Communities and Biomes

1
Communities and Biomes
2
Community

• Collection of several interacting populations
  that inhabiting a common environment.

3
Abiotic factors and biotic factors determine an
organisms ability to survive
4
Limiting Factors

• Environmental factors that affect the organisms
  ability to survive in its environment.
• (food availability, temperature, and predators)

5
Limiting Factors

• Biotic or abiotic
• Restrict existence, numbers, reproduction or
  distribution of an organism.
• Factors that limit one population in a community,
  may indirectly effect another
• E.g. Lack of water limits grass growthreducing
  seed growth, mice need seeds for food, no food,
  populations reduce.

6
Ranges of Tolerance

• Organisms ability to withstand fluctuations in
  biotic and abiotic environmental factors
• Populations varies according to its tolerance for
  environmental changes.

7
(No Transcript)
8
Succession

• Orderly, natural changes and species replacements
  that take place in communities over time.

9
Succession

• Occur in stages different species at different
  stages create conditions that are suitable for
  some organisms and not suitable for others.
• Difficult to observe happen over long periods of
  time.

10
Primary Succession Initial colonization of new
sites

• Lava from volcano Avalanche
• Pioneer speciesFirst species in the area (e.g.
  Lichen)
• Climax CommunityA stable, mature community that
  undergoes little or no change in species.
• Over time as a community or organisms change and
  develop (additional habitats emerge, new species
  move in, and old species disappear) Areas become
  forest of vines, trees, and shrubs, inhabited by
  birds and other forest-dwelling animals.
• Gradual changes over time.

11
(No Transcript)
12
Pioneer species colonize
Growth continues until community becomes
fairly stable.
Pioneering organism dies, decaying into soil.
Presence of soil makes it possible for weedy
plants, small ferns, and insects to become
established
Soil builds up, seeds borne by wind blow into
soil, and begin to grow
Area becomes forest of vines, trees, and
shrubs. Birds and other animals.
13
Secondary Succession

• Sequence of changes that take place after a
  community is disrupted by natural disaster or
  human actions.

14
Secondary Succession

• Gradual changes over time
• Area previously contained life
• Land that contains SOIL
• Different pioneer species
• May have same climax community, with similar
  climate.
• Faster to develop because soil exist.

15
(No Transcript)
16
Biomes Large areas that have characteristics of
climax communities
17
Biome Factors

• Altitude and Latitude
• Temperature and Precipitation
• Major limiting factors

18
Biomes

• Aquatic BiomesMarine, Freshwater, Estuaries (3/4
  of Earths surface covered by aquatic biomes)
• Terrestrial BiomesTundra, Taiga, Desert,
  Grassland, Deciduous Forest, Tropical Rain Forest.

19
(No Transcript)
20
(No Transcript)
21
Marine Biomes

• Oceans
• Photic ZonePortion of marine biome that is
  shallow enough to penetrate sunlight
  (coastlines-Shore, beaches, mudflats)
• Aphotic ZoneDeeper waters that do not receive
  sunlight. (Deep, least explored oceans)
• PhosLight (Greek)
• Awithout (Greek)

22
(No Transcript)
23
Marine Life

• Largest amounts of biomass (living materials)
  though often very small
• Whales, seals, sea otters, sea cows
• Kelp, algae, sea grass

24
(No Transcript)
25
(No Transcript)
26
Estuary

• Bay, sound, fjord, salt marshes, wetlands
• Freshwater mixes with salt water (some land)
• Brackish Water ( more salt than freshwater but
  less than marine)
• Salinity ranges
• Amount of freshwater vs.. Saltwater
• Tides
• Biodiversity

27
Estuary Life

• Eelgrass, smooth cordgrass, sea lavender
• Shiner Perch, Starry Flounder Orange Striped
  Jellyfish, Purple Shore Crab, Scallop
• Predatorscranes and other birds
• Decay of dead organisms is quick, nutrients
  recycled through food web.

28
(No Transcript)
29
Tides Gravitational pull of sun and moon cause
the rise and fall of ocean tides.
30
Intertidal zonePortion of the shoreline that
lies between the high and low tide lines

• Size depends on slope of the land and tide
  height.
• High levels of sunlight, nutrients and oxygen
  (But productivity may be limited by waves/tides)
• Differ in rockiness and wave actions
• Snails, sea stars, mussels, barnacles, clams,
  worms, crabs

31
Tide Pools Pools of water left when the water
recedes at low tide, can land lock organisms
until next tide. Vary greatly in nutrient and
oxygen levels
32
(No Transcript)
33
Ocean Bottom/Photic Zone

• Less affected by waves and tides
• Nutrients washed from the land by rainfall
  contribute to abundant life and high
  productivity.
• PlanktonSmall organisms that live in waters of
  photic zone.removal great impact
• Autotrophsdiatoms
• Heterotrophesjuvenile stages of many marine
  animals.

34
Ocean Bottom/Aphotic Zone

• Almost 90 of ocean is gt than a km deep.
• Animals living there far and few, depend on
  photic zone where plankton live for food
  (directly or indirectly)
• Fish adapted to darkness and scarcity of food

35
(No Transcript)
36
Freshwater Biomes

• Major abiotic factors temperature and light
• Not enough sunlight penetrates to bottom to
  support photosynthesis
• few aquatic plants or algae grow
• Population density lower
• Bacteria break down dead organisms and recycle
  nutrients.

37
Freshwater Life

• Concentric bands of species
• Cattails, sedges
• Tadpoles, aquatic insects, turtles, worms,
  crayfish, beetles, dragonflies, minnows,
  bluegill, carp.

