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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. 75
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
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 - 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
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
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.
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.