Sustained forests; sustained profits
Sustained forests; sustained profits
| [ HOME | Lasting Forests Home | Table of Contents | The Finder | Glossary ] |
The Dow Jones Corporate Sustainability Concept is that sustainability-driven companies achieve their business goals by integrating economic, environmental, and social growth opportunities in to their business strategies. The companies pursue these opportunities in a proactive, cost-effective, and responsible manner today so that they will outpace their competitors and be tomorrow's winners. There are five corporate sustainability principles under the topics of Technology, Governance, Shareholders, Industry, and Society. These may be used to identify and rank companies for investment purposes. They are said to facilitate quantifying sustainability performance as a company pursues opportunities of meeting market demand for sustainable products and services and reducing or avoiding sustainability risks and costs.
Sustain is a word, which like Hunpty Dumpty in Alice in Wonderland said "...means just what I choose it to mean." It has been a problem since 1897 when the Organic Act of the Forest Service was written, further in 1920, maximum sustainable yield in fisheries in the 1940's, optimum sustainable yield in fisheries in the 1958 Oceans Convention, and in the 1944 Sustained Yield Forest Management Act. Sustain is a verb. It is something that a manager can do to a system. A population of deer may be a system and thus a deer manager may sustain the herd. The difficulty with the concept is one about the performance measure for the system. How will the manager or the client know that the herd has been sustained? How might an opposition attorney in a court case argue that the herd had not been sustained? What if the population is below a desired level? Should that population be sustained? If excessive and causing problems, should that population be sustained? These are the types of issues encountered with the word and its meaning.
Maser (1994) in Sustainable Forestry is said to have devised a new theoretical framework for forestry. It relies on adaptive management, an ad hoc process with continual feedback and adjustments.
Schallau (1989) observed how plans to export timber (the continuous flow from public lands into the mill) changed the economics of a region and thwarted the intent of the laws to provide employment. In response to changes in world markets and demands for wood, continual harvests could cause prices to drop if there are over supplies, creating further problems. Soon it was realized that a constant supply of wood, "the yield from the land" was not what was intended in the formulation of early law and policy but yield of products from the mills. This idea was soon rejected (for example, since excessive milling capacity may be attracted but impossible to be used over the long run) and replaced with "benefits." An enterprise might produce some product for a very long time but if the supply influences the price, then continual work can bankrupt the company. The raw material inputs, the sustained yield from the field, might hasten the bankruptcy...clearly not the intention of the law or or managers. Sustained yield may not be a good thing. Surplus may be as important to manage as shortage.
I once questioned the propriety of widespread boll weevil control in a federal agency. If successful, cotton supplies would increase, the price drop, and the cotton farmers may be worse off than was intended. I was encouraged not to follow that line of thought.
In John Hof's chapter in Coactive Management called "Sustainability Revisited", he listed the advantages of non-declining timber yield (a la 1925) but was quick to point out that such policy when used in conventional computer models caused increasing harvests and imposes very high costs due to the constraints used in the model. He said that non-declining yield is grounded in an appeal to stabilize a harvest or conservation for the future."... These rationales are actually served better by an alternative approach to strict nondeclining yield constraints..." He argued for a Maximin strategy, maximizing even harvest levels which he said seemed to be more stable, more equitable, and had lower opportunity costs than a rigid non-declining yield procedure.
Sustain has one dimension of meaning which is "without interruption." Even the words used to express this cause confusion. "Continual" allows interruptions and variability (regular or frequent) while "continuous" means uninterrupted in time or sequence. In the natural resource world continual events are dominant. Of course endangered species presence must be continuous (but even with such species, meta-population theory has entered and questions abound about whether small populations of a species far removed from a healthy large population can every be considered to be continuous. Even tree growth is continual, but because it is cumulative, the interruptions are not seen. Every person feeding birds knows that the populations at the feeder differ annually. They are continual. To mention annual differences brings into focus the issue of time and the planning horizon. For stability to be meaningful a period of interest must be specified. Stability is evaluated relative to a second, a week, or a 100-year period, etc. It is influenced by intrinsic phenomena (like circadian forces), migration, and location (like pollution or pesticide applications). What is an appropriate time horizon? The shorter, the less likely a manager is to be able to sustain a population. Few populations can recover from a crisis situation or low state in a short period. Laws related to sustained yield speak of "into perpetuity." Few people would bet that they could stabilize a system in 2 years (things are too variable!) but would be willing to attempt it over the long run. No one will tolerate a claim of a system being sustained for 2 years, but it failed in the third year, thus it was sustained! The question of what is the longrun and perpetuity remain. To compute, there has to be an end condition, at least a tentative one, and it needs to be large enough to accommodate several human generations and the age of trees. It must be computed or there will never be a realistic engagement by decision makers of whether the future conditions might be tolerable or sufficient, even for today's people. Within Lasting Forests it is 150 years and analyses are typically done "sliding forward" or auto-regression-like procedures, dropping the first year of data or information, adding the latest data, and projecting within models for the next 150 years. (Constraints perceived about future needs are also used to accommodate analyses for the longrun, the longterm, and perpetuity.)
