Post Peak Dam Maintenance, or Lack Thereof

"Dam failures are of particular concern because the failure of a large dam has the potential to cause more death and destruction than the failure of any other man-made structure. This is because of the destructive power of the flood wave that would be released by the sudden collapse of a large dam."[2] What will be the fate of the world's large dams after peak oil as energy declines, technology falters and budgets for inspection and maintenance of these critical and dangerous facilities begin to be pared back in deference to perceived more immediate societal priorities?

(See also; The myth of permanence: post-peak infrastructure maintenance, The Emerging Global Freshwater Crisis, and Lake Ontario & St. Lawrence River after Peak Oil in my blog.)



Most major cities, both globally and here in Canada, were born, developed and have evolved on the low-lying land adjacent to major bodies of water, either saltwater oceans, seas, bays and inlets or freshwater lakes and rivers. The cities sitting on saltwater shores seem to have been built with the dangerously misguided assumption that sea level is and will continue to be constant. The cities on freshwater shores are largely protected by a cornucopia of technology and infrastructure that has essentially stabilized water levels in the bodies of water on which they are situated.

In recent years, with the growth of scientific research and knowledge of global warming, there has been considerable attention paid to the risk faced by major cities over this next century from the potential sea-level rise that could result from the meltdown of glaciers and, most importantly, polar ice caps (79% of the world's fresh water is locked up in ice and snow). Very little attention has been paid, however, to the risk faced by major cities situated on freshwater shores that could result from the potential post peak-oil disintegration and collapse of the technology and infrastructure containing and controlling billions of tons of water upstream from these major cities. There are numerous internet sites that show the inundation risk of coastal areas from sea level rise. Very little has been done on inundation mapping downstream from major dams. That is not to suggest that smaller communities are not subject to the same risks, as most communities have evolved in the same way, on low-lying land adjacent to lakes, rivers and seas.

There are about 80,000 dams in the U.S., for example, the majority even today over fifty years old. According to FEMA, "Approximately one third of these pose a "high" or "significant" hazard to life and property if failure occurs."[1] It is important to note, here, that "high" and "significant" are from a national perspective in terms of potential dollar damage and potential deaths. As the report Flood Disasters in Canada[6] suggests, risk analysis statistics are "biased towards the more densely populated areas ..... where floods are more likely to impact humans." A dam failure upstream of any populated area would, however, be considered "significant" for those living downstream. According to the National Performance of Dams Program (NPDP), "at least 85% of the more than 75,000 dams in the the US will be in excess of 50 years old by 2020." The report goes on to stress, "Perhaps more significantly, most of the large dams throughout the US are also approaching old age."[5] There is, of course, a reason for this impending flush of aging dams. According to the report Dam Construction[7], "Within the U.S., the most active period of dam building occurred between 1950 and 1970, and has been called “the golden age of dam building” (Doyle et al., 2003). The same comment is frequently made about the situation in Canada." In Ontario today, "In the case of Ontario Power Generation’s almost 200 dams, nearly two thirds are in excess of 50 years old."[5]

Generally there is now a trend in Canada to move away from the large hydro megaprojects. "Because of the size, cost and negative environmental impacts of large dam projects, hydro development has been increasingly focused on small-scale projects, i.e., those with less than 10 MW of generating capacity. Many of these are run-of-the-river projects. There are currently more than 300 plants in Canada with a capacity of 15 MW or less (Industry Canada, 2003) and numerous others under consideration, particularly for remote communities that rely on high-cost diesel generation. Approximately 5500 sites in Canada are technically feasible for small-scale hydroelectric production (Natural Resources Canada, 2000)."[7] Though this means a reducing risk of failure of large dams, it increases the number of dams being built in proximity to and designed to service population centers, many remote where emergency response to a disaster would be delayed because of that remoteness.

Fifty years used to be considered the average life expectancy for dams. Not to suggest that the statistics or studies are being slanted but, with the rapidly ageing inventory of North American dams, a report entitled Dam Construction suggests, "Based on extensive U.S. experience, the life span of typically unmaintained dams is conservatively estimated at 75 years, refuting the common misconception that the average life of a dam is 50 years (Donnelly et al., 2002)."[7] Gee, ain't that lucky. I guess that takes the pressure off. The public relations importance of this statement is twofold, first the supposed refutation of the 50 year lifespan but, also, the inclusion of the phrase "typically unmaintained dams". Numerous studies by the International Joint Commission (IJC), FEMA, the National Performance of Dams Program (NPDP), and others, have suggested that even where dam safety programs exist and inspections occur, the vast majority of North American dams are not being maintained effectively today, many not even regularly inspected. The IJC, for example, considers the three dams involved in the international Moses/Saunders hydro dam facility at Cornwall Ontario and Messina New York (these dams hold back the waters of Lake Ontario from the St. Lawrence: the Great Lakes containing 22,573km3 of water, 22.573billion m3, enough water to cover 18.3 million acres of downstream land to a depth of 1 foot), to be potentially unsafe due to lack of inspections and maintenance. Even if the average life expectancy of a dam is 75 years rather than fifty as the above report suggests, that still means that the huge glut of dams built between 1950 and 1970 will all pass that average life expectancy by the middle of this century, at a time when the energy, technology and economy for their increasingly necessary maintenance or their decommissioning will be in serious decline. With the average life expectancy of a dam, whether that be fifty years or seventy-five, the cost and complexity of decommissioning is most often as high as it was for the original construction. There is a significant risk beyond peak oil that dams may simply be de-operated (stopping the usage and maintenance) rather than decommissioned (properly torn down and replaced or returning the river to its natural flow). The track record of site decommissioning, whether dams, nuclear sites, toxic chemical sites, or others, has not been good. There is no reason to expect that it will improve under the difficult circumstances we will face on the other side of peak oil.

