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Terrestrial Biomes _ Aquatic Ecosystems

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									Terrestrial Biomes &
Aquatic Ecosystems
Human-classified divisions
  Same types of climates = similar types of vegetation
  Similar vegetation = similar biome
  ≠ exact same flora, fauna, or physical abiotic makeup

Terrestrial Ecosystems or Biomes
  10 Types
Aquatic Ecosystems
  3 types
Terrestrial Biomes
 Large area characterized by its climate and the
 plants and animals that live in the area – contains
 related ecosystems.

 Tundra                        Chaparral
 Polar Ice                     Temperate Grassland
 Taiga/Coniferous Forests      Savanna
 Mountainous regions           Desert
 Temperate Deciduous Forest
 Tropical Rainforest
Tundra (Polar and Alpine)
 Tundra = “treeless plain”
   Flat terrain with low shrubs, grasses, sedge,
   mosses, lichens; low biodiversity
 One-fourth of Earth’s terrestrial surface
 Present in northernmost latitudes (≥ 60° N)
 Desert-like rainfall (30-50 cm or 12-20 in
 per year) but bogs and marshes in summer
 rainy season due to permafrost
Tundra (cont’d)
 Permafrost – condition of permanent
 frozen soil beginning ~ 1 meter (m) below
 surface and extending down to 500 m
   Water can not drain
 Plants produce in short 50-day season
 Year-round: Arctic lemmings, hares, foxes
 Summer migratory animals seeking food
 No reptiles or amphibians
 Also known as the Boreal or northern forests –
 covered with coniferous trees such as firs, pines,
 spruces, and cedars (dominant vegetation) –
 located south of tundra
 Largest biome on Earth; low biodiversity
 Winters: very cold and snowy
 Summers: warm, rainy, and humid
 Large mammals, fur-bearing animals
 Very few reptiles and amphibians
Deciduous Forest
 Temperate Deciduous Forest
Majority of eastern US, as well as continental western
Europe and east Asia
Deciduous trees (with seasonal leaf loss) including
maples, beeches, oaks, and hickories, as well as
understory of woody shrubs and vines and
herbaceous plants
Much precipitation (75 to 200 cm /yr) (3-8x that of
Milder winters, warm to hot summers
Great variety of animals, including reptiles and
Temp. Deciduous Forest (cont’d)
 Abundance of pines (evergreens) in the SE
 US is only temporary
 “Succession” – as ecosystem “ages,” new
 flora species replace previous ones (e.g.,
 grass to low shrubs and vines to evergreens
 to hardwoods); as flora change so will fauna
 Here, climax successional stage is
 oak/hickory forest
Temperate Grassland
Temperate Grassland
 Areas of predominantly tall, mixed, or short
 grasses sandwiched between temperate
 deciduous forests and deserts
 Annual precipitation of 25-100 cm
 Extremely fertile soil (US Midwest farms)
 Natural grasslands destroyed for
 agriculture; very little left in world
 Short grass prairie – crops and cattle
 Subtype of grassland: tropical grassland in
 Southern Hemisphere (Africa, South
 America, and Australia)
 Seasonal drought, warm climate, dotted
 with stands of trees, and home to typical
 large mammals (e.g. in Africa, elephants,
 giraffes, zebras, lions, spring boks, cape
 buffalo, etc.)
Desert: “Got Water?”
 Desert – area receiving < 25 cm annual
 precipitation; evaporation > precipitation
 Deserts may be cold, temperate, or hot
 Flora and fauna specialized to survive with little
 water – collect and conserve
 Soils poor because lack of water = very little
 biomass, or net productivity, low organics =
 inability to hold water
 Concentration of inorganic salts high
Tropical Rainforest
Tropical Rainforest
 Large warm equatorial areas, abundant
 annual precipitation (200-450 cm and even
 to 1000 cm for some) with high biomass
 productivity and biodiversity
 7% of Earth’s land mass under massive
 destruction; can not be replaced
 Poor, acidic soil: plants uptake quickly-
 decomposed organic nutrients
Polar Ice and Mountains
 Polar Regions:
   Cold, dry, devoid of terrestrial plant life
   Animals capable of living in frigid conditions
   and basis of survival on highly productive
   marine ecosystem
   Increase in altitude similar to northern latitudes
   (cooler climate and conifers)
   Rain shadow on lee side (desert area)
 Not a grassland
 Punctuated with low-
 growing evergreen shrubs,
 pines, and scrub oaks
 Lands on Western coast
 lines with Mediterranean
 type climate (wet mild
 winter/ hot dry summer,
 ocean winds)
Biome Ecological Concerns
 Tundra/Taiga– ore mining, oil drilling, ecosystem
 fragmentation, global warming/species changes
 Temperate Deciduous Forests – human destruction
 for resources and population
 Temperate Grasslands – very little remaining,
 non-native grass species; agriculture
 Deserts – In US, human encroachment
 Tropical Rain Forests - human destruction for
 resources and population; expansive loss of
 species, biomass net productivity
   Aquatic Ecosystems
     Intertidal Areas
     Coral Reefs
     Estuaries – fresh water from
     streams and rivers spills into
     Sargasso Sea (middle of Atlantic
     Ocean – floating rafts of algae
     called sargassum)
     Polar Ice – Arctic Ocean and
     ocean around Antarctica
     Stream and River; Pond and Lake
     Marshes and Swamps
   Marine Ecosystems
                            Photic zone = surface to
                            100 m down;
                            photosynthesis occurs

