[Terrapreta] Earthen Kiln Conjecture

[Kevin Chisholm]

Dear Max

Good questions!! I don't have such information.

One thing that would be very interesting also would be to learn if 
anyone has actually re-assembled a pot/container from the shards found 
on the TP sites. If sufficient related shards have not been found to 
re-assemble a pottery piece, is there enough information about pottery 
shard shape to infer that it came from a bowl, a pot, a urn, a roof 
tile, etc?

One could probably infer from the average size if the shards were 
"accidentally broken, or purposely broken".

Best wishes,

Kevin

MFH wrote:
> Kevin
>
> Do you (or anyone else) have any data on:
>
> a) the average size of the char pieces in the TP soil in the Amazon
> b) the largest piece recorded to date, and
> c) the smallest
>
> Thanks, Max H
>
>
> -----Original Message-----
> From: terrapreta-bounces at bioenergylists.org
> [mailto:terrapreta-bounces at bioenergylists.org] On Behalf Of Kevin Chisholm
> Sent: Thursday, 17 April 2008 8:18 AM
> To: Robert Klein
> Cc: terra pretta group
> Subject: Re: [Terrapreta] Earthen Kiln Conjecture
>
> Dear Robert
>
> Robert Klein wrote:
>   
>> Iam reposting to my blog 
>> http://globalwarming-arclein.blogspot.com/ this article by David Bennet
>>     
> with Lehmann on Terra Preta in2005.  This reconfirms the most
> criticalinformation as well as describes the original scope of the Indian
> civilizationitself.Againthis lays out the limiting factors and fully
> supports my earthen kilnconjecture.
>
> I like your Earth Kiln Conjecture, in that it sets out a possible 
> explanation for the presence of charcoal in TP areas.
>   
>>  Firstly,the maize or corn exists in an environment that mitigated against
>>     
> its use forpurely food production.  There werealternatives far better
> suited. to the non terra preta environment, startingimmediately with manioc
> which is a rainforest friendly plant.
>
> See: http://www.davidparsons.net/Milpa/M_intro.html, that describes the 
> Milpa System of primitive agriculture as is presently practised in parts 
> of the Yucutan and Belize. Basically, a space is cleared in the jungle, 
> and "The Three Sisters" (Maize, Beans, and Squash) were planted. This 
> system works, and is simple but labor intensive, due to the need to 
> clear new land every year. I would pose that Milpa was the original 
> agriculture system, and that it evolved into the Terra Preta system, 
> that did not require annual clearing of jungle for one crop and then 7 
> to 20 years of fallow. In summary, the addition of char to a Milpa Plot, 
> would allow addition and retention of additional nutrients, to enhance 
> growth.
>   
>> Secondly,the only viable source of meat protein to these peoples at this
>>     
> populationdensity was through fish.  Withoutconfirmation, a pond with
> tilapia makes great sense. The waste from the dailymeal could be readily
> folded into any growing seed hill.  Human waste could simply have been
> buried inthe field itself avoiding any storage. 
>   
>>   
>>     
>
> Such a system would make sense in the context of smaller, dispersed 
> villages. The important thing is that large villages and communities 
> start from small villages and communities. Aquaculture was practised in 
> Chile or Peru, where fish were grown in the irrigation channels in the 
> sides of mountainous terrain, where there was the grade for water 
> conveyance. A key thing was that such "fish water" conveyed both 
> phosporous and potassium to the plants, in addition to the water. 
> Tilapia are a very special fish, in that they can live on algae. Algae 
> growth can be promoted by addition of manure to the irrigation water, 
> and the Tilapia can grow under "green water conditions", as is employed 
> in SE Asia Pond Culture. In larger communities, the field irrigation 
> channels would provide a very convenient way for disposal of night soil.
