No 176 Posted by fw, May 19, 2011
Resilience and sustainability are two key terms that are frequently undefined, poorly defined or misunderstood, especially by the public, in popular writings about social-ecological systems. So one more explanation of resilience is probably not a bad idea. Therefore, without apology, here is a video-based explanation of resilience, titled: The best explanation to (sic) resilience. Whether or not it’s the “best explanation” is for you to judge. Personally, I found it enhanced my understanding, although an example of a complex social-ecological system would have been a bonus. A transcript follows the clip.
But first, a note about the presenter: Brian H. Walker is an internationally experienced scientist working on ecological sustainability and resilience in social-ecological systems. He earned his PhD in Plant Ecology from the University of Saskatchewan, in Canada in 1968. He has also made significant contributions to global change science, serving as the Chair of the Scientific Steering Committee of the IGBP core project on Global Change and Terrestrial Ecosystem, from 1990–1997. He is now a Research Fellow with the Commonwealth Scientific and Industrial Research Organisation (CSIRO), Australia’s national science agency Sustainable Ecosystems and is also Program Director and Chair of the Board of the Resilience Alliance, an international research group working on sustainability of social-ecological systems.
How much can you change without losing your identity, before you become a different kind of person? How much can a city change before it becomes a different kind of city? Or a forest? How much can you change a forest before it starts to function and to look like a different kind of forest? All of those questions are about resilience? And what I want to do is explain a little bit about the basis of resilience. And it all has to do with the notion of self-organization.
Self-organizing systems are self-maintaining – within limits
All those systems, because that’s what they were, are self-organizing systems. Your body is a self-organizing system. You maintain a constant temperature of about 38 degrees centigrade (38C). If you go up a bit and you get hot, your body starts to sweat, and you evaporate to cool and your body temperature comes down. If your body temperature goes down, you shiver and your muscles vibrate and your body temperature goes up.
Resilience is about how systems maintain their self-organizing capacities
But there are limits to that. And there are limits to how much everything can change. And that’s what resilience is all about. It’s how do you maintain the self-organizing capacity or ability of a system. And let me explain it by again coming back to the body. And what I’m going to do is describe some work of a colleague of mine. He’s a professor of trauma surgery in Washington University, in Louisiana, Tim Buckman. And he gets people into his surgery who are just about dead. They’ve been shot and mangled in accidents, and he has some terrifying pictures of people who have half their live shot away, most of their blood gone – almost dead. And I’m going to use them as a metaphore, a little analogy that scientists use to explain resilience and self-organizing.
Self-organizing systems change but tend to return to a state of equilibrium
And it’s [the metaphor] about a bowl or a ball in a basin. And what it is [drawing on the whiteboard] – this is a system. And this is how much you can change. This is your body temperature or this is how much a forest can change. And if the body – if you put it up there – what it is [draws the ball high up on the right inside of the basin] – it will change the system, it will tend to come back down to this equilibrium point. If you put it up there [up on the left inside of the basin] it will tend to come back to the equilibrium point.
Systems that cross boundaries seek new equilibrium points or, depending on the type of system, may collapse and die
But there are limits. And if you go over the limit [draws an overflow extension of the upper right edge of the bowl] and the ball ends up there [over the limit] then it goes down into something else and goes to a different kind of a system.
Human trauma victims are systems in a suspended state of self-organization trapped between life and death
Well, coming back to Tim and his trauma surgery, he – from what I understand of his work – said that he gets people who are in what he calls the “Death basin of attraction”. This is the “Live basin of attraction”. [See image]. And he gets people in about here [Draws ball just over the limit of the Life basin, on upper downside of the Death basin]. So they’re not dead yet. They haven’t reached the “attractor”, as it’s called, of this basin of attraction. But they’re on their way. And unless something is done quickly, they die.
And so when they come in to a trauma surgery, the body is stabilized. They hook them up to put blood in, to maintain the temperature, to keep the respiration up, to keep the blood PH constant, all sorts of things. The body is hooked up to a bunch of wires and stabilizers. In effect, what’s he’s doing is he creates a temporary basin of attraction, which is an artificial one, and he maintains it, but it stops the person dying. And then they sit and wait and watch to see what happens. And sometimes, what happens is that this one begins to change, and erode, and go down. And when it does, the body recovers, self-organizes, and it’s alive. Unfortunately, all too often, what happens is it’s this one [the downward slope of the Death Basin] that erodes and then the person dies.
The traumatized rat experiment: Which group will do better – Stabilized control group or experimental group allowed to vary and self-organize?
Now Tim is good observer. And he noticed that when the body is in this suspended state [between life and death], it’s constantly trying to change. The body temperature’s trying to drop, or the respiration trying to go up. And so he wondered, and he got a bunch of rats and he did an experiment with them. And he anaesthetized them to do it properly and carefully. And half the rats – he subjected these rats to the same kind of trauma – half the liver gone, most of the blood out and everything else. And then he stabilized them using the same protocols. And for half the rats he kept them exactly according to the [stabilizing] protocols. But for the other half, if the bodies tried to change, if the temperature began to drop, or the respiration went up, he let it go up, he let the temperature drop, until just at the point of death. But basically, he let the body vary the way it wanted to. And the result was amazing – a significant increase in the survival rate of the rats who were allowed to vary.
The best way to maintain resilience of a system is to allow it to vary, to probe but not cross its boundaries
And so the important message out of that was that the way you maintain the resilience of a system is by allowing it to probe its boundaries. If you never burn a forest, the species in that forest that are capable of putting up with fire, eventually get out-competed and they disappear. The only way to make a forest resilient to fire is to burn it.
If you keep children inside and away from dirt, eating it and getting dust, they become very prone to all sorts of diseases and asthma. The only way to keep children resilient to the environment that they live in is to expose them to it and to disturb them in that environment. So it’s all about – resilience is maintained by disturbing and probing the boundaries of resilience. Otherwise, these basins tend to get smaller and smaller. And we don’t want that to happen.
So that’s the message of resilience. I’ll come back quickly to your own body and the temperature one that I talked about. Why is that you maintain a temperature of 38 – very close to death? If you go over 41 you’re dead. The reason is the earlier models of us hominids, who maybe kept at 35 or 36 degrees, they weren’t as efficient as us so we out-competed them. They’re in the hominid records in the archaeology back there. But we’ve had 10 million years of mammalian evolution to develop the feedbacks, physiologically and behavioural, that stopped us going over that 41. Not always – some old people and some babies die. But generally speaking, humans don’t cross that boundary. So what is it that prevents that? There are a whole bunch of feedbacks—physiological ones of the sort I’ve told you. And they worked.
Now, the essence of resilience in ecosystems, in agricultural systems, is to understand the feedbacks that keep it self-organizing in a way that we want it to.