The Effects of Acid
Rain on Algal Growth
Alex Zapinski
Pittsburgh Central Catholic
PJAS 2015
Grade 9
Acid Rain
!  Contains
high amounts of nitric and sulfuric acids
!  Created
by emissions of sulfur dioxide and
nitrogen oxides.
!  Emissions
come from both natural and man made
factors
!  Can
be deposited onto the earth in two forms: dry
and wet deposition
Algae
! Large
and diverse group of eukaryotic
organisms, typically autotrophs
! Base of all aquatic food chains
! Used
as a bio-indicator for aquatic
ecosystems
Euglena gracilis
!  Generally
!  Common
cylindrical in shape with many flagella
algal like protist
!  Partial
heterotroph- endocytosis and
photosynthesis
!  Capable
of surviving in both salt and freshwater
ecosystems
!  A
common lab subject
Spectrophotometry
! Measures
the amount of light that
passes through a medium at a set
wavelength
! Commonly
used in physics, chemistry,
biochemistry, material science, and
molecular biology
Past studies
!  Some
limiting factors such as sulfuric acid can
cause algal blooms
!  Algal
blooms can lead to the deoxygenization of
the pond and death of other aquatic life
!  High
concentrations of sulfuric acid have been
shown to be a hindrance to the growth of algae
Interaction of Components
!  Algae
in nature is commonly affected by acid
rain, which can have devastating effects on
the surrounding environment
!  The
sulfuric acid affects the growth of the
euglena
!  The
spectrophotometer is used to measure the
growth of the algae
Purpose
! To
determine if sulfuric acid has
significant effects on the growth of
Euglena gracilis.
Hypothesis
!  Null
hypothesis- the sulfuric acid will not have
significant effects on the growth of Euglena
gracilis
!  Alternative
hypothesis- the sulfuric acid will
have significant effects on the growth of
Euglena gracilis
Materials
!  Euglena
gracilis
!  35 test tubes (13 x 100 mm culture tubes
borosilicate)
!  Micro-pipettes
!  Micro-pipette tips
!  Spectrophotometer
!  Test tube racks
!  0.1 M sulfuric acid
!  Spring water
!  Soil water
Procedures
1. Racks with tubes were set up on a desk 46 cm
away from a lamp.
2. The temperature of the room was set to 20-21
degrees Celsius.
3. The following ingredients were added to the
tubes to create the following experimental
concentrations of sulfuric acid.
Tube concentrations (mL)
Molarity 10-2
10-3
10-3 Substock 10-3 Substock
Control
0
10-4
10-5
Sulfuric
Acid
0.5
0.05
0.5
0.05
0
Euglena
1
1
1
1
1
Soil Water
1
1
1
1
1
Spring
Water
2.5
2.95
2.5
2.95
3
Total
Volume
5
5
5
5
5
Procedures (cont.)
4. The top of each tube was covered with wax paper
and mixed by inversion.
5. The absorbance was taken at 430nm using a
spectrophotometer.
6. Absorbance readings were taken every two days
for 14 days.
Anova: Single Factor
!  Analysis
of data that compares variation within
groups to variation between the groups
!  Alpha:
!  If
0.05
the p-value is below the alpha, then the
effects are significant
430nm
P-values:
Day 1: 0.3795
Day 3: 10-13
Day 7: 10-11
Day 13: 10-22
Dunnett's Test
!  Compares
experimental groups back to the
control
!  Determines
which experimental groups
produced significant variation
!  If
T value > T-crit then the results were
significant
T-crit= 2.689 10-2
Sulfuric Acid
10-3
10-4
10-5
Day 3
T-value
12
5.1
.632
1.288
Significance
Significant
Significant
Not Sig.
Not Sig.
Day 7
T-value
Significance
13.748
4.208
0.705
2.114
Significant
Significant
Not Sig.
Not Sig.
Day 13
T-value
Significance
29.2599
9.592
9.11
4.69
Significant
Significant
Significant
Significant
Conclusion
!  Null
hypothesis would be rejected for the
concentrations of 10-2 and 10-3
!  Null
hypothesis would be accepted for the
concentrations of 10-4 and 10-5 except for
day 13
Limitations and Extensions
! Limitations!  Health
of Euglena?
!  Controlled temperature
! Extensions!  Use
more species of algae
!  Use more replicates
!  Use more concentrations of sulfuric acid
!  Use concentrations of nitric acid
!  The synergistic effects of sulfuric acid and
other chemicals
Works cited
!  http://www.epa.gov/acidrain/index.html
!  http://www.physics.ohio-state.edu/~kagan/
phy367/P367_articles/AcidRain/effects-onlakes.html
!  http://www.fcps.edu/islandcreekes/ecology/
euglena.htm
!  http://www.chemspider.com/Chemical-Structure.
1086.html
!  Mark
Krotec, PTEI
Anova: Single Factor
SUMMARY
Groups Count Sum Average Variance
1 7 1.313 0.187571 6.7E-05
2 7 1.803 0.257571 0.000119
3 7 1.523 0.217571 0.000237
4 7 1.339 0.191286 8.36E-05
5 7 1.26 0.18 9.87E-05
ANOVA
Source of Variation SS df MS F P-value F crit
Between Groups 0.028157 4 0.007039 58.16652
1.05E-13 2.689628
Within Groups 0.003631 30 0.000121
Total 0.031788 34 Anova: Single Factor
SUMMARY
Groups Count Sum
Average
Variance
1 7 1.313 0.187571 6.7E-05
2 7 1.803 0.257571 0.000119
3 7 1.523 0.217571 0.000237
4 7 1.339 0.191286 8.36E-05
5 7 1.26 0.18 9.87E-05
ANOVA
Source of Variation SS df MS F P-value
F crit
Between Groups 0.028157 4 0.007039
58.16652 1.05E-13 2.689628
Within Groups 0.003631 30 0.000121
Total 0.031788 34
Anova: Single Factor
SUMMARY
Groups Count Sum
Average
Variance
1 7 1.176 0.168 0.000108
2 7 1.739 0.248429 0.000386
3 7 1.34 0.191429 0.000301
4 7 1.107 0.158143 7.35E-05
5 7 1.057 0.151 0.000108
ANOVA
Source of Variation SS df MS F P-value
F crit
Between Groups 0.043526 4 0.010882
55.70477 1.85E-13 2.689628
Within Groups 0.00586 30 0.000195
Total 0.049386 34
Anova: Single Factor
SUMMARY
Groups Count Sum
2
3
4
5
Average
Variance
7 2.093 0.299 6.97E-05
7 1.162 0.166 0.000938
7 1.049 0.149857 0.000167
7 0.913 0.130429 7.86E-05
0 0 #DIV/0! #DIV/0!
ANOVA
Source of Variation SS df MS F P-value
F crit
Between Groups 0.122942 4 0.030735
93.99736 6.64E-14 2.795539
Within Groups 0.007521 23 0.000327
Total 0.130462 27