>   
>> This is common practice to this day.Themaking of the earthen kiln is no
>>     
> more difficult than uprooting the dehydratedcorn stalks and properly
> stacking them to form an earthen walled kiln with awall thickness of two to
> three root pads and an interior of tightly packed cornstalks.
>
> Given that the Primitive Farmer went to all the work of  clearing a hole 
> in the Jungle, and given that he had one good year with a bountiful 
> harvest, it would be a natural step to try and avoid the extra work 
> required to clear more Jungle, to continue with the cropping/fallow 
> cycle. It would be a lot easier to pull the maize stalks and stack them 
> as you suggest, to dispose of them in an attempt at getting another year 
> out of a particular Milpa Clearing. The Milpa System employs fire as a 
> "clearing aid", and in the attached photo, charcoal is evident.
> http://www.davidparsons.net/Milpa/M_practices.html.  Note however, that 
> with the Milpa System, the exposed sticks and stalks would generally 
> burn to completion. However, with Robert's Earthen Kiln Hypothesis, the 
> "root ball walls" would tend to collapse onto the partially 
> burned/charred corn stocks, smothering the fire, preventing it from 
> going to completion, and thereby producing a much higher yield of  
> residual char than would an open bonfire.
>   
>>   Obviously, any other plantmaterial, including wood can be built into the
>>     
> stack as available.  The earthen wall nicely restricts air flowduring the
> burn phase and lends itself to optimization by changing thethickness.  It
> also minimizes the amountof human effort needed which is through the roof if
> you are attempting to covera pile of stubble or branches.Thisgives you a
> kiln with vertical earthen walls and a possibly domed top that canbe easily
> covered with earth.  Again,field trials will optimize this protocol very
> easily.  The kiln could be squared of or perhaps even circularthough
> unlikely. The only tool to this point is a strong back or two. 
>
> Nowadays, the Milpa Farmers have the benefit of steel machetes, and 
> would be able to easily cut the stalks from the root ball. Without a 
> machette, it would be much easier to pull up the entire stalk, and stack 
> the stalk and root ball in the manner suggested by Robert. Certainly, 
> the incremental effort to pull and stack the stalks would be less than 
> the effort to move to another site and clear more jungle.
>   
>>  We have gathered several tons of
>>  corn stoverover perhaps an acre of land with only a little more effort
>>     
> than that requiredto clear the field and burn the waste.Nowwe must fire the
> kiln.  The easy way isto take a clay lined old basket and fill it up with
> coals from a woodfire.  Carry this ember charge to thecenter of the kiln top
> and tip the charge onto the exposed center and place thebasket as a cap to
> the newly forming chimney. 
>   
>> More clay may be necessary to widen the chimney cap.  Throw more earth on
>>     
> top of this to preventbreakout of the fire.  Keep growing earthon any
> breakout points that start.  Thechimney will serve to burn all the volatiles
> produced as the hot zone expandsto fill the collapsing kiln until they are
> exhausted. 
>
> If the Farmers were simply trying to get rid of vegetative waste, to 
> avoid opening up new Jungle, then they may not have been very interested 
> in plugging up any air leakage points. Less labor would be involved is 
> simply "stack and burn", rather than tending the earthen kiln. They had 
> no need to burn the volatiles to completion. Indeed, the smoke would 
> probably be beneficial, through dispersing mosquitos and insects.
>
>   
>>  Thereupon the hot zone will cool off leavinga blend of biochar, ash and
>>     
> earth and some root ends for the next kiln.  And yes, we should have a lot
> of fired clay.
>
> This is very interesting. Loose earth from the rootballs would not be 
> compacted sufficiently to yield the pottery shards we now associate with 
> Terra Preta. However, the process could very well have produced 
> "microshards" of "pottery". Actually, this "fired soil" would not be 
> "microshards", in that the term "shard" usually refers to "broken pieces 
> of pottery", and it would not be "pottery", in that the term usually 
> refers to "a formed clay shape that was fired to enhance its 
> properties." It would be expected that this would be a "low temperature 
> firing", and it is thus not likely that the "fired root ball pottery 
> particles" would be able to endure the ravages of 500 to 4,000 years of 
> tropical weathering.
