Sunday, January 15, 2012

Self-Contained Communities

by Richard Crews
Can a community be self-contained? In other words, if a "town" were built deep in a subterranean bunker, or on a large ship that stayed at sea indefinitely, or on an isolated island, or on a space station, or in a super-dome on the Moon, to what extent could it be truly self-sufficient? Or would such a "town" always be dependent in some ways on interaction and interchange with a broader environment or world community?

Let us say first that we are talking about a time frame of a few years up to a few decades.

And let us consider several different parameters and the self-containment problems they pose. Specifically, first let us consider the community's needs for such basic "commodities" as (1) energy,
(2) water, and
(3) food;
then its more subtle--even abstract--needs for
(4) cultural stimulation (and cultural diversity),
(5) biological diversity (from genetic to ecological), and
(6) technological support (including innovation).

(1) The problem of energy self-containment is a crucial one. The community needs energy at least for heat (and/or cooling), protection from the elements, and processing of food, water, and nutrients. But it also needs energy for transportation, communication, entertainment, and a parade of labor-saving devices--in fact, having adequate energy is directly related to the overall quality of life--the extent to which life is harsh and tedious or comfortable and varied.

The problem of energy self-containment is crucial to the lifestyle, even to the survival, of the community, but it is not a difficult one to solve. In some settings sunlight, wind, waves, falling water, or underlying environmental heat (such as geothermal or ocean-thermal energy) can provide adequate energy for the community. Although these are not technically intrinsic to or self-contained within the community, let us consider them allowable to solve our energy needs when they are available. And when they are not available, a small-to-medium-size nuclear power source using Thorium or other radioactive fuel can be safe and non-contaminating, and provide boundless energy over a period of several years or a few decades. And although it may be expensive to set up, it requires no ongoing maintenance.

(2) The problem of water depends on two factors: recycling and purification. If one assumes that no water is added to the system (for example, from rain), then one must collect and reuse all water used for drinking, cooking, cleaning, irrigation, etc. This requires some effort and ingenuity. It also requires adequate energy for purifying and transporting the water. But it is entirely feasible.

(3) Providing good nutrition for the people and animals in the community is a complicated and difficult problem. Our nutritional needs are generally considered under two categories, MACROnutrients and MICROnutrients. Macro-(or "large")-nutrients are chemicals that are consumed by the body--they are destroyed or used up in biological processes, and are therefore needed in quantity ranges of tens-of-grams (several ounces) each day.

The three categories of macronutrients are carbohydrates (sugars and starches), lipids (fats and oils), and proteins (composed of amino acids). These have a variety of crucial metabolic functions; to some extent they can substitute for one another (for example, many forms of sugars are interconvertible in the body, and although fats, and after them, carbohydrates, normally provide the main sources of body fuel, any of the three can be "burned" for metabolic energy if necessary). But some are termed "essential": they cannot be synthesized in the body or converted from other nutrients, and the body cannot survive for long without them.

Another substance which is technically a macronutrient but is often overlooked or ignored is the indigestible bulk or fiber needed to carry foods through the digestive track and make our bowels run smoothly. Oxygen and water are also technically macronutrients since we need them in relatively large quantities and "use them up" in the functioning of our metabolic chemical processes.

Micro-(or "small")-nutrients are chemicals that are not consumed or used up in body processes (although tiny traces may be lost through excretion or inadvertently destroyed). They are catalysts that make certain chemical reactions go smoothly. They are needed in tiny, replacement quantities of a few milligrams (pin-head-size amounts) each day.

Micronutrients fall into two categories: vitamins and minerals. There are dozens of essential micronutrients; their chemical reactions and physiological functions in the body are numerous and complex. However, they are generally available in adequate amounts in a varied, natural diet, so if our community has enough varied, natural food to eat, we do not need to worry about providing micronutrients.

On the other hand, our community must grow enough foods to provide macronutrients--especially carbohydrates or lipids (for providing energy), and proteins (for building and repairing body tissues, and to make a million varied enzymes needed for functions throughout the body). Good sources of protein are cattle and poultry (including milk and eggs), fish, and certain vegetables such as nuts and beans. Good sources of carbohydrates are fruits and grains. Lipids are found here and there throughout both animal and plant food sources.

Although it can require complicated calculations to assure adequate nutrition for the community, suffice it to say--as a broad generalization--that a half acre of land under intense cultivation (or several square meters of hydroponics beds), and a few farm animals or chickens or a fish pond (or several cubic meters of fish tanks) per person, with careful planning and maintenance, will suffice.

In addition to the community's needs for energy, water, and food which can be met in reasonable, sustainable, more or less self-contained ways, there are other requirements, perhaps more subtle and even abstract, which cannot.

(4) Cultural stimulation and cultural diversity simply require more than a handful or a few dozen dedicated--but isolated--individuals. The community can have books, videos, performers, and teachers, but over a period of several years or more, the hunger for contact with a broader human community is likely to become intractable.

(5) Similarly, biological diversity (from genetic to ecological) is a deep, persistent requirement for human health and life.

(6) And technological support including innovation is an inescapable hallmark of civilization. We cannot improve or even repair for long the parade of gadgetry that is is essential to our communications, entertainment, transportation, and other mental stimulation without access to and interaction with a broad civilization.

Summary: A community of a few dozen or even a few score individuals, with careful and sophisticated planning and diligent implementation, can sustain itself in isolation for many years in terms of energy needs, water, and nutrition. But in terms of cultural stimulation, biological diversity, and technological support, it cannot.