Journal of Aquatic Ecosystem Health 3: 5-14, 1994. M. Munawar (ed.), Aquatic Ecosystem Health and the Ecological Significance of Bioassay Techniques. © 1994 Kluwer Academic Publishers. Printed in the Netherlands.

Ecosystem health through ecological restoration: barriers and opportunities

John Cairns, Jr Department of Biology and University Center for Environmental and Hazardous Materials Studies, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061-0415, U.S.A.

Keywords: ecological restoration, sustainable use, ecosystem health, environmental policy, environmen- tal management

Abstract. It is quite possible that no ecosystem on the planet is totally free of anthropogenic effects. Changes in the ozone layer, airborne transport of contaminants, and the persistence of pesticides and other chemicals, coupled with biological magnification, implies that even remote areas are probably not comparable to their condition before the industrial revolution and the recent explosion of human population. Theoretical ecologists have attempted to isolate their theories and studies from anthropogenic effects with varying degrees of success. However, finding ecosystems free of the effects of human society is becoming increasingly difficult, partly because of the global nature of pollution problems. Regrettably, many academicians are not educated in policy development as they work toward B.S., M.S., or Ph.D. degrees in the sciences. As a consequence, scientists are surprised to learn that a politically-appointed individual, experienced in law or some other non-scientific field, usually has final decision-making authority over policy that affects ecosystems. Scientists must understand that policy links science to social, economic, and legal societal values and needs. Finally, aside from the fact that policy or lack thereof now affects all of the planet's ecosystems, policy most likely will also determine which areas of research are funded. While some scientific studies could be carded out with personal funds, these are not particularly common in mainstream science and, therefore, obtaining financial support for ecosystem studies for the remainder of this century and probably early in the next will depend increasingly on societal policy other than purely science policy.

'It is easier to move a graveyard than to change a curriculum.'

Jorges Clemenceu

1. Introduction

If the term curriculum is broadly defined as 'a course of study,' then the Clemenceu quote can be applied to the protection and restoration of ecosystems. The change that needs to be made in perspective is that scientists should place a higher priority on governmental and industrial policies that have the potential to affect the ecosystems of interest to them. Colleagues often tell me that they are theoreticians and know nothing about politics. However, people who believe academe is free of political maneuvering probably also believe in the Tooth Fairy and Santa Claus. Academic politics may arguably require far more skill and persever- ance than any other political arena. Finding the

time for affecting policy on ecological restora- tion is another consideration; however, since the ecosystems are being impaired at a frightening rate, one is either forced to take a stand in the policy arena or find a field, other than ecology, of interest. The opportunity to study ecosystems that have suffered no anthropogenic effects probably disappeared at least two decades ago, although a widespread concern about global effects has come some time after the reality.

2. Ecosystems services: a possible congruence between science and public policy

Scientists are interested in how ecosystems func- tion. Those functions of value to society (pos- sibly all), such as maintenance of water qual- ity and atmospheric gas balance, form a focal point o f interest for both scientists and policy

makers (e.g., Westman, 1977 among others). The functional attributes of ecosystems should be termed services because this terminology has to be understood by policy makers if the bene- fits to human society are explicitly stated. From a scientific perspective, functional attributes are often considered unsatisfactory measurements to make because many are highly variable, season- ally dependent, and differ from one ecosystem to another. Altemately, the benefits to human soci- ety are most likely to be understood if described in non-scientific terms such as functional attributes (Suter, 1990). Additionally, society has a gen- eral awareness of the concomitant rapid destruc- tion of ecological systems and human population increase, which together will result in inevitable and unprecedented reduction in ecosystem ser- vices per capita unless drastic alteration of both of these trends is accomplished by early in the next century. Monitoring ecosystem services per capita is one approach to assessing the success with which environmental restoration has sus- tained or improved human quality of life. This approach has been used to assess food security - the World Watch Institute reports that global grain production per capita has been falling since 1984 (Brown, 1989). The calculation of ecosys- tem services per capita as an assessment tech- nique can profitably be extended to other ecosys- tem services such as carbon dioxide storage, waste degradations, etc. Regrettably, the majority of ecosystem services has not been quantified to the extent necessary to calculate ecosystem ser- vices per capita. Clearly, approximations of these amounts are possible with present information. Considerable uncertainty exists, however, about the relationship between biodiversity and ecosys- tem services. From an anthropocentric point of view, one might also wish to have better informa- tion on the minimum level of ecosystem services per capita permitting long-term sustainable (e.g., non-degrading) use of the planet's ecosystems as life support systems.