>   
>> Thebiochar itself will be a range of nonvolatile combustion products that
>>     
> willrange from even dried vegetation to activated charcoal following a nice
> bellcurve.  The material can be then gatheredin baskets and redistributed
> into the field onto the seed hills again reducingwastage and
> effort.Irealized originally that the only ancient plant that could
> accommodate a highenough volume of terra preta production was good old
> maize.  It just seemed an unlikely option fortropical rainforests. That is
>   
>>  when I started looking for references to thepollen record.  The article
>>     
> by DavidBennett and Lehmann is one of those reverences that then
> emerged..Iwould like to get a full spectrum of the pollen profile since it
> seems verylikely that while the fence rows held the food trees, it seems
> more likely thatthey also used a variation of the three sisters using some
> form of convenientlegume.  Squashes also, of course, butnot nearly as
> important.Thekey point of all this is that a family can convert a field into
> terra preta inone short season, allowing them to repeat the process
> thereafter as necessaryuntil the field is completely transformed to depth.
> Today, we can do the same thing using shovelsand a garbage can lid.   Terra
> preta: unearthing an agriculturalgoldmineNov 14, 2005 10:36 AM, By David
> Bennett
>   
>>   
>>     
>
> In http://www.davidparsons.net/Milpa/M_threats.html, there is reference 
> to "insufficient period of fallow". It would indeed be advantageous to 
> be able to extend the productive period of a Milpa, to avoid the need to 
> clear more jungle. Weeds are a problem in a fertile soil. What they 
> needed for sustained cropping of a given milpa area would be
> 1: A mulch system, that focused growth where they wanted it, and
> 2: Plant nutrients.
>
> Now, people don't live in the fields where they are attempting to grow 
> their food crops. They would live adjacent to their fields. They would, 
> of course, be producing Nightsoil, and naturally, they would need to 
> dispose of it. Fresh manure and night soil could damage the crops. For 
> the simple reason of smell, it would make sense to have adjacent fields 
> working on "short fallow system"... crop one field area, while applying 
> the humanure to an adjacent area. This would allow pathogens the time to 
> degrade to a safe level. An additional "health protection benefit" of 
> the "Three Sisters" is that they are all "above ground crops."
>
> They had pots made of "pottery", and these pots over time would break. 
> It would not take long for a Farmer to discover that pottery shards make 
> an excellent mulch, in that plants do not grow up through pottery 
> pieces. A further benefit of such pottery mulch is that it is fireproof. 
> It would be a relatively easy thing to simply "burn the weeds". A 
> further benefit using such a "fireproof mulch" is that there would tend 
> to be moisture retention below the shards, and this moisture would tend 
> to prevent loss of organic material from the soil. Fire burning of the 
> weed tops with pottery shards as a "fireproof mulch" would result in an 
> increase of organic material in the soil, from the weed root system.
>
>
>   
>>  
>> Many soil scientists insist an ancient Amerindian agrarian society will
>>     
> soon
>   
>> make a huge impact on the modern world. They say once the intricacies and
>> formulation of the society's "terra preta" (dark earth) is unlocked, the
>> benefits will help stop environmental degradation and bring fertility to
>> depleted soils. Developing and developed nations will benefit.
>>   
>>     
>
>  Milpa and Terra Preta were NOT "systems designed to prevent 
> environmental degradation... they were systems designed to provide a 
> supply of wholesome food on a regular and dependable basis. Certainly, 
> obvious signs of "environmental degradation" would be dealt with, and 
> the one concern I could see that they would have is loss of soil through 
> erosion. Flat pottery shards would absorb the energy of falling rain, 
> and reduce soil erosion problems.
