Introducing 

Prezi AI.

Your new presentation assistant.

Refine, enhance, and tailor your content, source relevant images, and edit visuals quicker than ever before.

Loading…
Transcript

Impact of Abiotic Factors on organisms in Penrith Lakes

By Jennifer Sackprasit

Inquiry Question

Introduction

How does the temperature of water impact the abundance of dragonfly nymphs?

Introduction

Introduction

Through qualitative and quantitative data accumulated through the Penrith Lakes Excursion as well as secondary information, the investigation will focus on how the abundance of dragonfly nymphs will be impacted by changing water temperatures

Background

Background Knowledge

- Located at the foot of the Blue Mountains and eastern banks of the Nepean River

- Formerly a sand and gravel quarry up until 2014 - the government has begun to develop different infrastructure for a healthy lake system and park facilities as part of the Penrith Lakes Scheme.

- Penrith Lakes had been previously impacted by human activity during the 1900s in the Farming Era - individuals had grazed crops and cattle causing run-off to pollute the lake.

Penrith Lakes Environmental Education Centre

Penrith Lakes

Today, the Penrith Lakes Environmental Education Centre (PLEEC) operates within the Sydney Regatta Centre and offers curriculum related fieldwork programs for schools and students in New South Wales.

Aquatic Organisms

Aquatic Organisms

Many aquatic organisms can be found in the lakes on Penrith Lakes. These include:

- Damselfly Nymphs

- Dragonfly Nymphs

- Freshwater Shrimp

- Water Boatman

- Water Mites

among many others

Bird Species

Bird Species

Different species of birds also reside in Penrith Lakes. They can be found among the trees, in the water and flying in the sky. Examples include:

- the Little Black Cormorant

- Australian Grebes

- White-faced Herons

- Purple Swamp-hens

- Australian Wood Duck

Biotic and Abiotic Factors

Biotic and Abiotic Factors

Biotic factors refer to the living organisms being studied throughout the report which are both the aquatic organisms and bird species.

However, abiotic factors refer to the qualities affecting the biotic factors. These include:

- water temperature

- water turbidity

- water pH

- pollution

- wind exposure

and more.

Aim and Hypotheses

Experiments

Aim: The aim of this depth study is to determine the impact of water temperature at Penrith Lakes in relation to the abundance of dragonfly nymphs, using both qualitative and quantitative data

Hypotheses

Biotic: The abundance of dragonfly nymphs will be negatively impacted by the water temperature of the lake in Penrith Lakes.

Abiotic: The external temperature will negatively impact the water temperature at Perith Lakes which will affect the abundance of dragonfly nymphs

Measuring Techniques: Low water temperatures will positively impact the abundance of dragonfly nymphs at Penrith Lakes

Risk Assessment

Risk Assessment

Abiotic Testing

Abiotic Test - Water Temperature

Equipment:

- Digital thermometer (Degrees Celsius)

- Lake water

- Small container

Procedure:

1. Fill small container halfway with the lake water

2. Pick-up the digital thermometer and remove the cap from the bottom

3. Turn the thermometer on

4. Dip the thermometer into the container filled with water until the number being displayed at the top come to a stop

5. Record the results of the experiment in the blue booklet

Biotic Testing

Biotic Testing - Dip Netting

Equipment:

- Dip net

- Large bucket or container

- Sample cups

Procedure:

1. Pick-up a dip net and large container

2. Dip the large container slightly into the lake water so that a small amount of water sits inside the container

3. Place the container down on the ground

4. Sweep the edge of the lake, using the dip-net, randomly to collect species for about 2-5 minutes

5. Tap the specimen out of the dip net using the side of the container so that they fall into the container

6. Repeat steps 4 and 5, for the next 20 minutes in order to collect more specimen

7. Separate each of the specimens into different sample cups - ensure that all the same specimen are grouped together

8. Throw leftover water in the container back into the lake

9. Record the results of the type and amount of specimen collected in the blue booklet

Part B: Conducting

Here, the results of the previous experiments and additional information from the study are provided.

Results

Abiotic Results

Abiotic Factors

Biotic Results

Biotic Factors: Waterbird Observations

Biotic Results

Biotic Factors: Waterbug I.D.

Food Web and Chain

Food Web

The following food web display organisms found throughout the excursion and represent how each organism relies on one another

Food Chains

Analysis

- Abiotic factors of weather and water temperature negatively impact the abundance of dragonfly nymphs

- Conduction of water testing displayed that the average water temp. was 14.5 degrees celsius

- Dragonfly nymphs often found in clean and healthy waters - water in lake was slightly polluted with low turbidity

- Changing seasons showed individuals that many birds were 'hiding away' rather than flying and exposing themselves to the individuals.

- Abundance of dragonfly nymphs and birds ultimately impacted by abiotic factors.

Analysis

Human Impacts

Human Impacts on Ecosystems

- Prior to human activity, Penrith Lakes was filled with native vegetation, native animals and clean water.

- Once humans arrived during the 1900s (a period known as the Farming Era) negative impacts began to occur to the environment

- Run-off sediments and nutrients polluted the water source killing aquatic organisms - increased level of phosphate evident in water

- However, since then, individuals have attempted to 'repair' Penrith Lakes by cleaning the water systems, replanting trees, conserving organisms and plants and more.

- Results from testing and experimentation show that human activity now has improved the quality and health of the ecosystem from the past health

Reliability and Validity

Reliability

- Moderately reliable as it is difficult to determine whether the number of dragonfly nymphs captured was due to water temperature

- Overcast weather, seasonal changes, and inability to investigate other areas of the lake caused the experiment to be less reliable

- Dip-netting experiment only occurred once with limited time - this is a problem as individuals cannot gain accurate results in 20 minutes

-Improvements to be made include providing more time to search for organisms - it would increase the chances of collecting more dragonfly nymphs

Validity

- Experiment moderately valid

- Inconsistent weather impacted the results of experiment as it would cause external temperature and water temperature to change

- Only small area of lake was allowed to be investigated - if individuals were allowed to go further, more specimen would be identified

- Comparison of results between different seasons is necessary as it would conclude whether the abundance of dragonfly nymphs is affected by temperature

- 9 species of birds were identified

- The birds created a habitat in Penrith Lakes and currently reside there - lack of birds seen cause validity to decrease.

Problem Solving

Problem Solving

Conclusion

Conclusion

Abiotic: Hypothesis stated that the external temperature negatively impacted the water temperature at Penrith Lakes which affected the abundance of dragonfly nymphs. This was supported through data collected during the study at Penrith Lakes

Biotic: The hypothesis that dragonfly nymphs at Penrith Lakes were negatively impacted by the water temperature. This hypothesis was supported as the results of the dip-netting experiment display the only one dragonfly nymph was caught. However, the study also proved that additional abiotic factors played a role in affecting the abundance of dragonfly nymphs

Measuring Techniques: The hypothesis referring to measuring techniques stated that low temperatures had positively impacted the abundance of dragonfly nymphs. This was disproved as only one dragonfly nymph was caught on the date of the excursion at a temperature of 14.5 degrees celsius.

Learn more about creating dynamic, engaging presentations with Prezi