Keys to Sustainability

Sustainability has recently become an issue that more and more people are taking seriously. It should have always been a no-brainer but wasn't; but better late than never. Sustainability means, by clear implication, self-sufficiency and self-reliance over the long term.

The current increase in awareness and interest is, of course, partly due to the most serious global economic crisis since the great depression, through which even the uninitiated are finally seeing that our global, perpetual-growth-oriented economic system is no longer sustainable, if it ever was.

Yet, however, when most people think at all about sustainability they are still thinking in terms of economic sustainability, about sustainability of the materialistic lifestyle to which we have become accustomed this past half century, sustainability of sprawling suburbia and the family car, about sustainable development and growth, some way to sustain business as usual. But it's the thought that counts. Right?

The ability to get a significant number of people to think about real sustainability, long-term societal, environmental and species sustainability, is going to require a deep and fundamental change in mindset. The core of sustainability planning can not be that which is itself unsustainable. A problem cannot be its own solution.

I see it all the time, even in the peak oil groups in which I participate. People assume that a certain aspect of civilization or technology which they are particularly dependant upon will survive. So many people assume, for example, that if/when society collapses the internet will survive. It is so useful, after all. But most people are surprised to learn that it takes a tremendous amount of energy and technology to run the internet, especially in its global incarnation with which we have become so accustomed. I have friends in England, Germany, Brazil, South Africa, the U.S., Australia and New Zealand with whom I communicate all the time. It may be by e-mail. It may be live chat, either by text or even, frequently, by video and audio using our webcams. Sure, it's great. But I definitely do not assume that facility will still exist if society and the global economy seriously and terminally collapse.

The basic problem is that people think about changes relative to what currently is. They get fixated on what they are going to lose. They view the whole journey into the future negatively, as a journey away from the present with which they are knowledgeable and comfortable, like somebody moving out of their well-loved old house after the bank forecloses, rather than an exciting journey toward the future, like someone happily choosing to move into a new or different house.

The simple reality that seems to elude most people in the discussion about peak oil is that peak oil means peak food! There are far more people (6.6 billion) on this planet than the planet can sustain naturally, without the use of fossil fuels (many serious and credible researchers estimate the natural carrying capacity to be between 500 million and 1.5 billion). When those fossil fuels go into serious and irreversible decline, which they will, we are going to have to try to feed our massive population without them. Sustainability means, simply, the ability to feed the population, whether that consideration be local or global.

So, forget about the present! Our current society as it is can not survive peak oil. It is the business as usual of our human society that has turned peak oil into a crisis, if not an outright disaster/catastrophe. The loss of oil, after all, is not a crisis by itself. The crisis is created by our deep dependence on oil, especially for the production, processing and distribution of food.

Don't bemoan what we are leaving behind. Think about where we are going forward to. What will that future look like? If you are focused on the past the future will make itself and you will have to live with the results, whatever they are. Only by focusing on that future do you have any potential of controlling what that future will be. One way or another, a post-fossil-fuel future is coming. You can prepare for it but you can't prevent it. The best way not to be negatively affected by oil depletion is to not be dependent on oil. Set yourself free now, and many people are proving that is possible, while it is in your control to do so rather than have it forced on you.

I don't know what the future will be like. There are far too many variables. But I am reasonably convinced that whatever society emerges will not be based on cities as we have come to know them this past century (in recent decades we have reached the point where over half the world's population live in cities). Cities do not, and generally cannot, produce all of the resources they consume nor manage the refuse they generate (Toronto recently went through a 5-week garbage strike during which 25,000 tons of garbage piled up temporary dump sites in parks and rinks).

Modern cities, with their ever-expanding suburban sprawl and centralized concentration of business, industry and labour, are unsustainable, a product of the high energy age that will follow the energy downslope into the abyss. They draw their resources from ever larger externalities, starting with regions criss-crossed with canals and railways at the onset of the Industrial Revolution and now expanded to sucking in resources from all over the globe, those resources moved about the globe by energy-intensive ships and aircraft.