3. Development and implementation of policy options

The ways that policy options are influenced and their implementations are affected are, in my experience, somewhat of a mystery to the aver- age scientist. Moreover, when the topic of pol- icy does come up among scientists, they tend to view it as a scientific rather than a political exercise. Academicians in the sciences simply are not educated in policy development and are surprised to find that a politically-appointed indi- vidual, experienced in some non-scientific field, has final decision-making authority over major policies that affect ecosystems.

The development of policy based on environ- ment risk provides some interesting insights into how ecological restoration policy might devel- op. Executive agencies charged with administer- ing and implementing natural resource or envi- ronmental regulatory legislation must employ risk management and risk mitigation, while risk assessment serves as the scientific basis for these administrative activities (e.g., U.S. National Research Council, 1983 among others). Man- agement and mitigation are decidedly different activities than the development of risk assess- ment methodology and entail more than basic and applied research. In fisheries management, it is frequently stated that the best science in the world will not make good policy if it is not accepted by the general public. This is also true of environ- mental management, which has had much less time to evolve. The risk assessment practices, possibly stimulated by the publication of the U.S. Environmental Protection Agency Science Advi- sory Board documents promoting risk-based reg- ulations, seem to be evolving into an integrated process involving three steps.

(1) Risk assessment is scientifically-based and integrates data and information to characterize risk by: identifying resources at risk; linking cause and effect through stress-response studies; deter- mining exposure through modeling or monitor- ing; comparing the estimated environmental con- centration (EEC) with the receptors at risk.

(2) Risk management is policy-based and defines assessment questions that incorporate socio-economic and legal values to protect human health and the environment.

(3) Risk reduction involves mitigative actions to minimize exposure when scientific and societal risk is deemed unacceptable by risk managers.

The field of ecological restoration has already begun a similar evolution into at least four com- ponents.

(1) Prediction of ecological recovery trends is scientifically-based and integrates data and infor- mation to predict both trends and outcome if restoration is undertaken in a particular way. This requires: identification of the desired outcome compatible with societal and ecological needs; determination of the potential colonizing species and whether or not they will require assistance to reach the damaged area; determination of the chemical/physical/biological conditions that will facilitate recolonization by appropriate species; estimation of risk from undesirable exotics or inappropriate native species; estimation of accept- able and unacceptable deviation from predicted trends; determination of both favorable and unfa- vorable interactions with adjacent ecosystems.

(2) Restoration management is policy-based and defines restoration questions that incorporate socio-economic and legal values in establishing the degree of ecological restoration and the tem- poral and spatial scales. It is important to inte- grate the scientific aspects of restoration into soci- etal components to prevent the destruction of the restored ecosystem. Figure 1 illustrates how this might be done.

(3) Quality control monitoring should be used to determine whether pre-established quality con- trol conditions are being met. Once the ecosys- tem health (to use a human health metaphor) has been restored, periodic checks should be made of attributes closely associated with ecosystem integrity to ensure that the restorative efforts are not negated by inappropriate societal actions sim- ilar to the ones that produced the damage. If they are negated, actions should be considered to mod- ify human behavior in a manner that facilitates the maintenance of the restored system.

(4) Mitigation is usually interpreted in the restoration context as a replacement for a lost ecosystem or lost ecosystem services. In Web- ster's Dictionary, the second definition of mitiga- tion is to make less severe, violent, cruel, intense, painful: or to soften or alleviate. In some cases, mitigation has involved the preservation of a wet- land elsewhere to mitigate the loss of a wetland in a particular location. Basically, this takes the policy position that slowing the rate of loss of natural ecosystems softens the loss of a partic- ular ecosystem. The mind set that views this as acceptable can only be altered by improved envi- ronmental literacy of the decision makers and not by new scientific evidence. Mitigation is also used to mean replacement of lost ecological ameni- ties mostly as a result of habitat destruction. The appropriate degree of replacement is a societal value judgment. A mix of economic, political, and social factors may well outweigh the scien- tific evidence in influencing the final decision. Ecologists may deplore the actions of the deci- sion makers, but decision makers will only have as much ecological literacy as their degree pro- grams in political science, public administration, land-use planning, economics, or public policy have demanded. Educational systems cannot fail to acquaint them with how science works and, more specifically, the basic elements of ecology. Environmental literacy is a goal for students in all disciplines, not just biology.

