Assignment: Read Chapter 4:
Variations in the Physical Environment
Next week ONLY: Monday AM lab = Tues 5-8
Monday PM lab = Wed 5-8
Please turn cell phones off + put away.
1st row seats = saved for later-comers…
Biological Communities: The Biome Concept
OBJECTIVES
• What are large-scale distributions of plant
life forms?
•
aquatic
•
terrestrial
• What is the proximal cause of their
distribution?
• How does climate differ among biomes?
•
Whittaker’s scheme
•
Walter’s climagrams
• Do form and function converge in regions
with similar climate?
Concept Map…
*** Which physical factor separates habitats?
A
B
C
D
water availability
movement of water
medium of gas exchange
amount of salinity
USE EACH ONCE
Biome
1
Terrestrial
Aquatic
4
Wetlands
2
Desert
Freshwater
3
Rivers
Marine
Lakes
Aquatic habitats
River: where precipitation > evaporation
River continuum
Downstream drift
High gradient vs.
Low gradient
A lake can be divided into vertical and
horizontal zones.
photic
aphotic
Lakes can be poor or rich in nutrients.
Oligotrophic
Eutrophic
Limnology = study of freshwater habitats
Ocean zones differ in temperature, depth,
light, and tides.
Abyssal zone
Ocean
habitats
Oceanography
Marine biology
The terrestrial-aquatic interface…
Estuary:
where a
river
reaches the
ocean but is
impeded by
landforms
The terrestrial-aquatic interface
rocky
freshwater
estuary
woody herbaceous
woody
marine
herbaceous
swamp bog/fen marsh mangrove salt marsh
tropical
Another concept map…
temperate
Concept map
*** What 4 variables distinguish biomes?
Herbaceous/graminoids
Shrubs
(grasses, sedges)
Shrublands
Trees
Forests
Grasslands
Deserts
Tundra
Evergreen
Conifers
Deciduous
Broadleaf
Temperate
Temperate Trop.
Tropical
Biome: a major type of terrestrial community
categorized by its 1) dominant plant form, 2)
seasonality of leaves, 3) leaf morphology, 4) location.
***Review of major biomes…
(write these down)
Tropical rain forest
Tropical seasonal (deciduous) forest /
savanna
Subtropical desert
Woodland/shrubland
Temperate rain forest
Temperate seasonal (deciduous) forest
Temperate grassland
Boreal forest (taiga)
Tundra
***What
biomes do
you see in a
crosscountry trip
from E to W?
***Write down the letter that corresponds to
the name of the biome:
Pictures not in this PP…
go to book to see them.
Answers
A
B
C
D
E
F
G
H
Tropical rain forest
Tropical seasonal forest/savanna
Subtropical desert
Woodland/shrubland
Temperate rain forest
Temperate grassland/desert
Temperate seasonal forest
Boreal forest
Tundra
*** Which biome is found at each indicated
letter?
C
D
A
B
E
F
I
H
G
Answers
H Tropical rain forest
G Tropical seasonal forest/savanna
F Subtropical desert
D Woodland/shrubland
I Temperate rain forest
C Temperate seasonal forest
E Temperate grassland
B Boreal forest
A Tundra
***Proximate/functional approach…
• What is the major factor determining
biomes?
• In one sentence:
Why isn’t there a single biome for the
earth?
Most species have limited tolerance;
hence small ranges and biomes develop.
***In one sentence: Compare the ranges of birds/plants.
Climate is the major determinant of plant
distributions.
Other factors are soil, fire, grazing,
topography.
Whittaker’s scheme: biomes delineated
by average temperature and
precipitation.
Walter’s climate diagrams allow comparisons
among localities.
20 mm monthly rain
For each 10ºC in temp
= enough water for
growth
(wherever precip line
is above temp line)
growing season
What is clue that this is a desert?
Climatic zones and biomes separated first on basis of
temperature, then precipitation and its seasonality.
Boreal + polar climate zones:average annual T=< 5C
Temperate climate zones: average annual T = 5-20C
Equatorial + tropical climate zones: average T = > 20C.
Each climate zone has a typical
seasonal pattern of temperature and
precipitation.
When is its
dry season?
A
B
***What type of biome would you
expect to develop with each climate?
Explain.
A
B
***What type of vegetation would you
expect at each locality? Explain.
***Summarize in one sentence the main
conclusion about biomes based on these
figures and legends.
Localities worldwide with similar climate
have the same biome.
Observation:
Plant growth form is similar in widely
separated areas.
I wonder why?
Mexico
Kenya
***Hypothesis:
If form and function match the environment,
then…?
Prediction: then unrelated organisms in
similar environments will evolve similar form
and function = Convergent evolution
Mexico
Kenya
Unrelated African and South American
rainforest mammals show striking
convergence.
Example of exam question…
A. Which biome would occur in each climate?
B. What is the limiting climatic factor(s) for each
biome?
C. Where is each biome located in the Western
(New World) and Eastern (Old World)
hemisphere? Put letters on map.
OBJECTIVES
• What are large-scale distributions of plant
life forms?
•
aquatic
•
terrestrial
• What is the proximal cause of their
distribution?
• How does climate differ among biomes?
•
Whittaker’s scheme
•
Walter’s climagrams
• Do form and function converge in regions
with similar climate?
Vocabulary
Chapter 5 Biological Comm uniti es: The Biome Concep t
biomes*
ecological tolerance s
speciali zations
clim ate zone
steppes
taiga
emergen t trees
epiphytes
pools
autochthonou s
litt oral zone
estuar ies
neriti c
photic zone
growth form
edaphic
speciali sts
growing season
rhizomes
permafrost
unde rstory
streams
all ochthonou s
river continuu m
lim netic zone
litt oral zone
oceanic zon e
apho tic zone
forbs
optim um
gene rali sts
prairies
sclerophy ll ous
canopy
li ana s
riffles
riparian zone
lakes
benthic zone
zona tion
benthic zone
coral reefs
More vocabulary…Chaper 5/ Lecture 2:
lotic
herbaceous
continental drift
ecotone
cypress
marsh
oligotrophic
deep sea vent
community
lentic
graminoids
rain shadow
marine
mangrove
salt marsh
eutrophic
kelp forest
plant form
topography
midden
swamp
bog/fen
estuary
oxbow lake
inter-tidal
zone