Page 1 of 1
Posted: Thu Jan 29, 2009 4:57 pm
Have been learing a great deal watching the conversations in the various forums. Thanks to all who share.
Wondering what the consensus is on the use of bio char in the context of NSF. On the one hand, the notion of burning organic matter seems at odds with the slash and mulch approach, but there is a level of credence seemingly placed in the product because of its ancient use in the Amazon. I'm interested in the notion that bio char does not break down like unburned organic matter and unsure whether that is a good or bad thing.
Would it make a good addition to the mulch/compost piles recommended in the nsf process? Interested in people's thoughts as much is being written about the product/process in recent times.
Posted: Thu Jan 29, 2009 5:55 pm
Wondering what the consensus is on the use of bio char in the context of NSF.
I'm not familiar with bio char, what would you recommend as a good reference to it?
Posted: Thu Jan 29, 2009 6:21 pm
I was going to get around to writing a post on agrichar/biochar.
For those of you who are unfamiliar with what it is - quick overview. Agrichar (also called biochar) is the remains of organic matter after it has been pyrolised. Pyrolisation is the burning without oxygen. The result of the process is a charcoal that is basically pure carbon with a whole lot of minerals still attached to it. This is usually ground up into small particles no bigger than wheat seeds (though size can vary).
So how is this great for our soil. Charcoal has amazing properties when mixed into soils, particularly soils low into fertilty, it does this in these ways.
1. It increases the water holding capacity of the soil enormously.
2. It increases the biota (bacteris and fungi) in the soil enormously.
3 It locks up free nutrients into the soil that only plants and soil biota can unlock. This effectively means that soils rich in charcoal don't leach out nutrients and fertility is retained - even on higher ground.
4. It increases air porosity of the soil.
the final but most significant benefit is that it locks up carbon in the soil for 1000's of years. How do we know this - because of Terra Preta soils in the Amazon which are the most fertile soils in the world that were made by man over a thousand years ago.
My firm belief is that it ties in beautifully with NSF. As the one aspect of NSF that could do with a bit more help is the capture and holding of nutrients within the soil.
I shall write some more shortly.
Posted: Fri Jan 30, 2009 12:25 pm
From what I saw on the TV with Malcolm Turnbull, the making of Biochar results in a fuel that can be burnt. Is this something like the old process of making 'Town Gas'?
Posted: Fri Jan 30, 2009 8:08 pm
When you pyrolyse organic material you produce three things. Biochar (charcoal with minerals in it), hydrogen gas and carbon monoxide gas. The two gases together are called producer gas , syngas, or biogas. They are a great form of energy which can be used to further heat the pyrolysis reaction or can be tapped off and stored for other use. Essentially town gas is the same it is just produced from coal rather than from plant material that has just been harvested.
So the beauty of biochar is that you grow some biomass, pyrolyse it which gives you energy and biochar (upto 25% of the mass). then the biochar is incorporated back into the soil where it enriches the soil and vastly improves its fertilty and water holding capacity and you grow more biomass. The end reult is a carbon negative process where the carbon is effectively locked up for good in the soil. Though the caveat here is that you still have to look after the soil you can't just let it erode away.
Posted: Mon Feb 02, 2009 9:28 am
While reading Duane's link to Stock and Land - The Farmer Wizards of OZ, I saw this link to a 3 page article on Biochar.
http://sl.farmonline.com.au/news/state/ ... 19941.aspx
I don't know about biochar, ( I was hopeless in science class in my school years) but I have often found small bits of what appears to be charcoal when digging about 8 inches down into my clay soil at home.
I have read that coal has a high water content and scientists are working on how to extract the water in a viable manner. Our coal deposits are due to natures balancing act over millions of years....yet we burn it by the tons in hours.
Posted: Sat Feb 07, 2009 9:52 am
hi there i read a small article in the stock and land about biochar recently.i am not claiming to be well read on the topic.it just doesn't sound right to me. One idea apparently is to burn up an area of forest to manufacture bio char and then turn it in and plant another forest?!?!does this sound crazy to anyone else?article also states that the quality of the biochar(as a soil improver)depends on the parent material and for some reason scientists haven't been able to replicate the original terra preta in a lab.hello! Might this have something to do with the inimitable biodiversity of the amazon rainforest?.what will the burned down forests be replaced with and what about the biodiversity that is being sacrificed in the process.of course poorer quality product can be used for fuel. So not only can we now divert cereal crop production from food to fuel but we can burn down forests as well. Tell me i'm wrong please.
Posted: Sat Feb 07, 2009 11:39 am
article also states that the quality of the biochar(as a soil improver)depends on the parent material and for some reason scientists haven't been able to replicate the original terra preta in a lab.hello!
