The increase of entropy on earth as a whole is reversed only because of the existence of a complex biosphere powered primarily by solar radiation, which represents the main source of work and inflow of exergy. After most of this exergy is reflected back into space, some of it is transformed by plants and organisms into chemical exergy and some of it eventually ends up buried as low entropy stocks of carbon, coal, oil and gas. Flows of energy on earth are part of an open cycle; solar exergy comes in and heat goes out. Flows of matter on the other hand are part of a closed cycle (Boulding 1966). Ecosystems are driven by high-exergy and lowentropy resources, and generate almost no waste. In contrast, engineered systems are driven by the extraction of low-exergy resources. At the other end, they produce, accumulate and dispose high-entropy emissions and waste (Nielsen 2007). This flow of energy and matter from ecological sources through the economy and back to ecological sinks has been referred to as “throughput” (Daly and Townsend 1993).
The distinction between natural and engineered systems does not mean that the former are purely frugal and cyclical, or that the latter are purely wasteful and linear. Many industries rely on the recycling of matter and energy from production processes and from consumption wastes. At the same time, the biosphere “dumps” carbon, coal, oil and gas in natural landfills (Jensen et al. 2011). While it is therefore wrong to set natural and engineered systems on opposite sides of a spectrum, there are nevertheless important differences. Nielsen and Müller (2009) argue that in natural systems, the cycles are local, decentralized and develop towards being increasingly closed with decreasing emissions and waste as a consequence. In engineered systems, however, the cycles are increasingly global, transport-intensive and have evolved to be open with increasing emissions and waste as a consequence. Waste control generally reduces profitability; costs therefore tend to be externalised.
Bill Mollison says:
When the needs of a system cannot be met from within itself, we pay the price in energy and pollution.
A permaculture system is a natural system, it's interwoven with nature. While an industrial system is engineered, wasteful and linear.
Of course, there are grades between linear and circular systems. But using permaculture design methodology you come as close to a natural system as possible. To establish small permaculture systems within the industrial system is of course a good thing to do. By time these small increments may take over, as the industrial civilization declines.
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| It's important to look for cracks in the industrial system where permaculture might be introduced |
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