The Biosphere

1
The Biosphere

• Starr/Taggarts
• Biology
• The Unity and Diversity of Life

2
Key Concepts

• Energy from the sun is the initial energy source
  for nearly all ecosystems
• Solar energy influences the global distribution
  of ecosystems
• Interactions among global air circulation
  patterns, ocean currents, and topographic
  features result in regional variations in
  patterns of temperature and rainfall

3
Key Concepts

• A biome is a large unit of land that is
  characterized by climax vegetation of the
  ecosystem in its boundaries
• Water covers more than 71 of the earths surface
• Freshwater and marine ecosystems have gradients
  in light availability, temperature, and dissolved
  gases

4
Global Air Circulation Patterns
Equatorial air rises and spreads north and south
5
World Temperate Zones
6
Ocean Currents

• 71 of earths surface is covered by water
• Latitudinal and seasonal variations in solar
  heating
• Surface waters move from equators to poles
• Trade winds and westerlies
• Earths rotation
• Clockwise rotation - Northern hemisphere
• Counterclockwise - Southern hemisphere
• Position of land masses and shape of ocean basins

7
Sea Breezes Along Coastlines
Afternoon
Night
8
Biogeographic Distribution

• Biogeographical Realms
• Tundra
• Evergreen Coniferous forest
• Temperate Deciduous forest
• Temperate grassland
• Dry woodland
• Desert

9
Soil

• Mixture of minerals and decomposing organic
  materials (humus)
• Profile
• Uppermost (topsoil)
• Humus
• Vulnerable to erosion
• Variable in all realms
• Lower
• Rocks in degrees of erosion
• Clays

10
Deserts

• Lands with lt 10 cm of annual rainfall
• High evaporation
• Low humidity
• Biodiverse
• More than 1/3 of all land surface
• Arid or semiarid
• Desertification

11
Dry Shrublands, Woodlands and Grasslands

• Periods of drought and fires
• More rain than deserts
• Drought-tolerant plants
• Hot summers, cold winters
• Chaparral
• Savannas
• Grazing animals

12
Tropical Rain Forests and Broadleaf Forests

• Canopy Trees
• Evergreen Broadleafs
• Tropical rain forests
• Rapid decomposition and mineral cycling
• Humus poor
• Deciduous Broadleafs
• Leaves drop
• Tropical and Temperate Forests
• Decomposition not as rapid

13
Forests

• Canopy Trees
• Evergreen Conifers
• Needle-shaped leaves
• Boreal forests
• Montane Coniferous forests
• Temperate Rain forests
• Pine barrens

14
Tundra

• Treeless plain between polar ice cap and boreal
  forests
• Flat, windswept, wet
• Cool short summers
• Below freezing winters
• Sunlight nearly continuous in summers
• Permafrost

15
Freshwater Provinces

• Lakes
• Rivers
• Ponds
• Estuaries
• Wetlands

• Rocky and sandy shores
• Coral Reefs
• Parts of ocean
• Hydrothermal vents

16
Lake Ecosystems

• Standing freshwater

17
Seasonal Changes in Lakes

• Changes in density and temperature
• Spring overturn
• Fall overturn

18
Trophic Nature of Lakes and Streams

• Oligotrophic
• Eutrophic
• Member residents determined by
• Topography
• Climate
• Geologic history

19
Stream Ecosystems

• Flowing water
• Starts as freshwater springs
• Grow and merge
• Downslope flow
• May combine to form river
• Flow Influence
• Rainfall, snowmelt, geography
• Streambed Composition
• Agricultural, Industrial, Urban waste

20
Primary Productivity in the Ocean

• Surface
• Photosynthesis by phytoplankton
• Ultraplankton
• Hydrothermal vents in ocean floor

21
Seasonal Variation in Primary Production in Oceans

• Phytoplankton blooms

22
Coral Reefs and Banks

• Fringing reefs
• Barrier reefs
• Atolls
• Coral banks
• Dinoflagellates as symbionts

23
Life Along the Coasts

• Estuary
• Seawater mixes with freshwater
• Salt marshes
• Bay areas
• Intertidal zone
• Rocky and sandy
• Waves
• Alternating tides expose areas
• Upper littoral, midlittoral, lower littoral

24
Upwelling Along Coasts

• Northern hemisphere

25
In Conclusion

• Energy flows one way through the biosphere
• Distribution of species through the biosphere is
  an outcome of topography, history, climate, and
  interactions among species
• Climate refers to weather conditions resulting
  from solar radiation, earths movement, and
  distribution of geography

26
In Conclusion

• Climatic factors produce winds and ocean currents
  which shape global weather patterns
• The Earths land masses are classified as six
  major biogeographical realms
• A biome is shaped by regional variations in
  climate, landforms, and soil composition

27
In Conclusion

• Water covers more than 71 of earths surface
• Photosynthetic activity is greatest in shallow
  coastal waters and in regions of upwelling
• There is an interrelatedness of ocean surface
  temperatures, the atmosphere, and land
• developed by M. Roig