Urbanization has negatively impacted the diversity and health of organisms in Reservoir Creek. Upstream areas near residential development had higher temperatures, turbidity, and pollution compared to downstream areas with less development. Upstream sites contained only pollution-tolerant species like worms and midges, while downstream sites contained more sensitive species like mayflies and dragonflies. The changes in abiotic factors from urbanization, such as increased runoff, have disrupted the ecosystem by reducing suitable habitat and food sources for sensitive species. This loss of diversity upstream could impact the whole ecosystem if not addressed.

1. Ecological
Study
Achievement Standard
Science 1.12
4 Internal Credits
Ms Gibellini

2. Achievement Standard
 describes observations or findings;
 uses findings to identify change in environmental
factors; and
 describes how changes in environmental factors
affect organisms.
Uses findings and biological ideas and makes
significant causal links between changed
environmental factors and the ecosystem
characteristics or process including the impact on
organisms and the implications for the ecosystem as
a whole

3. SLO
 Describe the components of an ecosystem, including
abiotic and biotic factors
 Define ecological niche and give examples
 Draw food chains and webs and identify keystone
species and effects of changes on systems
 Describe intra and inter specific relationships within a
community
 Discuss the importance of diversity within a populations
 Identify the impacts humans can have on ecosystems
 Discuss the effects of urbanisation, on the above
factors of an ecosystem
 Carry out measuring of abiotic and biotic factors
 Graph and interpret data

4. Terms
Term Definition
Abiotic Non living
Biotic Living
Ecosystem All the non living and living things within a
large defined area
Population A group of interbreeding organisms
Substrate The ground contents (soil, concrete, sand)
Urbanisation Removal of natural habitat to build
houses, roads, foot paths
Erosion Break down and removal of soil particles
Intraspecific Relationships within the same species
interspecific Relationships between species

5. SLO
 Describe the components of an
ecosystem, including abiotic and biotic
factors

7. Abiotic vs biotic factors
Abiotic
 non living
 Temperature
 Light intensity
 Moisture
 Substrate
 Chemicals/pH
Biotic
 Predators
 Prey
 Courtship and
mating behaviours
 competition

8. Success Criteria
 List the abiotic factors
 School Grounds
 Esby Park
 List the biotic factors
 School Grounds
 Esby Park

9. Success Criteria
 List the abiotic factors
 School Grounds
sand, gravel nearby, housing, high temperature, high light,
high winds, dusty, low pH, low dissolved oxygen, high
turbidity, no leaf litter, little variation to stream shape
 Easby Park
Low light, large rocks, clay, leaf litter, low winds, low
temperatures, high rainfall, high dissolved oxygen, faster
flowing stream, irregular shape and bottom, steep cliff on
side of stream
 List the biotic factors
 School Grounds
Low diversity, snails, worms, grass, flax, algae
 Easby
Mayfly nymphs, stonefly nymphs, damsel flies leaf litter,
freshwater crayfish, native tree – five finger, titoki, beech,
broadleaf, ferns, pungas, fallen trees (rotting) near/on bank

10. SLO
Define ecological niche
and give examples

11. Ecological Niche
An organisms ecological niche includes:
- Where it lives
- What it eats
- Its predators
- Adaptations it has to help it survive
- When its active (day or night)
- https://www.youtube.com/watch?v=xIVixvcR4
Jc

12. Success Criteria
Research and find out:
Describe the ecological niche of
 Mayfly nymph Healthy Stream
 Herbivore, lives under rocks, fast moving water, predators
are fish and birds, active day and night, hooks to hold onto
rocks so doesn’t get washed away, gills so it can breath
underwater, cannot tolerate poor water quality
 Worm Polluted Stream
 Eats mud and plants, breaths through body walls, can
regrow parts, tolerate poor water quality
(Where it lives, What it eats, Adaptations it has to help it
survive, When its active (day or night), what eats it

