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Y12APPLIEDSCIENCE

ECOLOGY

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INDEX

ECOLOGY.....................................................................................................................4ADAPTATIONS............................................................................................................6

1. STRUCTURAL ADAPTATIONS.................................................................62. BEHAVIOURAL ADAPTATIONS..............................................................63. PHYSIOLOGICAL ADAPTATIONS...........................................................6

COMPETITION.......................................................................................................12HABITAT................................................................................................................12

ENERGY......................................................................................................................15TROPHIC LEVELS.................................................................................................15FEEDING RELATIONSHIPS.................................................................................18

SYMBIOSIS........................................................................................................18COMMENSALISM.............................................................................................18PARASITISM......................................................................................................18PREDATION.......................................................................................................20

PATTERNS IN A COMMUNITY..........................................................................211. ZONATION.................................................................................................212. STRATIFICATION.....................................................................................223. SUCCESSION.............................................................................................23

POPULATIONS......................................................................................................24FIELD WORK.............................................................................................................25US21610 – COLLECT, AND USE COMPUTER TECHNOLOGY TO STORE AND PROCESS, NUMERIC DATA FOR A SCIENTIFIC PURPOSE..............................40GLOSSARY………………………………………………………………………….41

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Understand the terms ecology, environment, habitat, niche and ecosystemBe able to explain that an adaptation is a feature that an organism has that enables it to survive in its environmentUnderstand trophic levels and state why each is importantDefine community, population, abiotic and bioticBe able to define and give examples of feeding relationshipsConstruct food chains and a food web and understand energy flow through a communityCompare habitats of organisms in your areaInvestigate patters within a community such as succession, stratification, zonation and diversity.Understand why certain species dominate an areaKnow how to use a transect and quadrats to collect data.Conduct a field study looking at diversity patterns and write a report.

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ECOLOGYEcology is the study of organisms in their home.

We need to understand how organisms interact with other organisms, their surroundings, the weather, pollution etc.

In this unit of work we are going to study ecosystems.

An ecosystem is a study of biological communities of plants and animals and how they interact with their physical environment.

The Ecosystem consists of all the living and non-living things in a specified area that influence each other.

The Community consists of all the living species in one area.

The Population consists of one species in the community, that are able to interbreed.

So although we are studying the biological communities within an area, we really need to look at the ecosystem as a whole, because other things affect where species live and why.

We are going to be looking at a number of ecosystems and studying why certain species live in certain areas. To do this we need to look at their adaptations, their feeding relationships and their environment.

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HOW IT ALL FITS

Environment

Biosphere Atmosphere Lithosphere Hydrosphere

Earth’s structure

Tectonic Plates

RockCycle

Oceans

Seas

Lakes

Rivers

Climate

Structure ofatmosphere

Weather

Biomes

Zones

Habitats

ECOSYSTEM

COMMUNITY

Population

Organism

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ADAPTATIONS

Living things do not live all by themselves, with food provided and a warm bed to curl up in at night all free of charge. All living things have to fight for their right to survive. Many species have adapted to their environment in a specific way, which allows them to have an advantage over would be competitors.

1. STRUCTURAL ADAPTATIONSThese are adaptations that the organism has made to its structure to help it survive.ExampleSpines on gorse bushes prevent it being eaten.The large fleshy water logged cactus trunks enable it to survive very arid conditions.

2. BEHAVIOURAL ADAPTATIONSThese are adaptations that an organism has made in its behaviour to help it survive.ExampleRabbits only come out at night as there is less chance of being seen and eaten.Deer run away hearing an unexpected noise, to avoid being caught by predators.Sunflowers follow the sun to gain maximum sunlight for photosynthesis

3. PHYSIOLOGICAL ADAPTATIONSThese are adaptations that an organism has made in the workings of its body to help it survive.ExampleFlowers produce nectar to attract insects for pollination.Humans produce enzymes to help absorb food more quickly.

