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Analog, Genenc, and Pilot Studies and
Treatment of a Project as an Expenment
INTRODUCTION
The previous five chapters emphasized the application of ecological
knowledge of many general types, but they did not deal directly with
knowledge specifically applicable to particular problems. However, eco-
logical systems often respond to perturbations in a site-specific fashion,
and large or novel perturbations can produce effects not predictable from
basic ecological principles, so specific knowledge is often necessary for
the understanding and prediction of many environmental effects. This
chapter briefly discusses the value and limitations of using specific in-
formation and of treating projects and other environmental actions as
experiments when potentially serious effects cannot be adequately pre-
dicted from information acquired in advance. Observation of the actual
effects of an action can sometimes be the only source of information for
management decisions.
ANALOG STUDIES
An analog study concerns an action similar to one of immediate interest.
The most useful analog study would be conducted in the same area, on
the same species or ecosystem, on a similar scale, and under similar
conditions and would be thoroughly analyzed. Even if the analogs are not
perfect, study of them can be useful in scoping a problem, identifying
major potential effects, and designing appropriate studies.
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76 KINDS OF ECOLOGICAL KNOWLEDGE AD THEIR APPLICATIONS
When a project is similar to many others, analog studies typically
accumulate, especially if they are legally required. For example, in the
legally mandated Maryland Power Plant Siting Program for managing
cumulative impacts, study of the environmental effects of each power
plant should increase the ability to predict the effects of future power
plants (e.g., Maryland Department of Natural Resources, 19841. But the
use of data on one power plant to predict effects of another also requires
knowledge of the differences between the receiving ecological systems
and the differences between power plants. Variations in physical and
ecological conditions between areas can lead to serious errors in extrap-
olation. For example, in the Southern Indian Lake project (Chapter 21),
no specific analog studies dealt with changing of the level of a shallow
lake in a permafrost zone. Because the best analogs-deep lakes in Siberia-
differed in important respects from Southern Indian Lake, investigators
failed to predict the magnitude of bank erosion that occurred and the
consequent changes in water turbidity and mercury release.
In the Lake Washington case (Chapter 20), valuable analogs were avail-
able from experience with nutrient enrichment in temperate lakes in Eu-
rope. In the derelict lands case (Chapter 18), no studies of methods for
diversifying plant communities on previously mined land were available,
but attempts to diversify roadside vegetation informed and motivated the
research studies. Analog studies were of value in the caribou case (Chapter
16) in identifying the major issues, developing field techniques, formu-
lating a study strategy, and locating important resource people who were
familiar with the problem.
Some cases not only relied on analog studies for their design, but were
designed so that they became valuable analogs themselves. The Lake
Washington experience now serves as a model for many lake eutrophi-
cation studies and has contributed importantly to our understanding of
nutrient loading in lakes. The comprehensive review and analysis of the
Southern Indian Lake project increased its instructional value. Analog
studies are most valuable if their results are analyzed and summarized in
an easily accessible form.
GENERIC STUDIES
A generic study is designed to increase knowledge of the physical and
biological phenomena common to a group of environmental problems. It
might be designed to reveal the processes that underlie ecological responses
to manipulations in a particular environment e.g., a study of the effects
of marine oil pollution along coastal beaches or of oil pollution in aquatic
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ANALOG, GENERIC, AND PILOT STUDIES
77
environments in general. It might deal with a restricted subset of envi-
ronmental perturbations, such as the uses of DDT, or try to provide a
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model of the effects of a large class of perturbations, such as pollution
by organochlorides in general. Because ecological effects vary with the
environmental manipulation or insult, the location, the biological com-
munities present, the scale, and other factors, a major question concerning
the usefulness of generic (and analog) studies is the extent to which their
results can be applied to a particular site and problem. The most useful
generic studies identify, characterize, and explain the major ecological
effects of a particular environmental insult or manipulation and provide
a framework for understanding the effects of variations in location and
other factors.
The distinction between analog and generic studies is not always clear.
So much was learned from the Lake Washington experience, for example,
that it might serve as a generic model. A major practical difference between
analog and generic studies is that generic studies are usually well known
to biologists, whereas analog studies are often buried in government or
industry files. Also, generic studies are usually designed to address a
specific question, which means that the postproject monitoring is often
good enough to provide comparative data.
When government and industry cooperate in addressing problems of
mutual concern, studies can be coordinated and research resources used
efficiently. For example, before issuing a permit for exploratory drilling
in state-owned offshore lease areas, California requires extensive studies
designed by a committee of representatives of academe, government, and
industry. Coordination of studies among a number of applicants for leases
in the Santa Barbara Channel allows each to conduct studies on specific
problems common to all drilling programs, such as the effects of discharge
fluids on hard-bottom organisms; results from all the studies can be used
to develop permit stipulations for other applicants. The advantage of such
coordinated endeavors is that duplication is minimized, so more research
is possible.
Environmental studies, for practical reasons, cover limited areas, rel-
atively short periods, and conditions dictated by the time and place chosen.
