Table Of ContentHubbard Brook
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Hubbard Brook
(cid:495)(cid:483)(cid:480)(cid:3)(cid:494)(cid:495)(cid:490)(cid:493)(cid:500)(cid:3)(cid:490)(cid:481)(cid:3)(cid:476)(cid:3)(cid:481)(cid:490)(cid:493)(cid:480)(cid:494)(cid:495)(cid:3)(cid:480)(cid:478)(cid:490)(cid:494)(cid:500)(cid:494)(cid:495)(cid:480)(cid:488)
NEW HAVEN AND LONDON
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Printed in China.
ISBN 978- 0- 300- 20364- 6 (cloth : alk. paper)
Library of Congress Control Number: 2015948837
A catalogue record for this book is available from the British Library.
Copyright © 2016 by Richard T. Holmes and Gene E. Likens.
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Preface vii
Acknowledgments ix
Timeline: From the Glaciers to the Present xi
Prologue: Step into the Forest—Today (cid:506)
(cid:491)(cid:476)(cid:493)(cid:495)(cid:3)(cid:635)(cid:17)(cid:3)(cid:495)(cid:483)(cid:480)(cid:3)(cid:481)(cid:490)(cid:493)(cid:480)(cid:494)(cid:495)(cid:3)(cid:480)(cid:478)(cid:490)(cid:494)(cid:500)(cid:494)(cid:495)(cid:480)(cid:488)(cid:3)(cid:476)(cid:494)(cid:3)(cid:476)(cid:3)(cid:487)(cid:476)(cid:477)(cid:490)(cid:493)(cid:476)(cid:495)(cid:490)(cid:493)(cid:500)
(cid:506) Ecosystem and Ecological Studies at Hubbard Brook (cid:514)
(cid:507) The Small Watershed- Ecosystem Approach (cid:506)(cid:512)
(cid:478)(cid:490)(cid:489)(cid:495)(cid:480)(cid:489)(cid:495)(cid:494)
(cid:491)(cid:476)(cid:493)(cid:495)(cid:3)(cid:636)(cid:17)(cid:3)(cid:478)(cid:483)(cid:476)(cid:493)(cid:476)(cid:478)(cid:495)(cid:480)(cid:493)(cid:484)(cid:494)(cid:495)(cid:484)(cid:478)(cid:494)(cid:3)(cid:490)(cid:481)(cid:3)(cid:495)(cid:483)(cid:480)(cid:3)(cid:498)(cid:476)(cid:495)(cid:480)(cid:493)(cid:494)(cid:483)(cid:480)(cid:479)(cid:16)(cid:480)(cid:3) (cid:478)(cid:490)(cid:494)(cid:500)(cid:494)(cid:495)(cid:480)(cid:488)(cid:494)
(cid:508) Physical Setting and Climate (cid:507)(cid:510)
(cid:509) The Forest: Past and Present (cid:508)(cid:508)
(cid:510) A Rich Array of Organisms and Their Interactions (cid:509)(cid:514)
(cid:491)(cid:476)(cid:493)(cid:495)(cid:3)(cid:637)(cid:17)(cid:3)(cid:496)(cid:489)(cid:479)(cid:480)(cid:493)(cid:494)(cid:495)(cid:476)(cid:489)(cid:479)(cid:484)(cid:489)(cid:482)(cid:3)(cid:481)(cid:490)(cid:493)(cid:480)(cid:494)(cid:495)(cid:3)(cid:480)(cid:478)(cid:490)(cid:494)(cid:500)(cid:494)(cid:495)(cid:480)(cid:488)(cid:3)(cid:3)
(cid:494)(cid:495)(cid:493)(cid:496)(cid:478)(cid:495)(cid:496)(cid:493)(cid:480)(cid:3)(cid:476)(cid:489)(cid:479)(cid:3)(cid:481)(cid:496)(cid:489)(cid:478)(cid:495)(cid:484)(cid:490)(cid:489)
(cid:511) How Is Energy Transformed? (cid:512)(cid:510)
(cid:512) Hydrology: Water Balance and Flux (cid:514)(cid:505)
(cid:513) Biogeochemistry: How Do Chemicals Flux and Cycle? (cid:514)(cid:510)
(cid:514) The Discovery of Acid Rain at Hubbard Brook (cid:506)(cid:506)(cid:509)
(cid:491)(cid:476)(cid:493)(cid:495)(cid:3)(cid:638)(cid:17)(cid:3)(cid:479)(cid:484)(cid:494)(cid:478)(cid:490)(cid:497)(cid:480)(cid:493)(cid:484)(cid:480)(cid:494)(cid:3)(cid:481)(cid:493)(cid:490)(cid:488)(cid:3)(cid:487)(cid:490)(cid:489)(cid:482)(cid:16)(cid:495)(cid:3) (cid:480)(cid:493)(cid:488)(cid:3)(cid:494)(cid:495)(cid:496)(cid:479)(cid:484)(cid:480)(cid:494)(cid:3)(cid:3)
(cid:476)(cid:489)(cid:479)(cid:3)(cid:480)(cid:499)(cid:491)(cid:480)(cid:493)(cid:484)(cid:488)(cid:480)(cid:489)(cid:495)(cid:476)(cid:487)(cid:3)(cid:488)(cid:476)(cid:489)(cid:484)(cid:491)(cid:496)(cid:487)(cid:476)(cid:495)(cid:484)(cid:490)(cid:489)(cid:494)
(cid:506)(cid:505) The Consequences of Acid Rain and Other Air Pollutants (cid:506)(cid:507)(cid:512)