Whether or not the focus on "typically unmaintained dams" in the above report is based on a knowledge of peak oil and its implications, it does suggest an awareness of widespread concerns about the future maintenance and maintainability of dams and related infrastructure. A report entitled Risky Business for Dams[5] makes the following statement, "Dam owners are facing increasingly difficult decisions about the ways in which finite financial and human resources should be allocated to ensure the continuing safe operation of ageing dams. Without such investment, dam failure is not only a possibility but can be an expected consequence of lack of proper maintenance and diligence by a dam owner." Washington State alone lists more than a dozen dam failures in the last two decades, despite the level of current technologies, full energy availability and a vibrant economy.[4]

Canada is a large, cold nation. We have significant energy needs for transportation, for infrastructure and industry, and for home heating, cooling and cooking. As the global and national reserves of fossil fuels (oil, natural gas and coal) diminish over the course of this century Canada's needs for energy will still remain high. More and more people will, as fossil fuels decline, revert, out of necessity, to the use of wood for heating their homes and cooking their food. Canada is still blessed with an abundance of temperate forests. These forests, however, are generally not in the same locations as the population concentration. The amount of forest cover in populated areas has already diminished to minuscule levels. The pressures put on that remaining accessible forest cover in the search of fuel for home heating and cooking will become increasingly severe over the balance of this century.

This large-scale reversion to the use of wood for heating and cooking will have a major and increasing impact on the viability of the nation's dams. As forest cover is removed from the hills and fields of a river's watershed (especially in the case of clear-cutting), and with the increasing pressure on those lands for food and feed crop production, the amount of soil and plant material carried by that river will increase, particularly after major weather events. There have been countless examples - globally moreso than locally - of the devastating impact of flooding when a watercourse in flash flood fills with silt and debris from upstream. Often whole communities are buried in mud or wiped out by being carried away by torrents of water. With the anticipated increase in the removal of forest cover for fuel, with the loss of it's impact on the ability of the soil to absorb and retain moisture, and with the anticipated increase in severe weather events due to global warming, the volume of silt and debris in future flood events expose Canadian rivers to the type of catastrophic flooding we have seen elsewhere in the world. The risk of dam overtopping on managed watercourses (which includes most rivers flowing through populated areas) increases dramatically under such circumstances as the volume of flood flow includes as much or more silt and debris as water. That increase in silt carried down from upstream will also dramatically increase the silting up of the reservoir behind the dam. This means the reservoir will have less water for power generation or downstream usage. It also increases the risk of overtopping during extreme weather events as dams will more commonly be run at their maximum reservoir level leaving less margin in the silt-shallowed reservoir for absorbing the sudden run-off.

There is little reason to believe that once we have passed peak oil and the global economy implodes that future maintenance and commitment to safe decommissioning will increase as the tens of thousands of North American dams age. Historically, societies have simply abandoned infrastructure as the society disintegrates. A society in decline simply no longer has the resources to live up to those well-intentioned commitments made when that society was at its peak. The dam-building golden age of the 1950s to 1970s was an age without the foresight of peak oil and its implications for technology and the global economy. That glut of dam building happened without an awareness of the probability that all of those dams would reach old age at a time when society will have gone into terminal decline. It's like a commitment made to maintain a nuclear waste dump in perpetuity as long as the radiation levels in the stored material remain dangerous. It is easy to make such commitments when you see things continuing as they are indefinitely into the future. "All things being equal....." will simply not apply on the other side of peak oil. The rules will have changed. The people who made those commitments in the past will no longer be around to shoulder the responsibility to deliver on those commitments. That will fall to people struggling with simply trying to figure out how to survive the collapse.



--------------------------------------

The following were key documents in the research for this article;
1) FEMA: Dam Failure
2) Dam Failures
3) Notable Dam Failures: Recent Dam Failures and Lessons Learned
4) Reasons for Dam Failures
5) Risky business for dams
6) Flood Disasters in Canada
7) Dam Construction
8) Hydroelectric power generation

Lake Ontario & St. Lawrence River after Peak Oil

The water levels in both Lake Ontario and the St. Lawrence River are maintained by a significant amount of man-made technology and infrastructure. Principally this is achieved through a series of three dams; the international Moses-Saunders Hydro-Electric Dam at Cornwall Ontario and Messina New York, the Long Sault Dam at Long Sault, Ontario which acts as a spillway when outflows are larger than the capacity of the power dam, and the Iroquois Ice Dam at Iroquois, Ontario which is principally used to help form a stable ice cover and regulate water levels at the power dam. There are also a number of additional dykes, levies and flood control channels and canals such as the 17km Beauharnois Canal which bypasses the Soulanges rapids and carries 84% of the water flow of the river to the Beauharnois power station.

The International Joint Committee (IJC) established by the governments of the United States and Canada is charged with oversight responsibility for boundary waters shared by the two nations, most importantly including the Great Lakes/St Lawrence basin. Part of their mandate is to, through controlling the flow through these various facilities, "regulate Lake Ontario within a target range from 74.2 to 75.4 metres (243.3 to 247.3 feet) above sea level." This involves, unfortunately, a number of variables over which the IJC has no control;

* Global warming is already causing a slight rise in global sea levels and is expected to cause significant rises in sea levels over the coming century, particularly with the anticipated partial or complete melt of the Greenland ice cap and the Antarctic ice cap. Does the IJC then continue to maintain Lake Ontario water levels relative to rising sea levels or does it "fix" the sea level relative to which Lake Ontario levels are maintained?
* Global warming could, additionally, have serious impact over rainfall and snow levels over the Great Lakes basin and the full area that drains into the basin. In this past decade alone precipitation levels in the region have changed significantly. Although the IJC charter allows for significant changes in future weather patterns and inflows, the specifics of how the IJC will respond have not been spelled out.
* The Great Lakes basin drains nearly half a continent. The IJC has no jurisdiction over rivers and tributaries feeding the Great Lakes basin which are wholy contained within either the U.S.A. or Canada, a significant shortcoming of the existing IJC mandate. These waterways, and any infrastructure on them that could affect Great Lakes inflow, fall under the jurisdiction of a hodge-podge of state, provincial, federal, county and municipal governments and their agencies.
* Controlling the levels of Lake Ontario does not automatically control the flow through the St. Lawrence. That is dependent on inflows to the Great Lakes. But St. Lawrence river levels are also affected by other major inflows downstream from the control infrastructure, such as the Ottawa River and Richelieu River.