Species that have similar adaptations will be suited to similar habitats. This leads to competition between species. Unless the species have slightly different niches (jobs).

On the next page are some pictures of animals in their natural habitats. Use books or the internet to:

State what adaptations these animals have to help them survive in their environments.

Determine whether these adaptations are structural, behavioural or physiological.

State the niche that the animal occupies.

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NZ’s Blue Heron Kiwi

PekaPeka (Short Tailed bat)

Pingao (NZ Dune Grass)

KakapoTuatara

This page for your findings.

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Here are two animals that occupy the same bush habitat. How do they avoid competing with each other for food, shelter etc?

And

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Your teacher will now take you to look at two species. You are to identify the adaptations, habitat and niche of each. You are also to try and imagine what else could affect the life of your species. You will report back to your class, with a power point or poster presentation, showing the similarities and differences between your two species.

Species 1

Type of AdaptationFunction the Organism must be able to carry out

Structural Behavioural Physiological

Obtain food

Exchange gases

Move

Sense Surroundings

Excrete Wastes

Reproduce

Protect itself from predators and the environment

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Species 2

Type of AdaptationFunction the Organism must be able to carry out

Structural Behavioural Physiological

Obtain food

Exchange gases

Move

Sense Surroundings

Excrete Wastes

Reproduce

Protect itself from predators and the environment

Similarities

Differences

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COMPETITION

Plants and animals will die, if they are not well adapted to their environment. How could a fish possibly survive on land? It is however, well adapted to its watery environment.

Animals and plants compete with each other for resources such as food, light, water and space. The organism that is best adapted for the environment will be the one that survives.

Competition occurs when two or more organisms are trying to obtain something that is in short supply. As a result of competition an organism may reproduce / grow much more slowly or even die.

Plants may compete for Animals may compete for Light Water Minerals Nutrients Carbon dioxide Pollinators Germination sites

Food Space Nesting sites Territories Mates Water

HABITAT

By analogy,

it may be said that the habitat is the organism's "address", and the niche is its "profession", biologically speaking.

EXAMPLE

Oak trees live in oak woodlands; that's common sense. The oak woodland is the habitat. So if you were writing a letter to an oak tree you would address the letter to:

Sir Deciduous Oak Tree,The Oak Forest,England,U.K.

What do oak trees do? If you can answer that question you know the oak trees "profession" or its ecological niche. Perhaps you think that oak trees just stand there looking pretty and not doing vey much, but think about it.

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Oak trees:

1. absorb sunlight by photosynthesis; 2. absorb water and mineral salts from the soil;

3. provide shelter for many animals and other plants;

4. act as a support for creeping plants;

5. serve as a source of food for animals;

6. cover the ground with their dead leaves in the autumn.

These six things are the "profession" or ecological niche of the oak tree; you can think of it as being a kind of job description. If the oak trees were cut down or destroyed by fire or storms they would no longer be doing their job and this would have a disastrous effect on all the other organisms living in the same habitat.

The habitat of an organism is affected by various conditions, which can make the habitat suitable for one organism, but not another.

Factors which affect a habitat can be divided into BIOTIC AND ABIOTIC factors. Biotic means biological factors and Abiotic means non-biological facors, or physical factors.

Biotic Factors Abiotic Factors Predators Parasites Food supply Human interference Competition

Light Intensity Temperature Humidity Oxygen and Carbon Dioxide

levels Exposure Wave action Soil/water pH Rainfall Wind Soil type Salinity

Organisms in different habitats are affected by different factors.

Example: Some of the environmental factors that could affect a fish are:

Food supplyWave action

Parasites

Dissolved gases

Salinity

Pollution pH

Competition Temperature

Predators

Human activities

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Now look at the picture below and fill in some of the environmental factors that could affect these organisms.

Environmental Factors: that could affect this cute bunny are…..

Environmental Factors: That could affect this pretty flower are……..