Long term sustainability as we approach and pass the end of the high-energy age is going to have to see a reversal of that trend. The focus will be forced into ever-decreasing spheres, from the global resource base down to the regional and community resource base. Sustainability for a community will mean resource self-sufficiency and community self-reliance. That which a community needs will have to be available within the community or its immediately surrounding area, only rarely by trade with neighbouring communities.

Let's look at some of the key components of that future community self-reliance and self sufficiency.

Seeds

The first key to community self-sufficiency will be food self-sufficiency, the ability of a community to produce all of the food needed to sustain its population. Almost all agriculture today is dependent on centralized seed companies. The crop varieties available are limited, having shrunken steadily since the onset of the Industrial Revolution. Access to seeds is dependent on those central seed companies and an energy-intensive global distribution system. There are several companies, like Monsanto, Archer-Daniels-Midland and Cargill, whose corporate objective is to control the means of global food production. Increasingly seeds are both hybridized and genetically engineered, many with terminator genes so they will not produce seed, negating the age-old practice of seed-saving, saving the seed from this year's crop to produce next year's crop.

As global industry falters and the global distribution system grinds to a halt for lack of energy that seed system will, at first, become increasingly unreliable with the energy expense of distributing anything to rural areas. Eventually it will simply disappear.

For any community to be self-sufficient beyond the end of the oil and high-energy age it is going to have to become both willing and able to produce next year's seed from this year's crop. It is going to have to develop and maintain local crop variations suited to the local climate and soil conditions. This requires critical farming skills that have been lost over this past century that are going to have to be relearned before a community can develop this type of self-sufficiency. This will, of course, require some head start time (reliable estimate is two decades) so that the skills are built up before the industrial seed industry collapses.

There are, however, other aspects of this that require a head start as well. Few farmers today keep on hand seed for two years of crops. Why should they? They get their seed fresh each year from the seed company. If we wait until the seed companies collapse, however, where are the seeds going to come from with which to get started without them? If your crops are already in the ground, assuming they aren't genetically modified with terminator genes, you are going to have to let a significant portion of your crop go to seed at the end of the season in order to have enough seed for next year's crop. But suppose the seed industry collapses in winter or spring, after you have harvested your crops and before new seeds would normally be ordered. You will be absolutely dead in the water.

If you start saving seed now, or soon, you will not only develop skills in seed-saving but you will have your own seed on hand in the event of the collapse of the seed industry. You will also develop the knowledge of what crops are genetically modified and learned to avoid them in favour of natural crops that will produce seed which you can save.

This is not that easy, however. The seed industry is extremely aggressive in protecting its turf. Saving seed from crops produced using seeds purchased from a major seed company will probably be prohibited by law. You need to learn what heritage seeds are available to you, generally from small local seed companies, and use those as your starting point. Even then, however, as was the case with Percy Schmeiser and others, if your crop gets cross-contaminated from a nearby crop from patent-protected or genetically modified seed, you may be prohibited by law from saving seed produced by that entire crop. And the courts thus far have come down very much in favour of the seed companies in these cases. So there are many roadblocks in the way of your early preparation for this and almost all aspects of future sustainability. But persevere.

Water

In order to be self-sufficient and self-reliant on the other side of the energy collapse a community is going to be critically dependent on a safe, reliable, clean water supply. That's a no-brainer, right? There are the municipal water supply, the heavy duty industrial pumps to supply water for crop irrigation, water purification systems, running water in all the houses. All of these, of course, require a heavy investment of funds both to acquire but also to maintain. Once we are seriously into energy decline and the global distribution system begins to collapse and global industry runs into supply and distribution and cost problems all of these systems will begin to break down. Not too long afterward they will simply cease to function. The community is going to need in place a water supply system that is not dependent on fossil fuels, big expensive industrial machinery and equipment, heavy and expensive maintenance, and capable of supplying sustainably all of the community's water needs.