4. Relating information generation to the decision-making process

Information generated by scientific research must be clearly demonstrated as useful in making deci- sions important to the policy of the sponsoring organization. With common technologies, infor- mation can now be integrated with a variety of other, quite diverse types of information. Thus, it is essential to study not only policy but also to study the other diverse types of information generally required to make policy decisions on matters that transcend the capabilities of a single specialty or discipline. In short, scientists predomi-

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Human Acceptability

Threshold

Human Desirability Threshold

Ecological Desirability Threshold

Ecological Acceptability Threshold

0 1 2

Human Value

--cological Valu 4uman Valu~ 3el

A0 Unacceptable Unacceptable

A1 Unacceptable Acceptable

A2 Unacceptable Desirable

B0 Acceptable Unacceptable

B 1 Acceptable Acceptable

B2 Acceptable Desirable

CO Desirable Unacceptable

C1 Desirable Acceptable

C2 Desirable Desirable

Fig. I. Project assessment matrix (reprinted with permission from U.S. National Research Council, 1992, p. 63).

nately involved in scientific aspects of ecologi- cal restoration must be willing to become more deeply involved in the three M's: management, monitoring, and mitigation. To do so at the oper- ational level means greater understanding of, and perhaps even involvement in, policy development and environmental management.

Many management decisions are so urgent that they cannot wait for the traditional scientific pro-

cess of hypothesis, research, validation, verifica- tion, and approval by mainstream science. As a consequence, information that can be generated before the decision is the most likely to affect that decision, but more substantive information should be gathered after the decision has been made.

5. Ecosystem services/policy options

The development of policy options related to this discussion is based on four assumptions: (1) ecosystem services are important to human quality-of-life, (2) the continued destruction of ecosystems and the concurrent rapid increase in human population size are serious threats to ecosystem services, (3) the rapid global loss of species intimately connected with the loss of habi- tat will also impair ecosystem services, and (4) healing damaged ecosystems will enhance both the quality and quantity of ecosystem services.

There are five basic policy options regarding the relationship of ecosystem services and human population size: (1) continue ecosystem destruc- tion and population growth at their present rates and see what happens before any action is taken; this would mean dramatic erosion of ecosystem services per capita in the near future, (2) adopt a policy of no-net-loss of ecosystem services, which means that a balance between destruction and repair must be achieved at all times; this would still mean a decline of ecosystem services per capita because more and more people would be sharing an unincreasing amount of ecosystem ser- vices, but the per capita amount would decline less rapidly than option 1, (3) exceed a non-net- loss of ecosystem services, which means develop- ing a policy of healing or restoring ecosystems at a more rapid rate than their destruction; this would probably still mean a loss of ecosystem services per capita at the present rate of global population increase, (4) stabilize human population growth and exercise option 2, which would maintain the status quo on ecosystem services per capita, and (5) stabilize human population growth and restore ecosystems at a greater rate than damage, which would improve ecosystem services per capita.

If we decide to restore ecosystems, there should be three basic ecological components of a national and global restoration strategy: (1) restoration goals and assessment strategies should be set for each ecoregion, (2) principles should be established for priority setting and decision making, and (3) policy and programs for federal and state agencies (for the United Nations) should

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be redesigned to emphasize ecological restora- tion. The U.S. National Research Council (1992) book gives the following illustrative goals for the United States for restoring aquatic ecosystems between now and the year 2010: (1) wetlands - restore 10 million acres (out of 117 million impaired or destroyed since the year 1800); (2) rivers and streams - restore 400,000 miles (12 per cent of the 3.2 million miles presently con- sidered impaired or damaged); and (3) lakes - restore 2 million acres (out of 4.3 million acres presently degraded). Although precise replication of predisturbance condition will rarely be possi- ble, achieving a naturalistic assemblage of plants and animals of similar structure and function to the predisturbance ecosystem should be possible in most cases. However, if one adds the attributes of self-maintenance and integration into the larger ecological landscape in which the damaged patch occurs, both the temporal and geographic dimen- sions of the study area increase substantively. If exploratory restoration projects are added in each ecoregion, then the number of acres and the per- cent or actual size of the restored aquatic ecosys- tems presented above do not appear excessive. The recent World Scientists' Warning to Human- ity states 'Human beings and the natural world are on a collision course.' Ecological restoration is a means of buying more time for human society to develop lifestyles less threatening to natural sys- tems and for ecologists to develop more robust methods for restoring the earth's damaged sys- tems.

