The Ecology of Aerial Algae

182 Pages·2012·2.16 MB·English

by  Jennifer Ann Ress

THE ECOLOGY OF AERIAL ALGAE

Jennifer A. Ress

A Dissertation

Submitted to the Graduate College of Bowling Green
State University in partial fulfillment of
the requirements for the degree of

DOCTOR OF PHILOSOPHY
May 2012
Committee:
Rex L. Lowe, Advisor
John T. Chen
Graduate Faculty Representative
George S. Bullerjahn
Jeffrey R. Johansen
Daniel M. Pavuk
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ABSTRACT

Rex Lowe, Advisor

The ecology and adaptations of aerial algal communities from selected areas in North
America were examined. First, morphological adaptations to desiccation as well as microhabitat
preference of diatoms were explored from the Great Smoky Mountains National Park (GSMNP).
Reduced size as an adaptation against desiccation was not supported by the data, with aerial
diatoms being longer than had been previously shown in the literature. However, a reduction in
the amount of open area on the valve face as an adaptation against desiccation was supported by
the data. Second, aerial algal communities from the GSMNP and the Lake Superior region were
compared and contrasted. Factors structuring algal communities in each region were examined
and similarities and differences were identified between the two regions. These regions were not
found to support unique aerial algal communities. Third, bryophyte-algal associations were
investigated from a cliff face in O’ahu, HI. Algal species were examined for fidelity to
bryophyte species within this site. There was no relationship found between algal species and
bryophyte species, however, there was a relationship between algal species and both aspect and
light levels. Finally, desiccation tolerance of algal communities was studied through a laboratory
experiment. Changes in algal community composition were examined after exposure to different
periods of desiccation. Overall, algal community composition was not found to change as a
result of exposure to different periods of desiccation. This dissertation explored algal
communities from understudied aerial and explored factors that structure and influence
community composition.
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DEDICATION

