Senior Biology

A Local Ecosystem – A study of an Open Forest

587 Chapel Hill RoadSackville North NSW 2756

Phone: 4579 1136 Fax: 4579 1072

www.brewongle-e.schools.nsw.edu.au

1

Health and Safety Issues As you are working out in the field you need to be aware that:

Ground material is often covered in moss and can be very slippery. Vines and dense undergrowth can trip. Fallen trees can be rotten and weak. Some animals can deliver painful or venomous bites. On slopes, rocks can be easily dislodged. Edges of wetlands can be quite deep and muddy.

Preliminary Course Outcomes covered by the Field WorkP2 Applies the processes that are used to test and validate models, theories and laws

of science, with particular emphasis on first-hand investigations in Biology.

P4 Describes the applications of Biology which affect society or the environment.

P7 Describes the range of organisms in terms of specialisation for a habitat.

P8 Analyses the interrelationships of organisms within the ecosystem.

P11 Identifies and implements improvements to investigation plans.

P14 Draws valid conclusions from gathered data and information.

P16 Demonstrates positive values about and attitudes towards both the living and non-living components of the environment, ethical behaviour and a desire for a critical evaluation of the consequences of the applications of science.

History of the Study SiteThe forest is located at Sackville North adjacent to the Hawkesbury River. The natural vegetation of the area has been largely modified by farming practices and at present is grazed by horses and cattle.

The land was originally inhabited by the Darug Aboriginal nation and presumably was not greatly altered during that time. The Sackville – Windsor area was considered suitable for farming and was settled in 1810. The vegetation was severely modified following settlement. This was initially restricted to the flood plain immediately adjacent to the river.

Wetlands along the floodplain such as the lagoon adjacent to the study site were, and are, habitats for waterfowls, fish, various reptile and amphibian. While much of the land adjacent to the river and lagoon has been cleared it is most likely that it was once dominated by River Oaks (Casuarina cunninghamiana, Hawkesbury Blue Glum (Eucalyptus deanei), Turpentine (Syncarpia glomulifera) and Paperbarks (Melaleuca styphloides).

The willows and poplars near the lagoon were introduced around the 1960’s and 70’s for riverbank stabilization and farming. In recent years the property owner has used grants from the National Heritage Trust to construct fences to exclude cattle from sensitive areas on the property.

2

Investigation ScenarioThe Task: Background

The study site is a 180 acre property located at Sackville North NSW and has recently been purchased by a city couple keen to pursue their own bush experience. Mr and Mrs Turnbull are avid bird watchers and are particularly interested in owls. Now that they are located along side larger tracks of bushland they have heard anecdotal evidence that Australia’s largest owl – the powerful owl inhabits the area.Mr and Mrs Turnbull have employed your company ‘Naturally Ninox’ to prepare a consultation report on the forest and the likelihood it could support a population of this nocturnal species.

Student Task

Establish parameters for the Powerful Owl’s survival.

Test the study site for its ability to support Powerful Owls.

Interpret results and make conclusions based on findings.

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Let’s study the Powerful Owl

What type of firsthand investigation methods could you use in the field to complete this study and what equipment or resources do we need?

4

Powerful Owl

Where do they nest?

What is their diet?

What type of ecosystem do they require?

Survey Recording FormAbiotic Components

Physical & Chemical Characteristics Along the Transect

Method Site 1 Site 2 Site 3

Soil

Temperature Remove the cover from the thermometer and place probe in soil.

Colour Rub fore fingers on ground & colour in the worksheet section

pHStep 1-Place soil on white tray with spoonStep 2-Place 2-3 drops of universal indicator over the sampleStep 3-Sprinkle barium sulphate on sampleStep 4-Use colour chart to assess pH level

Texture See notes on pink laminated sheet

Leaf Litter Depth

Place trowel into leaf litter. Take measurement from centre of trowel

Air

Temperature Use the temperature meter

% MoistureUse hygrometer.Step 1-Read dry bulb temperatureStep 2-Read wet bulb temperatureStep 3-Calculate difference between wet & dry bulb temperaturesUse chart in centre to assess relative humidity

Light IntensityUse lux meter. 1 lux = light of one candle per square meter.Turn on to x100 & take a reading from waist height (add two zeros to your reading)

Geography

Slope Use clinometer. (blue colour) (in degrees)

AspectUse compass.Step 1-Assess where north isStep 2-Assess direction of transect line

Elevation Will be given to you

Lithology Assess the rock type observed

Abiotic results – interpretation sheet Site 1 Site 2 Site 35

H=HealthyU=Unhealthy

H=HealthyU=Unhealthy

H=HealthyU=Unhealthy

Soil

Temperature What would soil temperature influence?