I want to leave this one aspect of sustainability, constancy, to address the one most often associated with the word. However it needs to be as clear as possible. It is one dimension of a complex concept. I take it to mean that there is some performance measure, so way to see a system and that that measure can be approximated or estimated and plotted. The plot, then, of a sustained system is continual, over a long period, with gaps or discontinuities in the measure few and brief (of short duration). Because there are gradations in all three of these elements, sustainability is a continuous, multivariate expression (and thus rarely for discussion with the "masses", those pre "formal operations.").
The difficulties are seen in the sketch.
Which system is sustained? More sustained than others? What is the maximum discontinuity allowed? Is C the only one sustained?
Sustaining may mean maintaining the status quo. If people like things as they are, then sustaining such things seems reasonable. Liking may not be the best criterion and so the debates over bringing modern civilization to primitive tribes, over the impacts of ecotourism on sensitive cultures, and even the advantages of public schooling over home schooling remain. "Things as they are" would have meant foregoing TV, the internet, computers, airtravel, autos, and... Perhaps holding the status quo is not what most people mean by sustaining things. Perhaps sustaining family farms and businesses is just protectionism for personal investments, not for cultural or sociological reasons?
"Sustainable" linked with yield by foresters, has been linked with "development" to be sustainable development and that is taken to mean "meeting the needs of present generations without compromising the ability of future generations to meet their needs" (Our Common Future 1987 and WCED 1987). Often quoted and politically useful, the phrase has been addressed in terms of "economically viable", "socially just", and "environmentally appropriate"...with each generating its own debate. The US Forest Service said in 1994 it was to "promote the sustainability of ecosystems by ensuring their health, diversity, and productivity." The issues include disparities in consumption, gender issues, international markets, the history of political action, human health, and the knowledge and abilities of local populations to deal with any assistance or new designs for betterment. In 1995 the Forest Service wrote of "sustainable management" (as if a system might be left untended or that anyone would admit to variable intensities of management over time.) Sustaining a system is very difficult for few people know what that means. Sustaining anything, whatever it means, is difficult. Consider sustaining a conversation, a marriage, a university program. Within biology the rule is migrate, mutate, or die...hardly the admonition for sustainability. Politicians campaign, promising change. Music is unsustained, patterned sound. The move toward ecosystem management is hardly to sustain the "multiple use" policy. Mysticism abounds; UFOs circle; palm readers cluster at universities; farmers rely on the almanac. We praise Jefferson, insist that other countries adopt democracy, but ignore his insistence that democracy must have an educated electorate. Some things are readily sustained. We must not sustain the ambiguous concepts of sustainability.
In Lasting Forests the concept of development as used by urban planners and agencies providing assistance to developing countries is similar to the meaning of management used throughout our work. We are manipulating a system and while development seems to imply some upward movement or improvement (as in regional development), we see it more broadly but questions remain. We retreat to studying the word itself. Having teased out the issue of continuity, we can now address stability. In most conversations about sustainability, the topic reverts to (at least connotations of) stability. They dance around "growth" and lines reflecting it, around "durable", "future prospects",and replicating performance. Stability is a concept of evolutionary persistence. Perhaps some systems are innately unsustainable?...and efforts ought not to be made to do so. Some people suggest that an endangered species population is just such a subsystem, doomed, and thus efforts should not be spent on helping it "hold its own."