Unless you are starting a new community from the ground up, and I am definitely not recommending this, that is going to have to be done through an established, and probably very conservative, community council. Getting them to replace the current water systems with a new one designed for a post-fossil-fuel age that they do not understand is fast approaching is not going to be an easy task but, as with seeds above, waiting until it becomes a necessity is not going to work. The groundwork is going to have to be laid well in advance.

The safety issue concerns the presence of water management infrastructure upstream from the community. Dams, causeways, canals and canal locks, and other similar infrastructure has a limited lifespan and requires extensive and expensive maintenance. If any of these are upstream from the community the potential for catastrophic inundation of the community is elevated and the potential for interruption of the water supply gets greater over time. Global warming also has a significant potential to impact the future viability of your water supply, both in terms of seasonal flow and contamination. In addition, any industrial infrastructure upstream, such as mining operations with their toxic tailing ponds, has the high potential of contaminating your water source once maintenance of that infrastructure ceases with the collapse of the company or the industry.

Soil Fertility

Soil, like water, is critically important to all life on earth. The foundation for all higher life-forms is the plants that grow in the soil. Over millions of years nature has perfected techniques for creating, building and maintaining soil fertility for crops, fields, woodlands and wetlands.

Unfortunately nature's systems were not built around man. Our use of pesticides kills the important micro-organisms in the soil that are critical to fertility. Our use of artificial fertilizers seriously upsets the natural complex balance of minerals in the soil, those fertilizer focusing on primarily just three elements; nitrogen, potassium and phosphorus. Herbicides destroy the other plants (we call them weeds) that are critical to support for the broad spectrum of soil micro-organisms that create complex soil fertility. Our monocropping encourages the overpopulation of specific groups of micro-organisms at the expense of others. Our plowing of fields upsets and even destroys the soil environment particular micro-organisms need, exposing deep soil organisms to the deadly (for them) air and the sun, suffocating shallow sub-surface micro-organism by burying them deep in the soil. Constant use of heavy farm equipment and plowing have built up a hardpan 6-8 inches below the surface that prevents the movement of critical micro-organisms up and down through the soil, prevents many plants from sinking roots deep enough to get sub-surface water, and builds up a layer of toxins just above the hardpan. Our constant irrigation of crops leaches critical nutrients out of the top soil, causes those crops to develop shallow root systems negating the ability of roots to bring minerals up from the deep sub-soil to the topsoil to nourish plants and micro-organisms and to bring up water from deep within the soil. The combination of over-irrigation and constant application of agro-chemicals has dramatically increased the salt content in the soil, so much so that long-used commercial agricultural soil and even whole farms have had to be abandoned because of the salt burden.

Almost all commercial agricultural soil is sterile, with all the nutrients for plants supplied by fertilizers and other agrochemical additives, soil and plant immune system functions dependent on pesticides and herbicides, water supplied by mechanical irrigation. When the advancing energy crisis forces us to farm without those the fertility needed to grow crops on that soil will simply not exist. It will have to be carefully rebuilt, either by nature or by us, before those soils can produce healthy, abundant crops. With the current levels of global population producing sufficient food on chemically sterilized soils will be impossible, another reality that will force the focus away from global and down to regional and community.

The basic components that must be restored to sterile soils are a full spectrum mineral complex, carbon, organic matter, nitrogen and, most importantly, a broad spectrum of soil micro-organisms. There are many soil improvement techniques that are beneficial, such as creating terra preta soil, but over time the full complexity of living soil must be restored if sustainability is to be achieved.

Farming skills

There is an unfortunate tendency today to think that those who own and run and work on farms are farmers, that they know how to farm. A fairer characterization would be mechano-chemical food producers. Take away their chemicals and their big equipment and and their mechanical irrigation and they wouldn't know where to begin.

There are, in the industrialized world in which we live, very few traditional farmers left and even fewer of their children are choosing to follow in their parents' footsteps. There are far too few to serve as a base for a new, post-fossil-fuel farming industry when the fossil fuels run out and the high-tech farm equipment stops running. That is not to suggest that traditional farming is the only method by which to produce sufficient volumes of food to feed a significant community. Permaculture, for example, is proving to be an excellent technique. But this too requires the long-term development of an extensive, in-the-field skill set, only the rudiments of which can be learned in a classroom.