Salinity 0ppm = unhealthy 0-140ppm = healthy >140ppm = unhealthy

pH 1 – 5.5 = unhealthy 5.5 – 8 = healthy 8 – 12 = unhealthy

Texture How would the texture influence vegetation?Leaf Litter

Depth<1cm = unhealthy 2 – 3cm = adequate 3cm & above = healthy

You will need to use internet resources like the Bureau of Meteorology to answer some of the following

Air

Temperature What is the average temperature range for the month for Sackville North?Does your recorded temperature fit within the average?

Light Intensity

<100 lux = very dark day Full daylight = ~10,000 lux Bright sunlight = ~100,000 luxDid your lux readings vary as you moved along the transect?Why?

% MoistureWhat is the average humidity for the month at Sackville north?How does your recorded humidity compare to the average?

Geography

Slope How would the slope influence vegetation?

Aspect How would the aspect of the slope change the type of vegetation?

ElevationDoes the vegetation change as you move up the slope?Why/why not?

Lithology Why are we interested in the type of rock observed?

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Survey Recording Form VEGETATION TYPE AND HEIGHT Biotic Components – Cross section Plant Distribution Along the Transect Transect 1

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DistributionDistribution of a species describes where it is found. A transect can be used to measure distribution. Follow your 30m transect and record tree species and tree height on the table below. Draw a line for each tree with a symbol at the top that represents species.

Transect 2 Transect 3

Key to Flora# = Paperbark

= Blue Gum= Lilly Pilly= Pittosporum= Grey Myrtle= Rough B.

Apple= Coachwood= Turpentine

Example What is the vegetation classification? ____________________________________

(To complete refer to ‘Vegetation Classification by Structure’ sheet)

Powerful owls prefer trees 40m and above to make shelter/nests. Did you observe/measure any trees of this height at the study site?______________

Plant AbundanceAbundance refers to the number of species in a given area. This may involve counting actual species but if the area is too large, sample plots or quadrats are used to estimate overall abundance.

PLANT NAME Quadrat 1 Quadrat 2 Quadrat 3Average

(amount per 100sqm)

TOTAL ABUNDANCE (amount per 100,000 sqm)

(average result x _________?)

PaperbarkMountain Blue GumLilly PillySweet PittosporumGrey MyrtleRough Barked AppleCoachwoodTurpentine

How could this data affect the presence of a population of Powerful Owls? _____________________________________

Study Site = approx. 100,000sqm

You will be counting tree species in 10m x 10m quadrats (100sqm).

You will then need to estimate total abundance of each species for the whole site (100,000sqm)

The average results for each quadrat by will be multiplied by_______________ to find total abundance of each species for the study site.

Are there any site factors that could make this figure inaccurate?_______________________________________________________

HABITAT ASSESSMENTHabitat Element

SITE 1

SITE 2

SITE 3

TREE

S

Trees 1 - 3 large trees (> 6m) 1 More than 5 large trees

2One or more trees native to Australia 2

A variety of 4 or more plant species 2

Healthy Tree Canopy / Plant Foliage

Healthy 2

Moderately Healthy

1

Defoliation Evident

0

Evidence of Dieback

0

SHR

UB

S Shrubs None 0

Some 1

Most 2

Native Shrubs None 0

Some 1

Most 2

GR

OU

ND

C

OVE

RS Ground Cover None

0Some

1Most

2

Native Grasses or Spreading Plants 2

SHEL

TER

HollowsButt

Hollows 1

Limb Hollows

1

Fallen Log Hollows

1

Rocks & Crevices None 0

Some 1

Most 2

Leaf Litter None 0

Some 1

Most 2

Loose Bark (attached or shed)

None 0

Some 1

Most 2

Logs & Fallen Branches

None 0

Some 1

Most 2

WA

TER

Pond/Water Yes 1

No 0

FOO

D Plants with Fruits / Seeds

None 0

Some 1

Most 2

HA

BIT

AT

SPA

CE Plants of Different

AgesNone

0Some

1Most

2

SU

RR

OU

ND

ING

LA

ND

SC

AP

E Joined or Located to Other Gardens / Bush

by Gardens / BushYes

1No 0

TOTAL SCORE / 33

Sh ru bs

A powerful Owl requires a minimum score of 20 to survive.

A LOW SCORE WILL INDICATE THE ZONE IS POOR HABITAT.This may be because it has been disturbed or requires

additional habitat parameters to better support the amazing variety of living things.

