Environmental ScienceChapter 8 Lecture Notes

Understanding Populations

Chapter 8 Targets1. Explain the difference between a population

and a community.

2. Explain the difference between population density and population dispersion.

3. Calculate population rates using birth and death rates.

4. Explain the difference between reproductive potential and biotic potential.

What is the difference between a population and a community?

T1

Properties of Populations

• Density

• Dispersion

T2

COMPREHENSION CHECK

• Calculate the population density of each population below. Each square represents 1 square meter.

• Which is more crowded?

How Does a Population Grow? T3

How Does a Population Grow?

T3

Reproductive Potential T4

BIOTIC POTENTIAL T4

Comprehension Check• A population of mice has a total of

200 births and 50 deaths over a 5 week time period. What is the growth rate of this population?

Chapter 8 Targets

5/6. I can draw a graph that would represent exponential growth and calculate geometric growth.

7/8. I can draw a graph that would represent arithmetic growth and calculate arithmetic growth.

10. I can define the Law of Limiting Factors.

11/12. I can name abitoic and biotic limiting factors.

Exponential Growth T 5/6

How are the growth patterns different for each line below?

Population

Years

T 5/6

T 7/8

Comprehension Check• Does the following

table represent arithmetic or geometric growth? How can you tell?

• How would geometric growth look?

Week # Bats

1 4

2 8

3 12

4 16

5 20

LAW OF LIMITING FACTORS

T 10

ABIOTIC LIMITING FACTORS

T 11

BIOTIC LIMITING FACTORS

T 12/13

Intraspecific Competition

Interspecific Competition

T 12/13

Biotic Limiting FactorsT 12/14/15

Two Types of Population Regulation

• Density-Dependent Limiting Factors

• Density-Independent Limiting Factors

T 17

Carrying Capacity T 19

GROWTH CURVES T 18/19

S-Shaped Growth Curve T 19