The farming skills necessary to eke the optimum amount of food out of a piece of land are not easily come by. Even our agricultural schools today tend to focus on chemical/industrial farming techniques. Those fortunate enough to be learning traditional farming skills are doing so at the hand of one of those few traditional farmers still practicing their craft, by apprenticing at their shoulder.

And, of course, today's industrial farms are far too large to be farmed using traditional farming skills. They are designed for and dependent on fossil fuels and large equipment, designed for technological efficiency. They use specialized varieties of seeds to produce crops that can be efficiently harvested with massive mechanization. A return to traditional farming will also necessitate a return to traditional-sized farms, small, labour-intensive farms. The transition from industrial farming to traditional is going to require major land redistribution. The good news is that crop yields using traditional techniques (once the fertility of the soil has been re-established) are 20-50% higher or better.

Sustainable forest management

In any climate, particularly northern climates like Canada and Northern Europe, forests are going to be critical for sustainability in a post-fossil-fuel age. Unfortunately, in the climates in which they will be most needed the forests have long-since been decimated by clear cutting for agricultural land, building materials and urban development and expansion.

Most of the major forests that remain today are not near the population centers that are going to need them in a post-oil world. In a post-oil world forests are going to be needed still for building materials, for fuel, for soil retention and as a habitat for wild animals which will probably increasingly be turned to as a food source. As animal habitat what forests remain are sadly lacking, those forests hacked up into disconnected stands that offer little in the way of contiguous habitat.

In order to not further decimate the forests as fossil fuels run down and then run out a great deal of forest regrowth is going to be needed. It takes, if one includes hardwoods like maple and oak, a hundred years or more to grow a forest from seedlings. Even with the most optimistic peak oil forecasts we do not have that long. There is a lot of reforestation taking place today but most of that is for fast growing softwoods like pine, the objective of which is to quickly produce trees that can again be cut commercially. Sustainable forest management is only being practiced in a few places.

We need a massive, broad-based reforestation effort now to ensure that those forests are going to be there when the fossil fuels can no longer satisfy our needs. We need to stop the clearing and degredation of what forests still remain and give them an opportunity to develop old growth.

Draft Animals

Before fossil fuels farming was conducted using a combination of human and animal power. Before the advent of the automobile the population of horses in North America exceeded the number of humans. Today it is a small fraction of the human population and the vast majority of what stock does exist is for pleasure riding and racing. There are very few draft horses around and even fewer oxen, mules and donkeys.

The amount of labour that is going to be required to produce the food needed for a global human population of 6.6 billion plus when the fossil fuels have gone into irreversible decline is going to be massive. To enter that era without a massively increased stock of draft animals will mean that all of that work is going to have to accomplished with human labour. That will require well over half the human population (experienced) just producing food. It will take a minimum of two decades to build up the stock of draft animals to a level that we can effectively manage food production for that level of population without fossil fuels and mechanized farm equipment.

Non-mechanized farm equipment

Most of the non-mechanized farm equipment still in existence is being used for planters on suburban lawns or as decoration in front of country stores or rusting away behind dilapidated barns. There are few, if any, manufacturers of this equipment left in the industrialized world. An industry to produce such equipment is unlikely to build up before the demand is there for the product.

That presents an interesting Catch-22. The demand is not likely to be there before the fossil fuels needed for mechanized farming have gone into serious decline. It is unlikely that a whole new industry with heavy fossil fuel needs is going to be able to get off the ground when those very fossil fuels have gone into heavy decline. And government subsidies to facilitate development of such an industry are unlikely with a rapidly eroding tax base due to a shrinking labour market with the inevitable demise of industry as we know it.

Additionally that non-mechanized farm equipment manufactured and used in under-developed and developing countries, though it could in theory fill the need in the industrialized world, will not likely become available in the industrialized world due to the lack of raw materials and fuels in the countries of origin and the lack of shipping and fuel for it to be transported to the industrialized world.

