1. Communities, Biomes, and Ecosystems
Chapter 3
Communities, Biomes, and Ecosystems

2. Community
A group of interacting populations that occupy the same area at the same time.
Plants, animals, bacteria, etc.

4. limiting factor
Any biotic or abiotic factor that restricts the numbers, reproduction or distribution of organisms.

5. Food Water Space Disease Predation Shelter Nesting sites
Examples include:
Food
Water
Space
Disease
Predation
Shelter
Nesting sites
Atmosphere (temp)

10. Range of Tolerance
the upper and lower limits of what an organism can survive!
Temperature
pH (acidic or basic)
oxygen

13. Would an organism with a wide or narrow range of tolerance be more likely to survive better when abiotic factors are greatly changed?

14. ecological succession
The change in an ecosystem that happens when one community replaces another as a result of changing abiotic or biotic factors.

15. primary succession
The establishment of a community on an area of exposed rock that does not have top soil.

16. Usually starts with lichens and mosses that break down rock.
Volcanic areas!
These pioneer organisms produce dead decaying material to help create soil.

17. Lichen = a combination of fungus and algae

18. A seedling saltbush pioneers volcanic cinders
Sagebrush and a single pine colonize the cinder barrens left from an eruption

20. Primary succession

21. Secondary succession (not after primary, after an event that changes the ecosystem!)
The change that takes place after a community has been removed but the soil has remained intact from an event such as fire, flood or windstorm.
Pioneer species are the first to grow in this process . These are different from primary pioneer species. It is faster because soil is already present.

22. Example of secondary succession.

23. Secondary succession

24. Climax community
A mature community that results when there is little change in the composition of species.
The end result of primary succession.

25. Desert Climax Community

26. Rainforest

27. Arctic tundra

28. Disturbances in a community:
Fire
Flood
Windstorm
Hurricane
Landslide

29. Lake Eyre Basin Australia
Following periodic heavy rainful, the natural-flowing rivers that make up the region overfill with water and travel thousands of miles
inland to the lowest part of the continent, Lake Eyre basin. What happens next is a marvel of nature.
The basin–covering one-sixth of the continent–collects water flowing from these rivers, particular the three largest—Cooper Creek,
Diamantina and Georgina rivers. The water in turn awakens dormant wildlife and attracts water birds from across the country to
breed and feed.

31. Human Impact??

33. Tree Harvesting

34. Replanting after tree harvesting.

35. Biomes
A large group of ecosystems that share the same climate and have similar types of plant communities. (9 -10)
These are determined by latitude and climate.
Generally found at the same latitude and altitude.

36. Latitude
The distance of any point on the surface of Earth north or south of the equator.

37. As you go to higher latitudes the temperature decreases due to the decrease in the sun’s intensity this is due to the curvature of the earth.

38. Climate
The average weather conditions in an area including temperature and precipitation.
Factors affecting climate:
Latitude
Proximity to water
Shape of land (topography)
Direction of prevailing winds (Jet Stream)

39. 3 climate zones: polar, temperate, tropical

40. Proximity to water can affect climate:
City B is closer to a large body of water.
Its temperature line is flatter (moderated).

41. What factors determine the 9 biomes
What factors determine the 9 biomes? Defined primarily according in the characteristics of their plants and animals. These are determined by latitude and climate!

42. Terrestrial Biome = on land

43. Tundra: treeless, permanently frozen soil permafrost.

44. Boreal Forest: evergreens coniferous forest, taiga.

45. Temperate Forest: deciduous trees, 4 seasons

46. Temperate woodland: mixed shrubs, less rainfall

47. Temperate grassland: fertile soil, drought, prevents large trees

48. Desert: rate of evaporation exceeds rate of precipitation, on every continent except Europe

49. Tropical Savanna: grasses, scattered trees, low precipitation

50. Tropical seasonal forest: dry, trees drop leaves to conserve water

51. Tropical Rain Forest: Large amounts of rainfall, tall broad leaved trees.

52. end

53. Aquatic Ecosystems (3) Grouped based on abiotic factors: Water flow
Depth (related to light)
Distance from shore
Salinity
Latitude

54. 1. Freshwater Ecosystems
Ponds, lakes, streams, rivers, and wetlands
Low salt content
2.5 % water on earth is freshwater
Almost 70% of fresh water is frozen in glaciers.

55. Lakes are divided into zones:
Littoral zone: shallow near the shore, allows sunlight to penetrate through.
Limnetic zone: open water: plankton free floating
Profundal zone: deepest part, no light

56. Lake Zones

57. 2. Transitional Aquatic Ecosystems
Transitional = where land and water meet or where salt and fresh water meet
Wetlands: marshes, swamps, bogs
Estuaries: transitional very diverse, freshwater and saltwater mix.

59. A bog!

60. 2,400 yrs old

62. Apalachicola Estuary
Estuaries: transitional very diverse, freshwater and saltwater mix.

63. 3. Marine Ecosystems Intertidal: where ocean meets land
Photic: a zone in the ocean water to a depth of about 200 meters also called the euphotic zone, the area shallow enough for sunlight to penetrate!
Large numbers of organisms can be found in the photic zone!

65. Phytoplankton (plants) Zooplankton (animals) Fish Turtles Jellyfish
What lives in the photic zone?
Phytoplankton (plants)
Zooplankton (animals)
Fish
Turtles
Jellyfish
Dolphins
??????

67. Phytoplankton

68. Zooplankton

69. Basking shark

71. Aphotic: Below the photic zone, sunlight can not penetrate!
Benthic: on the ocean floor.
Abyssal: deepest part of the ocean
These categories are based on the depth of the ocean.

72. Know these zones! Be able to label them!!!!

73. What lives in the aphotic zone?
Octopus
Eels
Angler Fish
Hagfish
Squid
***The cold, deep water has more nutrients. Why? Things die and sink!

75. Hydrothermal tube worm