>   
>> Orellana
>>
>>
>> The story goes that in 1542, while exploring the Amazon Basin near Ecuador
>> in search of El Dorado, Spanish conquistador Francisco de Orellana began
>> checking the area around one of the Amazon's largest rivers, the Rio
>>     
> Negro.
>   
>> While he never found the legendary City of Gold, upon his return to Spain,
>> Orellana reported the jungle area held an ancient civilization - a farming
>> people, many villages and even massive, walled cities.
>>
>>
>> Later explorers and missionaries were unable to confirm Orellana's
>>     
> reports.
>   
>> They said the cities weren't there and only hunter-gatherer tribes roamed
>>     
> the
>   
>> jungles. Orellana's claims were dismissed as myth.
>>
>>
>> Scientists who later considered Orellana's claims agreed with the negative
>> assessments. The key problem, they said, was large societies need much
>>     
> food,
>   
>> something Amazonia's poor soils are simply incapable of producing. And
>>     
> without
>   
>> agriculture, large groups of people are unable to escape a nomadic
>>     
> existence,
>   
>> much less build cities.
>>   
>>     
>
> Milpa could very well progress to Terra Preta, and with the sanitation 
> requirements for larger communities, there could very well have been a 
> food system that evolved to support it. A classic symbiotic relationship.
>   
>> Dark earth
>>
>>
>> More recently, though, Orellana's supposed myths have evolved into
>>     
> distinct
>   
>> possibilities. The key part of the puzzle has to do with terra preta.
>> It turns out that vast patches of the mysterious, richly fertile, man-made
>> soil can be found throughout Amazonia. Through plot work, researchers
>>     
> claim
>   
>> terra preta can increase yields 350 percent over adjacent,
>>     
> nutrient-leached
>   
>> soils.
>>   
>>     
>
> There is absolutely no mystery or miraculous occurence here... plants 
> grow well in nutrient rich soil and they grow poorly in nutrient poor 
> soil. With all the burning and vegetation, it would be natural for some 
> of the Milpa  Farmers to have noticed that  black soil seemed to last 
> longer before yields fell off to the point that a fallow period was 
> necessary. These Farmers were primitive, but they weren't stupid.
>   
>> Many well-respected researchers now say terra preta, most of it still
>>     
> hidden
>   
>> under jungle canopy, could have sustained large, agronomic societies
>>     
> throughout Brazil and neighboring countries.
>   
>>   
>>     
>
> The "well respected researchers" don't deserve much respect, if all they 
> can say about Terra Preta is that
> "... it could have  sustained large agronomic societies...". They would 
> deserve much more respect if they provided more insight into Terra 
> Preta. :-) The above statement may have some profound content...
> "... terra preta, most of it hidden under Jungle canopy..."  Is it 
> perhaps possible that terra preta is simply the natural jungle soil?
>   
>> Amazing properties
>>
>>
>> The properties of terra preta are amazing. Even thousands of years after
>> creation, the soil remains fertile without need for any added fertilizer.
>>     
>
> This is a stretch. A very big stretch. It goes against all known 
> "Agricultural Paradigms". Mother Nature is very strict with her rule 
> "You never get something for nothing." The above statement would only be 
> true if a fertile, nutrient laden soil was not used for growing, or if 
> nothing was removed from the site as crops, or through leaching, or as 
> food for soil organisms, or as an oxidation product...
>   
>>  For
>> those living in Amazonia, terra preta is increasingly sought out as a
>> commodity. Truckloads of the dark earth are often carted off and sold like
>> potting soil.
>>   
>>     
>
> Certainly, there are people who make their living all over the world 
> bringing in topsoil, compost, and manure to areas where the soil is 
> deficient in organic matter and nutrients.
>   
>> Chock-full of charcoal, the soil is often several meters deep. It holds
>> nutrients extremely well and seems to contain a microbial mix especially
>>     
> suited
>   
>> to agriculture.
