Micro Environment Subsistence System (MESS)

Sustainable Civilization: From the Grass Roots Up
Micro Environment Subsistence System (MESS)Appendix

(Ok, so I tend toward corny names.) The purpose of this appendix is to look at the limits on closing the loop for the safe recycling of human effluents to a growing medium which is a micro-environment optimized for growth of food.

Agriculture is not the results of a happening, an idea, an invention, discovery or instruction by a god of goddess. It is the results of long periods of intimate co-evolution between plants and man.

- Jack Harlan (1917-1998)
American geneticist and plant breeder

To maintain and most effectively implement the advantages of advanced knowledge and technology humans need to live in large dense populations. But in our move to urbanization we have virtually left out plants, the core means of turning sunlight, air, water and soil into fuel and nutrients for our bodies.

Our present population of 6+ billion is dependent on the present global socio-economic-industrial infrastructure not only for economic purposes, but also for "life support" such as food. That infrastructure is itself dependent on cheap, abundant fossil fuels, in particular oil. It is becoming clear that we are approaching the peak of oil production. Prior to the point where oil ceases to be cheap, or abundant, we need alternatives.

Organisms live in many different kind of habitats, which MUST contain a minimum of every life support limiting factor for each species. As the eagle’s habitat is more that a nest, including both land and air, so the habitat for a human is not just a house, it is the rest of the local ecosystem that provides the overall life support for not just the present generation of humans, but for the indefinite future.

The human food chain is the simple progression from plants that absorb sunlight, to the human table. A downward example of a food chain is: The human eats the dog, the dog ate several cats, the catsatelots of mice, the miceatefields of grass which grew by absorbing the sunlight. After the table though, all waste must somehow, eventually, become “food” for something else and be recycled. Small organisms such as insects, bacteria, mold, mushrooms fill a vital niche in an ecology in that they eat dead biological materials and make the atoms and molecules again available as nutrients to grow plants. This takes us to the food web, which is the blend of the overlapping food chains in an ecosystem. A food web is from one celled organisms to bugs, to humans, and everything in-between.

Scientifically acommunity is all of the population that lives together in the same place and interacts. In reality a minimal human food production area is a specialized niche, requiring some particular mix of organisms and physical factors. What are the minimums for such?

If overall loss is minimized, a community of organisms, interacting with each other and the nonliving things in the environment can provide a long term localized ecosystem. A limiting factor is any living or nonliving part of an ecosystem that effects the survival of an organism, such as heat, light, particular atoms or molecules, and water.

Introduction

As far as the physical atoms incorporated into living organizations are concerned, the Earth is essentially a closed system, with the energy of sunlight as the only input and the power source for essentially all life on the surface of the Earth. Much of this document is "generic", based on the theory that once the major nutrient loops are closed further augmentation should not be required. However, my personal focus is "high desert", in Arizona, USA, where water is a significant limiting factor. Every area will have it's on local limiting factor, potentially for most locations the limiting factor may be sunlight and growing season. I've also got to deal with the natural heat, and very low typical humidity.

The optimal human centered ecosystem is physically different from, and essentially incompatible with, any "natural" environment, and must be kept separate. This document combines personal theory, web research into programs such as NASA's CELESS, the Biosphere II project, the work of Ecology Action, and other closed loop food systems, as well as research on optimal food growing methods (hydroponics, aquaponics & aeroponics) and recycling of human effluent, and personal container garden experiments.The area needed to grow food for a fully grown human to survive should, logically, match the area which can be fertilized by human effluents (solid, liquid & gas). Urine, feces, and eventually our physical bodies can all be readily returned to the growing medium.

It is vital to ensure optimal growing conditions for crops, to include exclusion of plant pathogens, aswell as those that may infect humans. The growing area will receive both gray water and black water, which must be handled in a safe manner.

Absent a sealed environment, we lose water vapor, CO2, and other gases. It is obvious that when we grow a crop of which humans eat only a portion, the rest of the plant must be recycled by animals or microorganisms before the nutrients are again available for plant growth. Think of the kernels eaten on an ear of corn, vs the total mass of the plant. This makes crop selection a critical element.

With a typical "first world" diet the upper fertilizing limit for humanure looks to be around 1600 ft. sq. and a potential "minimum" area of 600 ft. sq. as touched on below. Of course, our diets are horrible. If we ate food with greater vitamin content, we would excrete a greater concentration, which would fertilize a larger area. I solicit feedback on vitamin / nutrition standards and what the upper limit is for safe human consumption of various minerals if they are in high concentration in plants.

Every square yard (9 sq. ft.) on the earth's surface with direct, perpendicular un-shaded exposure to the sun receives energy at the rate of around 1kwh (3412 BTU or 859,845 heat calories). The value of a food calorie is 1,000 heat calories, so at 100% conversion each square yard could generate 859 "food" calories per hour. An "average" person needs 2,000 food calories per day. Therefore, if humans were directly solar powered with 100% efficiency, each of us would only need around 22 sq. ft. /hours per day of solar exposure. But of course, we are not directly solar powered, nor are our plants 100% efficient.