oceans cover
¾ of Earth’s
               Fig. 32.34
Marine Ecosystems, cont.
• Intertidal Zone: the place where the ocean meets the land;
area is exposed to the air for part of the day; sea grasses,
periwinkle snails, and herons are common in intertidal
mudflat; sea stars and anemones live on rocky shores; clams,
crabs, snails, and conchs are common on sandy beaches
•Neritic Zone: Ocean floor starts to slope downward as you
move away from shore; water is warm and receives a lot of
sunlight; plankton and seaweeds common; sea turtles,
dolphins, corals, sponges, and colorful fishes dominate –
Marine Ecosystems, cont.
•Oceanic Zone: Sea floor drops sharply; contains deep water
of open ocean; many unusual animals are adapted to this
zone, such as whales, squids, fishes that glow, sharks, etc.
•Benthic Zone: Ocean floor; deepest parts do not get any
sunlight and are very cold; animals, such as fishes, worms,
sea urchins, and crabs, have special adaptations to the deep,
dark water
Marine Ecosystem
  Coastal point of contact between freshwater and
  saltwater; mix = “brackish” water
  Constant mixing stirs up nutrients for
  photosynthesizers; animal life abundant
  As productive as tropical rainforests and coral
     Although protected, human pollution and encroachment
     threaten health of estuaries
Marine cont’d
 Abundance of life is generally greater:

   Nearer coast (intertidal zone) due to stirring action of
   waves and nearer surface from light

    In polar regions rather than tropical regions
   (abundant food – plankton - for large organisms)

   In tropical coral reefs along shallow coastlines
Marine cont’d
 Ecological Concerns:
   Overfishing and industrial fishing techniques
   that destroy deep water habitats
   Human pollution of the coastal waters (sewage,
   construction erosion, chemical use, etc.)
   Human physical destruction of sensitive
   ecosystems such as coral reefs, tidal pools
   Freshwater Ecosystems

Inland freshwater
streams, ponds, and
lakes cover 2.1% of
Earth’s surface.
Freshwater Ecosystems
Littoral Zone - area of water closest to edge of lake or
pond; cattails, rushes, algae, water lilies; small animals,
snails, insects, clams, worms, frogs, salamanders,
turtles, fish, and snakes
Open-Water Zone – the zone of a pond or lake that
extends from the littoral zone and that is only as deep
as light can reach – bass, lake trout, and other fishes
Deep-Water Zone – the zone of a lake or pond below
the open-water zone, where no light reaches – carp,
catfish, worms, crustaceans, fungi, and bacteria
Freshwater cont’d
 Natural lake nutrient concentrations
 (phosphorus often is limiting factor)
   Shallow, nutrient rich = eutrophic
    • Abundant aquatic photosynthesis and animals
      (cloudy, murky water)
    • Occurs naturally over long periods of time
   Deeper, nutrient poor = oligotrophic
    • Few nutrients to aid photosynthesis, little animal life
      (clear water)
Freshwater Concerns
 Artificial eutrophication of lakes: nutrient rich
 sewage, fertilizers, construction erosion, etc. feed
     Algal bloom leads to accumulation of dead algae;
     decomposition by oxygen-using bacteria; fish kills
 Clean Water Act has helped, but battle not over
 (Pollutants regulated under the CWA include "priority" pollutants,
 including various toxic pollutants; "conventional" pollutants, such as
 biochemical oxygen demand (BOD), total suspended solids (TSS),
 fecal coliform, oil and grease, and pH; and "non-conventional"
 pollutants, including any pollutant not identified as either conventional
 or priority. The CWA regulates both direct and indirect discharges. )
 Land remaining wet for at least part of the year (bog,
 marsh, swamp, tidal marshes) and very productive
 Most are inland, freshwater
 Soils and plants can capture pollutants, act as wastewater
 system and clean up
 Play important role in flood control
    Federal protection requires restoration, but many destroyed
    Loss of migratory bird habitat
Marshes and Swamps
   Treeless wetland ecosystem where plants grow; found
   in shallow areas along shores of lakes, ponds, rivers,
   and streams; grasses, reeds, bulrushes, wild rice,
   muskrats, turtles, frogs, and birds dominate

   Wetland ecosystem in which trees and vines grow;
   found in low-lying areas and beside slow-moving
   rivers; flooded part of the year; willows, bald cypresses,
   oaks, poison ivy, water lilies, orchids, fish, snakes, and
   birds dominate

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