To address stability, it seems necessary to ask first, "of what"? In a simple system, say of deer or elk, the number of deer may be the performance measure. (It could be cumulative kilograms of processed meat over 5 years, total antler point scores, weight, hides, sightings by recreationists, logarithm of the annual harvest, etc.) For societies or for ownerships or regions there is the need for a complex scoring mechanism. Lasting Forests has devised such a scoring mechanism, a performance measure. As other performance measures, it is not perfect. It is an index and subject to all of the limitations of such constructs. It is believed to include the major dimensions, the dominant factors, the significant features of a wildland system having many diverse and differently-weighted values to different people. In this paper it is called Q and is assumed for discussion being a very good estimate of the total discounted net benefits potentially experienced by all qualified users of an area and surrounding areas over a 150 year period. We know we cannot foresee all of the needs and interests and values of future people but we hold that we can see the basic needs. These are potable water, air, rich soil, low noise, moderate temperatures, minimum disease and trauma, vistas, wilderness, readily-available energy, minimum risks from catastrophe, shelter, varied plant and animal life, non-toxic and non-radioactive conditions,and control over pests. We separate private wishes and interests and public interests for we know things will be different tomorrow. We can imagine and plan on and invest in receiving a stream of benefits. We can estimate and plot Q. Q reflects the condition of a system, typically a large land ownership with all regional dependencies. Having received the land from past residents and owners, we perceive it possible to pass it along. We suggest a modest and vague policy of being fair to or maintaining stewardship for future people. If we are going to use-up something, we'll make an off-setting investment.
Schallau(1989:21)and Kaufman (1953:117) expressed the concept of sustaining being managing orderly change rather than a fixed condition...orderly change toward given goals, the good life...in whatever way it is defined. Q, herein, is that definition.
Equilibrium is a dynamic condition perhaps static stability (Botkin and Sobel 1975). A person walking is in equilibrium. There is variability, left and right, but continual (or continuous) motion forward. A sustained system is in equilibrium, stable and continual (within limits). 
Defining those limits is difficult. The sketch suggests the difficulties. A and B are stable, but neither are what most people discuss as stable. C has a threshold and zero rate of change between any 2 points (except one.) D is highly variable and can be argued to be stable for it continues to fluctuate about a specific mean value. Botkin and Sobel(1975) suggest an alternative formulation, that od Markov chains. Within Lasting Forests we prefer the model of figure E for it is continuous or without discernable interruptions and always falls within specified limits ("reasonable variability". The desired value for the system performance is set (the center line) and then, well aware that systems are variable and that even the objectives may be unclear (fuzzy set theory), then limits may be set. As long as the system performance falls within the limits, it is called stable and being sustained. Negative feedback of the manager (using general systems theory) will adjust the system as it nears the outer bounds and re-direct it to the desired measure. There is no premise of a fixed or constant objective, no fixed centerline, no long-term average. The objective, the center line, may be changing. Change is usually gradually made and usually the bounds change little as landowner and citizen objectives change and as information is gathered about the constraints of the future (feedforward).
If I define the desired condition as R* and the actual condition of an ownership as R, then I can express the score for the area as Q = 1.0 - (R-R*)/R*). When there is no difference between R and R*, the numerator is zero and the score is 100. Since R will fluctuate with budgets, storms, and Nature, then Q will also vary. R* may also vary and a perfect R score in a previous period may not match well with the new social needs (or discoveries from wildland research and modeling). We may proceed to change Q by investments. It will fluctuate as in curve E within bounds.
It will fluctuate among areas. As in forest harvest rotations to gain stable wood production, stable production of a variety of benefits can be gotten from a large area (or many small ones) but not the same area. Trying to get constancy within a small area is not possible, certainly not likely given current knowledge of ecology. Systems tend to be more stable globally than locally. This is a matter of perception of scale, the view of the subsystem, e.g., counties have greater instability than do states. Levin (Science 28 Nov 1986) said that ecologist Brian Walker said that there is a big difference between the notion of stability between theoretical ecologists and land managers. Theoreticians use stability in model ecosystems to mean stability in number of species. The number is called richness, the stability of which is called persistence. The manager is usually interested in animal abundance, the stability of which is called constancy. To gain high persistence there must be fluctuations within the individual species, i.e.,low constancy. Abundant ages and different environments are likely to support many different species, thus the more purturbed the system, the more diverse. Botkin and Sobel (1975:644) observed that local and global stability of ecosystems, in both a temporal and spatial sense, cannot be achieved together and short-term stability may lead to long-term instability. It seems unlikely that diversity leads to equilibrium or that very diverse systems are in equilibrium. When richness is used as a performance measure, such a simple criterion is gained by tallying "1" for each species (or taxon) present, one for cardinals, one for condors. It is so simplistic as to be meaningless. As a community matures, it may become unsuitable for a species. This gap may be like that suggested above in the first illustration of lines. Whether a long gap is tolerable or acceptable (for recreationists or others) is a management problem, one of reconciling production, both in time and space, to meet the clients' expectations.
