Name: / School:
Other members of your group:

Start with some general observations.

Site description

Lake: / Nearest City:
Longitude: (eg Penrith Lake is 151°E) / Latitude: (eg Penrith Lake is 34°S)
Today's date: / / / Time:

Tick what you can see

/ pollution / /
rubbish
/ / fish / / birds / / algae / / weeds

Type of waterway

/ pond / /
river
/ / lake / / dam / / stream

Describe the weather

/ clear / /
partly cloudy
/ / cloudy / / hot / / cold / / rain

Surface of the water

/ calm / /
small ripples
/ / waves / / choppy / / heavy swells

Development around the lake

/ paddocks / /
wetlands
/ / roads / / houses
Describe the look of the water
/ muddy / /
clear
/ / cloudy
Is there a smell?
/ no / /
yes
Activity 1: Temperature
Carefully approach the edge of the water and place the thermometer 10 to 20 centimetres under the surface. Leave for three minutes. Then record the result in degrees Celsius (°C). Repeat three times.
Temperature 1 = °C
/
Temperature 2 = °C
/
Temperature 3 = °C
/
Average = °C
Was the temperature suitable for living things? Yes (15 -35°C) No (less than 15, more than 35°C)
Activity 2: pH
Take a water sample away from the edge of the water and below the surface. Test the pH straight away. Place the pH meter into the sample in the cup. Record your results.

The pH of the lake was

The pH shows that the health of the lake was:

/ poor (5.5 or less) / / average (5.5 - 6.5) / / good (6.5 - 8.0) / / average (8.1- 8.5) / / poor (8.6 or more)

Activity 3: Turbidity

A turbidity tube is a long clear tube with a pattern in the bottom. Take a water sample using a bottle. Shake the bottle and then slowly pour the water into the tube until the pattern on the bottom disappears when you are looking from the top. Read the value below the water level. Do not average the values or make a guess between the levels. Record your results. Repeat three times.

Turbidity 1 = NTU / Turbidity 2 = NTU / Turbidity 2 = NTU / Turbidity range = NTU

The turbidity shows that the health of the lake was:

/ low (less than 10) / / medium (15 to 30) / / high (greater than 30)

Activity 4: Dissolved oxygen (Wear gloves and goggles for this experiment!)

Collect your water sample away from the edge and below the surface. If you get any air bubbles this may give you a higher reading. Fill the tube completely under water and put the lid on before bringing the bottle to the surface. Test right away using the dissolved oxygen TesTabs. Drop two oxygen tablets into the tube. Screw the cap back on and place your finger over the top. Mix by shaking (4 minutes) and turning upside down until the tablets dissolve. Leave for another five minutes. Compare with the colour code chart. Repeat the test or use the results from other groups.

The dissolved oxygen was (ppm).

The dissolved oxygen result shows that the health of the lake was:

/ poor (0 ppm) / / average (4 ppm) / / good (8 ppm)

Activity 5: Phosphate (Wear gloves and goggles for this experiment!)

Fill the test tube to the 10 mL line with water. Add one Phosphorus TesTab. Put the cap on and mix by turning upside down. Wait five minutes for the blue colour to develop. Compare it to the colour chart. If there is no blue colour record the result as 0 ppm (parts per million).

Phosphate was (ppm). The phosphate reading shows that the health of the lake was:

/ excellent (1 ppm) / / good (2 ppm) / /

average (4 ppm)

Identification sheet

Tick off the macroinvertebrates in the table and then total the pollution index.

Using macroinvertebrates to estimate the health of freshwater

Very sensitive
/ caddisfly larva (10)
/ / mayfly nymph (10)

Total for very sensitive=
Sensitive
/ water mite (6) / / beetle larva (6) / / dragonfly nymph (4) / / water strider (4)
/ nematode (4) / / whirligig beetle (4) / / damselfly nymph (4) / / amphipod (4)
Total for sensitive=
Tolerant
/ flatworm (3) / / freshwater mussel (3)
Total for tolerant =
Very tolerant
/ midge larva (2) / / mosquito larva 2) / / diving beetle (2) / / water scorpion (2)
/ backswimmer (2) / / boatman (2) / / bloodworm (2) / / pond snail (1)
Total for very tolerant =

Pollution index total =

When you reach a total you can work out the health of the stream from the table below.

Pollution index / Health of stream
0-20 / poor
21-35 / fair
36-50 / good
more than 50 / excellent

The health of the lake was ______.

Method

1.  Select a place to sample that is easy to recognise and is not dangerous.

2.  Dip the net through the water and the water plants. Use a long slow sweeping action.

3.  Search for 15 minutes (use a stopwatch or watch with a timer)

4.  Fill the ice-cream container or tray with water from the lake.

5.  When you catch any macroinvertebrates place them in this container.

6.  Look under any rocks in the water, remember to replace the rocks.

7.  Look for organisms on the surface of the water.

8.  Disturb the bottom of the water to stir up any macroinvertebrates.

9.  When you have caught some macroinvertebrates separate them into different species (types) using the ice cube tray.

10.  Identify the species using the Identification sheet on the next page.

11.  Tick off the macroinvertebrates in the table.

12.  The pollution index is in the table. Work out the pollution index for the lake.

13.  Select macroinvertebrates to take back to the lab for microscopic examination.

14.  When you finish, carefully return the other organisms to where you found them.


Observations of living things: Instructions.

1.  Sit quietly for 15 minutes and record any living organisms that you see.

2.  Go for a timed walk of 10 minutes and look for living things.

3.  Look under any rocks but remember to replace rocks.

4.  Look for organisms on the surface of the water.

5.  Use a digital camera or make some drawings to record any organisms that you see.

6.  Divide the organisms into producers and consumers.

7.  Then divide the consumers into herbivores, carnivores and omnivores.

8.  Start working out any food chains that might exist.

9.  Ask members from the other groups what organisms they have found.

Producers (plants)

Growing underwater (submerged)

/

ribbonweed

/ / algae / / curly pondweed
Sticking out of the water (emergent)
/ common rush / /

cumbungi

/ / umbrella sedge / / other reeds
Floating
/ duckweed / /

azolla

Introduced
/ alligator weed / / water hyacinth /

Consumers

Water birds

/ swamphen / /

cormorant

/ / wood duck / / heron / / cattle egret

Terrestrial birds

/ magpie / /

plover

/ / galah / / willie wagtail / / swallow / / dove
/ currawong / /

rozella

/ / raven / / cockatoo / / pigeon / / finch
Amphibians
/ frog or tadpole
Reptiles
/

lizard

/ / snake / / turtle

Arthropods

/ ant / /

spider

/ / beetle / / butterfly / / dragonfly / / bee

Mammals (list any mammals you see)

Food chains

Try to make up some of your own. Remember, start with a producer, then a herbivore and a carnivore.

Science @ the lakes