Worrisome from a post Peak oil perspective is the long-term viability and maintenance of this infrastructure. This concern has been expressed by the IJC itself. In a recent IJC report entitled Unsafe Dams? the IJC stated "In recent years, the Commission has reviewed the terms of some of its Orders of Approval for the construction of such structures. It has become aware that some of its Regulated Facilities are in need of repair and that some existing programs have not ensured that these repairs were made. ..... Existing legislation, regulations, practices and government oversight are insufficient to ensure that Regulated Facilities are safe." Specifically included in this concern are the three dams through which Lake Ontario and St. Lawrence River water levels are managed.
These facilities have now been in existence for several decades. This presents an obvious concern which the IJC have echoed, "Some Regulated Facilities were built early in the century. With aging facilities, maintenance programs are an absolute necesssity. Continuing maintenance programs are being implemented in some cases. Monies that owners budget for maintenance work are, however, sometimes not spent." In the case of the U.S. portion of the Moses/Saunders hydroelectric facility, much of the electricity generated is sold off to two key industries; the Aluminum Company of America (ALCOA) and General Motors Corporation (GM Powertrain). Most of the rest is sold off at cost to electric supply utilities across New York State. Should either or both of ALCOA or GM fail (GM's survival is even now in question), considering that maintenance and inspection are even now questionable, where will be the economic motivation to maintain the facility?

It is important to note that, at this time, the Canadian Federal government and the Ontario Provincial government have no established Dam Safety Program, though the Ontario Government is said to be working on one. Many of the major river systems feeding into Lake Ontario and the rest of the Great Lakes are controlled by a series of dams. The Trent River system feeding into Lake Ontario at Belleville/Trenton is a good example. In the lower reaches of the Trent River alone, from Frankford down to the Bay of Quinte, there are more than half a dozen major dams. Each of these dams holds back from 10-30 feet of water or more. Should any one of these dams fail, especially a dam further upstream, the volume of water released would simply inundate any dams further downstream, possibly leading to a domino collapse of dam after dam. The impact on Belleville, Trenton and all of the low-lying areas of Prince Edward County would be devestated.

Whether the Ontario Government is working on establishing a Dam Safety Program is, of course, a moot point in the face of a pending peak in global oil production and the potential severe impact on the global, American and Canadian economies. All dams, especially as they age, require significant ongoing maintenance and regular inspection. This is particularly so in a cold climate such as that in the Great Lakes basin with its severe seasonal variations and stresses on infrastructure, particularly dams. Whether the funds for inspecting and maintaining such infrastructure will be available in a collapsing economy is a reasonable question. Whether what funds are available will be spent on the appropriate inspection and maintenance is just as fair. Maintenance is always one of the first things to suffer when budgets get tight. There's no profit in maintenance.

In my article The myth of permanence: post-peak infrastructure maintenance, I explored the potential of future infrastructure maintenance problems on a broad range of sociatal infrastructure. Nowhere, in my opinion, is this more critical than with regard to dams. The Great Lakes contain a full 18% of the total surface freshwater on the planet. All of that water is kept in check by hundreds of dams controlling both outflow and inflow. That is a tremendous amount of aging infrastructure that will need increasing amounts of energy-intensive maintenance to remain viable. The energy that was available during the era when all that infrastructure was built won't be available when it all has to be replaced or decommissioned. The results could be catastrophic.

The Emerging Global Freshwater Crisis

Seventy percent of the earth's surface is covered with water yet more than one out of six people (1.1 billion) lack access to safe drinking water, and more than two out of six (2.6 billion) lack adequate sanitation.[16] And those numbers grow every year. Now over half the world's population live in heavily energy-dependent cities whose aging water infrastructure, even now before peak oil, is beginning to crumble. Even in wealthy North America, the cost of renewing and modernizing water and wastewater infrastructure is enormous, and there is urgency for rational assessment and informed decision making about the need for new or expanded infrastructure and about potential impacts on Great Lakes waters.[12] Where will peak oil leave us?



Earth. The water planet. Or, as Carl Sagan called it, the pale blue dot. Water, water everywhere. The oceans and lakes are full of it. The poles are covered with it. Rivers move it from place to place. Blocks of it measuring thousands of cubic kilometres float about the oceans near the poles. The atmosphere is full of it. All the plants and animals on the planet are made up mostly of it. It's in the soil, even in the rocks. It exists as a liquid, a solid, a gas. On a planetary basis it is a perpetually-recycled finite resource. It has been estimated that, in total, the earth contains about 1400 million cubic kilometers of it, give or take a few million.[15] But it's not always conveniently in the place and in the form we humans want it to be.

It's plentiful, but can you drink it?

Of all of the water on the planet only a paltry 2.5% or about 35 million cubic kilometers is fresh water. The usable portion of those freshwater resources is less than 1% (about 350,000 cubic kilometers) and only 0.0025% of all the water on earth. The total global freshwater breaks down as; 0.3% contained in lakes and rivers (90% of it in lakes); 29.9% fresh ground water (aquifers); 0.9% other: swamp, soil moisture, tundra and permafrost; 68.9% ice caps, glaciers and snow cover.[15] And the atmosphere itself contains about 0.001% (0.4% of global fresh water) of the total water available on our planet.[17]

But fresh water is not evenly distributed throughout the planet. The Great Lakes contain about 18 percent of the world’s surface freshwater supplies - shared by only two nations - with a combined surface area of over 325,000 km2. Overall, however, jurisdiction for the Great Lakes is shared by two federal governments (Canada and the United States), two Canadian provinces (Ontario and Quebec), eight US states (New York, Pennsylvania, Michigan, Ohio, Illinois, Indiana, Wisconsin, and Minnesota), and hundreds of municipal governments.[12] Only about 25 million people (about one third of 1% of the global population) rely on the Great Lakes for their drinking water.[12]

At the other extreme, the 29 countries in the near east region account for 14% of the world’s land area and are home to 10% of the world’s human population. Yet the whole region has only about 2% of the world’s renewable freshwater resources.[15] While the global average availability is 7000 cubic meters of water per person per year, in these countries the average is 1577 cubic meters of water per person per year.[15] In Jordan and the six Gulf Cooperation Council countries of Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates only 170-200 cubic meters of renewable water resources are available per person per year, less than 3% of the global average.[15]

From this limited availability of fresh water, however, withdrawals for irrigation represent an average of 66% of the total withdrawals (up to 90% in arid regions like the middle east), the other 34% being used by domestic households (10%) (representing only 17-20 cubic meters per person per year in the above-mentioned countries), industry (20%), or evaporated from reservoirs (4%).[16]

Population growth, economic development, and changing national and regional values have intensified competition over increasingly scarce freshwater resources worldwide, leading to widespread concern and predictions of increasing future conflicts over shared water supplies.[8, 10, 11, 13, 14, 16] Of greatest concern is the potential for conflict within the world's 263 international freshwater basins (basins shared by two or more countries). However, since 1948, the historical record documents only 37 incidents of acute conflicts (i.e., those involving violence) over water, over half between Israel and various of its neighbours. During that same period, approximately 295 international water agreements were negotiated and signed.[10] It is unlikely that that ratio will hold over this century as water shortages become increasingly common and critical.