13. SLO
Draw food chains and webs
and identify keystone
species and effects of
changes on systems

15. Food webs
show all the
food chains
within an
ecosystem

19. Success Criteria
 Write a food chain for
 Healthy stream
Phytoplankton  case caddis  small fish  heron
 Polluted Stream
Detris worms  eel
 How does increasing the amount of leaf litter falling into a
stream affect the food web?
- Overhanging trees drop leaves into stream, increases
numbers of mayflies, caddis, midges and therefore numbers
of stoneflies, small fish, large fish, birds, eels
 How does removing the habitat for nymphs affect the
food web?
- No overhanging trees, no leaves to hide in, digger clears
stream bed, decreases number of nymphs as nowhere to
hide, this decreases diversity (number of species living there
and results in poor stream health and puts the ecosystem at
risk of collapse.

20. SLO
Describe intra and inter
specific relationships
within a community

21. Relationships
Intra specific – within the same species
 Competition
 Mating/courtship
 Parental care
Inter specific – between species
 Competition
 Predation/prey
 Symbiosis - mutualism

22. SLO
Discuss the importance of
diversity within populations

23. Diversity
 Diversity – differences
 In order to survive environmental changes
it is essential that populations have
differences
 Populations with limited diversity are much
more susceptible to extinction

24. Success Criteria
 Describe the diversity above and below
the reservoir?
 What could the council do to improve the
diversity below the reservoir?

25. SLO
Identify the impacts humans
can have on ecosystems
Discuss the effects of
urbanisation, on the above
factors of an ecosystem

26. Human Activities
 Urbanisation – building of houses, roads,
foot paths, construction of pipes
(sewerage, power, water) drainage
 Deforestation – large scale removal of
trees
 Pollution – air, soil, water

27. Impact of Humans on Streams
 Increase erosion – removal of bank
vegetation
 Removal of habitat – artificial channels
 Increased pesticides – runoff from farms,
homes
 Increased nitrates – run off from farms, homes
 Reduce clarity – erosion and run off, storm
water drains
 Reduction in pH – run off from homes
 Increase in sun light and temperature – tree
removal

28. Impact of Urbanisation
 Reduced habitats, loss of riparian zones
 Increased turbidity
 Increased erosion (loss of riparian zones)
 Movement or death of sensitive species
 Loss of key species within food web, leads
to loss of other species
 Reduced diversity
 Rapid changes in river flow

29. Success Criteria
 List the abiotic and biotic factors of
Reservoir stream
 For each state how urbanisation has
affected them

30. 04/03/2015
Pollution Indicators
In dirty water leeches
and midges will survive
In average water more
species (like the
dragonfly and cranefly)
will survive
In clean water a lot
more species (like the
mayfly and caddisfly)
will survive
The quality of water can be monitored by looking
at the species of insect in the water:

31. Terms
Term Definition
Abiotic Non living
Biotic Living
Ecosystem All the non living and living things within a large
defined area
Population A group of interbreeding organisms
Substrate The ground contents (soil, concrete, sand)
Urbanisation Removal of natural habitat to build houses, roads, foot
paths
Erosion Break down and removal of soil particles
Intraspecific Relationships within the same species
interspecific Relationships between species
Riparian Zone 10 m either side of river, abiotic and biotic features

32. Tolerance and Limiting Factors
 Limiting Factors – factor in environment that restrict
growth of an organism
 What are some of the factors that make living in a
stream difficult?
 Carrying Capacity – the number or organism an
environment can sustain

33. Tolerance of Stream Organisms
Aquatic macroinvertebrates are good indicators of
stream quality because:
 They are affected by the physical, chemical, and
biological conditions of the stream.
 They can't escape pollution and show the effects of
short- and long term pollution events.
 They may show the cumulative impacts of pollution.
 They may show the impacts from habitat loss not
detected by traditional water quality assessments.
 They are a critical part of the stream's food web.
 Some are very intolerant of pollution.
 They are relatively easy to sample and identify.