6. Developing a restoration strategy

A restoration strategy should consider the follow- ing assumptions.

(1) Landscape level restoration must integrate aquatic and terrestrial information and restoration and must include studies of airborne contaminants and changes in groundwater quality.

(2) No landscape level ecological restoration will endure unless the human society in the region understands and concurs with the objectives and goals.

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(3) A monitoring program should be estab- lished at the outset of the restoration effort to determine how closely the actual trends meet the predicted trends. Monitoring is used in this con- text to mean surveillance to ensure that previously established quality control conditions have been met. Therefore, it is essential that a set of criteria, including rate of change, be established to determine whether the ecological restoration is a success or failure. If it is a failure, an explicitly stated program or mid-course project redirection occur, including cost adjustments, if any.

(4) Even after the ecological restoration objec- tives have been met, monitoring should continue, although probably at a reduced frequency and with fewer attributes to ensure that the ecologi- cal integrity has not been impaired. Criteria for both types of monitoring should be established well before the project begins.

7. Protection of existing unimpaired eco- systems

Launching a substantive effort in ecological restoration makes no sense if societal attitudes remain unchanged toward the rate of loss of the few remaining unimpaired or relatively unim- paired ecosystems. One of the fears regularly voiced about the field of restoration ecology is that it will provide an excuse for continued eco- logical destruction. There is some merit in this argument if those carrying out the destruction, especially with government approval, can escape the costs of ecological restoration. However, the troubling point here is that, if we wait until all ecological destruction stops before we start major ecological restoration efforts, we will not have the experience or data base necessary to make a scientifically justifiable effort when the opportu- nity comes. Therefore, restoration ecologists will, for a transitional period at least, be placed in the awkward position of healing damaged ecosystems while their destruction continues at arate in excess of the healing. There are four major reasons for carrying out ecological restoration under these conditions: (1) if carried out properly, restora- tion will enhance the development of predictive

models, methodology, and the like, (2) costs of restoration will become better documented, (3) restoration is required for compliance with regu- latory laws and statutes, and (4) restoration will preserve some habitats that are in scarce supply and might otherwise be lost.

Determining the degree of protection needed before a large-scale ecological restoration is justi- fied is a difficult social decision despite the num- ber of people who deplore ecological destruction. Authorization for deliberate destruction, such as channelization of a river or digging a ditch beside the river as was done for the Kissimmee River, should either be non-existent or vanishingly rare if non-ecological objectives can be met in other ways. The destruction of old growth forests inhab- ited by the spotted owl in the Pacific Northwest would not even be a debateable issue if the cost of restoration to predisturbance condition were included in the market cost of the timber. In those truly exceptional cases where such dam- age is authorized, bonding for restoration to pre- disturbance condition should be a sine qua non. Penalties for accidental spills should be vastly increased because most spills are due to careless- ness, drunkenness, or shoddy management, and bonding against ecological accidents should be as commonplace as accident insurance on vehicles. Finally, damage to a restored ecosystem or one being restored should be as costly (at least) as the amount spent on the restoration effort to that point.

It seems highly improbable that any of these could occur without a vast increase in environ- mental literacy and understanding. Educational programs can begin with the recommendations of groups such as the Society of Sigma Xi (Black- burn, 1992) and a number of academic institu- tions (Talloires Declaration, 1990) in implement- ing changes in the educational system that will make this possible. At the same time, comparable efforts must be made within industry, govemment, and in the public at large in a variety of ways. The rapid rate of population increase, in at least some countries, and the increased affluence and level of energy consumption in others provide very little time for these major social adjustments.

