environmental science chapter 6 and 7 communities, biomes, & population biology
TRANSCRIPT
Environmental science chapter 6
and 7
Environmental science chapter 6
and 7
Communities, Biomes, & Population
Biology
Communities, Biomes, & Population
Biology
I.I. Limiting Limiting FactorsFactors
- factors that affect an organism's ability to survive in its environment
- temperature, rainfall, fire, food, predators, etc.
A.A. Optimum Range:Optimum Range:- area with fewest limiting
factorsB.B. Range of Tolerance:Range of Tolerance:
- area with a few limiting factors
C.C. Zone of Stress:Zone of Stress:- area with several limiting factor
Optimum Optimum RangeRange
**
Range of ToleranceRange of Tolerance
Optimum RangeOptimum Range
Distribution Distribution ofof
Douglas-firDouglas-fir
MicroclimateMicroclimate
II.II. Ecological Ecological SuccessionSuccession
Mount St. HelensMount St. Helensexplosion, 1980explosion, 1980
Same view,Same view,20 years later20 years later
II.II. Ecological Ecological SuccessionSuccession
- the replacement of one community by another over time
- one community changes the physical environment so that it can't survive but another community can
A.A. Primary Succession:Primary Succession:- succession on land that has
not been previously occupied- ex. lava, ash, bare rock- Pioneer species: mosses,
lichen - build soil
Primary Primary SuccessionSuccession
Succession in a Succession in a PondPond(a)(a)
(b)(b)
(c)(c)
B. Secondary B. Secondary SuccessionSuccession- reestablishing an ecosystem
following disturbance- ex. mudslides, hurricanes,
flood, ‘cool’ fire, clearcutting, abandoned fields
Secondary Secondary SuccessionSuccession
C. Climax EcosystemC. Climax Ecosystem- a stable,
balanced community
C. Climax EcosystemC. Climax Ecosystem- occurs at the end of
succession- can regenerate itself
(plants can tolerate shade)
III.III. Biomes:Biomes:- a large group of ecosystems
with a characteristic climate and dominant plant life
A. Aquatic BiomesA. Aquatic Biomes- supports great variety of life- limiting factors: light, oxygen,
CO2, nutrients, temperature
1.1. Marine Biomes:Marine Biomes:- vast and varied habitats- light penetrates only 100 -
600 feet (photic zone)
MarinMarinee
BiomeBiomess
Photic Photic ZoneZone
Aphotic Aphotic ZoneZone
Intertidal Intertidal ZoneZone
Neritic Neritic ZoneZone
Open Open Ocean Ocean ZoneZone
Deep-Deep-Sea Sea
ZoneZone
a)a) Intertidal Zone:Intertidal Zone:- harsh
environment: tides, waves, exposure to air
b)b) Neritic Zone:Neritic Zone:- between low tide and open-sea- abundant nutrients- most productive marine environment
Kelp ForestKelp ForestCoral ReefCoral Reef
c)c) Open-Ocean Zone:Open-Ocean Zone:- low nutrients and fewer
living organisms
d)d) Benthic Zone:Benthic Zone:- extremely
harsh environment
- cold, dark, high pressure
‘Black Smoker’
‘Black Smoker’
d)d) Benthic Zone: Benthic Zone:- habitat for bizarre fish and
other animalsFangtoothFangtooth
Deep-sea AnglerfishDeep-sea Anglerfish
UmbrellamouthGulper
UmbrellamouthGulper
2.2. Estuaries:Estuaries:- boundary between fresh
and salt water
2.2. Estuaries:Estuaries:
- highly productive habitat for many animals
- abundant nutrients and light- "nursery" for many animals
- boundary between fresh and salt water
3.3. Freshwater Biomes:Freshwater Biomes:- rivers, lakes,
ponds, and groundwater
- < 1% of earth's water
- drinking water- dumping
ground for wastes
B.B. Terrestrial BiomesTerrestrial Biomes- most important limiting
factors are temperature and precipitation
Terrestrial BiomesTerrestrial Biomes
High
High
( (Temperature)
Temperature) Low
Low
High
High
( (Temperature)
Temperature) Low
Low
DryDry (Rainfall) (Rainfall) WetWetDryDry (Rainfall) (Rainfall) WetWet
Climate Affects Biome Climate Affects Biome DistributionDistribution
Effects of Elevation on Effects of Elevation on TemperatureTemperature
Low
Low (
( Altitude)
Altitude)
High
High
Low
Low (
( Altitude)
Altitude)
High
High
EquatorialEquatorial (Latitude) (Latitude) PolarPolarEquatorialEquatorial (Latitude) (Latitude) PolarPolar
Olympic/Cascade Rain Olympic/Cascade Rain ShadowShadow
WestWest EastEast
100100
5050
00
50005000
40004000
30003000
20002000
10001000
00
Average AnnualAverage AnnualPrecipitation (cm)Precipitation (cm)
Altitude (m)Altitude (m)
150150
Earth’s Curvature Earth’s Curvature and Tilt Make and Tilt Make
SeasonsSeasonsShort days;
Long nights;Winter
Long days;Short nights;
Summer
Air Currents & Climatic Air Currents & Climatic RegionsRegionsSaharan & Arabian deserts are @ 30° N
South African Desertis @ 30° S
Congo rain forest is @ 0°
1.1. TundraTundra
TundraTundraTreeless region < 10 in. rain annuallyPermanently frozen soil (permafrost)Very fragile, scars last for centuries
Tundra
Taiga
Deciduous Forest
Grassland
Desert
Tropical Rain Forest
TreelessShort Plants
Very cold/ Brief summer< 10” Precip. / Permafrost
BiomeBiome ClimateClimate Dominant Dominant PlantsPlants
2.2. TaigaTaiga
TaigaTaiga(Northern Coniferous (Northern Coniferous
Forest)Forest)Northern Canada and Eurasia
Winters long & cold
Evergreen coniferous trees with needle-like leaves
Plant & animal diversity low
Tundra Very cold/ Brief summerTreeless< 10” Precip. / Permafrost Short
PlantsTaiga
Deciduous Forest
Grassland
Desert
Tropical Rain Forest
Conifers(Spruce/Fir)
Long winter/Short SummerLow Precip.
