Eco-Watch

7/14/94

SPECIAL ECO-WATCH READERS FORUM ON SUSTAINABILITY

=============================================================================== Your chance to cuss and discuss ongoing topics at the interface between ecology and economics -- that is, most anything to do with public lands management. ....... D.Iverson:R04A ===============================================================================

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Topic: "Sustainability Defined" (E-W 7/1/94) For the past several months Zane Cornett (R10F04A) and I have been talking with some of you, trying to work up a definition for sustainability. We settled on one that drew from two key sources: ECOSYSTEM HEALTH, Island Press, 1992 and ECOLOGICAL INTEGRITY AND THE MANAGEMENT OF ECOSYSTEMS, St. Lucie Press, 1993. We are interested in feedback. If you are not so weary of this search for definition and philosophy that you have hit the 'delete' button by now, take a look at what we came up with and let us know if you think we are: (a) crazy, (b) boring academic types who might someday find a life, (c) contributing a wee bit to this ongoing learning process, or (d) none of the above. Dave. +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Feedback, General:

From: Susan Giannettino:R04A
Date: Jul 12,94 8:22 AM

Any effort to contribute to the dialog regarding management of ecological systems adds value to the effort. Two thoughts. you use a phrase that requires definition as much as integrity does...and that is quality of life. Defining that should keep you busy for awhile. and my second comment is that "scale" is critical to thinking about sustainability of ecosystems.... The Colorado Plateau is a system as is the stuff of Mule Canyon... what is sustainable and has integrity at one scale might not at another. just thinking out loud here... ----------------
From: Dennis Murphy:WO Host: W01C
Postmark: Jul 01,94 1:27 PM Delivered: Jul 01,94 11:26 AM

DAVE, ROB MROWKA SHARED YOUR DEFINITION WITH ME AND I WOULD LIKE TO SHARE MY REACTION WITH YOU. KEEP IN MIND THESE THOUGHTS WERE TRIGGERED BY MY PERSONAL BIASES AND VALUES, AND THEY AREN'T REALLY SOLUTIONS OR BETTER IDEAS, JUST THOUGHTS THAT CAME TO MIND AFTER READING YOUR DEFINITIONS:

1--THE PHRASE "ACROSS THE LANDSCAPE" IS BECOMING BOTHERSOME TO ME. I KNOW I USE IT A LOT AS DO A LOT OF OTHER PEOPLE, BUT IT INTRODUCES A LOT OF AMBIGUITY. IT ALSO IMPLIES THE ONLY ECOSYSTEMS THAT EXIST ARE AT THE LANDSCAPE LEVEL WHICH IS NOT NECESSARILY TRUE.

2--ANOTHER IMPLICATION WE ALWAYS SEEM TO MAKE IS THAT "ALL" ECOSYSTEMS ARE VERY COMPLEX. THIS AGAIN MAY BE GENERALLY ACCURATE, BUT THERE MAY ALSO BE SOME RELATIVELY SIMPLE ECOSYSTEMS THAT ARE NOT TERRIBLY DIVERSE, BUT STILL VERY IMPORTANT TO SUSTAINABILITY.

3--IT WOULD BE HELPFUL TO ME AND MANY OTHERS IF THE VERY TECHNICAL DEFINITIONS COULD BE PARAPHRASED OR DEFINED BY EXAMPLES IN SIMPLER TERMS TO HELP PEOPLE RELATE BACK TO THE TECHNICAL DEFINITION. HAVING WORKED ON A COUPLE DIFFERENT TERMINOLOGY EFFORTS AS OF LATE I KNOW HOW HARD IT IS TO COVER THE SPECTRUM AND STILL MAINTAIN THE CONCISE SIMPLICITY NEEDED TO COMMUNICATE THE MEANING OF TERMS. GOOD

LUCK IN YOUR EFFORT. DENNIS
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From: Kailash Chandra Govil/
internet(b)nature.Berkeley.EDU(b)kailash/
Hi.

Axiom of attempt to understand: Any attempt to understand is better than not to attempt. May like to consider two more axioms for defining sustainability:

Axiom of scale and level: Conditions for and characteristics of a phemomenon may vary at different scales and levels.

Axiom of dimensions: Conditions for and characteristics of a phenomenon may vary across different dimensions (time, space etc.).

