1. CHAPTER 4 SECTION 3 SC B-6: STUDENTS WILL DEMONSTRATE AN UNDERSTANDING OF THE INTERRELATIONSHIPS AMONG ORGANISMS & THE BIOTIC & ABIOTIC COMPONENTS OF THEIR ENVIRONMENT BIOMES

2. Biomes major life zones characterized by vegetation type (in terrestrial biomes) or by the physical environment (in aquatic biomes)

3. Climograph plot of annual mean temperature & precipitation in a particular region

4. Climographs show that temp & precipitation are correlated with biomes because other factors also play a role in biome location: biomes can overlap

5. Climograph for Some Major Biomes

6. General Features of Terrestrial Biomes most named for major physical or climatic features & for their predominant vegetation each biome also characterized by: microorganisms fungi animals all adapted to that particular environment

7. Biome Species Composition varies w/in each biome  ex: eastern part of one large lake may have different water bird than western portion

8. Tropical Forest Distribution: equatorial & subequatorial Precipitation:  Tropical Rainforest: constant, 200 -400 cm/yr  Tropical Dry Forest: seasonal, 150 – 200 cm/yr Temperature:  high all yr, average 25 – 29°C, little seasonal variation

9. Tropical Forest

10. Tropical Forest: Plants vertically layered intense competition for light

11. Tropical Forest Plants Tropical Rainforest  see all layers, some with 2 layers of subcanopy trees  broadleaf evergreen trees dominate  epiphytes (air plants) & orchids typically cover trees Tropical Dry Forest  see fewer layers  drop leaves during dry season  commonly have thorny shrubs & succulent plants

12. Tropical Forest: Animals millions of species 5 – 30 million undiscovered species of insects, spiders, other arthropods highest animal diversity than anywhere else on Earth all adapted to vertically layered environment

13. DESERT Distribution:  occur in bands near 30° N & S latitude or in interior of continents Precipitation:  low & variable; <30 cm/yr Temperature :  variable seasonally & daily  hot desert: max T may > 50°C  dry desert: low T may < -30°C

15. Deserts

16. Desert Plants see low, widely scattered vegetation  see more bare ground than other terrestrial biomes succulents  cacti  euphorbs deeply rooted shrubs & herbs  grow during brief rainy periods

17. Desert Plants Adaptations:  heat & desiccation tolerance  water storage  reduced leaf surface area  CAM photosynthesis  physical defenses:  spines  chemical defenses:  toxins in leaves of shrubs

18. Desert Animals Common animals: Snakes Lizards Scorpions Ants Beetles Birds: migratory & resident seed-eating Rodents

19. Desert Animal Adaptations many species are nocturnal water conserved in variety of ways:  only water some get is by metabolizing carbohydrates  water + carbon dioxide

20. SAVANNA Distribution:  equatorial & subequatorial Precipitation:  seasonal rainfall 30 – 50 cm/yr  dry season can last 8 – 9 months Temperature :  warm year-round: 24 – 29 °C  more seasonal variation than tropical forests

21. Savanna Distribution

22. Savanna

23. Savanna Animals dominant herbivores are insects  especially termites large herbivores migrate toward thicker vegetation & watering holes during dry season

24. Chaparral also called  mattoral (Spain & Chile )  garigue & maquis (southern France)  fynbos (South Africa)

25. Chaparral Distribution:  midlatitude coastal regions Precipitation:  highly seasonal (rainy winters, dry summers)  averages 30 – 50 cm/yr Temperature :  fall, winter, spring are cool (10 – 12°C)  summer can get > 40°C

26. Chaparral Distribution

27. Chaparral

28. Chaparral Plants dominated by shrubs, small trees, variety of grasses & herbs plant diversity high though some species found only in very limited areas adaptations to:  drought: tough evergreen leaves  fire:  herb seeds only germinate after hot fire  roots are fire resistant (plants re-sprout quickly)

29. Chaparral Animals natives include:  browsers (deer, goats)  high diversity of small mammals  many amphibians, birds, reptiles, insects

30. Temperate Grassland also called: veldts (South Africa) puszta (Hungary) pampas (Argentina & Uruguay) steppes (Russia) plains & prairies (North America)

31. Temperate Grasslands

32. Temperate Grassland Precipitation:  highly seasonal: dry winters/wet summers  averages vary between 30 – 100 cm/yr  periodic drought is common Temperature :  winters cold (< -10°C)  summers moderately hot ( 30°C)

33. Temperate Grasslands

34. Temperate Grasslands: Plants dominant plants are grasses & forbs  some grasses 2 m high many adapted to survive periodic drought & fires grazing by herbivores helps prevent establishment of woody plants

35. Temperate Grasslands: Animals native mammals  large: bison, wild horses  small burrowers: prairie dogs

36. Northern Coniferous Forest aka: taiga Distribution:  broad band across northern North America & Eurasia to edge of arctic tundra Precipitation:  30 – 70 cm/yr  periodic droughts are common Temperature :  winters cold (-50°C in Siberia)  summers usually >20°C

37. Northern Coniferous Forest aka: taiga Distribution:  broad band across northern North America & Eurasia to edge of arctic tundra Precipitation:  30 – 70 cm/yr  periodic droughts are common Temperature :  winters cold (-50°C in Siberia)  summers usually >20°C

38. Northern Coniferous Forest

39. Northern Coniferous Forest: Plants

40. Northern Coniferous Forest: Animals Birds: residents & summer migrants insects occasionally kill large tracts of trees Mammals:  Moose  Brown Bear  Siberian Tiger

41. Temperate Broadleaf Forest Distribution mainly in midlatitudes of northern hemisphere  smaller areas in Chile, South Africa, Australia, New Zealand

42. Temperate Broadleaf Forest Precipitation:  70 to > 200 cm/yr (includes snow)  all seasons have precipitation Temperature :  winter averages ~ 0°C  summers hot & humid/ up to 35°C

43. Temperate Broadleaf Forest

44. Temperate Broadleaf Forest: Plants mature forest has distinct vertical layers including a closed canopy dominant plants in North America are deciduous trees  adaptation: drop leaves as weather gets colder: uptake of water by roots not feasible when soil frozen dominant plant in Australia: Eucalyptus

46. Temperate Broadleaf Forest: Animals mammals, birds, insects make use of vertical layers many mammals hibernate in winter many birds (and some butterflies) migrate south

47. Tundra Distribution:  covers arctic: 20% Earth’s land surface  tops of high mountains Precipitation:  20 – 60 cm/yr in arctic tundra  >100 cm/yr alpine tundra Temperature:  winter averages < -30°C  summer averages < 10°C

48. Tundra

49. Tundra: Plants mostly herbaceous:  mosses, grasses, forbs + dwarf shrubs & trees, lichens  permafrost (frozen ground year round) prohibits growth of plant roots

50. Tundra: Animals Birds: migratory, arriving for nesting in summer Mammals:  Residents: musk ox  Migrators: caribou, reindeer  Predators: bears, wolves, foxes