PowerPoint Template

Download Report

Transcript PowerPoint Template

Chapter 4
Population Biology
Section 4.1 Population Dynamics
Section 4.2 Human Population
Section 4.1 Population Dynamics
Compare
&
contrast
Relate
Predict
exponential and linear
population growth.
the reproductive patterns of
different populations of
organisms to models of
population growth.
effects of environmental
factors on population growth
Principles of Population Growth
J-shape growth
as a
population
gets larger, it
also grows at
a faster rate
Principles of Population Growth
Carrying capacity (负载能力)
The number of organisms of one
species that an environment can
support indefinitely is its carrying
capacity
When a population overshoots the
carrying capacity, then limiting
factors may come into effect
Principles of Population Growth
S-shape growth
as a
population
gets larger, it
also grows at
a faster rate
Reproduction Patterns
life-history pattern
Rapid life-history
organisms have a
small body size,
mature rapidly,
reproduce early,
and have a short life
span
Slow life-history
organisms reproduce
and mature slowly, and
are long-lived. They
maintain population
sizes at or near
carrying capacity.
Reproduction Patterns
Density-dependent factors
Include disease, competition, predators,
parasites, and food.
These factors have an increasing
effect as the population increases.
Reproduction Patterns
Density-independent factors
such as volcanic eruptions, temperature,
storms, floods, drought, chemical
pesticides, and major habitat disruption
Reproduction Patterns
Density factors and
population growth
1
2
3
ThemeGallery is a
Design Digital
Content & Contents
mall developed by
Guild Design Inc.
ThemeGallery is a
Design Digital
Content & Contents
mall developed by
Guild Design Inc.
ThemeGallery is a
Design Digital
Content & Contents
mall developed by
Guild Design Inc.
Organism InteractionsLimit Population Size
Predation affects population size
Organism InteractionsLimit Population Size
Competition within a population
The effects of crowding
and stress
Section 4.2 Human Population
Identify
Compare
Explain
how the birthrate and death
rate affect the rate at which a
population changes
the age structure of rapidly
growing, slow-growing, and nogrowth countries
the relationship between a
population and the environment
World Population
World Population
Calculating growth rate
Population Growth Rate (PGR)
=(Birthrate +Immigration rate)(Death rate +Emigration rate)
Or = Birthrate rate- Death rate
World Population
Doubling time
the time needed for a population to
double in size
World Population
Age structure
refers to the proportions of the population
that are in different age levels