Europe has the largest number of international freshwater basins with 69, followed by Africa with 59, Asia with 57, North America with 40, and South America with 38. The world's 263 international freshwater basins account for nearly one-half of the earth's land surface, generate roughly 60% of global freshwater flow and are home to approximately 40% of the world's population. A total of 145 countries contribute territory to international basins, some albeit reluctantly. Thirty-three nations, including such sizable countries as Bolivia, Chad, the Democratic Republic of the Congo, Niger, and Zambia, have more than 95% of their territory within the hydrologic boundaries of one or more international basins. Needless to say such countries take their international water agreements very seriously.[10]

Many international freshwater basins involve a significant number of nation states. The Danube, for example, has seventeen riparian states. The Congo, Niger, Nile, Rhine, and Zambezi are each shared by more than nine countries. The Amazon, Aral Sea, Ganges-Brahmaputra-Meghna, Jordan, Kura-Araks, La Plata, Lake Chad, Mekong, Neman, Tarim, Tigris-Euphrates-Shatt al Arab, Vistula, and Volga basins each contain territory of at least five sovereign nations. In all, and most worrisome from the perspective of potential future conflicts, 158 of the world's 263 international freshwater basins lack any type of multilateral cooperative management and conflict resolution framework. Of the 106 basins with water institutions, approximately two-thirds have three or more riparian states, yet less than 20 percent of the accompanying agreements are multilateral, most being bilateral between only two of those states. Many basins continue to experience significant disputes even after a treaty is negotiated and signed, often because of the exclusion from the treaties of one or more of the sharing states. Often, under such pressures, even the signed bilateral treaties begin to break down.[10]

An early and successful model of cooperative water management structures that can help avoid dispute and conflict was the establishment by the United States and Canada of the International Joint Committee (IJC) for the administration of the Great Lakes watershed and connecting and outflowing rivers.[12] Though somewhat unique because of its focus on shared lakes more than the shared rivers, it is, nonetheless, a model of the level of cooperation that is achievable. Certainly the relative lack of complexity in being only a bilateral agreement has helped considerably as well. It is fair to say, however, that a significant part of the strong and enduring relationship between the two countries is due, at least in part, to their mutual cooperation concerning and national reliance on the Great Lakes. Even so, at least one war (the war of 1812) has been fought between the two nations (Canada was a British colony at the time) partly on the waters of these very shared lakes.

Water has always been an important component in the negotiations between states and nations. The Food and Agricultural Organization (FAO) of the United Nations has documented more than 3600 international water treaties - covering the surface water in lakes and rivers - dating from AD 805 to 1984.[10] Most of these have to do with rights of navigation, limits on diversion and pollution. The earliest recorded water treaty, however, dates back to 2500 BC, when the two Sumerian city-states of Lagash and Umma crafted an agreement ending a water dispute along the Tigris River.[10] Since 1948 alone 295 international water agreements were negotiated and signed dealing with surface freshwater.[10] Yet the surface water at issue represents only 0.3% of the total freshwater on the planet. As regards groundwater or the underground water in aquifers, which accounts for 29.9% of all the freshwater on the planet, "there are no known treaties dealing specifically with groundwater matters."[13] Some freshwater treaties dealing with surface water do casually mention groundwater - almost as an aside or a point for future consideration - but even these treaties do not pursue the issue with any detailed language, measures, agreements or definition.

Groundwater, of course, is considerably more difficult to map and define than is surface water. There are literally thousands of underground aquifers throughout the world, most fortunately contained within the boundaries of single sovereign nations. But hundreds of these aquifers run beneath and across the arbitrary human boundaries above them. And just as one state excessively drawing water from a shared lake or river affects the availability of that resource to other countries sharing it, the excessive drawing down of the water in an international aquifer by one state affects the availability of that water to the other states dependent on it. For example, South Africa shares four rivers with its six neighbours – the Incomati, Orange, Limpopo and Maputo. The water in these rivers is, however, increasingly under pressure due to increased water demands in relatively affluent South Africa, the largest, most powerful of the seven nations sharing those resources.[11] This is not a trivial issue when it comes to groundwater resources. Groundwater systems are often the only source of fresh water in some regions of the world, particularly under arid and semi-arid climatic conditions - such as in the middle east and much of Africa - where demand is rapidly increasing.[13]

The structure and terminology of most international freshwater agreements tend to follow the pattern codified in the 1997 United Nations Convention on the Law of the Non-Navigational Uses of International Watercourses.[10] Attempts have been underway, through the International Shared Aquifer Resource Management (ISARM) efforts[13], to arrive at a similar codification of rules for treaties involving the treatment of international groundwater aquifers. The most recent attempt, The Seoul Rules, demonstrates special concern with international groundwater through the provision of specific articles that relate to “hydraulic interdependence”, “protection of groundwater” and “groundwater management & surface waters” (the latter addresses the issue of conjunctive use).[14] It is still too early to tell what success these efforts will have or whether anything equivalent to UN convention will result. The slow progress to date suggests that there is only a slight likelihood of having a framework in place in time to ward off serious future water conflicts. Issues of increasing water scarcity, degrading water quality, rapid population growth, unilateral water development, and uneven levels of economic development are commonly cited as potentially disruptive factors in co-riparian water relations. The combination of these factors has led academics and policy-makers alike to warn of impending conflict over shared water resources.[10]