>>   
>>     
>
> Certainly, this would work. Note, however, that black soil found in a 
> wet depression could very well have been formed naturally, without the 
> presence of man-made charcoal. The soils are referred to a "Black 
> Carbon" soils, and "black carbon" can occur naturally through 
> decomposition of organic matter in anaerobic conditions.
>   
>> Thus far, despite great effort, scientists have been unable to duplicate
>> production of the soil. If researchers can ever uncover the Amerindians'
>>     
> terra
>   
>> preta cocktail recipe, it will help stop the environmentally devastating
>> practice of slash-and-burn agriculture in the Amazon jungle. Terra preta's
>> benefits will also be exported across the globe.
>>   
>>     
>
> The above passage reads well, but it doesn't say much about the caliber 
> of scientific effort being directed at figuring out how to "reverse 
> engineer" Terra Preta!! :-)
>   
>> However, even without unlocking all of the soil's secrets, things learned
>>     
> in
>   
>> the study of it are already being brought to row-crop fields.
>> Among researchers studying terra preta is Johannes Lehmann, a soil
>>     
> fertilitymanagement expert and soil biogeochemistry professor at Cornell
> University.Lehmann, who recently spoke with Delta Farm Press, says things
> learnedfrom terra preta will help farmers with agricultural run-off,
> sustainedfertility and input costs. Among his comments:
>   
>> On how Lehmann came to terra preta research.
>>
>>
>> "I spent three years living and working in degraded Amazonia field sites.
>> Inevitably, if you work in the central Amazon, you come across terra
>>     
> preta.
>   
>> "The visual impact of these soils is amazing. Usually, the soils there are
>> yellow-whitish colored with very little humus. But the terra preta is
>>     
> often 1
>   
>> or 2 meters deep with rich, dark color. It's unmistakable. We know terra
>>     
> preta
>   
>> are preferentially cropped."
>>
>>
>> On the various properties of terra preta and its modes of action.
>>
>>
>> "There are a few factors that contribute to this fertility - sustainable
>>     
> fertility.
>   
>> Remember, these are soils that were created 1,000 to 5,000 years ago and
>>     
> were
>   
>> abandoned hundreds or thousands of years ago. Yet, over all those hundreds
>>     
> of
>   
>> years, the soils retain their high fertility in an environment with high
>> decomposition, humidity and temperatures. In this environment, according
>>     
> to
>   
>> text books, this soil shouldn't exist.
>>
>>
>> "That alone is fascinating for us.
>>   
>>     
>
> Amazonian Jungles have been in existence for much longer than the 
> presence of Man in Amazonia. They are a natural phenomenon. They work as 
> a result of the layer of humus on the surface of the jungle floor that 
> captures available nutrients and releases them to jungle vegetation. An 
> abandoned Terra Preta plot could be expected to remain fertile for a 
> very long time, PROVIDING THAT no crops were removed from the site.
>   
>> "Among the most important properties are high nutrient concentrations
>> (especially for calcium and phosphorus). Most likely, this is linked to a
>> unique utilization of agricultural and fishery waste products.
>>   
>>     
>
> Certainly, one would expect higher levels of soil nutrition in the 
> vicinity of human habitation, where they had a nightsoil and food waste 
> resource that was at the same time, a disposal problem and a tremendous 
> agricultural resource.
>   
>> "We believe that fish residues are an important portion of the high
>> phosphorus concentrations. Phosphorus is really the number one limiting
>> nutrient in the central Amazon.
>>   
>>     
>
> Near River/Lake systems, natural fish could provide a good source of 
> protein, and fish bones for fertilizer. Pond Culture may have been 
> employed further away from rivers and lakes. Human and animal manures 
> resulting from "new phosphorous" being brought into the area as a result 
> of the people "importing" foods from outside the community would also 
> result in an "above average phos level.
>   
>> "Another interesting aspect of terra preta's high fertility is the char
>> (charcoal) content of the soil. This was deliberately put into the soil by
>>     
> the
>   
>> Indians and doesn't only create a higher organic matter - and therefore
>>     
> higher
>   
>> fertility through better nutrient-retention capacity - but this special
>>     
> type of
>   
>> carbon is more efficient in creating these properties.