(cid:506)(cid:506) The E(cid:420)ects of Forest Harvesting and Other Disturbances:
Whole- Watershed Manipulations (cid:506)(cid:508)(cid:513)
(cid:506)(cid:507) How Does the Forest Ecosystem Recover After Harvesting and
Other Disturbances? (cid:506)(cid:509)(cid:513)
(cid:506)(cid:508) How Stream Ecosystems Are Integrated with Their Watersheds (cid:506)(cid:510)(cid:510)
(cid:506)(cid:509) What Causes Population Change in Forest Birds? (cid:506)(cid:511)(cid:512)
(cid:506)(cid:510) Scaling Up: Ecosystem Patterns and Processes Across the Valley (cid:506)(cid:513)(cid:511)
(cid:506)(cid:511) How Is Climate Change A(cid:420)ecting the Forest Ecosystem? (cid:507)(cid:505)(cid:506)
(cid:491)(cid:476)(cid:493)(cid:495)(cid:3)(cid:639)(cid:17)(cid:3)(cid:477)(cid:493)(cid:490)(cid:476)(cid:479)(cid:480)(cid:493)(cid:3)(cid:484)(cid:488)(cid:491)(cid:476)(cid:478)(cid:495)(cid:494)(cid:3)(cid:476)(cid:489)(cid:479)(cid:3)(cid:487)(cid:490)(cid:490)(cid:486)(cid:484)(cid:489)(cid:482)(cid:3)(cid:495)(cid:490)(cid:3)(cid:495)(cid:483)(cid:480)(cid:3)(cid:481)(cid:496)(cid:495)(cid:496)(cid:493)(cid:480)
(cid:506)(cid:512) Reaching Out: Hubbard Brook(cid:343)s In(cid:422)uence on Environmental Policy(cid:11)
Management(cid:11) and Education (cid:507)(cid:506)(cid:510)
(cid:506)(cid:513) A Look Ahead: The Forest Ecosystem in the Future (cid:507)(cid:507)(cid:510)
Epilogue: Step into the Forest—(cid:507)(cid:505)(cid:511)(cid:510) (cid:507)(cid:508)(cid:508)
(cid:476)(cid:491)(cid:491)(cid:480)(cid:489)(cid:479)(cid:484)(cid:499)(cid:3)(cid:635)(cid:17) Scienti(cid:421)c Units: Conversions and Abbreviations (cid:507)(cid:508)(cid:512)
(cid:476)(cid:491)(cid:491)(cid:480)(cid:489)(cid:479)(cid:484)(cid:499)(cid:3)(cid:636)(cid:17) Scienti(cid:421)c (cid:45)ames and Lists of Selected Organisms (cid:507)(cid:508)(cid:514)
(cid:45)otes (cid:507)(cid:509)(cid:508)
Bibliography (cid:507)(cid:509)(cid:514)
Index (cid:507)(cid:511)(cid:510)
The Hubbard Brook Ecosystem Study, now under way
for more than 50 years, has been an extraordinarily
productive source of ecological information, derived
from the research efforts of dozens of scientists from a
large number of institutions. The research, conducted
mostly in the Hubbard Brook Experimental Forest and
nearby Mirror Lake in north central New Hampshire,
was initiated in 1963, and has developed into one
of the longest- lasting and most comprehensive
investigations of forest and associated aquatic
ecosystems anywhere. It has also served as a model for
(cid:491)(cid:493)(cid:480)(cid:481)(cid:476)(cid:478)(cid:480)
other ecosystem studies worldwide.
Using the forest as a laboratory, Hubbard Brook
This small corner of (cid:45)ew Hampshire has become the scientists have combined intensive field investigations
most intensely studied piece of landscape on Earth and with powerful, long- term manipulative experiments
the pioneering studies which have (cid:422)owed from this and modeling at a variety of spatial scales that have
idea have made the name Hubbard Brook world famous been designed to answer critical questions about the
among ecologists and foresters. structure, function, and temporal development of
(cid:341)(cid:3)(cid:475)(cid:480)(cid:472)(cid:485)(cid:476)(cid:3)(cid:475)(cid:492)(cid:484)(cid:472)(cid:485)(cid:486)(cid:490)(cid:482)(cid:480) forest and associated aquatic ecosystems and their
component parts. Awareness and understanding
gained from this research undergird the long- term
management of natural resources for water supply,
water quality, wildlife, timber yield, and sustained
forest growth in the region and beyond.