Unless the political leadership in the industrialized world accept the imminence of peak oil, understand the implications that that event will encompass, and take it very seriously while there is still time to prepare, the transition to a post-carbon society in the industrialized world is going to be a very painful one.

Of course, another piece of non-mechanized equipment (not necessarily for the farm) that is manufactured and available in abundance in underdeveloped and developing countries is the bicycle. Utilitarian, rugged and, relative to the recreation and sport cycles available in the industrialized world, inexpensive. The bicycle is the perfect personal transport for a post-carbon world.

Trades, Arts and Crafts

Probably the greatest change on the community landscape over the past century is the loss of local community trades, arts and crafts. The former personal and community self-reliance has been traded for the convenience of the global market place driven by the availability of cheap, reliable fuel. Gone is the village blacksmith, the village cobbler, the village tailor, the village dressmaker, the village butcher. Gone are the local handmade furniture, clothings, the owner-built home, the locally-milled grain. Gone are the jacks-of-all-trades, which would describe half the population a century ago. Those trades that still exist within most communities are practiced in specialization to the exclusion of all others.

The village of a century ago could have survived the loss of oil. Hell the people might not even realize it had happened until well after the event when they noticed no trucks had come through town in the past six months. That same community today may have trouble surviving that six months. They would have long since run out of not just fuel but food and probably most durable goods, and be in no position to replace them locally. If that were the dead of winter in most Canadian communities teams of people would have to clean out the bodies in the spring.

Self-reliance.......... Without a global manufacturing and distribution system, or even a national one, self-reliance for the individual and the community, especially rural communities, is critical one we get well into the post-peak era. If the global and national manufacturing and distribution systems to not crash suddenly they will disintegrate gradually, becoming increasingly unreliable until they finally break down. The impact of this will be hardest in rural communities away from the manufacturing centers.

Conclusion

Peak oil is going to mean much more than the loss of oil and derivative fuels and other products. It is going to mean peak food, in an overpopulated world of over 6.6 billion people. The ability to produce food for that level of population with petro-chemical inputs will be severely hampered because of the impact that chemically-based farming has had on the commercial agriculture soils in the industrialized, food exporting countries of the world. It is going to take decades of highly focussed effort to ready ourselves for food self-sufficiency in a post-peak world, decades that should have started long ago.

With billions of lives at stake, including those of people in the industrialized world, we cannot afford to enter the peak oil era naively optimistic that technology will see us through, that we will find and develop alternative energy sources in time. And we certainly can't afford to enter this era blissfully ignorant of the severe ramifications of getting there unprepared.

Origins of Amazonia's Terra Preta Soils

I have been convinced for some time that the Terra Preta soil in any given location is far more than just black carbon supplementation derived from slash and char techniques. I believe, based on my research of online source material on Terra Preta that each patch of Terra Preta soil (there are hundreds, even thousands of such sites known throughout Amazonia and more being discovered each day) has been seeded with Terra Preta soil from another (previous) location. I believe these Terra Preta soils have their origins in the first agricultural efforts on carbon-rich volcanic soils in northwest South America (Ecuador and Bolivia) as land migration into South America from Central and North America by ancient indigenous peoples proceeded.

I am guilty, as are most, of focusing my research on garnering support for my theory and, consciously or subconsciously, rejecting that which does not support it. That having been said, however, I do believe there is a preponderance of research material that is supportive. Following are a number of pertinent quotes from source material that I believe bolsters my position.