34. Abiotic Factors
For each of the abiotic factors listed, describe how
they might be altered and the effect on specific
(named) marcro invertebrates this change might
have:
- Stream flow
- Dissolved Oxygen
- Temperature
- pH
- Turbitidy
- Substrate

35. Stream Flow and Dissolved Oxygen
 Sped up by concreting the sides of the chanel,
removing debris, daming and releasing water
upstream, how water level
 Slowed down by reducing water level, increasing
debris,
 Fast flowing water brings in but can also wash
away food, silt and debris
 Fast flowing water tends to have a higher oxygen
content and lower temperature
 Macro invertebrates that breath using gills
(mayflies, stoneflies, dobsonflies) need to have a
constant fresh supply of oxygenated water
 Snails prefer slow moving water with lots of algae
to feed on

36. Temperature
 Temperature is affected by the flow of the stream,
the amount of bush overhanging the stream and the
time of the year
 Temperature also affects the amount of dissolved
oxygen in the water, the warmer the water the less
oxygen it holds
 Low temperatures can slow the metabolism of some
macro inverts
 High temperatures can also kill some macro inverts

37. Substrate

38. Turbitidy

39. Two sites at a lake
were sampled.
One site was near
a popular camping
spot, the other site
part way around
the lake where
access was more
difficult.
Biological Impact
Practice Question
Site near camping spot
Second site

40. Macroinvertebrates found
Camping Site Sensitivity
Score
Isolated Site Sensitivity
Score
Worms – 7 1 Mayflies – 3 4
Crustaceans –
2
2 Dragon flies – 2 3
Midges/sandfli
es – 8
1 Midges/sandflie
s – 7
1
Snails -5 2 Crustaceans – 3 2
Caddis fly – 4 3
Water beetles -
2
3
Damsel flies – 4 3
Total found =
22
Total found = 23

41. Practice Question
Describe the abiotic and biotic factors
for the two sites
List organism found
Why are some organism found at one
location and not the other?
What impact does the lack or over
population of certain organism have
on the ecosystem as a whole?

42. Internal Assessment
Task 1 – Collect data
Task 2 – Process Data
- tabulate data, graph it, average
- calculate tolerance
Task 3 – Write a report on effects of abiotic
factors on biotic factors

43. Data Processing
Develop a table to record the similarities and
differences in the environmental factors in the two
areas of the freshwater ecosystem. For some
factors averages for each area may have to be
calculated:
Location Temp Turbidity Dissolved
O2
Light
Level
pH Substrate Speed
of Flow
Pollution
Tolerance
Rating
Healthy
Stream
17’C +1m 14 mgL-1 Low/m
ed
7.2 Fast
Polluted
Stream
14’C +1m 10 mgL-1 V. High 7.8 Slow

44. For each area of the freshwater ecosystem, calculate the
percentage of the total present for each macro-
invertebrate.
To do this, divide the number of macro-invertebrates in
the area by the total number of macro-invertebrates
found in that area.
eg. % mayflies = number of mayflies found x 100
total number of macro-invertebrates
Record this information in a table and draw a bar graph
to compare all the data from each of the two areas.

45. Calculate the pollution tolerance index for each area and determine the water
quality of each area.
The Pollution Tolerance Index (PTI) uses indicator organisms and their tolerance to
pollution (called a sensitivity score) to give an assessment of water quality. To
calculate the pollution tolerance index for each area multiply the number of types
of organisms in each tolerance level by their sensitivity score (4, 3, 2 or 1).
For example:
In a sample that contains mayflies (tolerance score 4), stoneflies (tolerance score 4),
caddis fly (tolerance score 3) and some diptera (tolerance score 1), the calculation
would be:
2 x 4 (2 different types of organisms each with tolerance scores of 4 ie Mayflies
and
stoneflies)
+ 1 x 3 ( 1 type of organism with a tolerance score of 3 ie caddis fly)
+ 1 x 1 (1 type of organism with a tolerance score of 1 ie diptera).
Pollution Tolerance Index = (2 x 4) + (1 x 3) + (1 x 1) = 8 + 3 + 1 = 12

