Group 4 Project
Bella W, Reni O, Fabio T, Julia B, Dimitrios
S, Sarah S, and Thibault L
Biology
Locations
Process
Sample 1
Slide Sample: 1.1
Stagnant water under bridge (8cm)
Petri Dish Sample 1
Sample 2
LIght stream of water between the rocks (4cm)
Petri Dish Sample 2
Slide Sample
2.1
2.2
Sample 3
Moderate stream under fallen tree (7cm)
Petri Dish Sample 3
Slide Samples: 3.1
3.2
3.3
Sample 4
Moderate stream in the middle of the creek (23cm)
Petri Dish Sample 4
4.1
4.2
4.3
Very light stream by rocks (2cm)
Sample 6
Petri Dish Sample 6
6.1
6.2
6.3
Chemistry
Dissolved Oxygen test
○
Diffused from surrounding air
○ Photosynthesis byproduct
○ Used to analyze the ability to support life
○ Usually used to assess productivity in the stream,
river, lake
Hypothesis
Sufficient for most aquatic species
○ E.g: Salamanders and crawfish
Process
1) Submerge sample bottle
2) Add Manganous Sulfate Solution and Alkaline Potassium
Iodine Azide
3) Shake and mix to form precipitate
4) Add Sulfuric Acid and gently rotate bottle until the solution
has turned yellow
5) Measure out 20 mL of the Water Sample Solution
6) Use titration plunger on Sodium Thiosulphate until scale
reaches 0
7) Add Starch Indicator Solution until the solution turns blue
8) Use Thiosulphate until fixed sample turns clear and record
amount used (ppm)
Collected Data
Sample Location
Oxygen Dissolved (ppm)
1
6.8
2
8.5
3
8.1
4
8.2
5
7.8
6
7.9
Average
7.8
pH Level per Location
Sample Locations
pH level
1
6.76
2
6.81
3
6.86
4
6.85
5
6.90
6
6.73
Average pH Level
6.81
Conclusions
● Average = 7.8 ppm
● Within 7-8 range (sufficient for life)
● Explains animal presence in stream
● pH marginally more acidic, but still basic (6.81)
Evaluation
● Only one trial (lack of time)
● Did not wait for clumps in “fixed” solution
● First trial (closest to source of the stream)
has lowest ppm
Physics
Procedure
● Began at rocks downstream
● 3.5g cork
● Set downstream
● Pre-approximated course
measured with meter stick
● Pick up points 8-10 meters
Data
Time (+/-.5s)
Distance (+/-.2m)
Trial 1
Trial 2
Trial 3
Averages
(approx.) (+/-.5)
8
43
35
30
36
16
62
63
74
67
26
213
212
223
206
36
225
120
125
123
46
99
111
111
107
Approximated Speed at Each Leg
Distance (+/-.2m)
Speed (cm/s)
8
22.2 +/-1.0
16
11.9 +/- 0.5
26
4.6 +/- 0.1
36
8.1 +/- 0.2
46
9.3 +/- 0.3
Projected Data