Foreword
xv
reader will find that several important changes are
recommended here; and in some cases a species or
even a genus (Heterozostera) has disappeared (and at
higher levels important changes are recommended).
These changes have not at this time been accepted
by many taxonomists. This is reflected in the stance
of Chapter 1 (den Hartog and Kuo). It will be many
years before many of these differences are resolved.
As both approaches have their shortcomings, there
has been no attempt in this book to be prescriptive:
where differences do occur the reader is advised of
the different approaches and is left to make up her/his
mind on the subject.
Seagrasses are, par excellence, the plants that
evolved hydrophilous pollination but only recently
has a mechanistic approach been undertaken. Ackerman (Chapter 4) reviews the nature of pollination mechanisms and the unique adaptations these
plants have evolved to insure successful pollination. And with successful pollination emerges the
production of a seed, the unifying theme in all angiosperm species. Yet little is known about seeds,
seed ecology and seed dispersal processes in seagrasses. Orth et al., (Chapter 5) review the scant
but growing body of literature for seagrasses but
more importantly, attempt to integrate emerging issues in the terrestrial realm and their applicability
to seagrasses.
Seagrasses influence numerous processes and
these are highlighted in a number of excellent chapters. Marba et al. (Chapter 6) review the role of
seagrass beds on coastal biogeochemistry, by first
examining their effect on particulate and dissolved
materials (i.e. organic matter, dissolved inorganic
carbon, carbonates, gases) in the water column and
sediments of coastal areas, and (2) by examining the
processes involved in mineralization of organic matter and nutrient cycling in sediments colonised by
seagrasses. Mateo et al. (Chapter 7) describe carbon
fluxes in seagrass ecosystems. Koch et al. (Chapter
8) examine hydrodynamics at scales ranging from
molecules to ecosystems. Romero et al. (Chapter 9)
highlight nutrient dynamics. Borum et al. (Chapter
10) review current status of knowledge with respect
to oxygen production, consumption and transport
within seagrasses, and briefly discuss the potential
coupling between seagrass oxygen dynamics and the
occurrence of die-off events in seagrass beds. And
finally, Duarte et al. (Chapter 11) address processes
and mechanisms responsible for the dynamics of seagrass meadows.
Light and photosynthesis and their measurement
are dominant themes from the earliest papers in seagrass ecology. Yet this field has been rapidly evolving
with the development of new tools leading to new
discoveries about light and its measurement and the
basis of light capture and the photosynthetic mechanisms. A series of chapters allow for the reader to
follow in progression the science of light penetration into marine waters (Zimmerman and Dekker,
Chapter 12), the influence of seagrasses on light absorption and light refection in shallow communities
(Zimmerman, Chapter 13), the emerging role of remote sensing in seagrasses (Dekker et al., Chapter
15), and finally the importance of photosynthesis
and the photosynthetic mechanisms of seagrasses
(Larkum et al., Chapter 14).
Faunal and floral studies were also an important
component in the early work by Japanese, American
and European scientists and coincided with the many
attempts to define community. This was followed by
experimental work on the important interactions between plants and the many animals reported from
seagrass beds. Borowitza et al. (Chapter 19) review
the literature on epiphyte diversity and abundance.
Valentine and Duffy (Chapter 20) provide an important synthesis of the grazing world, both macro
and meso-grazers, and their important direct and indirect interactions at varying spatial scales. Gillanders (Chapter 21) explores the latest developments in
fisheries utilization, including new techniques for assessing habitat linkages (e.g. otolith chemistry) and
how important seagrass beds are to fish production.
Finally Heck and Orth (Chapter 22) succinctly summarize the previous generalizations that continue to
be supported by recent work, and then focus attention on results that challenge the conventional
wisdom on predator-prey interactions in seagrass
meadows.
Research in the 1970’s in Europe, United States
and Australia showed the devastating negative influence of anthropogenic factors on seagrass distribution and abundance. Loss of seagrasses has continued at an alarming pace as human habitation of the
coastal zone rapidly expands. Walker et al. (Chapter
23) detail aspects of more recent research demonstrating changes, both negative and positive, in seagrass distributions, as revealed by mapping and other
detailed investigations. Ralph et al. (Chapter 24) provide an overview of the current understanding of how
anthropogenic contaminants impact seagrasses, the
ecophysiological responses of seagrasses and finally
xv
reader will find that several important changes are
recommended here; and in some cases a species or
even a genus (Heterozostera) has disappeared (and at
higher levels important changes are recommended).