46. PTI Value Water Quality
Rating
23 and above Excellent
17 – 22 Good
11 – 16 Fair
10 or less Poor
Now compare your calculated pollution tolerance index (PTI) with
the scale below:

47. PTI
Pollution tolerance indicator tells us how
many different kinds of species are found
The more species, the more diverse, the
healthier the river
It also tells us how many pollution sensitive
organisms are found
The more pollutant sensitive species, the
higher the PTI and therefore the healthier
the stream

48. Your task:
1. Calculate the Pollution Tolerance index
at each site and find out the water
quality.
2. Calculate the percentage of the total
for each species at each site and draw
a bar graph of this data for each site.
3. Write a paragraph about the health of
the lake at the two different sites,
based on what we have learned.

49. Reporting
Use your observations and finds from Tasks 1 and 2
and biological ideas about ecology to write a report
on the impact of urbanisation on water quality and
the diversity of organisms in a freshwater ecosystem.
In the report:
Use all your findings and your own ideas to make
significant causal links to explain the impact of
urbanisation on the two areas studied along the
Reservoir creek. The effects on the stream may be
differing environmental factors (including water
quality) which may have had implications for the
ecosystem as a whole.

50. Report Format
Introduction
 Describe what an ecosystem is
 What is urbanisation
 When urbanisation started and how much residential
development has occurred down the Reservoir
Creek.
 Map (of entire length of stream) and names of
locations you will be discussing

51. Method:
 Briefly outline what you did/how
you collected data, where,
Results:
 Put your tabulated results here
 Graphs
 Put your profile diagram here
 Include a few pictures – you
need to say what they show

52. Discussion
 Describe abiotic and biotic features of both areas
 Discuss how they are different
 Discuss what has caused the differences in both abiotic and
biotic features (urbanisation)
 How does urbanisation affect streams? (ie increases run off)
 What are the general impacts of urbanisation on streams
 Why is diversity important to ecosystems
 The fauna (animals) and flora (plants) that made up the
Reservoir Creek ecosystem before any urbanisation.
 Specifically link environmental changes to changes in species
found
 Discuss the importance of these differences on the ecosystem
as a whole (diversity)
 Use actual data from your tables to illustrate changes,
 You need to discuss differences between the two sites
surveyed.
 Your discussion must be related to the effects on the
ecosystem due to urbanisation.

53. Excellence:
Abiotic Factor  Link  Biotic Factor  Ecosystem
(because) (causing) (resulting in)
Effect  Cause  Result  Impact on Ecosystem as a whole
Eg.
High temp  Trees removed (no shade)  reduced oxygen in
water, loss(migration or extinction) of some macro invertebrates
as they prefer cooler water  reduces diversity in ecosystem and
puts whole ecosystem at risk
(Remember to compare this with above the reservoir)
Flash Flooding  narrowing of stream channel, increase run off
due to urbanisation  removal of food source and macro
invertebrates  reduces diversity in ecosystem

54. Conclusion:
Summarise the body
- using biological ideas to make significant
causal links between the changed
environment factors and ecological
characteristic or processes to explain the
impact on organisms and the implications on
the ecosystem as a whole
- How has the river changed and what caused
the change and what are the long term
implications of this change?
- Suggestions of what could be done to improve
the stream

55. Achievement Standard
 describes observations or findings;
 uses findings to identify change in environmental
factors; and
 describes how changes in environmental factors
affect organisms.
Uses findings and biological ideas and makes
significant causal links between changed
environmental factors and the ecosystem
characteristics or process including the impact on
organisms and the implications for the ecosystem as
a whole