Therefore, definition and its context varies across dimensions, scale and level. With best wishes. Kailash.
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From: Wayne R. Owen:R04F02A
Date: Jun 30,94 5:02 PM

I think that the FS has a fear of academia in general and most folks around here anyway find that if they have to think about something then it is too much effort... /wo/
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From: Monica Schwalbach:R04A
Date: Jul 04,94 4:06 PM

Good job at attempting to define such a difficult concept! A couple of parts are still fuzzy, however: First, how is "quality of life" defined? Whose quality of life will be continued in managing for sustainability? Also, for systems integrity are we striving to maintain all their complexity? or sufficient representation of components and processes to maintain options (capacity for self-renewal)? The answers to these questions can have major implications for management (and can point us toward our broader responsibilities as members of the Global community).
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Feedback, Quality of Life:

From: MARIETTA DAVENPORT:R03F04A
Date: Jul 01,94 8:53 AM
AT LEAST YOU ARE TRYING TO COME UP WITH SOMETHING. BUT HOW DOES ONE DEFINE QUALITY OF LIFE AS OPPOSED TO MERE EXISTENCE, WHICH IS WHAT SOME OF THE RESOURCES ON THE FOREST ARE UP AGAINST RIGHT NOW - MERELY SURVIVING?
From: Kathy E. Sleavin:W04A
Date: Jun 30,94 4:29 PM

..... a part of your definition referred to "quality of life", yet that term was never defined. Who is to determine what is "quality"? Is it 40 acres and a mule for each family? Is it living in apartments stacked on each other like NY city or Calcutta? It seams to me that if you develop a definition for "sustainability" you had better not have any undefined terms like "quality of life". I appluad your effort, but a definition should not contain undefined terms.
From: Dave Iverson:R04A
Date: Jun 30,94 4:59 PM

There is an article in Environmental Values 1(1), 1992, by Sir Crispin Tickell titled "The Quality of Life: What Quality? Whose Life?." Those two questions will certainly need much more discussion if our version of sustainability is to gain some acceptance. I'm not inclined to believe that a once and for all definition will do. But I do agree with Tickell that we need to "change the topic of conversation" from consumption, production, growth, etc. to what might constitute "quality of life." Thanks for kicking this discussion off.. As to who will decide what quality of life means, that too is up for grabs. But in the framework for ecosystem management that I like best it says: People want direct involvement in decisionmaking. Then later it says: ecosystem management means opening up our decisionmaking to all interested people. d.
Feedback, "Scientific Fog:"
From: Ingersoll, Jerry:R04F17D05A
Date: Jun 30,94 6:33 PM

What you've written is unarguable, and definitely contributes to the discussion of EM. However, it's written in academic terms - the "fog index" is pretty high. It would sure be nice if we could write something in soaring prose like Leopold's:
How about:

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> From: Rob Holmes:W01B
Date: Jul 01,94 8:09 AM

Expositions like this are useful and necessary to continue to advance the frontiers of our knowledge and professionalism. At the same time, we should recognize that the vast majority of people relate to the concepts better at the level of the "goose that lays the golden eggs", as JWT described it to an uncertain Congressperson. Guess I'm saying, the treatises that read like PhD dissertations are fine for a certain audience, but, perhaps even more important is to find ways to communicate the ideas in simple, lay terms.
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From: Betsy Rickards:R04A
Date: Jul 01,94 8:33 AM

..... remembering some earlier drafts of this, I say you're there -- I get it. In thinking about our sound-byte and commercial driven society, I can't help but think the definition needs to be simpler...perhaps even like the Energizer bunny, sustainability means ecosystems keep going and going...corny, but more people would get the message...
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From: Rob D. Mrowka:WO
Date: Jul 01,94 9:11 AM

Dave, I like the definition, but I think it is rather abstract and oblique for most people who have to do it! In an academic context it is good, and I will likely use the thoughts, but I think we need something simplier for day-to-day. For instance, the term "self-organizing systems" will send most folks headed for the "5 NL" keys! * Rob

From: Jim Culbert:WO
Date: Jul 01,94 9:13 AM

I think this is awful! It is far too abstract, using terms way too complex for the person in the street to understand. It also requires a definition of integrity, just to form a definition of sustainability. Until we can bring the understanding of sustainability to a level shared by the majority, the search for a unifying definition is merely an academic exercise. I am not on the network on which this was presented. Please share my reactions with the authors. I wish I had time to try and translate their work into terms useful to the "common man", but I do not. Thanks for sharing! Jim
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From: WILLIAM F. PELL:R08F09A
Date: Jul 04,94 6:20 PM

................. I think your definition of sustainability suffers from wordiness AND reliance on an extraordinarily VARIABLE (not to mention difficult-to-define-in-and-of-itself) quality-- quality of life for humans! I suggest a modest revision: Sustainability is a relationship between dynamic cultural, economic, and biophysical systems in which human uses and activities do not threaten or damage ecological integrity (across landscapes and over the long term).