To my son, Alexander,

I am so excited to watch you and be there with you as you begin your own exploration
of the world.
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ACKNOWLEDGMENTS
First and foremost, I want to thank my husband, Evan Thomas, for his constant support
and encouragement throughout this project. Not only did Evan provide much needed emotional
support, but he also provided logistical support throughout the project. Evan was always ready
to help me brainstorm, aid in fieldwork, and review my manuscripts time and time again. I also
thank him for setting aside work on his own dissertation during the last year of my program to
allow me more time to complete my work. Without his support and self-sacrifice, I would not
have been able to complete this work. I also want to thank my parents, Robert and Judith Ress,
for their support and encouragement throughout this process.
I want to thank my advisor, Dr. Rex Lowe, for his guidance and support throughout my
graduate career. I want to thank Rex for allowing me the independence to pursue and coordinate
this project. Rex has helped me grow and develop as a researcher which has allowed me to
become a more knowledgeable and confident scientist. I would also like to thanks my
committee, Dr. George Bullerjahn, Dr. Jeff Johansen, Dr. Dan Pavuk, and Dr. John Chen, for
their guidance and time.
This work was funded in part by a Sigma Xi Grant-in-Aid of research.
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TABLE OF CONTENTS
Page
INTRODUCTION: ALGAL COMMUNITIES FROM AERIAL HABITATS .................... 1
CHAPTER I. MORPHOLOGICAL ADAPTATIONS AND HABITAT PREFERENCE OF
AERIAL DIATOMS
Introduction.... ............................................................................................................ 6
Study Area........ ......................................................................................................... 8
Methods...................................................................................................................... 8
Results............ ............................................................................................................ 10
Cell Length..................................................................................................... 11
Biovolumes .................................................................................................... 12
Proportion Of Areolar Area ........................................................................... 13
Microhabitat Preference ................................................................................. 14
Discussion ...................................................................................................... 15
CHAPTER II. CONTRAST AND COMPARISON OF AERIAL ALGAL COMMUNITIES
FROM TWO DISTINCT REGIONS
Introduction.............. .................................................................................................. 19
Study Area...... ........................................................................................................... 20
Methods...................................................................................................................... 22
Results ........................................................................................................................ 23
Discussion............... ................................................................................................... 26
CHAPTER III. BRYOPHYTES AND ASSOCIATED ALGAL COMMUNITIES FROM AN
EXPOSED CLIFF FACE ON O'AHU (HAWAI’I, USA)
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Introduction............. ................................................................................................... 30
Study Area........... ...................................................................................................... 31
Methods...................................................................................................................... 32
Results ........................................................................................................................ 33
Discussion................ .................................................................................................. 35
CHAPTER IV. DESICCATION TOLERANCE OF AQUATIC AND PSEUDOAERIAL
ALGAE
Introduction........... ..................................................................................................... 39
Study Area........ ......................................................................................................... 40
Methods...................................................................................................................... 41
Results..................... ................................................................................................... 43
Cell Density Data ........................................................................................... 43
Site 1 .................................................................................................. 45
Site 3 .................................................................................................. 45
Site 5 .................................................................................................. 46
Community Composition Data ...................................................................... 47
Site 1 .................................................................................................. 47
Site 3 .................................................................................................. 48
Site 5 .................................................................................................. 48
Non-Metric Multidimensional Scaling .......................................................... 49
Site 1 .................................................................................................. 49
Site 3 .................................................................................................. 49
Site 5 .................................................................................................. 50
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Discussion................... ............................................................................................... 50
CONCLUSIONS AND FUTURE DIRECTIONS…............................................................. 54
LITERATURE CITED .......................................................................................................... 57
TABLES......................... ....................................................................................................... 64
CHAPTER I....... ........................................................................................................ 64
CHAPTER II... ........................................................................................................... 91
CHAPTER III. ........................................................................................................... 115
CHAPTER IV. ........................................................................................................... 122
FIGURES................... ........................................................................................................... 135
CHAPTER II... ........................................................................................................... 135
CHAPTER III. ........................................................................................................... 144
CHAPTER IV. ........................................................................................................... 154
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LIST OF TABLES
Table Page
CHAPTER I:
1 Site information for aerial and aquatic samples collected from the Great Smoky
Mountains National Park including site identification number, location, habitat
type, microhabitat type, pH, GPS coordinates, light level (µmols-1 m-2 per µA) (*
indicates average value of light levels measured at different times of day), aspect,
sponge weight change (g), and moisture category; Light, aspect, sponge weight
change and moisture category were recorded only from aerial habitats. ................... 65
2 Aerial taxa with the highest relative abundances with the range in length measured
for each taxon ............................................................................................................. 71
3 Taxa occurring with >1% relative abundance in populations from aerial habitats
with differing moisture availabilities (1=dry, 2=damp, 3=wet, 4=very wet). ........... 72
4 Aquatic taxa with the highest relative abundances with the range in length measured
for each taxon. ............................................................................................................ 74
5 Median, maximum, and minimum lengths of diatom communities from both aerial
and aquatic populations; * indicates significance ...................................................... 75
6 Median lengths of taxa shared between aerial and aquatic habitats, and median
lengths of taxa unique to aerial and aquatic habitats; * indicates significance .......... 76
7 Median lengths for taxa present in both aerial and aquatic habitats; * indicates
significance……. ....................................................................................................... 77
8 Median, maximum, and minimum cell lengths of diatoms from aerial habitats with
different moisture availabilities (1=dry, 2=damp, 3=wet, 4=very wet) ..................... 78
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9 Pairwise Wilcoxon rank sum tests of cell length between diatom populations from
different moisture categories; * indicates significance (Bonferroni correction factor
α = 0.0125 used for pairwise comparisons) ............................................................... 79
10 Median lengths in each moisture category (1=dry, 2=damp, 3=wet, 4=very wet) for
taxa with the highest relative abundances in the aerial habitats; Kruskal-Wallis
nonparametric analysis of variance result with post hoc pairwise Wilcoxon rank sum
tests for taxa occurring in three or more moisture categories, Wilcoxon rank sum
test for taxa occurring in only two moisture categories; * indicates significance
(Bonferroni correction factor α = 0.0167used for post hoc pairwise comparisons).... 80
11 Median, maximum, and minimum biovolumes for both aerial and aquatic
populations; * indicates significance ......................................................................... 81
12 Median biovolumes of taxa shared between aerial and aquatic habitats, and
median biovolumes of taxa unique to aerial and aquatic habitats; * indicates
significance………… ................................................................................................ 82
13 Median biovolumes for taxa present in both aerial and aquatic habitats; * indicates
significance…. ........................................................................................................... 83
14 Median, maximum, and minimum biovolumes of diatoms from aerial habitats with
different moisture availabilities (1=dry, 2=damp, 3=wet, 4=very wet) ..................... 84
15 Pairwise Wilcoxon rank sum tests of biovolume between different moisture
categories; * indicates significance (Bonferroni correction factor α = 0.0125 used
for pairwise comparisons) .......................................................................................... 85
16 Median biovolumes in each moisture category (1=dry, 2=damp, 3=wet, 4=very
wet) for taxa with the highest relative abundances in the aerial habitats; Kruskal-
x
Wallis nonparametric analysis of variance result with post hoc pairwise Wilcoxon
rank sum tests for taxa occurring in three or more moisture categories, Wilcoxon
rank sum test for taxa occurring in only two moisture categories; * indicates
significance (Bonferroni correction factor α = 0.0167used for post hoc pairwise
comparisons) ............................................................................................................ 86
17 Median percent open area of diatoms from aerial habitats with different moisture
availabilities (1=dry, 2=damp, 3=wet, 4=very wet)................................................... 87
18 Pairwise Wilcoxon rank sum tests of percent open area between different moisture
categories; * indicates significance (Bonferroni correction factor α = 0.0125 used for
pairwise comparisons) ............................................................................................... 88
19 List of common species frequently encountered in bryophytic samples. A species was
considered common if it occurred in >20% of the samples ....................................... 89
20 List of common species frequently encountered in epilithic samples. A species was
considered common if it occurred in >20% of the samples ....................................... 90
CHAPTER II:
1 Taxa list for the two regions Lake Superior (LSR) and Great Smoky Mountains
National Park (GSMNP); an “X” indicates presence of taxon in region ................... 92
2 List of common taxa frequently encountered across Lake Superior region samples.
A taxon was considered common if it occurred in >20% of the samples .................. 102
3 Taxa occurring with >1% relative abundance in populations from aerial habitats
with differing moisture availabilities (1=dry, 2=damp, 3=wet, 4=very wet). ........... 103
4 Aquatic taxa with the highest relative abundances with the range in length measured
for each taxon. ............................................................................................................ 104