38
(No Transcript)
39
Terrestrial Biomes
40
(No Transcript)
41
Tundra

• Treeless land long summer days short periods of
  winter sunlight
• Temperatures never rise above freezing

42
Permafrost

• Underneath topsoil is a layer of permanently
  frozen ground. (Mammoths)

http//news.bbc.co.uk/2/hi/science/nature/6284214.
stm
43
Tundra Organisms

• Shallow-rooted grasses (sedges), small plants,
  reindeer moss (lichen)
• Soil lacking in nutrients decay process slow due
  to cold temperatures.
• Mosquitoes, lemmings, weasels, artic foxes,
  snowshoe hares, musk oxen, caribou, reindeer.

44
(No Transcript)
45
Taiga/Boreal Forest

• South of tundra
• Warmer and wetter than tundra
• Climatic conditionslong, severe winters, short,
  mild summers.
• Canada, Northern Europe, Asia.
• Permafrost absent
• Topsoildecaying coniferous needles
  Pines/evergreens (acidic and poor in minerals)

46
Taiga Organisms

• PLANTS
• Northern coniferous (cone bearing) forest
• Larch, fir, hemlock, spruce trees
• Fire/Logging disrupts taiga-first trees to
  re-colonize are birch, aspen, or other deciduous
  species.
• ANIMALS
• Raccoons, bears, lynxes, wolves, ruff-legged
  buzzards, caribou, ox, artic fox

47
(No Transcript)
48
Desert

• Arid region
• Sparse to almost nonexistent plant life
• Less than 25 cm of precipitation annually
• Atacama Desert (Chile)one of dryest places in
  the world.

49
Desert Organisms

• PLANTS
• Drought-resistant treesmesquites, cacti,
  creosote bush
• ANIMALS
• Lizards, tortoises, snake, coyotes, hawks, owls,
  roadrunners, scorpions.

50
(No Transcript)
51
Grasslands/Prairies/Steppes/Pampas/Savannas

• Large communities covered by grasses and similar
  small plants
• Yellowstone National Park
• Fewer than 10 to 15 trees per HECTARE!
• (a unit of surface, or land, measure equal to
  100 areas, or 10,000 square meters equivalent to
  2.471 acres-www.dictionary.com)
• Most terrestrial area
• Higher biological diversity than desertmore than
  100 species per acre.

52
Species

• Animals herd animals, fox, prairie dogs,
  coyotes, weasels, Red-tailed Hawks, bison, lions,
  antelope and lynx.
• Plants buffalo grass, ryegrass, foxtail, wild
  oats, and purple needlegrass
• Wildflowers wild indigos, clovers, sunflowers,
  goldenrods, blazing stars, and asters

53
(No Transcript)
54
Temperate Forests

• Many types
• Precipitation 70 to 150 cm annually
• Dominated by broad-leaved Hardwood tress that
  lose their foliage annually.
• Soiltop layer rich in humus and deep layer of
  clay.
• AnimalsBlack bears, deer, squirrels,
  salamanders, mice, blue jays
• Plantsbirch, hickory, oak, beech and maple.

55
Tropical Rain Forest

• More species of organisms anywhere
• Warm temperatures (25?C), high humidity, and
  abundant rain fall, lush plant growth
• Biodiversity makes important protect
• Near equator
• Precipitation 200 cm annually (some 600 cm)

56
Why so many species in rain forest? Hypothesis

• Location near equatornot covered with ice during
  last ice agemore time to evolve
• Warm weather, do not drop leaves, year round
  growing conditions for plants, creates greater
  food supply, therefore supports more organisms.
• Provide a multitude of possible habitats for
  diverse organisms.
• More layers allowing more for organisms to exist.
  (Many organisms find their niche)

57
Tropical Rain Forest Continued

• Nutrients are tied up in living materials (few
  soil)
• Decomposers do their work
• Rainforest trees have roots and mycorrhizae that
  enable them to absorb nutrients.
• Trees are cut for their hardwoods (mahogany), for
  farming, and to produce grasslands for cattle.

58
(No Transcript)
59
Layers of the Rain Forests
60
EMERGENT LAYER

• Highest layer.
• Tallest trees.
• Resemble umbrellas
• Researcher built towers and aerial walkways in
  the trees.
• Birds, butterflies and small monkeys live with
  bats, snakes and bugs.

61
Kapok Tree
Brazil Nut Tree
62
CANOPY

• Trees 25- 35 meters
• Only a few taller trees push to make the emergent
  layer
• Treetops stop a lot of the light from entering
  the forest.
• Protects the soil from erosion from rains.
• Birds, monkeys, frogs, and sloth, as well as
  lizards, snakes and many insects

63
Howler Monkey
Spider Monkey
64
Understory

• Trees that reach the canopy.
• Wait until a gap appears which they can then grow
  into.
• Small, thin trunks.
• 20 meters tall.
• This layer is the home to birds, butterflies,
  frogs and snakes.

65
hummingbirds
66
SHRUB LAYER

• Grows between the smaller trees of the understory
  and the forest floor.
• ferns and small shrubs

67
FOREST FLOOR

• Very dark (Estimated that only 2 of the sunlight
  actually reaches the floor)
• Layer of leaves, twigs and dead plants, which rot
  down quickly to provide nutrients for the plants
  (Home to invertebrates and microorganisms, which
  quickly rot down this surface layer)
• The soil is very sandy with only a thin layer of
  rotting vegetation. Without the trees, the soil
  quickly loses its ability to support plants and
  turns to desert-like conditions.

68
Rainforest floor Organisms

• PlantsFerns and Mosses
• Animalstigers and elephants in Asia, gorillas
  and leopards in Africa and tapirs and jaguars in
  South America.

69
Amazon River Dolphin
70
(No Transcript)