More than 1,500 peer- reviewed scientific
publications from this effort have contributed
new understanding about the structure, function,
and change of terrestrial and aquatic ecosystems,
and have been widely and frequently cited in the
scientific literature. As the project celebrated its 50th
anniversary in 2013, however, we perceived a need
to summarize and highlight the major findings, and
to make them more accessible to a wider audience,
from naturalists and educated general readers to land
managers, policy makers, students, and professional
biologists, including ecologists who might not be
familiar with the Hubbard Brook studies.
The book is organized in five parts. The first
introduces the conceptual framework, the initial
research plans, and the origin of the research.
The second describes the forest ecosystem at
Hubbard Brook, its setting in the White Mountains
of New Hampshire, its history, and its biological
vii
characteristics. Part 3 highlights research findings groups but also by our many colleagues, collaborators,
related to the structure and functioning of these forest students, and technicians as contributors to the Study.
ecosystems. The fourth and longest section highlights When we use the first person plural (“we did this” or
some of the major discoveries from long- term studies “we studied that”), we intend the usage to encompass
and experimental manipulations, including the effects these many individual scientists and their research
of atmospheric pollution (particularly acid rain) and teams, in the spirit of the collaborative research
climate change. The last section, Part 5, covers the efforts that have been a long- standing feature of
educational, policy outreach, and other applications the Hubbard Brook research community. We extend
of the research findings, including the programs of thanks to our many colleagues who have been and
the Hubbard Brook Research Foundation, established are still conducting research at Hubbard Brook for
in 1993 as a support and policy outreach arm of the their important contributions over the years, and
Hubbard Brook Ecosystem Study (hereafter the acknowledge their foresight, intellectual input, and
Study). hard work that have led to the findings presented
Although “Hubbard Brook” is the name of the river in this volume. A full roster of the Hubbard Brook
draining the Hubbard Brook Experimental Forest, scientists, as well as a comprehensive and searchable
the label has gained popular colloquial use as well, list of publications from Hubbard Brook, can be found
referring to both the place and the studies that have on the Study’s website (http://hubbardbrook.org).
gone on there. We use the term “Hubbard Brook” in Although this book is intended as a general
this broad sense—for example, “research was done at synthesis of the research effort at Hubbard Brook,
Hubbard Brook.” When we refer to the river and the it has not been possible to include everything that
context is unclear, we use “mainstem Hubbard Brook,” has been achieved or discovered. We hope that the
which specifically refers to the major stream that flows results we have discussed will engage our readers, and
from the Hubbard Brook valley into the Pemigewasset encourage them to look further into areas that interest
River. Individual tributaries in the valley that feed into them and have not been fully addressed. Finally, the
the mainstem have their own names—Falls Brook and writing of this book has been a cooperative effort by
Zig- Zag Brook, for example. the two of us, and any critical omissions or errors of
As noted, this book contains the results of research interpretation are ours alone.
conducted not only by ourselves and our research
viii (cid:487)(cid:489)(cid:476)(cid:477)(cid:472)(cid:474)(cid:476)
We would like to acknowledge the many institutions
and foundations that have funded research at
Hubbard Brook. Multiple grants from the U.S. National
Science Foundation (NSF) have been the backbone
of funding for the research. In more recent years,
support from the Long- Term Ecological Research
(LTER) program at NSF has provided core funding
for a number of diverse studies, and several grants
from the NSF’s Long- Term Research in Environmental
Biology (LTREB) program have funded long- term
biogeochemical monitoring and the bird population
(cid:476)(cid:478)(cid:486)(cid:489)(cid:490)(cid:498)(cid:487)(cid:480)(cid:479)(cid:482)(cid:488)(cid:480)(cid:489)(cid:495)(cid:494)
studies. Additional support has come from The
Andrew W. Mellon Foundation, the Environmental
Protection Agency (EPA), the National Oceanic and
Atmospheric Administration (NOAA), and from many
of the researchers’ home universities. We particularly
acknowledge the support of Dartmouth College,
Cornell University, University of Connecticut, and the
Cary Institute of Ecosystem Studies in our research
and professional pursuits.
The U.S. Forest Service has been a partner
in the Study from the beginning. Dr. Robert S.
Pierce initiated hydrological, meteorological, and
soil research at Hubbard Brook in 1956, and co-
founded the Hubbard Brook Ecosystem Study in
1963, with Gene E. Likens, F. Herbert Bormann, and
Noye M. Johnson. His successors, Dr. Chris Eagar
and Dr. Lindsay Rustad, and scientists and staff at the
Northern Research Station of the U.S. Forest Service
have all made important contributions to the research
results and to the long- term maintenance of this
research program. We especially acknowledge the
importance of W. E. Sopper, H. W. Lull, C. A. Federer,
J. W. Hornbeck, J. S. Eaton, C. W. Martin, and T. G.
Siccama for their contributions to the development of
this research program. The White Mountain National
Forest is acknowledged for its maintenance of critical
infrastructure, such as roads, inside the forest.
We have benefited from the input and help of
many colleagues during the writing of this book. The
following individuals have offered helpful comments
and suggestions on various drafts: John Aber, Amey
Bailey, Scott Bailey, John Battles, Emily Bernhardt, Don
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