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ENERGY

The sun supplies energy to all life on Earth. However, animals have no means of harnessing this energy for their bodies. Plants on the other hand carry out photosynthesis and can convert the sun’s energy into carbohydrates, which they store in their leaves, fruits and tubers. Animals can then access this energy by eating plants.

Thus as plants are the only organisms able to manufacture food from the sun’s energy they are called PRODUCERS all other organisms are CONSUMERS. Consumers can not manufacture their own food and need to eat for energy. The position of an organism on a food chain is called its trophic level. Energy from the sun is passed along in a food chain. Most commonly numerous food chains are linked together in a food web.

There is a limit to the number of trophic levels in a food chain/web. This is because only about 10% of the energy consumed is passed along. Most of the energy that is consumed is used for life processes, in particular heating. Thus as you move up through a food chain/web there are less organisms able to be supported.

TROPHIC LEVELS

Each step or trophic level (trophic = feeding) in a food chain is given a name. Producer, herbivore, carnivore and decomposer are common names, but there are other names that can be used for each position in a food chain.

An organism may belong to more than one feeding level, depending on what particular food chain (within a complex food web) that you are looking at.

Plant Plankton

AnimalPlankton

Shrimps

Rock Oysters

Mussels

Mullet(small fish)

Oyster Borer

Starfish

Kahawai(large fish)

Dark RockShell

humans

Seagull

1st Trophic Level

Producer

Producer

2nd Trophic Level

1o Consumer

Herbivore

3rd Trophic Level

2o Consumer

1o Carnivore

4th Trophic Level

3o Consumer

2o Carnivore

5th Trophic Level

4o Consumer

3o Carnivore

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In food webs and chains the arrow points in the direction of energy flow.

QUESTIONS1. Who eats the Daphnia?

2. Who is eaten by the frog?

3. List the producers

4. Draw two food chains of at least 3 trophic levels.

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FEEDING RELATIONSHIPS

In a community there are many relationships, both between members of the sam species (intraspecific relationships) and between members of different species (interspecific relationships). Many relationships result in both organisms benefiting. They may gain mates, space, shelter or food. Other relationships such as parasitism result only in one organism benefiting whilst the other may be harmed or unaffected.

FeedingRelationship

OrganismA

OrganismB

Example

Symbiosis(Mutualism)

Beneficial Beneficial Root nodules on legume plants

Commensalism Beneficial Not Affected Sucker fish on a shark

Parasitism Beneficial Harmful Flea on a dog

Predation Beneficial Harmful Cat with a mouse

SYMBIOSIS

Often called MUTUALISM. Quite often in this kind of relationship it will be found that neither organism can live without the other. A common example is the nitrogen fixing bacteria that live in the root nodules of legumes. The plant gets a source of nitrogen, whilst the bacteria get a place to live and also obtain sugars from the plant.

Another example is the cow and the bacteria that live in their stomachs. The bacteria break down the cellulose in the plant cell walls so that the energy can be released. The cow gets to use the energy and again the bacteria have food and a place to live.

COMMENSALISMThis is a term used to describe the type of relationship where only one of the two organisms gains any benefit, yet no harm comes to the second.

e.g Sharksuckers and sharks. The sharksucker benefits by saving energy from limiting its swimming and obtaining food scraps when its host is feeding.

PARASITISMThese are organisms that are especially adapted to live on or in a host. They live off their host and usually cause it harm. There are two types.

1. Endoparasites - live inside their host e.g tapeworm in dogs.

2. Ectoparasites – live on the outside of the host. E.g. fleas on a cat.

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SOME PARASITE EXAMPLES

TAPEWORM – an endoparasite

The tapeworm is a flatworm whose main host is the dog. It lives in the dog’s intestine and causes fluid filled cysts containing tapeworm eggs to form around major organs. It can also be contracted by humans from eggs in a dog’s fur and causes mild to serious abdominal pain, in serious cases can result in a need for liver transplants.