8. Policy on constructed ecosystems

In a symposium sponsored by the Ecological Soci- ety of America and the proceedings that followed, Magnuson et al. (1980) used the word enhance- ment to mean improving the current state of an ecosystem without reference to its initial state. There was an indication that this might lead an ecosystem further from its initial state by adding desirable man-made features and suppressing undesirable natural features. Cairns (1986) mod- ified this concept and used the term alternative ecosystems instead of enhancement because some federal agencies were using the term in an en- tirely different context. Recently, Kustler & Ken- tula (1990) have used the word creating for the replacement of wetlands. Hammer (1989) has used the word constructed for a somewhat simi- lar situation. The U.S. National Research Council (1992) provides a useful series of definitions on restoration and related topics that were being used at the time when that book was published.

It is a sine qua non that ecological repair is preferable to neglect of damaged ecosystems and that an ecologically superior condition, even in a form different from the original state, is probably more beneficial than the degraded state. One can also make the case that a State such as California, which has lost 91 per cent of its wetlands (U.S. National Research Council, 1992), would be jus- tified in replacing some of the lost wetlands on sites that had not previously had wetlands. These wetlands should be appropriately connected to the hydrologic cycle and not be caricatures of wet- lands. My own State of Virginia, which has lost only 42 per cent of its wetlands since 1800 (U.S. National Research Council, 1992), might well develop a quite different policy on constructed wetlands than California.

Another promising use for constructed ecosys- tems of all sorts is where such ecosystems would serve as corridors between two or more relatively undisturbed ecosystems. Fragmentation of the ecological landscape is well known, and the pos- sibility of ecological restoration to provide cor- ridors between relatively intact ecosystems rep- resents a major opportunity to reverse the trend

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from increasing fragmentation toward large-scale well connected ecosystem components. In many instances, such corridors could be developed with relatively minor social and economic disruption. After all, no one would attempt to place a corri- dor where a 70-story office building now stands. However, landfills, abandoned farm lands, or pre- viously irrigated lands (to give a few illustra- tive examples) might be an excellent means of using constructed ecosystems to connect ecosys- tems with robust integrity.

Another factor in the policy decision con- ceming wetland construction might be consider- ation of how many presently impaired wetlands might be repaired or restored without major social and economic dislocations. If the wetlands were merely drained for grazing, agriculture, or some other purpose that did not involve massive con- struction, re-connection to the hydrologic cycle should be relatively easy, and the economic and social disruption would be relatively minor. Under these circumstances, the justification of constructed or created wetlands seems less com- pelling.

9. Restoration banks/no-net-loss policy

Three basic societal options exist regarding the relationship between ecosystem destruction and repair.

(1) Ecosystem destruction exceeds the rate of repair - the present situation.

(2) A no-net-loss situation is developing in which the rate of ecosystem repair exactly balances the rate of destruction.

(3) The rate of ecosystem repair exceeds the rate of destruction.

Regrettably, while ecosystems may be severe- ly damaged in a matter of hours (e.g., the Exxon Valdez oil spill), natural recovery or restoration to an approximation of predisturbance condition may take years, decades, or longer. A true no-net- loss policy would require instant replacement o f

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damaged ecosystems! Since this is operationally impractical, an alternative policy would be to develop an 'ecosystem bank' in which ecosystems are repaired and remain there until an organiza- tion responsible for damaging an ecosystem buys one or more to replace the one damaged. This strategy actually would build ecological 'capital' in anticipation of future losses. It could even be operated as a free enterprise system. The 'interest' generated by this ecological capital is, of course, in the form of ecosystem services. Bonding would increase the likelihood of private sector involve- ment if the amounts of money are adequate. If the private sector shows no interest, the amounts of the bonds are probably inadequate. Taken in a global perspective, this could mean that a no- net-loss of ecosystems might be achieved glob- ally but not nationally or regionally. Furthermore, some categories of ecosystems could be totally destroyed and replaced with dissimilar ecosys- tems if this bank is used injudiciously.

Possibly the solution is to have some form of world bank to maintain the no-net-loss balance at a global level with national and/or regional banks to maintain a no-net-loss balance on a small- er scale. The banking analogy is troublesome because of bank scandals in the United States and other countries in recent years. Nevertheless, the requirement that ecological capital cannot be destroyed without both a financial and ecological responsibility should be well established, and this seems the best initial way to do so.