Even when nations equitably share these resources, however, the pressure on groundwater resources, both shared and sovereign, can be immense. Groundwater reserves in the Middle East, for example, are becoming increasingly brackish. More than 50% of groundwater in the region, it is estimated, is already saline and the proportion is increasing as the rate of extraction of water from aquifers exceeds recharge, in much of the region by three to one. In Saudi Arabia water levels declined by more than 70 meters in the Umm Er Radhuma aquifer from 1978 to 1984 and this decline was accompanied by a salinity increase of more than 1000 milligrams per liter. The aquifers of Bahrain, the Batenah Plains of Oman, and the United Arab Emirates are suffering severely from seawater intrusion. Groundwater salinity in most areas of the Syrian and Jordanian steppe has increased to several thousand milligrams per liter and over exploitation of coastal aquifers in Lebanon has caused seawater intrusion with a subsequent rise from 340 to 22000 milligrams per liter in some wells near Beirut. With the countries in the Arabian peninsula using up their water resources three times as fast as they are being renewed it is estimated that available water resources will be exhausted within 20 years unless consumption of freshwater is reduced.[15]

The always volatile countries of the Middle East have become critically dependent on the income from their oil resources and accompanying natural gas, essentially their only tradeable commodities. As world consumption of oil has grown over this past half century, the populations of these countries have literally exploded. In many of them over half the population is under twenty years of age. When those oil resources go into serious decline, if they are not on the front edge of that predicament already, the means of support for that tremendous population will disappear. Most of these nations have a policy of being as self sufficient in food production as possible, but water limitations, despite their draw down of aquifers at three times the renewal rate and considerable investment in desalination facilities, have kept them from achieving self-sufficiency.[15] Saudi Arabia, in fact, are doing significant Promotion of the use of saline water and salt-tolerant species to increase food and feed production.[15] To date the lack of food self-sufficiency has not been a problem for these countries because they have had the income to trade for what they can't produce. As the oil revenues begin to disappear, however, the potential for revitalizing age-old conflicts in the region are of serious concern.

Complicating all of the real issues involving water sharing is the fact that water has become the most commercial product of the century. Water is to the 21st century what oil was to the 20th century.[8] Water has been put on the table as a tradeable commercial product in almost every bilateral and multilateral trade agreement negotiated during the rampant growth of commercial globalization. Many weaker countries are being pressured into putting their scarce water resources up for grabs in order to achieve other gains in these trade agreements. Even Canada is under considerable and constant pressure from the U.S. to put the country's considerable fresh water resources at the disposal of commercial interests. Canadian water and the shared water resources of the Great Lakes basin are consistently viewed in Washington and Many U.S. state capitals as the solution to growing water scarcity in that country's heartland.

The impact of climate change on the redistribution of water resources further adds to the complications that threaten to contribute to future conflict. In some areas longstanding water resources, like many of the lakes in Africa, are drying up while other areas, such as much of Europe, are experiencing unprecedented flooding. Areas like the U.S. midwest, one of the world's foodbaskets, are drying up with perpetual crop losses driving more and more producers into bankruptcy. Extreme weather events are on the increase as the planet warms. All of these things affect the amount of water available to agriculture. The global emergency food grain reserves over this past decade have shrunk from a marginal 119 day supply to a very critical 53 day supply, and continues to decline by 2-4 days supply per year.

There is little question that the growing global water crisis has the potential to be one of the key sources of conflict between nations, and even within nations, over the balance of this century and beyond. Considering the political difficulties that have accompanied the drafting, writing and signing of existing international freshwater agreements (most not during times of critical water scarcities) future agreements will become increasingly difficult to finalize and consistently open to abuse by the signatories.
=========================
The following were key sources of material for this article;

1) IJC Releases Statement on its Review of Lake Ontario and St. Lawrence River Regulation
2) United States & Canada International Joint Commission Public Interest Advisory Group Public Meeting
3) Long Sault to Beauharnois: the St. Lawrence River restructured
4) Robert H Saunders Dam (before 9/11) and Dwight D Eisenhower Lock in Massena, N.Y.
5) The Lost Villages
6) Lake Ontario St. Lawrence River Regulation
7) Lake Ontario–St. Lawrence River Framework Data Project examines ups and downs of water levels
8) Water crisis looms in countrywide
9) Atlas of International Freshwater Agreements
10) The World.s International Freshwater Agreements: Historical Developments and Future Opportunities[PDF]
11) A Compilation of All The International Freshwater Agreements Entered Into by South Africa With Other States
12) The International Joint Commission and the Great Lakes Water Quality Agreement
13) International Shared Aquifer Resource Management (ISARM)
14) Internationally Shared Aquifer Resource Management: ISARM AMERICAS
15) Role of Biosaline Agriculture in Managing Freshwater Shortages and Improving Water Security
16) World Water Council: Water Crisis
17) Water in the Earth's atmosphere
18) Why is the Ocean Salty?

July 18 Presentation at Bloomfield, Prince Edward County, Ontario

Peak Oil, Climate Change and Local Sustainability

Peak oil is the theory that we have or are about to have used up half the world’s endowment of oil and that what oil remains will be increasingly scarce and unavailable, steadily poorer quality, and increasingly more expensive. IT IS NOT a theory that we are about to run out of oil.



Global warming is the theory that man-made atmospheric pollution, mostly from the burning of fossil fuels, is causing the earth’s atmosphere to heat up to potentially dangerous levels.


Global Dimming is the theory that air born particulates, mostly from man-made pollution, are reducing the amount of the sun’s light and energy that are reaching the earth’s surface.



Overpopulation is the theory that total human population is exceeding the real carrying capacity of the planet.



I could speak for a whole hour on any one of those looming crises, but I won’t. My purpose here this evening is to try to encapsulate in a half hour or so how in this century the merger and interrelationship of those four crises, and a few other peripheral and related crises such as water, are going to affect;

* Food Security,
* Carrying capacity,
* Soil Fertility,
* Sustainability,

Both globally and, more important, locally here in Ontario and in Prince Edward and surrounding counties.