INTERPRETING THE HABITAT ASSESSMENTTREES - provide nesting sites and food for nectar and fruit eaters.

HEALTHY TREE CANOPY – a healthy canopy will indicate the site is relatively free of human disturbances (eg; erosion, compaction) or natural disturbances (storm damage, major presence of mistletoe)

SHRUBS – dense native shrubs allow small native animals and birds to shelter and to hide from predators such as feral cats.

HERBS & GROUND COVERS – provide the food for finches, lyrebirds, lizards, frogs and wallabies, and also provide habitats for small mammals, insects and spiders.

NATIVE PLANTS – native plants are adapted to the Australian environment. They require less watering, little or no fertiliser and provide the right food at the right time for the native animals that have evolved with them.

HOLLOWS – are important homes for native wildlife. It can take over a hundred years for hollows to develop in forests. Hollows also provide nesting sites for birds, possums and bats.

ROCKS & CREVICES – provide habitat for many animals to live and feed and for certain species of plants to grow – they are valuable habitat. Bush rock collection has had a significant impact on our wildlife and degraded many areas.

LEAF LITTER – provides habitat for smaller animals like lizards, geckos, frogs and invertebrates. Leaf litter, when broken down, provides humus – a rich source of nutrients for trees and shrubs.

LOOSE BARK – provides habitat for invertebrates, spiders and lizards.

LOGS OR FALLEN BRANCHES – 20% of native mammals need logs to nest in. They provide habitat for invertebrates and reptiles. When they decay they provide nutrients for the ecosystem.

POND / WATER – provides homes for frogs, native fish, dragonfly nymphs and other invertebrates. Also drinking water for birds and animals.

PLANTS WITH FRUIT / SEEDS – an important source of food for birds, bats, possums and invertebrates.

PLANTS OF DIFFERENT AGES – indicates that an area has more habitat spaces for a variety of plants and animals.

JOINED OR LOCATED TO OTHER GARDENS / BUSH – a variety of vegetation, vegetation density and landscapes will allow a greater range of animal species to find food and nesting sites.

References – Rumbulara EEC CRAM Project – CMA,Windsor

Human Impacts on a Vegetation CommunityThere are many ways in which a vegetation community can be disturbed and each disturbance can have a varying degree of impact.

Observe the vegetation community around you to complete the following checklist.

1. Has the soil been disturbed by;None (o) minor (1) major (2)

erosion (sheet, rill, gully) mining of soil, clay or sand dumping of rubbish/garden waste bushrock collection access roads, paths or tracks

2. Has the vegetation been disturbed by;None (o) minor (1) major (2)

weed invasion logging past clearing off road vehicle use nutrient/sewage seepage from adjacent farmland

3. Is the site;No (0) Yes (2)

adjacent to an urban area adjacent to recreational facilities showing evidence of feral animals

Score:Poor = 21 - 30 Recorded score: Average = 11 - 20Good = 0 - 10

Observe as many alterations to the vegetation community at the study site.Alteration Environmental Impact

NB the Powerful owl requires a score of 0-10 to survive.

Use the ID Charts to choose any 5 plants from the list below to determine the availability of food sources for ringtail possums throughout the year.

PLANT NAME HABITAT & HEIGHT

FLOWERING TIME ADAPTATIONS

Mountain Blue Gum

Eucalyptus deanei

Lilly Pilly

Syzygium smithiiDrip tip leaves

Sweet Pittosporum

Pittosporum undulatum

Grey Myrtle

Backhousia myrtifolia

Rough Barked Apple

Angophora floribunda

Coachwood

Ceratopetalum apetalum

Turpentine

Syncarpia glomulifera

Timber very

resistant to fire

Salt water durable

Paperbark

Melaleuca styphelioides

Use the ID Charts supplied to complete the following tables for the species below.

Common Ringtail Possum(Pseudocheirus peregrinus)

Distribution

Habitat

Diet

Adaptations

One of a few marsupials able to feed on eucalypt leaves which are a poor source of nutrition. The gut has a large colon and a very large caecum in which masticated food is fermented by bacteria. During the day whilst in the nest the contents of the caecum are evacuated as soft faeces and immediately eaten. Hard faeces derived from material which has been digested twice is produced at night.

Powerful Owl(Ninox strenua)

Distribution

HabitatMountains forests and scrubs.Has several favoured roosts in trees 10-40m for the ground.