If limited to fertilizing 1600 ft. sq., and 6 hour/day of light, the garden must have an overall average efficiency of something just over .225%. But crops for nutrition rather than mere calories do not approach this level of efficiency.

Various health guides indicate humans should "aim" for having our daily calorie intake fulfilled by 40% carbohydrates (1 g = 4 calorie), 30% protein (1 g = 4 calorie), and 30% fats (1 g = 9 calorie).

PLASTIC CONTAINERS

To use recycled plastic in a garden, check the recycling label, an arrowtriangle on the bottom of the container encircles a number 1-7.

1. Clear plastic bottles (soda, water, etc.), formally known as PET. Thismaterial is considered safe for planters. However, it does have a tendencyto colonize bacteria on its surface. So wash it between uses if you aredrinking from it.

2. Opaque plastic jugs (milk jugs, butter tubs, etc.). HDPE. Thismaterial is considered safe.

3. PVC. Plumbing pipes and food wraps. When this material gets hot, itleaches chemicals that mess with your hormones.

4. Grocery bags and squeeze bottles. LDPE. This material is consideredsafe.

5. Wide necked milky white containers (yogurt). Formal name isPolypropylene. This is currently considered safe.

6. Styrofoam. This material leaches toxic chemicals when heated. So, youmight also want to avoid heating food in a microwave with it.

7. Everything else. Just avoid it. This is a chemical soup of uncertainorigin and process.

In summary, build your garden projects with plastics that have the numbers1, 2, 4, and 5 (milk jugs, plastic bags, and yogurt cups). Avoid the rest.

Overview of Plant needs

The basic needs of plants are nutrients (certain atoms in certain forms), water, and light. On the scale of the Earth, our entire ecosystem is an essentially sealed environment.

Air

Plants need three primary gases from air.

Carbon Dioxide (CO2), which is used in their leaves in the photosynthesis process to combine hydrogen from water with carbon from CO2 to produce carbohydrates (sugars), with the oxygen being released. In normal seal level air, CO2 is at 350 parts per million (ppm), or .035%. Even this tiny amount is enough to support plant growth. Studies seem to show that the upper concentration limit for CO2 for plants is around 4%, which requires that all other growing conditions be optimized. But, plants cannot tolerate the 4% level unless there is sunlight present for photosynthesis. WARNING: In general, humans cannot breathe where the CO2 concentration approaches 3%.

Water will absorb it's own volume of CO2, and when evaporated will release the CO2. This seems nicely in tune with nighttime water condensation absorbing CO2, with daytime evaporation releasing the gas.

Oxygen for their roots. Roots can suffocate or drown without enough O2. Conversely, as aeroponics shows given access to nutrients and kept moist, roots and the plant will thrive when given lots of air. Aeroponics is cited as perhaps the most productive means of providing crops necessary nutrients. Aeroponics has plants suspended in holding material, in an air gap, which is kept in a spray of the liquid nutrient. The falling liquid also gains air which provides O2 for the roots in the liquid below. I continue experiments on a static means to approximate this. I’ve had modest success with containers set up with a bottom wick kept moist by an upturned bottle of water, several inches of perlite over the wick, then a tower of perlite up the center with compost around the tower. A WARNING: You may have heard that more houseplants are killed by overwatering than by underwatering." The problem with overwatering is not that the roots do not like to stay moist, but that if heavily watered, water fills most of the spaces ordinarily filled by air in dry soil. Plant roots require oxygen, but not all portions of a plant's roots require the same amount of oxygen. Plants can form what he calls oxygen (O) roots and water/nutrient (W/N) roots. Roots exposed to air specialize in taking up oxygen; those immersed in water specialize in taking up water and nutrients. When the water level drops in a plants growing medium, the W/N roots change into O roots, a process taking only 2-4 days. However, this is not reversible. If water returns to the original depth the plants wilt within a few hours and do not recover. You need to create a medium with such large air spaces that no matter how much water is around, the roots will still find plenty of air, but dense enough that water can move up by capillary action and keep the medium moist.

Nitrogen (79% of the air) to produce complex molecules. Most plants cannot absorb nitrogen directly from the air on their own, but must obtain it via their roots from a substance which embodies the gas atom.

The bulk of commercial nitrogen fertilizer is made using un-sustainable high energy chemical processes.

There are various methods to "fix" the gas into the soil, for example special bacteria, that can live in symbiosis with some plants:

Clover, alfalfa, select legumes, and select trees such as Neem and Russian Olive. Research what grows well in your area. It is the bacteria that make nitrogen available for absorption by plant roots. Fixing nitrogen takes energy. Every gram of nitrogen fixed requires 10 gram of glucose, with the plant feeding the bacteria growing on it's roots.

Blue-green algae can also absorb nitrogen and incorporate it into their cells, with the advantage it can be used as an animal (or human) food, or as fertilizer.