A few words about energy consumption;

* Global energy use per capita has risen more than 10 fold since the start of 20th century.
* One energy source has not replaced another, each is treated as an add on to the energy mix, resulting in layered energy options.
* Each of us uses the energy equivalent of over 300 slaves.
* Food on your table has traveled an average of over 2500 kilometers.
* The greater the energy use, the further removed we get from sustainability and self-sufficiency.
* This century we will hit not only peak oil but peak natural gas, peak coal, peak uranium, peak plutonium, as well as peaks in dozens of other finite resources; copper, gold, nickel, selenium, zinc, molybdenum, & more.

See my blog articles, Energy as the Catalyst in the Punctuated Equilibrium of Human Population Growth and Alternative Energy, Add-ons and Replacements

There is a not so old Saudi saying that prophetically encapsulates what we are facing in the near future with energy. It goes;

"My father rode a camel. I drive a car.
My son flies a jet-plane. His son will ride a camel."

The most critical and dangerous dependence on fossil fuels we have built is in food production and distribution. We use an average of 10 calories of energy, mostly from fossil fuels, to produce 1 calorie of food.

Despite the fact that we share it, albeit reluctantly, with millions of other species, the human population monopolizes over ¼ of the primary food production capacity of the planet. There is obviously considerable capacity still available to us, but only if we want to be alone. Our increasing monopoly of that primary productive capacity directly parallels the increase in human-caused species extinction. That doesn’t make us particularly evil. The dominant species in any environment always takes what it needs leaving weaker competition to fight for the scraps.

For the moment, then, let’s forget about those millions of other species. What exactly is the carrying capacity of the planet?

* Of the total global land mass, about 35% is arable land, 31% forested and 34% is either desert, tundra/permafrost or dedicated to other human uses such as urbanization or activity such as mining or recreation.
* Globally there are about 7.8 billion acres that are potentially arable of which 3.5 billion acres are now being used to produce food.
* The unused potential land is generally in areas lacking essential transport for moving product to market or infrastructure needed for the support of commercial food production.
* Of the 35% of the total global land mass that is arable or suitable for agriculture, about 2/3 is pasture or meadowland used for livestock.
* Another 10% (about 350 million acres) is used for grain and cereal production, much of that (75% or about 270 million acres) also used for livestock.
* Despite the global attraction of and growth in permaculture, only 1 percent of arable land is dedicated to permanent crops such as fruits and nuts.
* Essentially, all of human food production, excluding meat, dairy and sea food, is grown on less than 400 million acres. Each of those acres is, therefore, feeding about 15-17 people.
* If we were to bring all of the unused arable land into agricultural production with the same patterns as at present (85%+ for livestock support) we would net very little additional food-production land (about 600 million acres) to offset the anticipated drop in productivity of 80-90% on those current 400 million acres following peak oil. This would barely allow us to absorb the impact of a 25% drop in productivity.
* The unused potentially arable land is not in the same place as the 6.6 billion of us for whom it could reduce the impact of soil productivity loss following peak oil. It exists in pockets within the boundaries of already sovereign nations throughout the world, nations which themselves may be impoverished and unable to currently produce enough food for their own people.
* Probably, based on current patterns, these lands would more likely be used for high-profit crops like corn, soy and sugar cane to be used to produce bio-fuels in a world increasingly deficient in fossil fuel energy.
See my blog article, Post-Peak Agricultural Capacity

Global Water
We are very fortunate in Canada, exceptionally so in southern Ontario. Canada in general and southern Ontario in particular should be able to avoid the fresh water issues that will face much of the rest of the world this century and in the foreseeable future. The water rights issues that plague many drier areas such as Africa, South Asia and the western U.S. are and will be only an occasional problem in this area.

* Canada has the third highest volume of renewable fresh water in the world behind Brazil and Russia.
* Canada has more lake area than any other country in the world.
* The Great Lakes are the largest system of fresh, surface water on earth, containing roughly 18 percent of the world supply.
* Ninety-nine percent of surface freshwater by volume is in lakes and only one percent in rivers.

That is not to suggest that anyone should be complacent about water. Ultimately fresh water availability nets down to a resource issue for a single property, a single family, a single community. In essence, if you need it and you don’t have it or don’t have access to it, it is a serious problem for you.

* More than 2,200 major and minor water-related natural disasters occurred in the world between 1990 and 2001. Asia and Africa were the most affected continents, with floods accounting for half of these disasters.
* Of the dozens of water rights conflicts around the world I have read about and researched almost always agricultural water needs and water rights have lost out to the demands of urban areas and industry.
* Whenever the resolution of water rights conflicts is left in the hands of politicians and bureaucrats the resolution will be decided in favour of the highest voting density and financial contribution.
* The U.S. are moving inexorably toward solving the water needs of their agricultural and industrial heartland through the southward diversion of the waters of the Great Lakes. Considering the massive engineering project this would involve, peak oil could be a blessing in disguise.
Statistics from How much do we have?

Continued net decline in soil productive capacity

We are systematically destroying the overall fertility of our soil and losing productive soil.



* Our use of agricultural pesticides kills critical soil organisms,
* Intensive deforestation results in losing billions of tons of top soil,
* Annual U.S. topsoil loss is 7 billion tons (23 tons/year/person, 85% directly attributable to raising livestock),
* Intensive irrigation leaches vital mineral content out of topsoil,
* Air pollution results in toxic chemicals being absorbed into the soil,
* Industrial scale plowing and tilling results in billions of tons of top soil being dried up and blown away every year,
* We create an impermeable layer of hardpan just below the top layer of soil which prevents both plant roots and soil microorganisms reaching the mineral nutrients in the subsoil,
* Turning the soil exposes deep topsoil organisms and drives aerobic microorganisms deeper underground where they are killed for lack of air, water and heat from sunlight,
* We systematically destroy balance of soil nutrients through continued application of artificial NPK fertilizers,
* We change soil ph levels making it inhospitable for many soil organisms,
* We change symbiotic relationship of soil organisms and plants by replacing native plants with chemical-dependant monoculture.
* Soil erosion and other forms of land degradation now rob the world of 70-140,000 km2/year of farming land.
* Urbanization alone is responsible for the loss of 20-40,000km2/year.
* Worldwide, soil erosion has caused abandonment of 4.3 million km2 of arable land during the last four decades.
* The total world availability of topsoil is estimated at 7,000 gigatonnes - about seventy years of topsoil at current rates of destruction and loss.