On the other hand, I wonder why you saw fit to try to improve on Norton's (1992) definition in the first place? Seems all you've added is the idea of cultural systems, which is fine, but Norton's could be modified with "and cultural" and achieve the same thing. I think his ideas about integrity may be more clearly stated as well.

Again, fewer words would work better: An ecosystem has integrity if it retains its complexity and capacity for self-organization over time (diversity is implied by complexity; using self-organization twice leads you close to tautology)! Good effort guys, and thanks for stimulating thoughts. BP
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From: John Francis:R12A
Date: Jul 05,94 7:37 AM
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NOTE FROM IVERSON: Conversation on this matter prompted me to dig out Laura Westra's book AN ENVIRONMENTAL PROPOSAL FOR ETHICS: THE PRINCIPLE OF INTEGRITY, 1994. This book is wonderful on sustainability, ecological integrity, and more.
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Feedback, Ecological Integrity:

From: DAVID BRAYTON KITTREDGE JR:X400
From: C=US/ADMD=ATTMAIL/ORG=ATTMAIL/PN=DAVID JR/ DD.ID=internet(b)forwild.umass.edu(b)dbk/

......... thanks for sharing the ideas on EM ecosystem integrity [EI?], and sustainability. to me, it all boils down to EI. if ecosystems are functioning well and normally, and hence have integrity, then probably whatever you are doing in them will be sustainable. i suppose you could say that an ecosystem could be a little out of whack,but still functioning more-or-less normally, [firing on 5 out of 6 cylinders?], and the activities therein might not be sustainable... lo, the need to know more about how far out-of-whack we can take a system... and how/if they can rebound...

in any event, thinking about ecosystems in terms of their INTEGRITY is vastly superior to thnking about them in terms of their MANAGEMENT. ESPECIALLY WHEN IT COMES TO LANDSCAPES LIKE OURS IN NEW ENGLAND, WHERE THOUSANDS OF INDIVIDUALS OWN IT ALL, NOT THE FEDS. "Management" has that "command-and-control" connotation that scares private landowners, and sends them running in the direction of the wise use gang. I believe it was at the root of the noisy opposition within SAF to the now famous [Society of American Foresters] Task Force Report. We will all be better served by thinking ablout the issue in terms of ecosystems- their function and integrity, rather than their management... unless I suppose someone owns the entire ecosystem... which is the case out west with the feds...

Finally, who cooked up the phrase "ecosystem management" anyway? In my opinion, that M-word doomed it to stiff opposition. Don't get me wrong, I embrace fully the Task Force Report and the concept, and am trying to promote it actively to foresters and landowners as a concept or philosophy here in New England. But it would be alot easier to do without the "management" connotation. cheers, dave

David B. Kittredge, Jr. Extension Forester/Associate Professor Department of Forestry & Wildlife Management
Holdsworth Hall, University of Massachusetts
Amherst, Massachusetts 01003
413 545-2943 413 545-4358 fax [email protected]
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Feedback, Integrity versus Health:

From: Sharon Friedman:W01C
Date: Jul 05,94 12:08 PM

I dislike the whole idea of introducing another concept (eco integrity) to the product mix. In the Woodley, Kay and Francis book they say that integrity is more than health because when they have integrity they can attain and maintain an optimum operating point when stressed, and that integrity involves the ability to continue evolving and developing. The health definition in Costanza did all that for me. In fact, "integrity" has definitions which include "complete" and "unimpaired" not to speak of "upright, honest and sincere". Do these evoke dynamism and evolution? NOT TO ME. Also there is no "optimum operating point", there are many possible operating points, some of which people prefer and some which they don't. Health is a simple and powerful concept which everyone can relate to. Integrity is something else and I question the added value of using it. So now we can have books about criteria for "health" criteria for "sustainability" and criteria for "integrity" with substantial overlap in content. We know we have to figure out what makes an ecosystem healthy. Does talking about integrity distract us from this effort or add in some way?