Lightning splits the N2 molecule, which can then combine with oxygen into a nitrogen oxide which can dissolve in rainwater, which was something that Tesla referenced in several of his papers.

In a free online pamphlet, Bill Mollison presents his "third world endless nitrogen fertilizer supply system." Youwill need a sand box, with a trickle-insystem of water, and a couple of subsurfacebarriers to make the waterdodge about. Fill the box with whitesand and about a quarter ounce of titaniumoxide (a common paint pigment). He indicates that in the presence of sunlight, titaniumoxide catalyzes atmosphericnitrogen into ammonia, endlessly. Youdon't use up any sand or titanium oxidein this catalyic reaction. Ammonia is highly watersoluble. You run this ammonia solutionoff and cork the system up again. Youdon't run it continuously, because youdon't want an algae buildup in thesand. You just flush out the systemwith water. Water your garden withit. Endless nitrogen fertilizer. If youhave a situation where you want toplant in sand dunes, use a pound ortwo of titanium oxide. You will quicklyestablish plants in the sand, becausenitrogen is continually produced aftera rain. This solution is carried downinto the sand. If you are going to laydown a clover patch on a sand dune,this is how you do it.

Apart from the legumes and actinorhizal plants, there are a number of other systems involving nitrogen-fixing cyanobacteria, notably of the bacterial genera Azotobacter, Anabaena, and Nostoc. These systems involve the following:

1.Gunnera-Nostoc. Probably all Gunnera species display alocalised infection of the stem by Nostoc bacteria.

2.Azolla-Anabaena. The aquatic plants of the Azolla family form asymbiosis with Anabaena bacteria.

3.Liverwort-Nostoc. The liverwort genera Anthoceros, Blasia andCavirularia all form associations with Nostoc bacteria.

4.Lichen associations. About 7% of lichen species are not of thetraditional fungi-algae symbiosis, but are instead formed of a fungi-cyanobacteria symbiosis. Nostoc in the bacteria genus is usually involved. The lichen genera Collema, Lobaria, Peltigera, Leptogium and Stereocaulon form this type of symbiosis. They are particularly important as nitrogen-sources in Arctic and desert ecosystems, where fixation rates may reach 10-20 Kg/ha/year.

5.Leaf surfaces (the phyllosphere). There is increasing evidencethat free-living N-fixing species of bacteria are abundant on wet and damp leaves in predominantly moist climates.

6.Root zone (Rhizosphere). Free-living bacteria, for exampleAzotobacter species, may be more abundant in the areas immediately adjacent to plant roots and aid plant nitrogen nutrition.

7. Free-living. N-fixing bacteria thrive where the Carbon:Nitrogen ratio is high and there is sufficient moisture, for example on rotting wood, in leaf litter, the lower parts of straw and chipping mulches etc.

FACTORS AFFECTING NODULE DEVELOPMENT

1. Temperature. Depends on the bacteria species and the host plants, for example 4-6 deg C is adequate in Vicia faba, whereas 18 deg C or more is necessary for most sub-tropical and tropical species.

2. Seasonality. For most species, fixation rates rise rapidly in Spring from zero, to a maximum by late spring/early summer which is sustained until late summer, then decline back down to zero by late autumn. In evergreen species, N-fixation occurs throughout the winter provided the soil temperatures do not fall too low.

3. Soil pH. The legumes are generally less tolerant of soil acidity than actinorhizal plants. which is reflected by Rhizobium species being less acid-tolerant than Frankia species. Of the actinorhizal plants, Alders (Alnus spp) and Bayberries (Myrica spp) are most acid tolerant. Of Rhizobium species, acid-tolerance declines in the following order: cowpea group (most acid tolerant) - Soya bean group- Bean & Pea groups - Clover group - Alfalfa group (least acid tolerant).

In poor soils which are low in Nitrogen, the introduction of N-fixing plants usually leads to considerable acidification (e.g., a fall in pH of up to 2.0 in 20 years for a solid stand), which itself will in time start to affect nodulation efficiency.

4. Availability of Nitrogen in the soil. If Nitrogen is abundant and freely available, N-fixation is usually much reduced, sometimes to only 10% of the total which the N-fixing plants use. In trials with Alders, at low soil N levels (under 0.1% total soil nitrogen), the majority of N used by the alder comes from N fixed from the air; when total soil nitrogen is as high as 0.5%, only 20% of the N used came from fixed N from the air.

5. Moisture stress. In droughts, bacterial numbers decline; they generally recover quickly, though, when moisture becomes available again. Some species (usually actinorhizal), for example Alnus glutinosa and Myrica gale, are adapted to perform well in waterlogged conditions.

6. Light availability. Nitrogen fixation is powered via sunlight and thus will be reduced in shady conditions. For most N-fixing plants, which are shade sensitive, N-fixation rates decline in direct proportion to shading, i.e. 50% shading leads to 50% of the N-fixed. The relationship for N-fixing species which are not so shade-sensitive is not so clear: they may well continue to fix significant amounts of nitrogen in shade.