State of global food production, consumption, distribution
* Before the Industrial Revolution the majority of people produced most of their own food, most of the rest acquired within a few miles of home.
* People then ate what could grow locally and ate what was in season or that they stored/preserved themselves. Now we eat tomatoes and celery in February, kiwi fruit and spring lamb from New Zealand, oranges from Israel, rice from the far east, beef from Argentina.
* The vast majority of people in the developed (and increasingly in the developing) world today who are growing food (now less than 2% of population) are not doing so for their own consumption.
* Agricultural produce today is fed into a heavily fossil-fuel dependant global food distribution system.
* Food today travels an average of 2500+ kilometers before reaching your table, takes a week, often much longer, to get there.
* Average food miles continue to grow with spread of urbanization and corporate-driven regional crop concentration.
* Food grown locally will be available in local food stores only by chance after having worked through the distribution system.
* Today more than ½ of global population live in cities, most with severe restrictions standing in the way of producing their own food.
* Most cities originated in and continue to expand into the very farmland they need to produce the food needed by their populations (urbanization responsible for loss of 20-40,000km2/year of arable land).
* The majority of people engaged in agriculture today are working land they do not own to produce product they do not, and cannot afford to, consume themselves.
* About 85% of “productive” agricultural land today is devoted to the support of livestock.
* The average diet today contains more meat and animal products in one day than our ancestors consumed in a week.
* Global emergency food grain reserves have shrunk in past ten years from marginal 119 day supply to a sub-critical 53 day supply.
* Ever increasing proportion of global food coming from GMO crops, an increasing use of terminator genes to ensure ongoing seed co. sales.
* Multinational corporations decide what is grown, how its grown, what is available in your local market (stocking decisions not made locally).

Understanding plant nutrition
Plants receive their nutrients through and digest their food, like you, in their stomachs. The topsoil in which a plant grows is, in reality, its stomach. The stomach is an organism’s nutrient supply buffer between the outside world and the critical internal systems. Whole foods are broken down by bacteria and enzymes into pure form suitable for transport through those internal systems, like our blood stream, to the cells and organs which need those nutrients for metabolism and maintenance. Enzymes intercept toxins and eliminate them before they can enter those internal systems. A glut of nutrients is buffered and released slowly to those internal systems.

For a plant, all of these functions happen external to its critical internal systems. Bacteria and enzymes in the topsoil, especially that narrow band of topsoil immediately around the roots, the root zone, do this work. The roots themselves, to continue the parallel, are like the portal vein leading from the small intestine to the liver. It is the last part of the digestive system external to the organism’s sensitive internal systems. The root zone is like the small intestine, releasing the broken down essential nutrients to the roots (the portal vein) for absorption into the internal systems.

Just as the digestion in your stomach is under the control of your internal systems (principal digestive enzymes are generated in your pancreas and released into the stomach) the “digestion” for a plant in the soil is under the control of the plant in that the principal digestive enzymes are generated internally and released into the root zone.

See my blog articles, Plants with stomachs - Peak oil implications and Plant stomachs and animal stomachs: the differences and similarities

Topsoil as a living organism
Just like your skin is the largest organ of your body, the topsoil may be the largest living organism on the planet.

A single pound of soil contains tens of millions of bacteria, fungi and other soil microorganisms critical to the survival of all terrestrial life. Many of these microorganisms can trace their family tree (pardon the pun) all the way back to the very beginning of life on earth.

Nature wastes nothing. Those microorganisms are responsible for breaking down the raw resources in the soil and beginning the process of cycling it through the web of life, whether that resource be a fallen tree, a dead animal, a pile of elephant dung, a cow’s placental sack, or the minerals in a rock that has worked its way up from the subsoil.

We have, unfortunately, put a large portion of our planet’s topsoil on force-fed chemical life-support with our use of artificial fertilizers, pesticides, herbicides and other agrichemicals, like a brain-dead patient on intravenous life-support. We are destroying the natural fertility of the soil in the process. Just as it takes time to put a coma-recovery patient back on solid food (like weaning an infant off the bottle), it will take considerable time, possibly decades, to restore the natural fertility of soil that has been chemically maintained for decades.

When we remove life-support from the coma patient that patient generally dies relatively quickly. What will happen to our agricultural productivity when we pass peak oil and the agrichemicals begin to disappear? When we pull the plug on our soil’s artificial life-support?

Building/Maintaining Natural Soil Fertility
You’ve just picked a bunch of carrots. Consider what they are composed of;

* Water from the soil (maybe from rain or maybe irrigation),
* Hydrogen (in the carbohydrates) mostly from the water,
* Carbon, partly from CO2 but also from the soil,
* Other minerals like iron, sulfur, phosphorus, potassium from the soil,
* Fiber, collagen and vitamins like beta carotene produced by the plant from nutrients derived from the soil.

For most people the top of the plant ends up as “plant waste“. Before the carrot is eaten the root hairs and possibly the skin is pealed, more plant waste. The carrots are washed, the dirt flushed away. The carrot may be cooked, many nutrients lost into the cooking water which is discarded.

Generally none of this “wasted” plant material makes its way back to the soil in which the carrot was grown. The entire mass of that plant that was derived from the soil is a net loss for that soil.

We cannot continue to take organic material from the soil and replace it with a limited range of artificial nutrients (NPK) and expect that soil to remain viable. If we lose 100 billion tons of topsoil every year through erosion, how many billion tons or topsoil mass do we lose every year in food that we harvest from it? Artificial fertilizer use has grown 33-fold over the course of the Green Revolution in an unsuccessful attempt to maintain crop yields. And that usage will continue to grow, and still not maintain topsoil mass.

If we do not begin or resume returning to the soil what we take from it, we will continue to deplete the topsoil at a far greater rate than nature alone can replace it. Just as with any other resource, if we use it faster than it is being replaced it can eventually run out. We have broken the cycle. We must reconnect it.

As you drive around country roads take a look at the fields that have been in long term use for producing cash crops. Compare the depth of the soil in those fields to the depth of that surrounding those fields. The difference is mostly a combination of three things;

1) Soil compaction through the use of heavy farm equipment;
2) Soil loss from wind and water erosion;
3) Most important, continual loss of soil mass from crops being harvested and the “waste” organic matter not being returned to the soil.