>>
>>
>> "You can have the same amount of carbon in terra preta and adjacent soils
>> and the infertile soil won't change. Terra preta's abilities don't just
>>     
> rely on
>   
>> more carbon, but the fact that its char and humus is somehow more
>>     
> efficient in
>   
>> creating beneficial properties. That's the truly unique aspect."
>>   
>>     
>
> This is very interesting. He might be differentiating between "Black 
> Carbon Soils" that contain "pyrocarbon" and those that only contain 
> "natural black carbon." It is also possible that on the "poor" Black 
> Carbon Soil plots, the Cation Exchange Sites on the charcoal and natural 
> black carbon may be occupied by cations that were not beneficial to the 
> plants, and thus unable to hold the nutrients that were the "bottleneck 
> to growth."
>   
>> Having lived in the Amazon and studied it, how much terra preta does
>> Lehmann believe there is?
>>
>>
>> "There are no precise numbers of how much terra preta there is (in
>> Amazonia). No one has done any large-scale investigation of that. It's
>>     
> very
>   
>> difficult to find out in the Amazon's jungle environment. Suitable
>> remote-sensing techniques haven't yet been used.
>>
>>
>> "So (the 10 percent) estimates sometimes cited are crude extrapolations
>>     
> from
>   
>> the few areas we're familiar with. But we know that in familiar areas
>>     
> there are
>   
>> huge patches of terra preta. These are hundreds of hectares large. When
>>     
> there
>   
>> have been maps produced of areas containing terra preta - say an area
>>     
> around a
>   
>> stream - patches are everywhere.
>>
>>
>> "It is also true that terra preta is widespread. Almost anywhere in the
>> central Amazon, you can step out of the car and ask a local 'Is there any
>>     
> terra
>   
>> preta around?' and they'll show you. It's everywhere."
>>   
>>     
>
> Effort should be made to determine if these Black Carbon Soils were the 
> initial result of natural black carbon formation, and if the 
> Anthropogenic contribution of charcoal to Black Carbon Soils was an 
> incidental result of working a natural black carbon soil.
>   
>> What were the Indians growing? Tree crops? Row crops?
>>
>>
>> "There has been some pollen analysis. It suggests manioc and maize were
>> being grown 2,000 to 3,000 years ago. In the pollen bank, these crops
>>     
> didn't
>   
>> pop up sporadically but in large numbers.
>>
>>
>> "But all kinds of crops were grown by the Indians. Palm trees,
>> under-story fruit trees, Brazil nut trees - all were very important."
>>
>>
>> On the differences between slash-and-burn and slash-and-char agriculture.
>>
>>
>> "We have very good indications that the Amerindian populations couldn't
>>     
> have
>   
>> practiced slash-and-burn and created these soils.
>>   
>>     
>
> This statement should be clarified. There is indeed very good evidence 
> that the Mayans in the Yucatan have indeed been practising "slash and 
> burn" agriculture on a sustainable basis for thousands of years. Milpa 
> is "slash and burn" on a patchwork basis.
>   
>> "It's also highly unlikely that a population relying on stone axes would
>> have practiced slash-and-burn anyway. The normal soils are so poor that
>>     
> with a
>   
>> single slash-and-burn event, you can only crop without fertilizer for two
>>     
> years
>   
>> at most. Then the soil has to be left fallow again.
>>   
>>     
>
> Yes, that is what the Mayans found also. This is where the addition of 
> Humanure could have led to sustained "single site tropical agriculture." 
> Additional nutrients would give immediate feedback to the Farmer, and 
> would encourage him to do it again next season"
>   
>> "Primary forest trees have a diameter of 2 or 3 meters. If all you had was
>>     
> a
>   
>> stone ax in your hand, you'd find a different way to deal with agriculture
>>     
> than
>   
>> felling these huge trees every two years.
