chapter 3 communities and biomes part 1 ecosystem: interactions among populations in a community...
TRANSCRIPT
Chapter 3Communities and Biomes
Part 1
Ecosystem: interactions among populations in a community
• Consists of:– A community of organisms– The soil, water, and weather– Energy
Biome - a major ecosystem that shares the same type of climate and has similar life forms.
1. Salt water
2. Freshwater
3. Estuary
4. Terrestrial
CLIMATOGRAM - Measures two things:
• Average Temperature • Average Precipitation
TundraPermafrost - permanently frozen groundPlants - short roots; fast growing; perennials. Animals have thick fur / body fat / coloration.
Taiga / Coniferous ForestConifers - cone-bearing trees / bending branches / needles
as leaves. Animals also have thick fur / body fat.
DesertMost desert animals are nocturnal.
Estivation - sleeping during hot days.Plants have waxy leaves / spines.
GrasslandsMost animals have good vision and speed.
Plants have underground stems / survive fires.
Temperate / Deciduous ForestBroad-leaved trees lose their leaves yearly.
Some birds migrate.
Tropical Rain ForestArboreal - tree-dwelling animals
Trees / Plants:1. Canopy 2. Understory 3. Ground
Adaptation: the process by which a species becomes better suited to its environment.
• Migration• Thick fur• Coloration• Speed• Chemical defenses• Hibernation/ Estivation• Size• Thorns and stickers
Chapters 3-4Communities and Biomes /
Population
Part 2
Click to start video
Succession: changes over time• Primary succession – new land caused by
avalanches, volcanoes, and glaciers
Succession: changes over time• Pioneer species – first species in an area
Succession: changes over time• Climax community – shows little or no change over time• Secondary succession – sequence of life after natural
disasters (ex. Forest fires)
1988 forest fire inYellowstone Nat’l Park
Population Dynamics• Exponential Growth - as a population gets
larger, it also grows faster. (p 97)• Carrying capacity - the maximum number
of organisms that an environment can support (p 98).
Limiting factors: Factors that affect an organism’s ability to survive.
• Density dependent factors:– Disease – Competition – Parasites – Food & water – Space
Density independent factors (abiotic factors):
– Temperature – Storms – Floods – Drought– Habitat disruption (logging,
burning, draining swamps, moving in exotic species)
Demography - human population growth
• Immigration - moving in• Emigration - moving out• Growth rate• Natality - birth rate
• Fatality - death rate