DietMammals (mainly possums and gliders)Occasional birds

Adaptations

Most adaptations are for hunting.They have round heads capable of an extraordinary degree of rotation.Noiseless flight- flight feathers have soft edges to facilitate silent flight.Hooked beakPowerful talons with sharp claws

Conclusions1. Are there enough food sources throughout the year to support a population of ringtail possums?

_______________________________________________________________________________

2. What evidence do you have to support this? ________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

3. Are there enough habitat space requirements for a population of ringtail possums? __________

4. What evidence do you have to support this? ________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

5. Are there potentially enough habitat space requirements to support the powerful owl? _______

6. What evidence do you have to support this? ________________________________________

______________________________________________________________________________

______________________________________________________________________________

7. Is the study site joined / connected to other forest ecosystems? _________________________

8. What are the implications for the powerful owl? ______________________________________

_______________________________________________________________________________

Recommendations1. Are there any environmental issues impacting on the biodiversity of the study site? __________

_______________________________________________________________________________

_______________________________________________________________________________

2. Outline sustainable management practices Mr and Mrs Turnbull could incorporate at the study site to support a population of the powerful owl into the future. __________________________

_______________________________________________________________________________

_______________________________________________________________________________

______________________________________________________________________________

_______________________________________________________________________________

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DEFINITIONSabiotic the non-living components of an ecosystem (soils, climate, air, water)abundance the number of species in a given area

adaptation a genetically determined characteristic of form, function or behaviour that makes an organism suited to live in its environment

autotroph an organism that is able to synthesise organic matter from inorganic nutrients and a source of energy. most plants and some bacteria are autotrophs

allelopathy allelopathy literally means “hurting each other” and in plant biology refers to the chemical by-products of one plant inhibiting the growth of another

biomass the mass of living matter in a particular areabiosphere the life-supporting layer of the earth extending from the upper atmosphere into

the soilbiota the living component (both plants and animals) usually of a particular regioncommensalism a close relationship between two organisms such that one derives food and/or

shelter from the othercommunity an assemblage of interacting populations of plants, animals, bacteria and fungi

sharing a common environmentcompetition the striving for the use of common resources between or within speciesconsumer and organism that feed on other organisms (plants or animals) or on organic

matter (dead organisms, detritus)distribution the geographic occurrence of a population or speciesdiversity the number of species in a given areaecology the study of ways that organisms interact with each other and with their abiotic

environmentecosystem a system of ecological relationshipsenvironment all the living and non-living components that constitute and organisms

surroundingsepicormic buds dormant organs of vegetative growth on a stemeutrophication the enrichment of lakes and waterways as a result of the leaching of nutrients.

this often causes an excessive growth of aquatic plants. it is commonly produced by effluents such as fertilisers and sewage

exotic a plant or animal introduced form another regionfood chain a simple series representing the transfer of food and energy from plants through

herbivores to carnivoresfood web a net of interwoven food chainsforest a plant community dominated by trees where the canopy of the trees shades

more than 30% of the ground

genus a taxonomic group of closely related species eg. Eucalyptus, Acaciaherbivore an animal which feed upon living plantslarva the immature form at birth or hatching of some groups of animals such as insects,

molluscs and frogs, requiring metamorphosis to reach adult formmicro climate the meteorological conditions, or climate, in a small areamicro habitat the different parts of the habitat that an individual encountersmutualism symbiosis which advantages both speciesniche the place or role of an organism in a community; all the components of the

environment with which an organism interactsorganism any living thingparasite an organism that consumes part of the tissue of its hostperennial a regular event; usually an herbaceous plant or shrub which lives from year to

yearphotosynthesis production by plants of organic compounds from water and carbon dioxide using

energy absorbed from lightquadrat a sampling frame, or an area marked out for sampling flora and fauna in a study

arearespiration breathing; the oxidation of organic molecules within a cell to release energysclerophyll hard-leathery leaves that aid in moisture retention – usually applied to eucalypt

forests and woodlandsspecies a group of similar individuals that are capable of interbreeding and producing

fertile offspringsuccession the process by which one plant community replaces anothersymbiosis usually refers to a mutually beneficial relationship between species, but may

include parasitism and commensalismterrestrial relating to the landtransect a line or narrow strip, used in censuses of organisms in a given areatranspiration evaporation of water from plants, usually the leavestrophic refers to nutritiontrophic level position in the food chain; primary consumers (herbivores) are on the first trophic

level, secondary consumers (carnivores) are on the second or third levelswetland an area of low lying land that is irregularly, regularly or permanently covered with

either fresh or salt waterwoodland plant communities dominated by trees whose canopies shade less than 30% of

the ground

Definitions drawn substantially from A Natural Legacy, Pergamon 1986