viii
Preface to the Second Edition
laboratory analyses. However, some options can be performed completely in the
classroom laboratory. Although we consider these options to be the least desirable,
some topics are more appropriately conducted in the laboratory at this level of
instruction. For example, the important and complex subject of hydrodynamics can
be introduced in a most illuminating and enjoyable manner by means of lake model
experiments.
We have expanded the questions at the end of each exercise. We encourage students
to answer as many of them as possible, for they often generate critical evaluations
of the problems being addressed and the efficacy of the techniques being used. The
questions and references provided for each exercise can lead students to explore
further the myriad complexities of freshwater ecosystems.
The taxonomy of dominant aquatic flora and fauna is consistently a source of
frustration both in the teaching of courses in limnology and in the preparation of this
book. The taxonomic backgrounds and experience of students entering an initial
course in limnology are usually diverse. Even superficial keys to common organisms
from bacteria to fish would exceed the length of the present text. In the first edition,
we included a few basic keys to orient students with little taxonomical experience to
major separations. These keys were not received well by systematists and were not
used extensively by students. Therefore, we include only a few rudimentary "starter"
taxonomic keys in this edition, and we recommend that the instructors use general
and regional guides to the taxonomy of the flora and fauna of particular regions. We
cite example references of useful general taxonomic works.
We recognize that it would be difficult to accomplish all of the exercises in this
book in an intensive course in limnology during a single semester. Hopefully our
efforts, however, will assist in reducing the labors in such courses and enhance insights
into the operational integrity of aquatic ecosystems. We found the experiences of
others important to the improvements to this book. We welcome further suggestions
on how the exercises might be improved or expanded.
Our ideas for effective instruction of certain topics had a long and diffuse
developmental history. As a result, we are no longer certain of their exact origins.
Effective teachers in our background certainly contributed at least indirectly to aspects
that appear in some exercises, particularly A.D. Hasler, W.T. Edmondson, G.H. Lauff,
D.C. Chandler, and J.R. Vallentyne. Gordon L. Godshalk read critically the entire
work and offered many helpful suggestions to both the first edition and parts of the
second edition. Constructive criticism and good counsel have been received from
numerous persons, including students as they grappled with the techniques in classes.
Discussions about and suggested revisions to portions of the first and/or second
editions were provided by H.L. Allen, J.R. Barnes, R. Bilby, J. Cole, W.G. Crumpton,
H.W. Cunningham, F. deNoyelles, J.A. Dickerman, J. Eaton, R. Edwards, P. Godfrey,
J.B. Grace, C.A.S. Hall, D.J. Hall, R. Hall, G. Hendrey, M. Mattson, W. McDowell,
J. Meyer, S. Nodvin, D.K. Nordstrom, P.H. Rich, B. Riemann, D.W. Schindler,
J. Sloane, A. Stewart, D. Strayer, R. Walter, A.K. Ward, G.M. Ward, and W. Youngs, Jr.
Special insights were received on specific topics by several individuals, particularly
toward improvements in the second edition. Arthur C. Benke offered great refinements
and improvements to the treatments of benthos. Michael F. Coveney, Clifford Ochs,
and Michael Pace counseled us on our new treatment of bacterial productivity. The
new exercise on predator-prey analyses was guided by the efforts of Kenneth Wagner
and W. Charles Kerfoot. Mark D. Mattson contributed significantly to the revision
of the exercise on the inorganic carbon complex. The exercises on manipulation of
model ecosystems, diurnal changes in stream ecosystems, and effect of sewage outfall
Preface to the Second Edition
laboratory analyses. However, some options can be performed completely in the
classroom laboratory. Although we consider these options to be the least desirable,
some topics are more appropriately conducted in the laboratory at this level of
instruction. For example, the important and complex subject of hydrodynamics can
be introduced in a most illuminating and enjoyable manner by means of lake model
experiments.
We have expanded the questions at the end of each exercise. We encourage students
to answer as many of them as possible, for they often generate critical evaluations
of the problems being addressed and the efficacy of the techniques being used. The
questions and references provided for each exercise can lead students to explore
further the myriad complexities of freshwater ecosystems.
The taxonomy of dominant aquatic flora and fauna is consistently a source of
frustration both in the teaching of courses in limnology and in the preparation of this
book. The taxonomic backgrounds and experience of students entering an initial
course in limnology are usually diverse. Even superficial keys to common organisms
from bacteria to fish would exceed the length of the present text. In the first edition,
we included a few basic keys to orient students with little taxonomical experience to
major separations. These keys were not received well by systematists and were not
used extensively by students. Therefore, we include only a few rudimentary "starter"
taxonomic keys in this edition, and we recommend that the instructors use general
and regional guides to the taxonomy of the flora and fauna of particular regions. We
cite example references of useful general taxonomic works.
We recognize that it would be difficult to accomplish all of the exercises in this
book in an intensive course in limnology during a single semester. Hopefully our
efforts, however, will assist in reducing the labors in such courses and enhance insights
into the operational integrity of aquatic ecosystems. We found the experiences of
others important to the improvements to this book. We welcome further suggestions
on how the exercises might be improved or expanded.
Our ideas for effective instruction of certain topics had a long and diffuse
developmental history. As a result, we are no longer certain of their exact origins.
Effective teachers in our background certainly contributed at least indirectly to aspects
that appear in some exercises, particularly A.D. Hasler, W.T. Edmondson, G.H. Lauff,
D.C. Chandler, and J.R. Vallentyne. Gordon L. Godshalk read critically the entire
work and offered many helpful suggestions to both the first edition and parts of the
second edition. Constructive criticism and good counsel have been received from
numerous persons, including students as they grappled with the techniques in classes.
Discussions about and suggested revisions to portions of the first and/or second
editions were provided by H.L. Allen, J.R. Barnes, R. Bilby, J. Cole, W.G. Crumpton,
H.W. Cunningham, F. deNoyelles, J.A. Dickerman, J. Eaton, R. Edwards, P. Godfrey,
J.B. Grace, C.A.S. Hall, D.J. Hall, R. Hall, G. Hendrey, M. Mattson, W. McDowell,
J. Meyer, S. Nodvin, D.K. Nordstrom, P.H. Rich, B. Riemann, D.W. Schindler,
J. Sloane, A. Stewart, D. Strayer, R. Walter, A.K. Ward, G.M. Ward, and W. Youngs, Jr.
Special insights were received on specific topics by several individuals, particularly
toward improvements in the second edition. Arthur C. Benke offered great refinements
and improvements to the treatments of benthos. Michael F. Coveney, Clifford Ochs,
and Michael Pace counseled us on our new treatment of bacterial productivity. The
new exercise on predator-prey analyses was guided by the efforts of Kenneth Wagner
and W. Charles Kerfoot. Mark D. Mattson contributed significantly to the revision
of the exercise on the inorganic carbon complex. The exercises on manipulation of
model ecosystems, diurnal changes in stream ecosystems, and effect of sewage outfall