slide1 n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Populations in Ecology PowerPoint Presentation
Download Presentation
Populations in Ecology

Loading in 2 Seconds...

play fullscreen
1 / 16

Populations in Ecology - PowerPoint PPT Presentation


  • 120 Views
  • Uploaded on

Lesson # 27. Populations in Ecology. ECOLOGY. It is the study of the interaction that living things have with each other and with their environment. Importance of Ecology. It provides the information base that society can use to make decisions about the environment . E C O L O G Y .

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Populations in Ecology' - dino


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
slide1

Lesson # 27

Populations in Ecology

slide2

ECOLOGY

It is the study of the interaction that living things have with each other and with their environment

Importance of Ecology

It provides the information base that society can use to make decisions about the environment

slide4

For Ecology, life is organized into:

1- Population

All the members of a single species that live together in a specific geographic region.

2- Community

The population of all species living in a single region.

3- Ecosystem

It is the community plus all the non-living elements that interact with it (rainfall, chemicals nutrients, soil).

4- The Biosphere

It is the interactive collections of all the Earth’s ecosystems.

slide6

25,000

22,000

19,000

16,000

13,000

10,000

7,000

4,000

1,000

1

4

7

10

13

16

19

22

25

Populations: Size and Dynamics

Arithmetic growth

slide7

256,000

128,000

Water flea Daphnia

64,000

32,000

16,000

8,000

1

4

7

10

13

16

19

22

25

Exponential growth

slide8

Populations growth exponentially because each living thing is capable of playing part in giving rise to more units.

slide9

Environmental Resistance

CharlesDarwin: “There is not exception to the rule that every organic being naturally increase at so high a rate, that, if not destroyed, the Earth would soon be covered by the progeny of a single pair”.

Logistic growth: Population starts growing exponentially, but eventually the rate of growth slows and finally ceases altogether, stabilizing at a certain level (K).

slide10

Factors that limit population growth

Environmental Resistance

1- Water supply

2- Food supply

All the forces of the environment that act to limit population growth.

3- Living space

4- Diseases

5- Predators

6- Wastes produced by the organisms

slide11

Environmental Resistance

Carrying capacity (K)

It is the maximum population density of a given species that a defined geographical area can sustain over time.

slide12

When species stabilize their rate of growth to a certain level they are known as “equilibrium species”

The growth of the population of equilibrium species is limited by carrying capacity (K)

slide13

Favorable weather

Fly population increases enormously

Abundant food supply

Change in temperature

Fly population decreases enormously

Food is gone

In contrast to equilibrium species, other species like houseflies tends to fluctuate greatly in reactions to variations in its environment

When population size tends to fluctuate greatly in reactions to variations in its environment they are known as “opportunistic species”

slide14

The population sizes of these species tend to be only limited by their reproductive rate ( r ).

r-selected species: Species whose population sizes tend to be limited by reproductive rate.

slide16

POPULATION SIZE

Limited by carrying capacity (K)

Limited by reproductive rate ( r )

Density dependent

Density independent

Relatively stable

Relatively unstable

ORGANISMS

Larger, long-lived

Smaller, short-lived

Produce fewer offspring

Produce many offspring

Provide greater care for offspring

Provide no care for offspring