Apparently the terra preta is anaerobic similar to a peat bog, most of our soils are not anaerobic and we don't want them to be. So the different conditions are why they can't reproduce the same result, for instance apparently biochar wont last as long in our soils, it will still last far longer than normal composted material. Since biochar stays in the soil longer it locks the carbon in for longer than if the tree dies and simply mulches into the soil. It also has many other benefits and to my mind one of the most useful is that it appears to provide an excellent environment for microzymas involved in the formation of humus. Some believe that humus can lock carbon in the soil far longer than even biochar.
Work is being done on mobile charcoal makers that can be used on the timber that is thinned from plantation as the make way for the stronger growth trees, not sure you would want to knock down a whole plantation just to put carbon in the ground
Posted: Fri Feb 13, 2009 12:25 pm
nik wrote:Pyrolisation is the burning without oxygen. The result of the process is a charcoal that is basically pure carbon with a whole lot of minerals still attached to it. This is usually ground up into small particles no bigger than wheat seeds (though size can vary).
Id offer a few points of clarification if I could
its very low oxygen rather than none at all
concerning terra preta
its a low temperature pyrolysis, the objective of which is not to remove all the tars, these are largely polycyclic aromatic hydrocarbons
, slash and burn is a higher temperature process, slash and char a lower one, which is what terra preta practices employed. These initial PAHs are theorized as important to mycelium and microbiological development in the soil.
another point would be that biomass with a larger lignin
ratio is favored.
normal charcoal is not bad either, but terra preta
is something a bit more sophisticated chemically and microbiologically
Terra preta's capacity to increase its own volume – thus to sequester more carbon – was 'discovered' by pedologist William I. Woods of the University of Kansas. This central mystery of Terra preta, is actively studied by many researchers from various disciplines.
Posted: Fri Feb 13, 2009 12:32 pm
slash and burn is a higher temperature process, slash and char a lower one, which is what terra preta practices employed
Does this comment suggest it is possible to slash and char in situ, rather than the kiln type set up in which I believe agri char is being reproduced.
Brings me back to my original question, asked in a different way.
Slash and burn we know is bad. Slash and mulch is the NSF recommendation. Slash and char????
Posted: Fri Feb 13, 2009 5:52 pm
its assumed that between 450 BC and AD 950 thats what they where doing
but its not just char, there are the remains of habitation, waste, animal processing, animal waste, pottery shards, then there is the whole microbiological and fungi aspect as well.
Slash & Char
what Id be working with, you'd be working with and they where working with are all slightly different. Charcoal has an amazing ability to retain and store nutrients and water, supporting a very rich microbial spectrum and stabilizing carbon within the soil for an exceptionally long time.
Consider char is part of most natural fire regimens, assuming fire is a regular phenomena and fuel loads dont accumulate, you would have a much lower temperature combustion with less ash. In a way human bio chars are just a mimicry, in slash and char its both char and mulch. The ecology in Australia is adapted to that. (Stephen Pyne
: Burning Bush. A Fire History of Australia (1991; paperback edition, University of Washington Press, 1998 The Still Burning Bush
Scribe Short Books, Melbourne 2006)
terra preta was a hybrid composting regimen that we still havent really recreated well. Experimentation with char, mulch and waste ratios and even mycelium and microbial inoculation experimentation is called for with different soils.
In permaculture its pointed out that if you spot a plant doing better in a location than your same plant, grab some soil and transfer it, you might be getting a more beneficial strain of fungi and organisms.
A friend of mine is an Environmental Researcher, specifically a BioGeoChemist
http://scholar.google.com/scholar?hl=en ... tnG=Search
just the plants your working with, much less the soils & biota make a pretty big difference (polyphenols = tannins
all in all some pretty complex interactions between differing chemical and mineral ratios plus the organic and life forms involved, sequestering char in soil is going to have a benefit, faithfully recreating terra preta though might be a bit of an exaggeration.
Posted: Mon Feb 16, 2009 9:00 pm
In the long run it is most definitely the soil biota that will make the difference in soil fertilty and plant growth. The thing with Terra Preta is that it did take a long time to make it.
I am very keen to see what difference will be made to the soil with the addition of biochar, composts, worm castings and bioactive soil additives of benefical micro organisms all topped of with stacks of mulch from slashed weeds.
Complex yet quite simple really
Posted: Tue Jun 16, 2009 5:20 am
I have found and use a product which is soluable humate, it is a processed form of Humus which I apply at 10kg/Ha mixed with my normal chemical fertiliser but at only 60% of normal rate.
Along with other microbe promoting techniques and inputs this is enableing me to acheive a 30% $$$ saving while giving me an increased yield result and reduced degradation of the soil organic carbon (SOC) content of my soil.
In fact it is expected that the SOC will be increased as a result and that year on year I hope to sustain 30% reduction of chemical fertiliser applications as my SOC improves each year untill I have a zero fertiliser application rate, possibly within 10 years.