ADAPTATIONS1. No digestive system – just a thin body to absorb the food that has already been

digested by the host.2. No eyes as it has no need for them.3. A double row of hooks and four suckers to hold on through all sorts of

intestinal motions.4. A mucus covering to protect against the host animal’s digestive juices.5. A large number of eggs are produced because a lot are lost in the transfer

between hosts.

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THE FLEA – an ectoparasite

This parasite survives by sucking blood from birds and mammals.

ADAPTATIONS

1. Flat sides to make movement between feathers and hairs easy.

2. Large hind legs to make jumping from host to host eash.

3. No wings – these could get caught in hair or feathers.

4. Piercing mouthparts to break the skin.

5. Salivary glands that secrete a juice to prevent blood clotting.

6. A tough exoskeleton

7. Claws at the end of each leg to prevent dislodgement.

PREDATION

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PATTERNS IN A COMMUNITYIn your community you should have noticed patterns. Two of these can be seen easily and one not so easily.

1. ZONATION

This is the distribution pattern that occurs along the ground due to different biotic and abiotic conditions. Examples can be seen on sand dunes or at a beach, where different organisms occupy the zones of low tide, mid tide and high tide.

The organisms are suited / adapted to their particular habitat and thus show definite zones of preference. They usually cannot tolerate the variety of habitats in the area and thus do not show a range of distribuitions.

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2. STRATIFICATION

This is a distribution pattern on a vertical scale rather than along the ground.

In the top canopy there are a

number of trees that have made it up to where the sun is. Plants living below this level have special adaptations to enable them to survive in the area such as large leaves to increase the surface area for sunlight absorption.

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3. SUCCESSION

This is a pattern that can really only be seen over time. Good examples are where an area has been burned or cleared. The first plants to appear may be grasses or clover. They can grow easily on poor soil and create a micro-climate. As they fertilise the soil the second generation of plants can then develop. These may be bracken and gorse, both of which provide shelter for the slower growing native plants.

Eventually a state is reached where the community does not change from year to year. It is then a stable or climax community. What plants are in the climax community is largely determined by the climate and soil of the area.

POPULATIONS

If a few individuals enter an unoccupied area, and assuming that there are plenty of resources, they will begin to reproduce.

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The population will grow exponentially and this represents the maximum growth rate of a population.

The absence of predators and competition means that there is no environmental resistance to population growth. If the growth of the population was to continue at an exponential rate, eventually there would be overcrowding, and lack of resources.

This is prevented from happening by environmental resistance. The environment becomes saturated with this particular species reaching its full carrying capacity. When this point is reached the birth and death rates exactly balance each other.

Environmental resistance possibilities are:

1. Shortage of food, water or oxygen2. Lack of light3. Predators4. Lack of shelter5. Disease6. Toxic waste accumulation

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FIELD WORK

You are required to conduct a study of a steam in the Piha region.

To be a good fieldworker you need to. Be aware of your surroundings Take plenty of accurate data Be very observant

You also need to take care not to upset the natural balance of the area. When you are out in the field the point of the exercise is to see the populations, relationships and patterns the way they are naturally.

You are to be studying two communities that show a pattern due to abiotic and biotic influences. You will be studying two different stream communities.

Communities are composed of a number of populations in a defined area. For example you could study a rosebush community, or look at a back yard community.

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In your first practice study you are going to look at a rosebush community.

1. What other varieties of plants are close by your rose bush?

2. Roughly sketch the area around your rose bush, (up to about 10m in diameter)

3. Is the bush in full sun, partial sun or full shade?

4. Are there any factors that may shade the bush from wind, rain etc?

5. Is the plant cared for? Has it been pruned? Has it been sprayed lately?

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6. If your rose bush is really big, chose one branch. Before starting your ‘count’, observe the bush for visiting insects and count and identify them. Count and identify all the organisms that you find on the bush and around the base.

