Ecology - PowerPoint Presentation

Slide1

Ecology

We may have heard the word “ecology” before without really understanding what it means. So a good place to begin might be to begin with a good definition. It was a German biologist, Ernst Haeckel, who first coined the word in 1866. One way to define ecology is“the study of the interaction of living things with each other,and with the non-living parts of their environment.”Slide2

Ecology

The word “ecology” comes from the Greek words oikos meaning “the place where one lives,” and logos which means“study of.”Slide3

Organism

Animal and plants are examples of living things in our environment. If we focus on just one example of a living thing, we can use the wordorganism to representthat single life form.For example a frog is an organism.Slide4

Biotic Factors

In ecology living things that affect other living things are called biotic factors.For example, biotic factorsthat might influencethe life of this frog could be the plant lifearound it, or possibly

a

nimals such as snakes

that might eat it.Slide5

Abiotic Factors

There are also parts of our environment that are not living. In ecology the non-living things that affect living things are called abiotic factors.For example, abiotic factors that might influence the life of thisfrog could be the amountof sunlight, t

he air

temperature, and how

strong the wind is.Slide6

Population

Living things usually do not live by themselves. Living things often live together with other members of their own species. The term population refers to all members of the same species that live in the same ecosystem or habitat.Slide7

Population of Frogs

In our example, all the frogs in a habitat would be referred to as a population of frogs. The photo below shows a population of 4 frogs.Slide8

The Thin Green Linehttps://www.youtube.com/watch?v=nBbkwlGM7X0Slide9

More Than Just Frogs

Any place that an ecologist is studying usually has more than one species living in it. So for example a pond may have more than just frogs. It may also have mosquito larvae, tadpoles, minnows, algae, and plants and animals of various kinds.Slide10

Community

There is a name given to all the populations of species in an ecosystem.We call this a community. All those plants and animals that live with the frog are part of the community in the pond.Slide11

Studying a Community

When a scientist studies a community, he might want to learn about how biotic factors affect the community. For example, in studying a pond community, the scientist may want to know how plants and animals in the community affect each other.Slide12

Ecosystem

Now suppose that the scientists wants to study more than the populations in a community. He may also want to study how physical systems such as sunlight and rain affect the populations. Now we can say that he is studying an ecosystem.Slide13

Ecosystem

Here is more of a text book definition of an ecosystem. An ecosystem is a specific place defined by an ecologist where there is an interaction between populations of species. It is also the interaction between thosepopulations and the non-living (abiotic) factorsin the environment.Slide14

Ecotone

There is not a sharp boundary from one ecosystem to the next. For example, the diagram shows a pond ecosystem to the left and a field ecosystem on the right. But there is a region between them that hassome characteristics of both. The transitionarea between two ecosystems is called an ecotone.Slide15

Transition Areas

The ecotone in this example may have frogs or mosquitos that are also found mainly in the pond area. It may also have racoons and butterflies that are found mainly in the field ecosystem.These ecotone areasare rich in differentspecies. We can say

t

hat they have a

h

igh degree of

b

iodiversity

.Slide16

Diversity in the Ecotone

The ecotone in this example may have frogs or mosquitos that are also found mainly in the pond area. It may also have racoons and butterflies that are found mainly in the field ecosystem.Slide17

Biosphere

Now let’s take a muchlarger view. The biosphere is a thin layer of air, land, andwater on or near Earth’s surface in which all living things on Earth exist. It is a global sum of all ecosystems. If an apple represented Earth, the biosphere would be the thickness of the apple’s peal. The diagram at the right shows how the term “biosphere” is related to other terms in ecology.Slide18

Biome

The biosphere representsall of Earth and an ecosystem is one small part of the biosphere. Ecologists also study larger parts of the biosphere called biomes. A biome is a large region within a biosphere that has similar biotic and abiotic components. For example, much of Manitoba is covered by the Boreal Forest biome.Slide19