BiomeBiome ClimateClimate Dominant Dominant PlantsPlants
3.3. Temperate Deciduous Temperate Deciduous ForestsForests
Temperate Deciduous Temperate Deciduous ForestForest30-60 in. rain
annually, most during summer
Mostly deciduous trees, bare in winter
Leaf litter on soil
High diversity of animals
Tundra Very cold/ Brief summer Treeless< 10” Precip. / Permafrost Short Plants
Taiga Long winter/Short SummerConifersLow Precip. (Spruce/Fir)
Deciduous Forest
Grassland
Desert
Tropical Rain Forest
Deciduous Trees(Oak, Maple, Elm)
Cold winter/Warm summer30 - 60” Precip.
BiomeBiome ClimateClimate Dominant Dominant PlantsPlants
Temperate Rain Temperate Rain ForestForest
Temperate Rain ForestTemperate Rain ForestAbundant rain
Soil seldom freezes
Usually coastal
4.4. GrasslandsGrasslands
GrasslandGrasslandss10-30 in. rain/year
Usually in centers of continents
No trees except by rivers
Periodic droughts
Frequent fires
Most fertile soil in world
Overgrazing problems
Shortgrass PrairieShortgrass Prairie
Sagebrush Desert orShortgrass Prairie
Sagebrush Desert orShortgrass Prairie
Tundra Very cold/ Brief summer Treeless< 10” Precip. / Permafrost Short Plants
Taiga Long winter/Short summer ConifersLow Precip. (Spruce/Fir)
DeciduousCold winter/Warm summer Deciduous
Trees Forest 30 - 60” Precip. (Oak, Maple, Elm)
Grassland
Desert
Tropical Rain Forest
Grasses, GrainsTall wildflowers
Cold Winter/Warm Summer10 - 30” Precip.
BiomeBiome ClimateClimate Dominant Dominant PlantsPlants
5.5. DesertsDeserts
DesertDesertUsually found between 20-30° N & S latitude
Less than 10 in. rain/yr.
Boom & bust population growth after rain
Very fragile ecology
Tundra Very cold/ Brief summer Treeless< 10” Precip. / Permafrost Short Plants
Taiga Long winter/Short summer ConifersLow Precip. (Spruce/Fir)
Deciduous Cold winter/Warm summer Deciduous Trees Forest 30 - 60” Precip. (Oak, Maple, Elm)
Grassland Cold Winter/Warm Summer Grasses, Grains10 - 30” Precip. Tall wildflowers
Desert
Tropical Rain Forest
Sparse Veget.(Cactus, etc.)
BiomeBiome ClimateClimate Dominant Dominant PlantsPlants
Cold Winter/Hot summer< 10” Precip.
Sonoran DesertSonoran DesertArizona
Flowers indicate recent rain
Saguaro cactus unique to this desert
Environment Molds Physical Environment Molds Physical TraitsTraits
An AmericanAn Americancactuscactus
An AfricanAn Africaneuphorbeuphorb
ChaparralChaparral
The Chaparral BiomeThe Chaparral BiomeOften in coastal regions bordering deserts
Up to 30 in. rain annually, but all during cool months
Summers hot & dry
Small trees & large bushes
6.6. Tropical Rain Tropical Rain ForestForest
Tropical Rain Forest Tropical Rain Forest BiomeBiomeTemp 77-86 °F
Rainfall 100-160 inBiodiversity: 50-67% of all Earth’s species6% of land area40% now gone- Losing 70 acres/min> 25000 species go
extinct annuallyDominated by large, broadleaf, evergreen, complex forests
Complex, Evergreen, Broadleaf Forests
Tundra Very cold/ Brief summer Treeless< 10” Precip. / Permafrost Short Plants
Taiga Long winter/Short summer ConifersLow Precip. (Spruce/Fir)
Deciduous Cold winter/Warm summer Deciduous Trees Forest 30 - 60” Precip. (Oak, Maple, Elm)
Grassland Cold Winter/Warm Summer Grasses, Grains10 - 30” Precip. Tall wildflowers
Desert Cold Winter/Hot summer Sparse Veget.< 10” Precip. Cactus, etc.
Tropical Rain Forest
No winter
BiomeBiome ClimateClimate Dominant Dominant PlantsPlants
Tropical Deciduous Tropical Deciduous ForestForest
SavannaSavanna
The African SavannaThe African SavannaGrasses dominate; scattered trees Short rainy season
<12 in. (30 cm)/year
Long, severe droughts
African savanna with many large animals
Many species in danger of extinction
Ecosystem Productivity Ecosystem Productivity ComparedCompared(Grams of biomass/meter(Grams of biomass/meter22/year)/year)
OpenOpenOceanOcean(125)(125)
NeriticNeritic(360)(360)EstuaryEstuary
(1500)(1500)
TropicalTropicalRainforestRainforest
(2200)(2200)
TundraTundra(140)(140)
TaigaTaiga(800)(800)
TemperateTemperateDeciduous ForestDeciduous Forest
(1200)(1200)
GrasslandGrassland(600)(600)
DesertDesert(90)(90)
The The
EndEnd