Terra preta soils "....contain microbes that are uniquely associated with soils high in BC as compared to adjacent soils....."[1]
There is "....a greater homology between sequences obtained from the four TP sites than between sequences obtained from adjacent and non-TP soils from the same site."[1]
Scientists are having difficulty in developing answers to the Terra Preta mystery. There remain "....many questions still unanswered with respect to their origin, distribution, and properties."[2] Additionally, "....Thus far, despite great effort, scientists have been unable to duplicate production of the soil."[3] The realistic conclusion of the researchers is, "....At the moment, there is a lot of excitement but there’s a lot of work to do.”[3]
Despite many consistencies in Terra Preta soils at different sites, the native characteristics of the altered soil result in many "....varied features of the dark earths throughout the Amazon Basin."[2]
The differences in carbon content in Terra Preta soils suggests that it is not natural in that "....the total carbon stored in these soils can be one order of magnitude higher than in adjacent soils."[2]
The structural similarity of the carbon in Terra Preta soils to charcoal has consistently led researchers to assume that the ".....purposeful application of organic carbon from incomplete combustion may have been the primary reason for the high carbon contents....."[2]
Terra Preta soils have tremendously high fertility. Researchers claim "....terra preta can increase yields 350 percent over adjacent, nutrient-leached soils."[3] Also note, however, that "Amazonian dark earths have high carbon contents that are five to eight times higher than the surrounding soil...."[4]
In a practice that may mimic the original development of widely dispersed Terra Preta soils, "Truckloads of the dark earth are often carted off and sold like potting soil."[3]
A clue to one key aspect of Terra Preta soil is scientific belief that, "....fish residues are an important portion of the high phosphorus concentrations. Phosphorus is really the number one limiting nutrient in the central Amazon."[3] This suggests that the original development of Terra Preta soil may have occurred closer to the sea, on the northwest coast of South America, rather than in Amazonia.
An important key to the uniqueness of Terra Preta soil and, I believe, an important indicator that it may have been seeded from previous sites, is contained in this statement. "You can have the same amount of carbon in terra preta and adjacent soils and the infertile soil won’t change."[3]
Philip Coppens reveals one of the most salient points supporting seeding when he states "....most now argue that people altered the soil with a transforming bacterial change."[4]
One of the most tantalizing clues that the development of Terra Preta soils may have accompanied the gradual populating of the Americas is contained in this statement, "....though science may have long forgotten about this technique, in the highlands of Mexico, these techniques can still be seen at night, when local farmers set parts of their field alight."[4]
Finally the tantalizing question of Terra Preta soil's ability to reproduce itself is revealed in this statement. "In fact, one missing ingredient is how the soil appears to reproduce. Science may not know the answer, but the Amazonian people themselves argue that as long as 20cm of the soil is left undisturbed, the bed will regenerate over a period of about twenty years. A combination of bacteria and fungi are believed to be the transformative agents, but the agents themselves remain elusive from the scientific microscopes."[4]
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1) Isolating Unique Bacteria from Terra Preta Systems: Using Culturing and Molecular Tools for Characterizing Microbial Life in Terra Preta
2) Terra Preta de Indio
3) Terra preta: unearthing an agricultural goldmine
4) Terra Preta - Philip Coppens

Terra Preta Soils - Agricultural Miracle from the Past?

Sometimes we literally can't see the forest for the trees. In recent years there has been a great deal of scientific interest in a soil phenomenon in South America's Amazon River basin, a phenomenon called Terra Preta.

Scientists now understand, though they did not until recently, that Terra Preta soils are anthropogenic, created by man. They were, in fact, created hundreds, even thousands of years ago through the efforts of indigenous peoples living and thriving in the Amazon River basin. It was only recently, through efforts to re investigate myths from Spanish explorers about the fabulous golden cities of El Dorado that the forest behind the trees finally started to come into view.[3] It was through those efforts that the full extent of anthropogenic Terra Preta soils in this area were finally realized. It is estimated that as much as 10%, maybe more, of the soils in the Amazon basin are Terra Preta soils. Only after understanding these magnitudes did archaeologists finally understand how there had been a sufficient agricultural base to support the vast ancient civilizations (now estimated to possibly number into the millions of people) in the Amazon basin, civilizations that, until recently, had largely been written off as myth.