Western Hemisphere Biomes

The diagram atthe right showsthe major biomesin the WesternHemisphere.Slide20

Habitat

Now we turn from a large area to a small one. A habitatis the place in which anorganism lives. For example,a red-backed salamander makes its nest in the decaying wood of a fallen tree. For a frog, it could be a pond. The diagram shows how a habitat, and ecosystem, and a biome are related to each other.Slide21

Checklist

1. Define the following terms: ecology, organism, biotic factors, abiotic factors, population, community, ecosystem, ecotone, biodiversity, biosphere, biome, habitat2. List examples of biotic and abiotic factors in an environment.Slide22

Practice

The following are partial definitions of important terms in ecology. For each one, complete the sentence.a) Ecology is defined as the study of the interaction of living things with each other, and with the non-living parts

of

their

environment

.

b)

Biotic

factors are

living

things

that affect other

living

things

.

c) An

organism

is a single

life form

.

d)

Abiotic factors

are the

non-living

parts of our environment that affect living things.

e) A

population

refers to all members of the

same species

that live in the same ecosystem or habitat.

f) A

community

is made up of

all

the

populations

of

species

in an

ecosystem

.Slide23

Practice

g) An ecosystem is a specific place defined by an ecologist where there is an interaction between populations of species. It is also the interaction between those populations

and the

non-living (abiotic)

factors in

the environment

.

h) An

ecotone

is the

transition

area

between two

e

cosystems

.

i

) A high degree of

biodiversity

refers to the richness of different

species

in an area, especially in an

ecotone

.

j) The

biosphere

is a thin

layer

of

air

,

land

,

and

water

on or near

Earth’s

surface in which all

living things

on Earth exist.

k) A

biome

is a large region within a

biosphere

that has similar

biotic and

abiotic

components

.

l) A

habitat

is

the

place

in which

an

organism

lives.Slide24

Practice

2. In defining ecology, we make use of two root Greek words. What are these two root words and what do they mean?The word “ecology” comes from the Greek words oikos meaning “the place where one lives,” and logos which means “study of.”Slide25

Practice

3. Jimmy has a backyard vegetable garden. He is learning about how plants grow and about where his food comes from. For this garden, what would an example of a “population” and how would it be different from a “community?”The word “population” could be applied to all the vegetables of one kind, for example, all the carrots in the garden. The word “community” would be applied to all the living things in the garden such as all the other vegetables and plants (possibly weeds), any animals that may live there (insects such as butterflies, earthworms, and so on).Slide26

Practice

4. This is a photograph of Assiniboine Forest in Winnipeg. You can see some trees. What are two examples of biotic factors and two examples of abiotic factors that can affect the lives of trees in this area?There are many possible answers here.Two examples of biotic (living) factors could be other plants around the trees competing for soil nutrients,

or animals such as deer that may use

part of the tree for food.

Two examples of abiotic (non-living) factors could be the amount of sunlight or rain that the trees receive.Slide27

Practice

5. Where would you likely Find more species, a forest,an open field, or the forest-grassland ecotone between them?You would most likely find the greatest diversity in the forest-grassland ecotone. There will be some species from both ecosystems in this transition area between the two ecosystems. Slide28

Practice

6. The diagram at the right shows the changes in population growth of one-celled organisms called paramecia.Look at the number of paramecia in Beaker A And Beaker B towards the end of the

recorded time. Now look at Beaker C.

What evidence is there that shows that

the populations of

paramecia

affect

each other?

For both populations 1 and 2, there are

fewer numbers of paramecia than was the

case when they lived in separate containers.

This is especially the case for Species 2 whose

numbers have gone down by a large amount.Slide29

Practice

7. Abiotic factors can determine what life exists in an ecosystem. Go to the following site:https://www.youtube.com/watch?v=7Wfs2L5IydYThe video shows examples of how the abiotic factor water determines life in ecosystems. Give at least two examples shown in the video.A lack of water in the desert means that camels and cacti live there. A great deal of water would be required for a hippopotamus. Also ocean fish require salt water while river fish live in fresh water.