Type of Bug No of Bugs % of Total Number of Bugs

Monarch Butterfly

Earwig

Thrush

Praying mantis

Scale insect

Robin

Caterpillar

Spider

Lacewing

Aphid

Mosquito

Ladybird

Ant

Snail

Slater

Earthworm

Fly

Bee

% of Ants = Number of Ants x 100Total number of bugs

Now draw a bar graph of your findings.

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Now write a couple of paragraphs describing the community on your bush and how it may have been affected by biotic and abiotic factors. Include in your discussion an explanation of how the different species are adapted to their habitats.

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A STUDY TO COMPARE TWO SEASHORE COMMUNITIES

In this investigation you are to collect information from a seashore community and compare it to information about a different seashore community.

Task 1 and 2 need to be completed in the field whilst tasks 3 and 4 need to be carried out individually in the classroom.

TASK 1 – EXAMINING THE COASTAL ENVIRONMENT

PART A: SKETCH MAP FOR COMMUNITY 1 - ROCKY

On your sketch indicate An approx scale The sample site Vegetation around the site Large boulders Areas of slow and fast moving water Any plants

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PART B: COASTAL SURVEY FOR COMMUNITY 1 - ROCKYEastern End Cornwallis

What plants are present, close to, the shore?Trees = mainly PohutakawaGrass

Name the dominant plant for the following

Trees/shrubs ______Pohutakawa_____________

Ground cover________Grass_______________

Do the plants help prevent erosion of the shoreline?Yes the grass holds the shoreline in place. And the pohutakawas help in this.

Is the shore in shade at all during the day?The beach is, from the trees.The shore is only in late afternoon after 4pm, due to the cliffs a bit further along.

What is the bottom of the seabed like? Rock

What is the land immediately before the shoreline used for? Recreational activites and some fishing from the rocks

Has the foreshore been altered by humans at all?

Vegetation cleared for the grass and pohutakawas.Some rubbish from human accessRoad about 100m away.Lots of fishing being carried out.

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PART A: SKETCH MAP FOR COMMUNITY 2 - OPEN

On your sketch indicate An approx scale The sample site Vegetation around the site Large boulders Areas of slow and fast moving water Any plants

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PART B: COASTAL SURVEY FOR COMMUNITY 2 - OpenCentral City

What plants are present, close to, the shore?

Name the dominant plant for the following

Trees/shrubs ______ _____________

Ground cover________ _______________

Do the plants help prevent erosion of the shoreline?.

Is the shore in shade at all during the day?

What is the bottom of the seabed like?

What is the land immediately before the shoreline used for

Has the foreshore been altered by humans at all?

PART C: ABIOTIC FACTORS FOR COMMUNITIES

COMMUNITY 1 – ROCKY

Date 22nd Jan 2009 Time of Sampling 3pm

Trial Water Clarity Reading

(m)

Temperature(oC)

pH Time for Tennis ball to come back to shore from 10m

1 0.20 20 7.2 30s2 0.30 19.5 7.1 20s3 0.25 20 7.2 20s

Average

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COMMUNITY 2 – OPEN

Date Time of Sampling

Trial Water Clarity Reading

(m)

Temperature(oC)

pH Time for Tennis ball to come back to shore from 10m

1

2

3

Average

TASK 2: SAMPLING THE BUGS

Carry out a biological survey of the range and number of the “bugs” for one community by catching and sorting as many bugs as possible from your sampling site.

Identify the different tidal zones as closely as possible. Chose 3 – 5 sampling sites across the range of tidal zones. At each site look for visual evidence of ‘bugs’ and record. Use a net to sweep your sampling site, scraping rocks, and disturbing the

bottom. Empty the net into a tray and allow to settle. Use the identification sheet to group the bugs into the trays provided. Record the number of bugs from each of your sampling sites and add them

together. Calculate the percentage for each bug.