I’m not sure if there are any examples around here but around cities like Toronto, when they build a subdivision, the first thing they do is strip all the top soil and pile it up in a big hill. From there it may be sold to a jobber to be “cleaned”, bagged and sold in garden centers.

When the homes are completed the top soil that was stripped (it may have been a foot deep) is replaced with grass sod that may have as much as a whole inch of soil held by the grass roots. Homeowners go to the garden center to buy bags of topsoil (it may have actually come from the land on which their house sits) to build their flower gardens.

On the other side of peak oil when the global food distribution system begins to break down, the chance of growing any significant amount of food on suburban plots is slim and none.

Soil fertility consists of a number of key factors; carbon, other trace minerals, organic content, humus, soil microorganisms, water.

Liebig’s Law of the Minimum says that growth is controlled not by the total resources available but by the scarcest resource. When a plant consists primarily of carbon and carbon-based molecules, how can we believe that fertilizing with Nitrogen, Phosphorus and Potassium is going to allow us to maintain yields and soil mass?

You restore and maintain natural soil fertility by building and continuing to nurture and replenish; carbon, other trace minerals, organic content, humus, and soil microorganisms.

Carbon
There is a soil type in the Amazon region of South America that has been receiving considerable scientific attention. It is called Terra Preta soil. It has been determined that this soil, as it is now constituted, is man-made. There are two keys to Terra Preta soil; 1) high carbon content, 2) a unique community of soil bacteria. The carbon in Terra Preta soil, it has been determined, originates from charcoal created as part of an ancient slash and char method of soil preparation. Terra Preta soil will net a yield of 300-800% that achievable in adjacent non-Terra Preta soil. Though it is thought that the unique soil bacteria is the more important component, black carbon soil supplementation alone has been proven to be very beneficial to soil and significantly improve yields, shorten required fallow times, improve soil water retention, reduce soil toxicity levels, and encourage growth of beneficial soil microorganism populations. Terra Preta soil, by the way, has also been found and proven to be self-renewing.
See the articles Terra Preta Soils - Agricultural Miracle from the Past? and Origins of Amazonia's Terra Preta Soils in my blog

Other trace minerals
The minerals in the soil largely originate from the base rock below the soil. That base rock is very slowly broken down by plant roots and soil microbes. In a natural system the minerals from the soil are constantly recycled by living organisms. In our unnatural agricultural systems minerals taken up by plants (they are used as critical co-factors in enzymes and hormones, in the formation of chlorophyll, in the structure of vitamins and more) is lost to the soil as those plants are removed in harvesting. Organic farmers often dust their fields with rock dust and other sources of trace minerals to replace minerals removed from the soil in harvesting. Bags of these materials can generally be purchased at garden centres and farm supply outlets.

Organic content and Soil Microorganisms
There are, of course, several traditional ways to return organic matter to the soil; using manure fertilizers, fallowing, planting and plowing under green manure crops, and composting. With the demands for maximum crop yields most of these practices have been abandoned in commercial farming operations. This is the most critical change that has to occur in revitalizing our soil fertility. Critically important is that all of these practices have a dramatic impact on the growth and health of the population of soil microbes. Organic content in the soil is also the most critical factor in the ability of the soil to maintain moisture, thus minimizing demands for irrigation.
See my blog article Soil fertility and carrying capacity

Post-peak Community versus homestead
The vast majority of people who become aware of the peak oil issue soon begin to consider the question of what type and size of community they want to be part of beyond peak oil, which communities will be the most sustainable, self-sufficient, self-reliant and survivable in the future.

The answer to that question is tremendously variable for a number of factors such as climate but most particularly depending on how far into the future one is thinking.

I cannot, in the time I have available, do justice to this issue. I would strongly suggest that you see a number of articles on my blog, Oil, Be Seeing You dealing with the issue;

* An argument against personal peak-oil preparation
* Homestead or community?
* Is there any alternative to powerdown? And the sooner the better?
* The right to pursue powerdown: seeking alternative lifestyles post-peak
* Relocalization and retail food chains

Essentially my belief is that it is critical to build strong, viable, self-sufficient and self-reliant community in preparation for the fast-approaching post-peak world. That community and its self-reliance critically includes all agricultural efforts in and around the community. The type of world in which our ancestors scratched self-reliant homesteads from the wilderness simply doesn’t exist anymore. The feeling for it may be strong in certain individuals but it has entered the world of myth.

Ideally post-peak community focuses on a bio-region. As I mentioned earlier, Prince Edward County is a very viable natural bio-region. The prospects of creating the self-reliance and self-sufficiency that will be the hallmark of successful post-peak communities is very strong here.

* There has been a strong build-up of a community of artisans and craft-persons with the type of skills that will be strong components of a post-fossil-fuel community.
* The county is effectively surrounded by water resources that should remain viable into the future.
* The Trent water system continues to deliver vital soil nutrients.
* The climate of the region is tempered by the water surrounding it.
* There is a strong agricultural tradition in the county, as well as a significant core of organic agriculture.
* The sizes of all communities in the county is conducive to building a regional network of self-reliant communities with a rational distribution of specialized skills and crafts.

The type of community that will be suited to the post-peak world, however, does not just happen. In our modern world the feeling and spirit of community, even here, has largely been lost. It will be critical to determine the skill sets that will be needed and ensure that those skills are built.

I could go on at length on this subject but it is important that you address this. The community has to be built from within. Local initiatives like the proposed establishment of a local farmer’s market, which I urge you to support, will be what makes the difference.

What you can/should do to prepare for the future
* Take care of whatever soil you have access to, maintaining soil fertility
* Ensuring access to clean water
* Understand sustainability and stewardship
* Forest management, plant trees, preferably hardwood, replace any harvested trees in kind
* Soil testing, classification, integration
* Root cellars, dehydrating, canning, smoking, drying, freezing
* Support local food production, 100 mile diet, 50 mile diet
* Heritage seeds, seed saving, surpluses
* Permaculture, three sisters, companion planting and other food production techniques
* Big and small islands - Bioregionalism and it's local applicability, relocalization
* Evaluate potential applicability of local currency
* Reduce consumption of animal products: meat and dairy especially; indoor food growing; public education and information exchange on sustainability within the community

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]
---------------------------------------------------------------------------------
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