Feedback, Anthropocentricism v. Biocentricism:

From: Richard G. Krebill:S22A
Date: Jul 01,94 7:55 AM

....... its good if you are a people person. I personally think sustainability can exist with or without people in the equation though. Yours is good from perspective of communicating where you are coming from. You are trying too hard though from the respect of representing universal understanding (and that's probably a grossly idealistic thought on my part).
BR> ------------------------------------------------------------------
From: JOHN L. NELSON:R03F04A
Date: Jul 01,94 8:26 AM

Thanks, this reflects a lot of thought and work, and is pretty close to what I would like to say in my less-sophisticated way. I must confess continuing general uncomfortableness with what I perceive as a too-anthropocentric view of things - e.g. linking sustainability to human comfort (if you will) in the definition, yet speaking of all other life only in the most general terms when defining sustainability or ecosystem health. I mean, I think I understand you don't mean it that way, but does everyone else? Anyway, thanks for the continuing effort - it IS appreciated.


Feedback, Humans in Ecosystems:

From: Gail C. Tunberg:R03F10A
Date: Jul 01,94 9:16 AM

Can you back up with me a few steps, you have identified cultural and economic separate. Maybe it is the lumper in me, but isn't economics a function of culture?

From: Richard Fairbanks:R06F18A
Date: Jul 01,94 8:45 AM

The sustainability definition is excellent. Ecosystem integrity definition is intriguing. When I apply your definition of sustainability to Western Oregon's declining rural employment, rapid in-migration/suburbanization and several other problems, I come up with an observation about sustainability in relation to change. Sometimes it is not the change itself that creates social/economic problems, it is that the rate of change overwhelms the coping mechanisms of communities and individuals. If the town knows for five years or so that the mill is going to run out of logs, adaptation seems to be relatively painless. If they go to work one morning and the layoff notice is waiting for them, the shocks seems to disrupt the community far more than a gradual transition. The point is (if there is a point) that if we want sustainable communities, we need social/economic/governmental systems that can change in the face of new conditions.
From: Zane J Cornett:
Date: Jul 01,94 8:38 AM

Nice -- someone picked up the part about the sustainability definition fitting the social/cultural and economic systems too -- AND saw an immediate application. THAT makes a lot of the work we did move beyond fun into productive...

I wonder if Leopold thought in academic/technical temrs to get things clear in his mind and then translated that into poetic prose after he REALLY understood it -- Or was he truly a sage who thought and saw things so clearly that the middle step was unnecessary. Sigh. Once in a very long while I can do the latter...

Then again, when one tries to define (for those that ask for definitions so that they can apply philosophy on the ground) something like "tends to be right when it ..." those complex subjects that are addressed poetically in simple terms seem to allude definition in the same simple terms. As I told you yesterday, I believe our definition is more simple than Norton's and Kay's. Oh well, something to ponder. Maybe I'll climb to a mountain top this weekend and see if I can connect with Aldo.
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From: Dick Artley:R01F17A
Postmark: Jul 01,94 11:55 AM

Dave and Zane:

I appreciate you sending out your proposed definition of sustainability over the Eco-Watch network for review and comment. The topic is certainly timely.

Webster defines sustain as: to maintain, keep in existance, keep going, prolong.

We have correctly defined the ecosystem to include humans....their needs, their activity, their influence and their impacts. To define an ecosystem with humans excluded would be folly. Where we get into trouble is when we attempt to define sustainability in the context of this all-encompassing definition of the ecosystem. Why? Because the ecosystem as currently defined, is not sustainable in terms of the continuation of expected, customary quality of human life.

Things are not in equlibrium. We have a world population thats increasing in a world with a finite landbase and limited resources. Many of the resources being used up are non-renewable or at best, renewable over long timeframes. Consumptive demands increase daily. Something has to give. Tradeoffs must be made. We could potentially form a sustainable, symbiotic relationship with the renewable resources, if we manage right and if consumptive demand levels off. However, with the increases in population, we will soon approach a point where we strain our ability to sustain even the renewable resources. The other part of the equation revolves around our parasitic relationship to non-renewable resources. This use pattern is not sustainable, however it can be prolonged by increased efforts in recycling.