% hermit crab = number of hermit crabs found x 100Total number of bugs

Your identification charts are supplied separately to your booklet. (This is to avoid you dropping your notes in the ocean and waving goodbye to them as they sail to Australia.)

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Rocky Shore Sandy ShoreType of Bug No of

Bugs% Bugs Type of Bug No.

Bugs% Bugs

Barnacle 256

Periwinkle 18

Limpet 32

Sea lettuce 19

Chiton 2

Cockabully 49

Venus necklace 71

Sea anemone 17

Cats eye 75

Mussel 354

Kina 20

Starfish 4

Whelk 15

Sandhopper 20

Cockle 2

Tuatua 0

Toheroa 0

Snapper 0

Paddle crab 1

Sponge 42

Kelp 96

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TASK 3: PROCESSING AND INTERPRETING THE DATA

PART A: USING THE STREAM ENVIRONMENTAL DATA FROM TASK 1

For community 1 and 2, process the data for each environmental factor.

To do this use the invormation from task 1 to complete the following.

1. Water Clarity – calculate the average clarity reacing.2. Temperature – calculate the average temperature for each community.3. pH – calculate the average pH for each community.4. Wave drift speed – calculate the average speed of the water using the formula

below.

Average Speed = Distance travelled (m) x correction factorAverage time (s)

(Correction factor for tennis ball is 0.8)

5. Substrate – record the substrate use for each community from your stream survey.

6. Land use – record the land use for each community from your stream survey.7. Comment on the differences and similarities for each environmental factor.

(write one of these words in the differences column: Same, Similar, Different, Very different)

Environmental Factor Community 1Rocky

Community 2Open

Differences or similarities

Water Clarity (m)

Temperature (oC)

pH

Wave drift speed (ms-1)

Substrate

Land use

PART B: USING THE ‘BUGS’ DATA FROM TASK 2

1. Using the information from the table in task 2, draw a bar graph on the grid overleaf to show the types and percentage of each bug found in community 1.

2. Draw the data from community 2 onto the same set of axes using a different colour.

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TASK 4: DESCRIBING AND COMPARING THE DIVERSITY BETWEEN TWO COMMUNITIES

PART A: Describing the diversity within the two communities.

Write two or three short paragraphs to describe the4 two communities and the pattern of diversity shown.

In the paragraphs you should comment specifically on Similarities and differences of the types and numbers of the bugs.

% of TotalBugs

Type of bug

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PART B: Discussing the diversity within the two communities.

Write two or three paragraphs to discuss the reasons for the similarities and differences between the diversity of the two communities.

This discussion should include. A description of how the abiotic factors affect the bugs. An explanation of how the biotic factors affect the bugs. An analysis of how the land use around the stream affects the water quality and

the diversity within the area. An explanation of the adaptive features of the bugs, that allow them to live in their

environment.

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4 CREDITS LEVEL 2

US21610 – COLLECT, AND USE COMPUTER TECHNOLOGY TO STORE AND PROCESS, NUMERIC DATA FOR A SCIENTIFIC PURPOSE

Your will use the data collected during your field trip to gain unit standard US21610. Please follow the instructions below.

Element 1

Record your ‘bug’ data as you collect it by hand. Transfer your collected ‘bug’ data to the computer.

Element 2

“Tidy up” your data so that it can be used to make a bar graph, to compare the two communities that were surveyed.

Import the pH data from the data logger, and present as a graph, and calculate an average.

Presentation of your data:

Your data will need to be submitted twice.

1. Submit your data with your fieldwork, ensuring that it is clearly labelled and referred to in your write up.

2. Submit your work again with this sheet as a cover sheet. You need to include: The raw data that you collected by hand A print out of the data you entered onto the computer A print out of your tidied up data A print out of your bar graph. A print out of the imported pH data A print out of the pH graph and average.

YOUR NAME____________________________________________

YOUR CLASS___________________________________________

DATE COMPLETED_____________________________________

RESULT

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