitation (~50 cm / yr)
Dominated by conifers (spruce, fir), but also has aspen, birch

8. Earth’s Major Biomes
Boreal Forest (Tiaga)

10. Earth’s Major Biomes Temperate Rain Forest Characterized by:
Cool; high precipitation (~127 cm / yr)
Dominated by evergreens (hemlock, spruce, cedar)
Heavily logged

11. Earth’s Major Biomes
Temperate Rain Forest

13. Earth’s Major Biomes Temperate Deciduous Forest Characterized by:
Hot summers, cold winters
Moderate precipitation ( cm / yr)
Dominated by oaks, hickory, maple
Commonly converted to agriculture

14. Earth’s Major Biomes
Temperate Deciduous Forest

16. Earth’s Major Biomes Grasslands Characterized by:
Hot summers, cold winters
Low to moderate precipitation (25-75 cm / yr)
Dominated tallgrass or shortgrass prairies
Heavily converted to agriculture

17. Earth’s Major Biomes
Grasslands

19. Earth’s Major Biomes Chaparral Characterized by:
Dry summers, mild winters
Frequent fires
Dominated by short pines, evergreen shrubs, scrub oak (but varies worldwide)

20. Earth’s Major Biomes
Chaparral

22. Earth’s Major Biomes Deserts Characterized by:
Wide daily variations in temperature
Very dry (<25 cm precipitation / yr)
Sparse plant coverage

23. Earth’s Major Biomes
Deserts

25. Earth’s Major Biomes Savanna Characterized by:
Precipitation cm / yr, but very seasonal with extended dry periods
Dominated by grasses, with occasional trees
African most famous for herds of wildebeest, antelope, zebra

26. Earth’s Major Biomes
Savanna

28. Earth’s Major Biomes Tropical Rain Forests Characterized by:
Very high precipitation cm / yr
Very nutrient-poor soil
Extremely high primary productivity
Extremely high species richness

29. Earth’s Major Biomes
Tropical Rain Forests

31. Earth’s Major Biomes
Vertical Zonation: The Distribution of Vegetation on Mountains

32. Earth’s Major Biomes

33. Aquatic Ecosystems Fundamental division: Freshwater vs. Saltwater
But, both contain 3 ecological category of organisms:
Free floating plankton (Phyto- & Zoo- )
Strongly swimming nekton
Bottom-dwelling benthos

34. Aquatic Ecosystems Freshwater Ecosystems Rivers and Streams
Tend to be narrow, swift, clear, cold, nutrient poor, and highly oxygenated
Tend to be wide, slow, cloudy, warm, nutrient rich, and less oxygenated

35. Aquatic Ecosystems Freshwater Ecosystems Lakes and Ponds
Photosynthetically productive; large fish
Highly productive, high species richness

36. Aquatic Ecosystems Freshwater Ecosystems Lakes and Ponds
Not always present; anaerobic, dominated by decomposers

37. Aquatic Ecosystems Freshwater Ecosystems
Thermal stratification in temperate lakes

38. Aquatic Ecosystems
Freshwater Ecosystems
Turnover in temperate lakes

39. Aquatic Ecosystems Freshwater Ecosystems Marshes and Swamps
Highly productive
Nutrient rich due to slow decomposition
Remove many pollutants
Provides flood control
Habitat & Food
Nesting sites
Groundwater Recharge

40. Aquatic Ecosystems Estuaries: Where freshwater and saltwater meet.
Highly variable environment
(salinity, temperature, light penetration rapidly changes).
Many fishes and shellfish spend larval stages here.

41. Aquatic Ecosystems Estuaries Two general types: 1) Salt marshes
2) Mangrove forests

42. Aquatic Ecosystems
Case-in-Point: The Chesapeake Bay

43. Aquatic Ecosystems
Marine
Ecosystems

44. Marine Ecosystems
Intertidal Zone
Aquatic Ecosystems

45. Aquatic Ecosystems Marine Ecosystems Benthic Environment
Photic benthic environments include:
1) Sea grasses

46. Aquatic Ecosystems Marine Ecosystems Benthic Environment
Photic benthic environments include:
1) Sea grasses
2) Kelp forests

47. Aquatic Ecosystems Marine Ecosystems Benthic Environment
Photic benthic environments include:
1) Sea grasses
2) Kelp forests
3) Coral reefs

48. Aquatic Ecosystems
Types of Coral Reefs
(a) Fringing reef

49. Aquatic Ecosystems
Types of Coral Reefs
(b) Atoll

50. Aquatic Ecosystems
Types of Coral Reefs
(c) Barrier reef

51. Aquatic Ecosystems Human Impacts on Coral Reefs
Sedimentation / siltation
Pollution
Overfishing
Direct disturbance (anchor dragging, divers damaging / collecting specimens)

52. Aquatic Ecosystems Marine Ecosystems The Neritic Province
Dominated by floating and swimming organisms.
Such as many large fishes, sea jellies, various plankton.

53. Aquatic Ecosystems Marine Ecosystems The Oceanic Province
Largest area of ocean
Least explored area

54. Aquatic Ecosystems
Human Impacts on the Ocean

55. Aquatic Ecosystems
Human Impacts on the Ocean

56. Interaction of Life Zones
Case-in-Point: The Everglades