Moreover, many generic studies involve simulation of the environmental
change of interest, often on a smaller scale and with a narrower range of
variables and variation than encountered in the actual situation. For ex-
ample, the aquatic effects of thermal effluents from a nuclear power plant
might be studied by injection of hot water into a river (if the appropriate
permits required by the Clean Water Act were obtained first). But such
an injection would be made over a much shorter time and a much smaller
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78 KINDS OF ECOLOGICAL KNOWLEDGE AND THEIR APPLICATIONS
area than the usual discharge of effluent, and the injected water might
lack some contaminants present in the normal effluent.
Some other limitations of generic studies are discussed in the review
of clearcutting studies (Chapter 231. The Hubbard Brook clearcutting
experiments of the 1960s (Bormann et al., 1968) were for a long time
accepted as general models of the effects of clearcutting on stream eutro-
phication, soil nutrient loss, and the regeneration potential of land. How-
ever, herbicides were applied after the clearcut in the Hubbard Brook
experiments, whereas rapid revegetation is encouraged in many forestry
operations. Errors in extrapolation from a generic model to a specific
situation can be reduced if generic studies focus on a particular application
and location.
Generic reviews can yield ecological knowledge of great potential value.
They might focus on various topics of potential use to environmental
managers: a group of related problems; natural history and ecology of
particular species, areas, or communities; general approaches to problems;
and broadly useful methods or techniques. A list of useful generic reviews
and related literature can be found in the annotated bibliography on eco-
logical impact assessment prepared by Duinker and Beanlands (19831.
PILOT-SCALE EXPERIMENTS
Pilot-scale experiments are designed to investigate the effects of specific
kinds of environmental perturbations on time and space scales much smaller
than those of a planned project or action. They are appropriate when there
is little confidence in the hypotheses underlying the prediction of effects
and when realistic simulation of the perturbation is possible.
The major uncertainty in connection with pilot-scale experiments is
whether their results can be generalized to similar large-scale phenomena
(Hilborn and Walters, 19811. Although the overall effects of large de-
velopments, such as hydroelectric dams, cannot be realistically simulated
on a small scale, some individual effects of large developments can be
studied experimentally with the traditional scientific procedure of dividing
a problem into its components for analysis.
Experiments were used to advantage in the derelict lands case (Chapter
18), to investigate the performance of groups of plants under different soil
conditions; there is no obvious reason why the results of these studies
cannot be generalized to larger-scale applications. Pilot-scale experiments
were conducted to study the potential effects of the Alaska pipeline on
caribou movements (Cameron et al., 19791. A variety of small-scale
experiments were conducted on the effects of DDT (Chapter 241. Labo
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ANALOG, GENERIC, AND PILOT STUDIES
79
ratory and field experiments were used to investigate toxicity in several
species and to determine residence time of DDT under different environ-
mental conditions. Field and laboratory experiments confirmed the oc-
currence of bioaccumulation. The Atomic Energy Commission program
for studying the effects of nuclear radiation (Chapter 22) is a good example
of the combination of a variety of laboratory and field experiments to
improve understanding of a complex problem.
TREATING ~ PROJECT OR ACTION AS AN EXPERIMENT
If reliable prediction of the ecological effects of a project or action is
not feasible, even with extensive field investigations, the limits of pre-
dictive ability should be openly recognized, so that planners, decision-
makers, and managers can take into account the uncertainty of the eco-
logical outcomes of particular actions (Paine, 19811. Viewing a project
or action as an experiment can aid in designing a program to monitor
effects. Such monitoring can have two major advantages: the detection of
unexpected effects can be used as a basis for altering procedures (Holling,
1978), and the monitoring information can be used in the planning and
design of similar projects or actions.
The idea of a project as an experiment can be applied to a variety of
environmental problems, particularly in impact assessment and resource
management. As Beanlands and Duinker (1983) pointed out, however,
most impact assessments concentrate on the prediction of impact almost
to the exclusion of followup studies to determine actual impact. Even in
postproject studies, little effort is spent in determining whether predictions
were incorrect and why (Larkin, 19841. An attempt by a study group to
audit the results of a large number of impact assessments in the United
Kingdom revealed several major impediments to learning from such ex-
periences (Anonymous, undated): predictions were absent or vague, mon-
itoring schemes were inadequate, documentation was poor, and relevant
parties were unwilling to cooperate. Chapter 10 offers some general sug-
gestions for designing monitoring studies to make them more useful for
planning projects or actions. Among the projects described in case studies,
the best examples of the idea of a project as an experiment are the Garki
malaria project (Chapter 15), the project to raise the level of Southern
Indian Lake (Chapter 21), the eutrophication and cleanup of Lake Wash-
ington (Chapter 20), and the efforts to protect caribou during development
of a hydroelectric dam in Newfoundland (Chapter 161.
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80 KINDS OF ECOLOGICAL KNOWLEDGE AND THEIR APPLICATIONS
Walters and Hilborn (1976) and Walters (1984) have suggested that
natural resources can be managed experimentally, not only by following
up the consequences of management actions, but by basing management
decisions on the need for increased knowledge. In that paradigm, managers
must weigh the trade-offs between the value of potential immediate yield
and the value of information. The value of information is greatest when
understanding of the system is poor and the consequences of incorrect
decisions most severe.
Representative terms from entire chapter:
analog studies