>>   
>>     
>
> Huge trees take a long time to grow, especially in nutrient poor soils. 
> The cycle time of cropping a Milpa Site is about 7 to 20 years; 
> replacement trees would be nowhere as large as 2 to 3 meters in 
> diameter. Note that such large trees can be easily taken down by 
> primitive technology.... simply chop or burn the anchor roots and wait 
> for the first good windstorm. When the tree fell, it could be disposed 
> of by burning. These tree stems and branches could have been a 
> significant source of charcoal for the site.
>   
>> "The difference between (the two systems) is the slash-and-char wouldn't
>> burn in an open fire. Charcoal would be produced under partial exclusion
>>     
> of
>   
>> oxygen. We envision that happening by natives covering up piled up logs
>>     
> with
>   
>> dirt and straw. These charcoal-making systems are still being used around
>>     
> the
>   
>> world."
>>   
>>     
>
> In the photo referenced above, there is clear evidence of charcoal 
> having been produced, and there is no evidence of effort been expended 
> to prevent total burning of the wood.
>   
>> How close are researchers to duplicating terra preta?
>>
>>
>> "We're working intensively. We don't need to take any terra preta
>>     
> anywhere.
>   
>> What we want to do is become knowledgeable about how terra preta was
>>     
> created
>   
>> and then create it elsewhere with local resources.
>>
>>
>> "Research on this is ongoing in Columbia, in Kenya. I have research
>> colleagues in Japan and Indonesia also working on this. At the moment,
>>     
> there is
>   
>> a lot of excitement but there's a lot of work to do."
>>   
>>     
>
> It would indeed be interesting to know the avenues being pursued by the 
> various researchers.
>   
>> How terra preta could help industrialized countries.
>>
>>
>> "We envision systems based on some of the principles of terra preta. And
>> this isn't just for tropical agriculture. This could be very important for
>>     
> U.S.
>   
>> agriculture.
>>
>>
>> "Terra Preta could mean a reduction in environmental pollution. What works
>> as a retaining mechanism in Amazonia could work in the United States where
>> there are concerns of phosphates and nitrates entering groundwater and
>>     
> streams.
>   
>> We have only begun to realize the potential of how this could reduce
>>     
> pollution
>   
>> in industrialized countries.
>>   
>>     
>
> "Pollution in industrial Countries" was not a concern of the Amazonians. 
> Having a fertile soil and a secure food supply was a concern. 
> Segregating Municipal Sewage from toxic Industrial Waste should allow 
> safer and more widespread application of Municipal Sewage into 
> agricultural systems, reducing such sewage pollution
>   
>> "Luckily the principles of creating bio-char soils will be very similar no
>> matter what area of the world you're in. Results obtained in Brazil will
>>     
> be
>   
>> pertinent for the United States.
>>   
>>     
>
> One should be careful here. There are many very fertile "Black Soils" 
> throughout the world that have "Natural Black Carbon", and where there 
> is no "bio-char" that was made by a pyro process.
>   
>> "In terms of widespread adoption, it's still some way away. There are
>>     
> still
>   
>> knowledge gaps. For instance, we know there are important differences in
>>     
> the
>   
>> effects of bio-char on soil fertility depending on what material you use
>>     
> and
>   
>> what temperature and under what conditions the char is produced. That's
>> something we should be able to resolve within a year or two. Once that's
>>     
> done,
>   
>> we can take the systems to Extension Services around the world and make
>>     
> larger
>   
>> scale, on-farm research plots.
>>   
>>     
>
> Fertilizer additions seem to be an important part of the research work. 
> Little is said about the importance of fertilizers and nutrients, the 
> emphasis is primarily on the "bio-char", with little apparent 
> recognition of the importance of "natural black carbon" in the soils.
>
> Best wishes,
>
> Kevin
>
>
>
>