Stability can grow from an embarassingly simple observation that a recognizable system (Margalef (1969:25), Donald (1967:36) and Kowal (1971:175)) can only do three things, increase, stabilize, or decrease. All systems are dynamic; an apparently static system is merely a sample, a point of observation along a continuum. Time or the duration of observation is an essential dimension of any analysis of stability or sustainability.
When systems dynamics are discussed, there is some unit of output in mind unless some simple comparison is being made like "This system is faster than that." In the case of comparing ecosystem dynamics, a unit of great interest is the P/R ratio. The production of biomass (P) to respiration (R) ratio is about 1.0 when an ecosystem is nearing climax. Climax is a condition of long-term relative stability. If a community of plants is growing rapidly (e.g., a pine forest) the P/R ratio is greater than 1.0. In a grazed woodlot the ratio is less than 1.0 and the dynamics are slow. The system will typically "die" unless outside energy, nutrients, or new plants and devices for their protection are brought in by rain, floods, tides, or man. These inputs can be conceived as pulses. Forest leaves are an annual pulse to the forest floor. Dead material (thus respiring) is called detritus ; urban systems have been called detritus communities. Whittaker and Woodwell (1972:152) said:"The steady-state magnitudes of communities seem not to be directly selected for, but to be resultants of processes which tend, by some mode of growth until output and input are equal, to balance themselves." Stability provides a standard for comparing trends and changes and central tendency. It is a numerical construct and probably has no innate worth; it cannot be assumed to be the condition of maximum goodness.
A system's performance can be seen as a deviation from the mean. Difference equations (Patten 1966) can be brought into play from such a concept. Modeling, analyses, and design all can be shaped around a well-developed concept of a stable system. A system with a rate of 0 is a good place to begin; it is almost trivial to proceed to re-develop the system for ± 0.001 or ± 1.0 for stochastic simulation. It is easy for a computer to generate values on either side of stability.
The following are dimensions by which sustainability may be evaluated:
Kowal (1971:176) said: "Stability is a variable which, in order to have any practical meaning, must be operationally defined, i.e. must be associated with a set of instructions on how to measure it. When measureable, measurableodeled for improved understanding. The system may have to be modeled as stochastic. Nature or all of its combined variables is allowed to vary the system responses. We say "explained by stochastic processes" (rather than deterministic processes) when we do not know the cause of variability within the system. Our models within Lasting Forests are mixed, for we do know the nature of some variables. There are infinitely many possible measures of stability, each of them defining a different variable, or concept; there is no such thing as 'real' or 'true' stability any more than there is a 'real green' or 'true short.' One defines stability to suit one's purposes ..."
Smith (1973:105-118, 169-173) described stability prior to evaluating it for Virginia. The dependent variable or ecosystem measure of interest is Y; amplitude is a; the period is T,k-m; the duration is n years; B is the slope the central tendency. Resilience is the ability of a system to recover from a severe perturbation or change. A farmer on a flood plain may have total crop loss in a year but that is likely to be part of his or her calculus of existence and loans, savings, etc. may (and likely will) allow recovery allowing continued cropping on or within the threatened area. Some towns hit by a tornado or earthquake recover; some do not. Ecosystem stability is a complex mathematical formulation, a human perception of the condition of a system. Watt (1973) as well as Whittaker and Woodwell (1972) contended that stability was of the natural order. It is nature's long term best play. Watt (1972) said that it spread the risks. While people may desire advances and improvements, they cannot transcend certain laws. The more unstable a system, the more likely people are to pass a tbreshold -- threshold personal health, social well-being, or human existence. The observation of stability is, however, independent of the use to which it will be put, i. e., the conclusions drawn from the observation. Whether it is desired and achieved, and achieved cost effectively, is the set of questions for those seeking to sustain forests and profits.
See also The Trevey 's section on sustainability.
Literature
Schallau, C.H. 1989. Sustained yield versus community stability:an unfortunate wedding? J. Forestry 87(9): 16-23.
Kaufman, H.F. 1953. Sociology in forestry p113-119 in W.A. Duerr and H.J. Vaux eds.,Research in the economics of forestry,Pack Forest.Foundation, Washington, DC 475pp.
The World Commission on Environment and Development 1987. Our common future, Oxford U. Press, UK
Botkin, D.B. and M.J. Sobel. 1975. Stability in time-varying systems. Amer. Naturalist 109(970)625-646.
Return to the top.
| Quick Access to the Contents of LastingForests.com |
|---|
This Web site is maintained by R. H.
Giles, Jr.
Last revision January 17, 2000.