These changes have not at this time been accepted
by many taxonomists. This is reflected in the stance
of Chapter 1 (den Hartog and Kuo). It will be many
years before many of these differences are resolved.
As both approaches have their shortcomings, there
has been no attempt in this book to be prescriptive:
where differences do occur the reader is advised of
the different approaches and is left to make up her/his
mind on the subject.
Seagrasses are, par excellence, the plants that
evolved hydrophilous pollination but only recently
has a mechanistic approach been undertaken. Ackerman (Chapter 4) reviews the nature of pollination mechanisms and the unique adaptations these
plants have evolved to insure successful pollination. And with successful pollination emerges the
production of a seed, the unifying theme in all angiosperm species. Yet little is known about seeds,
seed ecology and seed dispersal processes in seagrasses. Orth et al., (Chapter 5) review the scant
but growing body of literature for seagrasses but
more importantly, attempt to integrate emerging issues in the terrestrial realm and their applicability
to seagrasses.
Seagrasses influence numerous processes and
these are highlighted in a number of excellent chapters. Marba et al. (Chapter 6) review the role of
seagrass beds on coastal biogeochemistry, by first
examining their effect on particulate and dissolved
materials (i.e. organic matter, dissolved inorganic
carbon, carbonates, gases) in the water column and
sediments of coastal areas, and (2) by examining the
processes involved in mineralization of organic matter and nutrient cycling in sediments colonised by
seagrasses. Mateo et al. (Chapter 7) describe carbon
fluxes in seagrass ecosystems. Koch et al. (Chapter
8) examine hydrodynamics at scales ranging from
molecules to ecosystems. Romero et al. (Chapter 9)
highlight nutrient dynamics. Borum et al. (Chapter
10) review current status of knowledge with respect
to oxygen production, consumption and transport
within seagrasses, and briefly discuss the potential
coupling between seagrass oxygen dynamics and the
occurrence of die-off events in seagrass beds. And
finally, Duarte et al. (Chapter 11) address processes
and mechanisms responsible for the dynamics of seagrass meadows.
Light and photosynthesis and their measurement
are dominant themes from the earliest papers in seagrass ecology. Yet this field has been rapidly evolving
with the development of new tools leading to new
discoveries about light and its measurement and the
basis of light capture and the photosynthetic mechanisms. A series of chapters allow for the reader to
follow in progression the science of light penetration into marine waters (Zimmerman and Dekker,
Chapter 12), the influence of seagrasses on light absorption and light refection in shallow communities
(Zimmerman, Chapter 13), the emerging role of remote sensing in seagrasses (Dekker et al., Chapter
15), and finally the importance of photosynthesis
and the photosynthetic mechanisms of seagrasses
(Larkum et al., Chapter 14).
Faunal and floral studies were also an important
component in the early work by Japanese, American
and European scientists and coincided with the many
attempts to define community. This was followed by
experimental work on the important interactions between plants and the many animals reported from
seagrass beds. Borowitza et al. (Chapter 19) review
the literature on epiphyte diversity and abundance.
Valentine and Duffy (Chapter 20) provide an important synthesis of the grazing world, both macro
and meso-grazers, and their important direct and indirect interactions at varying spatial scales. Gillanders (Chapter 21) explores the latest developments in
fisheries utilization, including new techniques for assessing habitat linkages (e.g. otolith chemistry) and
how important seagrass beds are to fish production.
Finally Heck and Orth (Chapter 22) succinctly summarize the previous generalizations that continue to
be supported by recent work, and then focus attention on results that challenge the conventional
wisdom on predator-prey interactions in seagrass
meadows.
Research in the 1970’s in Europe, United States
and Australia showed the devastating negative influence of anthropogenic factors on seagrass distribution and abundance. Loss of seagrasses has continued at an alarming pace as human habitation of the
coastal zone rapidly expands. Walker et al. (Chapter
23) detail aspects of more recent research demonstrating changes, both negative and positive, in seagrass distributions, as revealed by mapping and other
detailed investigations. Ralph et al. (Chapter 24) provide an overview of the current understanding of how
anthropogenic contaminants impact seagrasses, the
ecophysiological responses of seagrasses and finally