For simplicity, lets define the ecosystem as a car, a human driver and one gallon of gas. How would we write a definition of sustainability for this system? What happens when we apply your proposed definition? Lets assume that relatively unrestricted travel is a requirement for the driver to "continue his/her quality of life". When they drive, they will eventually use up the gas. Even if we assumed that the gas was renewable (replenished in a trickle) over the long term, the driver would have to drive very slowly or short distances...then wait. My point here is that to sustain, maintain and prolong this system, the human use must be constrained. Historic use patterns must be modified and changed. Accepting constraints on human use must not be confused with eliminating the human factor in the ecosystem. It really all comes down to where we as a society have the most flexibility...the human side or the biophysical side.

There is an answer. Society must evolve and redefine quality of life under these constrained conditions. If given the alternative of continued, unsustained resource use for short term gains vs. accepting a little less as being OK, I'll bet society will choose the latter. Sustaining the biophysical system will require constraint on the human consumptive use...this would include limits on recreational use as well as commodity outputs. Before long, this constrained use level would become the norm. The most difficult time is during the transition. We are in this transition now. This notion must be clearly pointed out in any definition of sustainability or ecosystem management. This has been lacking so far.

It is inevitable that we will be forced to make value judgements as we implement ecosystem management in a sustainable way. What do we do when we face the situation where a 1 unit increase in human use (ie. 1 job, 1 RVD, 1 AUM) results in a 1 unit decrease in biophysical ecosystem integrity? Using your definition would we "threaten the integrity of the system" or "discontinue the quality of life for one human" for the person whose job is on the line? Remember the finite landbase and increasing population? To me the answer is clear. As I said before, we can not do it all anymore. Tough decisions will have to be made. Any definition of ecosystem sustainability must address this contingency. Dick Artley
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From: Rai Behnert:R10A
Date: Jul 06,94 9:00 AM

... I like the way you deal with human activity in these definitions. I also continue to think we should use the phrase Ecosystem Use Management instead of Ecosystem Management to focus attention on our influence on ecosystems and our ability to choose to use them in sustainable ways. The latter phrase seems to imply we humans are somehow in charge of them.

From: TOM QUINN:R03F05D05A
Date: Jul 07,94 8:36 AM
... the definitions you propose are definitely on the "right" track....at least from my perspective. Too often, the "humans are an important part of the ecosystem" argument is used to rationalize past and present abuses; whereas some could argue that indeed humans are an integral part OF the system only so long as we play a role in sustaining the integrity of the system...otherwise we become an external disruption TO the system (a temporary aberration in geologic time). And you are correct that any definition relies on one's interpretation of "integrity", which is where the differences of opinion generally arise.
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From: Arnold G. Holden:R6/PNW
Postmark: Jul 07,94 9:28 AM

Comments on the definition of sustainability: a) it's too pedantic--any definition of sustainability worth its salt has to be accessible, understandable, and meaningful to a wide range of people including just plain ole citizens, and b) it's not very helpful given where we as a society are with regard to social, environmental, economic, and geographic development. What about agriculture--the great breadbasket across the middle part of our country. Ag lands should be managed sustainably, and their ecosystem complexity and self-organization are basically gone. Transportation systems should be managed sustainably. Cities should be managed sustainably.

From: Susan Sater:R06C
Date: Jul 08,94 4:07 PM

I like this work--but I think including both the terms "cultural" and "economic" in your definition is redundant. I'd stick with cultural and drop economic (I think economic factors/forces are a function of culture).
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Feedback, Self-Organizing Systems:

From: James Schmidt:R05F16A
Date: Jul 05,94 9:34 AM

You might include a definition of "self-organization" as well.
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From: Marla Lacayo-Emery:S24A
Date: Jul 05,94 2:18 PM

..................... Could you give us a little more about the concept of self-organizing? Thanks, Marla
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From: Shannon L. Downey:R05F11D51A
Date: Jul 07,94 2:54 PM

I'm a little confused by the concept of "self-organizing" as an indication of health. It seems to me ecosystems are always self-organized (even the ones we try to take over, such as cities or intensively managed monocultures). The system just functions at a higher or lower level, and is more or less dynamically complex (sensu Senge in "The Fifth Discipline" (1990). To me healthy just means fully functioning, and sustainable just means something that can keep happening indefinitely without impairing health. For instance, I can go one night with only 4 hours sleep without seriously impairing my health, but if I try to do that every night, I quickly get sick - i.e. it's not sustainable. Same with drinking lots of alcohol, etc. Of course, what's sustainable for me now, may not be in 40 years, or may not be for someone else now. Same goes for an ecosystem...

