The principles of ecology lead us to think of having, as a necessary reference point, the structure and functions of an ecosystem in the design of physical territorial systems built by man (technological systems).
The functional unit in the study of the natural environment is the ecosystem. Then we will try to consider in the study of technological systems, to facilitate the analysis, functional units that we will call technosystem. The technosystem can be regarded in the same way as the ecosystem because we can define the functions of production, consumption, and decomposition in both systems.
The similarities between these two environmental systems, natural and technological, are apparent and can be studied and evaluated in the same way because we must not forget that the technosystem is, in fact, itself a part of the ecosystem.
The succession (development) of an ecosystem tends to be a mature ecosystem in which per unit of available energy flow is maintained a constant production of biomass over time (e.g., tropical forests, coral reefs, etc.).
Starting from the predictable characteristics of adaptation and development of a mature ecosystem, we can define in parallel the features that should have a technosystem "mature," considered an "environment where energy flowing in a set of interdependent technological components transforms and recycles the matter.
From the following comparison, we can outline a strategy to choose the appropriate technologies for the natural environment in which the technological environmental systems (technosystems) are organized in a similar way to the biological environmental systems (ecosystems), integrating them into the structure and functioning of nature:
Productive stability
Ecosystem: in mature systems, there is a tendency towards productive stability; energy is used entirely to maintain and control the ecosystem structure. Everything is sized on the constant input of solar energy.
Technosystem: a mature technosystem is sized on the input of energy sources and renewable resources (biomass, sun, wind, etc.).
The production system must reach a condition of "zero growth," at least about the accumulation of the means of production and the resulting products.
The only growth is dedicated to controlling and maintaining the system's quality (energy conservation, energy efficiency, recycling, etc.).
Specialization
Ecosystem: the spatial distribution of the component species of the ecosystem is optimized according to specialization. Each living species has its ecological niche to perform characteristic biological functions adapted to its habitat.
Technosystem: spatial distribution of the activities of the technological system, making use of technologies appropriate to the final purposes to improve the performance of the second order in energy transformations. Therefore, use technologies that must be consistent with the ultimate energy use also qualitatively.
Biodiversity
Ecosystem: species diversity is high. The development of biodiversity, together with the spatial distribution of species, favors the use of land resources, giving rise to a complex system well balanced and stable, with a greater possibility of control.
Technosystem: use of the concept of a watershed that combines natural and cultural attributes. This favors diversified technological solutions, corresponding in scale and geographical distribution to the needs of end-users, thanks to the availability of most natural energy flows. In this way, the energy supply is a set of individual and limited contributions, each of which can ensure the optimum efficiency in defined circumstances concerning the end use (e.g., wind turbines, biofuels, solar panels, photovoltaic cells, fuel cells, etc.)
Material recycling
Ecosystem: mature systems have a greater capacity to retain matter, recycling it through the closure of biogeochemical cycles. Through the decomposition of organic residues, inorganic nutrients are recycled as a supply source for plants. The balance between the speed of production and the speed of decomposition is thus respected.
Technosystem: recycling of waste products, through the separate collection of waste, the recovery or transformation (decomposition) of waste by molecular dissociation, digestion and anaerobic fermentation, composting into co-products (e.g., compost, biogas, hydrogen, methane, ethanol, etc.).
In mature systems, it is necessary to use biodegradable materials that allow the return of residues in the production phase. The process thus tends to cyclicity.
Self-regulation
Ecosystem: if the system is in some way altered from the outside, it tends to modify itself until it reaches a condition of stability through mechanisms of self-regulation (homeostasis). The functions of each organism are integrated concerning the other functions of the ecosystem. Consequently, quality is privileged at the expense of the maximum quantity of products that can be maintained.
Technosystem: using integrated technologies in such a way as to emphasize quality criteria regarding the technosystem as a whole. Integrated technologies make use, on the one hand, of different renewable energy sources and, on the other, of cogeneration systems to improve the efficiency of the various processes (e.g., combined heat and power systems).
Entropy slowdown
Ecosystem: in the mature ecosystem, the degradation of energy with the consequent growth of entropy over time is delayed by the availability of ecological information.
The ecosystem tends to have more available energy in the food webs, using solar energy to produce organic matter. But also other energy flows not strictly solar (wind, tides, etc.) and a whole range of ecological information flows that optimize the use of energy, slowing the dispersion of energy fixed by plants.
Technosystem: the slowing of the growth of entropy is obtained with a system of integrated technologies, using technologies with low energy intensity, sizing the system on the input of energy sources and renewable resources, using in "cascade" the same energy flows to increasing entropy for different users according to the final purposes, also taking into account in land use planning, for the conservation of energy, the existing physical conditions such as climate, land, etc., (e.g., bio-architecture, passive systems).
Self-sufficiency
Ecosystem: the system tends to organize itself in such a way as to provide for all its needs. Its ultimate goal is self-sufficiency to make the best use of all the elements within the system and minimize the exchange of energy and matter with the outside.
Technosystem: a mature technosystem tends towards self-sufficiency by using local energy sources and resources in the best possible way.
In it is privileged the following principle "the optimum efficiency is always less than the maximum efficiency" valid in mature ecosystems. This is justified by the fact that any increase in efficiency regarding production is always at the expense of maintenance and control of the system itself.
In conclusion, we can see from this analogy between ecosystem and technosystem that the critical problem is how man designs and controls the living space by transforming energy and matter while respecting nature. Therefore, to choose technologies appropriate to the natural environment, guided by the principles of ecology, having as objective both energy-saving and healthiness of production processes for a better quality of life.
by Giulio Ripa, written in the 1980 (see the original article in Italian)