understanding arsenic hyperaccumulation by pteris vittata l

171 Pages·2005·1.47 MB·English

ARSENIC HYPERACCUMULATION BY Pteris vittata L. AND ITS POTENTIAL
FOR PHYTOREMEDIATION OF ARSENIC-CONTAMINATED SOILS

By

GINA MARIE KERTULIS-TARTAR

A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL
OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT
OF THE REQUIREMENTS FOR THE DEGREE OF
DOCTOR OF PHILOSOPHY

UNIVERSITY OF FLORIDA

2005
Copyright 2005

by

Gina Marie Kertulis-Tartar
This work is dedicated to my wonderful husband, Kenneth Tartar, for his unending love,
patience and encouragement.
ACKNOWLEDGMENTS
I wish to thank my advisor and mentor, Dr. Lena Q. Ma, for her invaluable advice,
guidance, critiques and devotion. I am grateful that she always expressed genuine
interest in my future, as well as in me as a student, a scientist and a person. I am also
grateful to my committee members, Drs. Nicholas Comerford, Charles Guy, Gregory
MacDonald and Joseph Vu, who provided valuable assistance and advice to ensure the
quality of my research. I also wish to sincerely thank Dr. Bala Rathinasabapathi, who
graciously spent countless hours advising me in plant physiology and biochemistry.
Much of the data collected and presented would not have been possible without the
assistance of Mr. Thomas Luongo. I am grateful not only for his analytical assistance but
also for his invaluable friendship and advice. I wish to thank Dr. Tait Chirenje, who
provided experimental and statistical advice as well as friendship. I am grateful to Ms.
Heather Williams for her much needed assistance in harvesting ferns and soil sampling. I
also wish to thank the past and present members of the Biogeochemistry of Trace Metals
Laboratory, Maria Silva, Donald Hardison, Joonki Yoon, Abioye Fayiga, Drs. Jorge
Santos, Mrittunjai Srivastava, Nandita Singh, Rocky Cao, Chip Appel, Bhaskar Bondada,
Mike Tu, Carmen Rivero and Ju-Sik Cho, for all that they have taught me.
I am eternally grateful to my parents, Anthony and Barbara Kertulis, for their
unending love and support and for their constant encouragement of every one of my
endeavors. All that I am and all that I have accomplished is truly a result of their
iv
dedication and commitment. I also wish to thank my mother-in-law, Margaret Tartar, for
her continuous words of encouragement and praise.
I would not have completed this work without the support, love and patience of my
husband, Kenneth Tartar. I am thankful for his unrelenting encouragement and
dedication, despite the countless sacrifices he made in order for me to complete my Ph.D.
I am truly thankful that God has blessed me by putting him in my life. I lovingly
dedicate this study to him.