What is Terra Preta soil? Essentially, and it is a mistake to believe this gives a complete understanding of what makes Terra Preta work, Terra Preta is soil that has been enhanced by black carbon, derived from charcoal, and other organic matter. But there is more. A report entitled Isolating Unique Bacteria from Terra Preta Systems: Using Culturing and Molecular Tools for Characterizing Microbial Life in Terra Preta, states, "The greater fertility of Terra Preta (TP) soils is thought to be due to their high black carbon (BC) content, which contributes to increased nutrient and moisture retention, and increased pH. It is likely that the unique chemistry of BC results in distinct microbial communities involved in nutrient cycling and organic matter turnover.[my italics]"[1] With a number of extensive scientific investigations underway on Terra Preta soil, in fact, scientists are coming to realize that the similarities of the bacterial colonies in Terra Preta soils at different locations, even hundreds of miles apart, are far greater than similarities to the bacterial colonies in non Terra Preta soil in areas immediately adjacent to Terra Preta sites.[1, 2]

Here is where I launch into my own speculation. Throughout the history of man nomadic peoples have carried with them from site to site materials and items that are of critical value to them. The Polynesians as they hopped from Pacific island to Pacific island took with them the seeds, roots and seedlings of particular plants that were important to their culture. Early men, as yet not knowing how to create fire, took great pains to carry embers from one fire to start a fire at a new site.

It is not unreasonable to speculate, in fact, that the original pockets of Terra Preta soil were not made by man but rather discovered by man. Over time they may have realized that adding charcoal from their fires to the soil resulted in dramatic increases in fertility. They may have taken this knowledge to a new site and found, in fact, that it didn't net them the results they expected. It may have been, at that stage, that they returned to the site with the fertile Terra Preta soil, gathered up some of that soil and carried it with them to the new site where they mixed it, and more charcoal, into the soil at the new site. It is very unlikely that they would understand what made the original Terra Preta soil so fertile. It would probably have been a form of magic to them, and that Terra Preta soil that they carried from site to site would have been seen as magical in its own rite.

This hypothesis of mine (I'm not claiming it is original or unique but I have not seen similar speculation in other quarters) would clearly explain why the bacterial population in one Terra Preta site is so like that at other Terra Preta sites but unlike the bacterial population in non Terra Preta sites adjacent to Terra Preta sites. The bacteria in the Terra Preta soil did not originate in the soil that was transformed into Terra Preta soil but originated in a Terra Preta site elsewhere and was transported there by the indigenous people who established the new Terra Preta site. This would suggest that the development of the Terra Preta soils throughout the Amazon basin was spread over hundreds, even thousands of years as indigenous peoples criss-crossed the basin moving from one site to another, taking their magical Terra Preta soil with them to seed the soil at the next site.

Regardless of whether my speculation is correct concerning how the different pockets of Terra Preta soil were created, the important point is this. What makes Terra Preta soil work is not the black carbon from charcoal that has been added to the soil. It is the unique population of soil bacteria in that soil that utilizes and thrives on that high concentration of organic carbon. Terra Preta soil, like all soils, derives its fertility not from the mineral content of the soil but from the tens of millions of micro-organisms that live in that soil and make those minerals and other soil nutrients available to the plants growing in that soil.

My caution is this..... do not go out and add a bunch of charcoal or black carbon to your garden thinking it will give you Terra Preta soil with its wondrous fertility. You can, however, buy bags of Terra Preta soil at some better garden centres that can be added to your garden, along with charcoal or black carbon, that will give the desired results.

One more caution..... To my knowledge no scientific testing has yet been done to determine if the bacteria unique to Terra Preta soils can survive in non-tropical soils, most specifically in soils prone to a winter freeze. Until such testing has been completed I would be cautious about trying to duplicate Terra Preta soil in your garden in growing zones subject to winter freeze.


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1. Isolating Unique Bacteria from Terra Preta Systems: Using Culturing and Molecular Tools for Characterizing Microbial Life in Terra Preta - 16-Aug-2006
Authors: O'Neill, Brendan; Grossman, Julie; Tsai, S.M.; Gomes, Jose Elias; Garcia, Carlos Eduardo; Solomon, Dawit; Liang, Biqing; Lehmann, Johannes; Thies, Janice
2. Terra Preta
3. BBC - Horizon - The Secret of El Dorado (see particularly minutes 45-48)