I0. Environmental bonding as a means of ensuring ecological responsibilities are met

Although the number of ecoaccidents should be markedly reduced because most are due to human failings, such as drunkenness, fatigue, drugs, fail- ure to read the instruction manual, or belief that no accident could possibly occur (to give a few illustrative examples), they cannot be reduced to zero. In many cases, companies will try to evade responsibility for damage to the environ- ment as they have in human health by claiming that there is no scientific proof of harm at the time

the damage occurred or they may go bankrupt. Industries, individuals, and even state and federal governments should be bonded by private insur- ance companies for ecological restoration follow- ing both accidental and deliberate environmental damage. Bonding has been reasonably success- ful for surface mining and a few other activities that are environmentally damaging. The situation could, of course, be improved, but this does pro- vide a source of funding for ecological restoration should the organization that caused the damage go bankrupt or deny responsibility. On the other hand, environmental activists have insisted, in some instances, on bonding for unlimited finan- cial responsibility for an indefinite time period. Of course, no insurance company is likely to make a reasonable profit under those circumstances and will probably itself go bankrupt. If the bonding organization, even one as respectable as Lloyd's of London, loses more heavily than it expects for a substantial stretch of time, alternative sources of bonding may be difficult to find when other bond- ing companies see their competitors' difficulties. Therefore, bonds will probably not be issued for unlimited sums of money for indefinite periods of time. In those cases where desirable ecological restoration is not possible with the funds provided by the bonding company, an ecological trust fund should established to handle the differences.

An additional reason for establishing an eco- logical trust fund is that federal and state agencies might become too prescriptive in order to make certain that the system is as fully restored as pos- sible with the least uncertainty. However, this means that very little basic information will be generated, and the traditional funding agencies for research will unlikely undertake a substan- tive amount of research in this new area with- out seriously undermining their support for other areas. As a consequence, each ecological restora- tion project should be, at least in part, experimen- tal so that the ecosystem is healed but also so that science obtains new information that will improve the capabilities for ecological restoration.

11. Developing a science court

Ecological restoration and quantifying no-net- loss of ecosystems are basically the responsibility of the scientific community, with some help from engineers in developing hydrologic models and the like. Regrettably, most of the judgments on the scientific components of ecological damage and restoration, quantification of no-net-loss of ecosystem services and habitat, and the like are carried out in courts of law rather than science courts (Rankin, 1991). While judges and attor- neys may have a good grasp of legal requirements, their understanding of science is not always exem- plary. Worse yet, attempts are made to fit the scientific evidence into the requirements of the legal system, and persons with no robust qualifi- cations in science often make judgments on the adequacy of the science when the inevitable clash of expert witnesses occurs (e.g., Thomas, 1992). In numerous situations, the scientific component could be isolated from the regulatory, policy, and management components, and the evidence could be presented in a manner to which the scientific community is accustomed. However, the scien- tific community must take pains to see that the decision not only meets general scientific stan- dards but is also intelligible to those in other disciplines who must incorporate this informa- tion into a mix of other types of information to make a reasoned decision. It is a sine qua non that this would be carried out by practicing scientists well acquainted with the difficulties of working in the field, especially when the data gathering is affected by episodic events such as floods or droughts. These scientists should also have been exposed recently to peer-review through publica- tion in scholarly journals and the like. They could be selected by a U.S. National Research Coun- cil to ensure not only that their scientific cre- dentials are robust but also to ensure that none of their activities represent a conflict of inter- est. Service through the U.S. National Research Council would serve another purpose of obtain- ing release time from one's academic institution, which might not occur if carried out under the auspices of a less well recognized academic orga-

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nization. With increased pressures for teaching, the research and professional service components are suffering at many academic institutions, and only societal awareness of the importance of a science court would change the mind set of those who write position descriptions and report to leg- islatures.

Acknowledgements

I am most grateful to four reviewers, Robert Atkinson, Karen Holl, B. R. Niederlehner, and Mara Sabre for comments on early drafts of this manuscript and to Anthony Maciorowski for com- ments on risk policy as well as scientific policy. I am also indebted to Teresa Moody, who tran- scribed all of the dictation for the manuscript and processed the many changes on the word proces- sor. Last, but not least, my editorial assistant Darla Donald prepared the manuscript in a form suitable for publication in this journal.

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