v
TABLE OF CONTENTS

page
ACKNOWLEDGMENTS.................................................................................................iv
LIST OF TABLES...............................................................................................................x
LIST OF FIGURES..........................................................................................................xii
ABSTRACT.....................................................................................................................xiv
CHAPTER
1 INTRODUCTION........................................................................................................1
2 LITERATURE REVIEW.............................................................................................4
Arsenic..........................................................................................................................4
Chemistry of Arsenic.............................................................................................4
Toxicity of Arsenic................................................................................................5
Arsenic in the Atmosphere....................................................................................6
Arsenic in Minerals...............................................................................................8
Arsenic in Water....................................................................................................8
Arsenic in Soils...........................................................................................................10
Behavior of Arsenic.............................................................................................10
Arsenic Availability.............................................................................................10
Arsenic Speciation...............................................................................................13
Arsenic Contamination...............................................................................................14
Pesticides.............................................................................................................14
Mining and Smelting...........................................................................................16
Combustion of Fossil Fuels.................................................................................17
Biosolids..............................................................................................................17
Remediation of Arsenic Contaminated Soils..............................................................18
Physical Remediation..........................................................................................18
Chemical Remediation........................................................................................20
Bioremediation....................................................................................................20
Phytoremediation........................................................................................................21
Phytoextraction....................................................................................................22
Hyperaccumulators..............................................................................................23
Pteris vittata L..............................................................................................24
Other Arsenic Hyperaccumulating Ferns.....................................................26
vi
Arsenic in Plants.........................................................................................................27
Arsenic Uptake by Plants....................................................................................28
Antioxidants and Antioxidant Enzymes..............................................................28
Phytochelatins......................................................................................................32
3 ARSENIC SPECIATION AND TRANSPORT IN Pteris vittata L..........................34
Introduction.................................................................................................................34
Materials and Methods...............................................................................................36
Experimental Setup.............................................................................................36
Xylem Sap Extraction..........................................................................................37
Chemical Analysis of Arsenic and Phosphorus...................................................37
Arsenic Speciation in Plant and Xylem Sap Samples.........................................37
Experimental Design and Statistical Analysis.....................................................40
Results.........................................................................................................................40
Arsenic Concentration and Speciation in Roots and Fronds...............................40
Arsenic Concentration and Speciation in Xylem Sap.........................................42
Phosphorus Concentration in Xylem Sap............................................................44
Discussion...................................................................................................................47
4 EFFECTS OF ARSENIC ON GLUTATHIONE REDUCTASE AND
CATALASE IN THE FRONDS OF Pteris vittata L.................................................53
Introduction.................................................................................................................53
Materials and Methods...............................................................................................55
Plant and Chemical Materials..............................................................................55
Enzyme Extraction..............................................................................................56
Protein and Enzymatic Activity Determinations.................................................56
Enzyme Induction Study.....................................................................................57
Determination of Apparent Kinetics...................................................................58
Determination of Arsenic Effects on Enzyme Activities....................................59
Results.........................................................................................................................59
Glutathione Reductase and Catalase Induction Study.........................................59
Glutathione Reductase and Catalase Apparent Kinetics.....................................61
Effect of Arsenic on Enzyme Activities..............................................................68
Discussion...................................................................................................................72
5 PHYTOREMEDIATION OF AN ARSENIC-CONTAMINATED SITE USING
Pteris vittata L............................................................................................................76
Introduction.................................................................................................................76
Materials and Methods...............................................................................................78
Experimental Site................................................................................................78
Planting and Plot Maintenance............................................................................79
Plot 1............................................................................................................79
Plot 2............................................................................................................79
Plant Harvests......................................................................................................80
vii
Plot 1............................................................................................................80
Plot 2............................................................................................................82
Determination of Frond Biomass and Arsenic Concentrations...........................83
Soil Sampling......................................................................................................83
Plot 1............................................................................................................83
Plot 2............................................................................................................84
Determination of Total Soil Arsenic...................................................................84
Sequential Soil Arsenic Fractionation.................................................................84
Bioconcentration Factor......................................................................................86
Statistical Analysis..............................................................................................87
Results.........................................................................................................................87
Arsenic Removal by Ferns..................................................................................87
Plot 1............................................................................................................87
Plot 2............................................................................................................90
Soil Arsenic Concentrations................................................................................91
Plot 1............................................................................................................91
Plot 2............................................................................................................92
Sequential Soil Arsenic Fractionation.................................................................95
Mass balance of Arsenic......................................................................................97
Plot 1............................................................................................................97
Plot 2............................................................................................................97
Bioconcentration Factor......................................................................................98
Discussion...................................................................................................................98
Plant Arsenic Removal........................................................................................99
Soil Arsenic Concentrations..............................................................................103
Sequential Arsenic Fractionation......................................................................105
Mass Balance.....................................................................................................107
Estimated Time of Remediation........................................................................113
Estimated Remediation Cost.............................................................................115
Suggested Phytoextraction Setup......................................................................117
6 EFFECT OF Pteris vittata L. ON ARSENIC LEACHING AND ITS
POTENTIAL FOR THE DEVELOPMENT OF A NOVEL
PHYTOREMEDIATION METHOD.......................................................................119
Introduction...............................................................................................................119
Materials and Methods.............................................................................................121
Overview of Proposed Phytoleaching System..................................................121
Soil.....................................................................................................................122
Treatments.........................................................................................................122
Fern, Soil and Leachate Analyses.....................................................................124
Experimental Design and Statistical Analysis...................................................125
Results.......................................................................................................................125
Leachate.............................................................................................................125
Ferns..................................................................................................................127
Soil.....................................................................................................................129
Discussion.................................................................................................................130
viii
Future Directions......................................................................................................135
7 CONCLUSIONS......................................................................................................138
LIST OF REFERENCES.................................................................................................142
BIOGRAPHICAL SKETCH...........................................................................................156

ix
LIST OF TABLES
Table page

2-1 Summary of select current remediation technologies for arsenic-contaminated soil..19
3-1 Total arsenic concentrations in xylem sap of P. vittata exposed to 0, 10 or 50 mg l-
1 arsenic....................................................................................................................43
4-1 Summary of apparent kinetic parameters for GR and CAT........................................68
5-1 A comparison of the total biomass removed, average frond arsenic concentration
and amount of arsenic remediated from the senescing frond harvests in 2001 and
(DD1) in 2002..........................................................................................................88
5-2 Comparison of average frond arsenic concentrations, total amount of biomass
removed and amount of arsenic removed between the senescing fern fronds
harvested in 2001 and 2002 (DD1), and all fronds harvested in December 2001
and August 2002 (A2x)............................................................................................89
5-3 Comparison of the total amount of biomass removed between the fronds harvested
in 2003 and 2004......................................................................................................91
5-4 Comparison of the average frond arsenic concentrations and amount of arsenic
removed between the fronds harvested in 2003 and 2004.......................................91
5-5 Average soil arsenic concentrations and arsenic depletion of soil samples taken in
plot 1 in 2000, 2001 and 2002..................................................................................92
5-6 Average soil arsenic concentrations and net arsenic depletion of soil samples taken
inside plot 2 in 2002, 2003 and 2004.......................................................................93
5-7 Average soil arsenic concentrations and net arsenic depletion of soil samples taken
outside plot 2 in 2002, 2003 and 2004.....................................................................93
5-8 Calculated mass balance of arsenic in the soil-plant system of plot 1 from 2000 to
2002..........................................................................................................................97
5-9 Calculated mass balance of arsenic in the soil-plant system of plot 2 from 2002 to
2004..........................................................................................................................98
5-10 Estimated time for phytoextraction of plot 2 with P. vittata...................................115
x