The axiom of differential fragility needs fine-tuning. Different ecosystems have differential fragility to DIFFERENT disturbances - human-caused or otherwise. A desert may show great resilience to drought or fire, and great fragility to bulldozers (i.e. return slowly, if at all to it's predisturbance complexity and function).

And some ecosytems, like eastside pine, become unhealthy with too much rest - again, sorta like people! - Shannon
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From: Mark_Shasby_(AFO):X400
Date: Jun 30,94 8:28 PM
internet(b)vector.wr.usgs.gov(b)shasby/

A very interesting topic/subject that i request more time to think about and comment on. Its very close to my heart, this issue. My initial reaction or the one thing I saw missing the first time through is the recognition of the natural process of evolution that ecosystems are going through. Every ecosystem is going somewhere. Theoretically towards some sort of climax, but definately not a static position. Perhaps Norton needs an axiom on the dynamic nature of ecosystems and the fact that they are moving, evolving in response to internal and external factors. (the fishbowl). We, as land managers tend to manipulate the ecosystem to serve us by holding it in a state of its evolution that is productive for us. HOw we define productive is a big issue. Fiber/biodiversity/food/aesthetics/"natural". So, if we really want to preserve ecosystem integrity, do we want to preserve an ecosystems natural inclinations to become something different, ie, allow evolution of the system and its components to take place. Man is a part of all ecosystems now for better or worse. Our impacts are real. We alter the rate and the direction of change. Recognizing the vectors and deltas is as important as the objects.

Global change is a given. Ecosystem change/evolution is a given. Species change/evolution is a given. Its all a big circle, or better yet, a rolling ball. The question is where is it going, how fast is it going, and can we do anything to direct it towards something that will allow us to survive as a species? Do we want to go in that direction? Are we kidding ourselves in believing that we are the ultimate life form and that the entire planet must be directed towards our survival? Do you suppose that if the dinosaurs had started a global change/ecosystem management program that they would still be around today? Are humans the ultimate indicator species? I kinda think at times that maybe we are a bit genetically deficient. Look at Rwanda.

Kinda got off on tangent here eh? Oh well, I'll think about it a bit and get back to you. I don't think you can ignore the issue of evolution and change though. They are they only thing we know will happen for sure, in spite of what we think we can do.
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Feedback: How do we make it real?

From: Pete Karp:R04F18A
Date: Jul 03,94 12:24 PM

The theory sounds just fine. What I don't read is what this means to me as a person responsible for "managing" one or more ecosystems associated with the Uinta and Wasatch-Cache NF's. It doesn't mean anything in REAL terms to me. Maybe that's just the evolution of the definition that must occur over time?????

From: Bradley G. Smith:R06F08a
Date: Jul 07,94 3:22 PM

I suppose the big question now is: how do I measure integrity? Integrity needs to be measured or assessed somehow to detect trends and changes. Otherwise sustainibility cannot be assessed.

. I am somewhat dismayed that "ecosystem" is being redefined as an integration of biophysical, cultural, and economic systems. Ecosystem management or, preferably, an ecological approach to management does indeed integrate these systems. From an ecological perspective however an ecological system (ecosystem) is a set of organisms, their environment, and the fluxes of energy and matter between them at some (arbitrarily) defined spatial and temporal scale.

. Jim MacMahon at Utah State University would say in his ecology 101 (and graduate level classes) that ecosystems do not have functions. Ecosystems are functioning, i.e. flows of energy and matter between components are present. To some extent this is semantics. On the other hand it is a clear distinction. To say that an ecosystem has functions implies that it is a "unit" or "organism" endowed with purpose. Ecosystems are constructs of our mind that are useful mechanisms for understanding the world we live in.
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Feedback, Role of Energy:

From: Ariel Lugo:R12A
Postmark: Jul 03,94 1:41 PM

You do a good job of defining sustainability, but ignore the fact that sustainability is a function of energy availability to maintain a given level of human activity and life quality; and thus, the fossil fuel based civilization is not sustainable on the long run. But the concept as you describe it can be sustained as long as energy inputs are available. A more serious problem is caused by the definition of ecosystem integrity. The capacity of self-organization is intrinsic to life; ecosystems don't lose this capacity, no matter what we do. The only problem is that we may not like or be able to use the products of self organization of highly impacted regions of the world! It would be nice to discuss these things, but its hard for me to write a dissertation on the subject! Perhaps our paths will cross in a meeting someday.