It has been a fair while since I
posted anything on biochar. This article
will allow readers to refresh themselves on the basic details. As usual the science is poorly expained and
adsorption is never understood.
Yet we get something of great
value in the comment were we receive a first hand report on the application of
biochar as a one percent component of the feed.
This has comparables in the
application of zeolites to pig feed in Cuba in the eighties. It worked then for the same reasons.
The take home is that all
livestock operators need to adopt an in-house bio char kiln to convert surplus
plant waste into biochar. This can be
used to supplement the feed and produce a superior manure product. We already know that this is excellent
practice for chickens and pigs, while cattle references need to be seen yet.
It certainly justifies the small
batch production of biochar whil providing an interim step for introducing the
biochar back to the soils.
What's the big deal with biochar?
Heating up crop production with this ancient soil amendment.
By Dr. Robert M. East, Ph.D.
The term 'biochar' refers to black carbon formed by heating biomass
(plant wastes, feedstocks, etc.) in an oxygen-free or low oxygen environment so
it does not combust. The technical term for this process is pyrolysis.
Traditional charcoal is one example of biochar produced from wood. However, the
term 'biochar' is much broader than this, encompassing black carbon produced
from any biomass feedstock.
Biochar is high in organic carbon, largely resistant to decomposition,
and is intended to be used as a soil amendment. A widely-held view is that the
best biochar is formed by relatively low temperature pyrolysis, ideally at
about 500 degrees Celsius. This is a high enough temperature to achieve maximum
surface area but also low enough temperature to retain some biological oils that
would normally burn off. Commercial charcoal, which is manufactured at higher
pyrolysis temperatures and intended solely as an energy source, typically
contains chemical additives rendering it unsuitable as a soil amendment.
Many soils contain some naturally occurring charcoal which was produced
from natural/prescribed fires. Where human population sizes allow, smallholder
farmers in developing countries practice “slash and burn” cultivation which
relies on the production of charcoal and its ultimate incorporation back into
the soil for fertility. For thousands of years charcoal has been used by
traditional cultures as a soil amendment and there is evidence that it
positively benefits crop yields. The most well-know example is the fertile
Terra Preta soils
in Brazil .
Crop yields on these soils have been shown to be much greater than on nearby
soils which were not enriched with charcoal; this despite the soils having
recently evolved in a similar environment. Japan also has a long tradition of
using charcoal in soil, a tradition that is being revived and has been exported
via agricultural technical assistance over the past 20 years to countries such
as Costa Rica .
For farmers and gardeners within the Northern Hemisphere, biochar
produced from woody plant slash and animal manure can provide a sustainable
source of soil amendments which help close the loop in the carbon cycle.
However, biochar materials can vary widely in their characteristics and so can
soils. Biochar has potential to offset humanity’s contribution to carbon
dioxide emissions by sequestering the embodied carbon as well as altering
nitrogen transformation rates within the soil. Examples of nitrogen fluxes and
transformations affected by biochar addition include inorganic-nitrogen
leaching, ammonia volatilization, nitrogen fixation, and N2O emissions.
Biochar improves soil by three critical services: First, it acts like a
sponge to soak up water, hold and slowly release it to soil. This can be an
important characteristic in drought prone areas and/or on soils low in organic
matter. Second, biochar acts as a storehouse adsorbing nutrient ions for
exchange to soil biology. Third, biochar is a substrate which provides habitat
and refuge for soil microbes. As a soil amendment, biochar creates a more
stable soil carbon pool that serves as a net withdrawal of atmospheric carbon
dioxide. The enhanced nutrient-retention capacity of biochar-amended soil not
only reduces the total fertilizer requirements but also the climate and
environmental impact of croplands.
Biochar-amended soils have shown ranges of 50-80 percent reductions in
nitrous oxide emissions, reduced runoff of phosphorus into surface waters, and
reduced leaching of nitrogen into groundwater. As a soil amendment, biochar can
significantly increase the efficiency of and reduce the need for traditional
chemical fertilizers, while potentially enhancing crop yields. Furthermore,
renewable oils and gases co-produced in the pyrolysis process can be used as
fuel or fuel feedstocks, thus helping close that loop.
Data on the effect of biochar on crop yields is still rudimentary –
only a limited number of crops grown on a limited number of soils have been
investigated. The interactions between crop, soil type, local conditions, and
biochar feedstock, production method and application rate should be studied in
far more detail before large scale deployment of biochar as a soil amendment is
contemplated. Nonetheless, there is evidence that at least for some crop/soil
combinations, addition of charcoal may be beneficial.
Field trials using biochar have been conducted in the tropics over the
past several years. All showed neutral or positive results on yields when
biochar was applied to field soils and nutrients were managed appropriately.
Large scale field trials have recently begun on highly fertile Iowa soils by the US
Department of Agriculture’s Agricultural Research Service. First year results
are positive, yet it will take several years before definitive results are
available.
Existing evidence suggests that raising soil pH may be biochar's most
important documented contribution to influencing soil quality. Soil pH mostly
influences the relative availability of nutrients. At low pH, aluminum
toxicity is particularly harmful to plant growth. Aluminum toxicity is an
extensive and severe soil problem, and biochar can be an easily available
solution to combat it. Soil phosphorus availability is highly dependent on soil
pH range, and thus biochar can be used to substantially increase phosphorus
availability in soils that are below the ideal pH range (6.5 to 7.0). Used
alone, or in combinations, compost, manure, and/or synthetic fertilizers are
added to soils at certain rates every year.
Application rates of these inputs may potentially be reduced when
biochar is used as a soil amendment.
Currently, many biochar producers are seeking to become USDA “Bio Preferred”. While this is not the same as certified organic, it does ensure that the product is bio-based and not synthetic. Such certification also facilitates easier business transactions with state and federal procurement agents. The ultimate goal to make biochar compatible with organic farming will be achieved by instituting a set of quality control and environmental standards that are acceptable to the Organic Materials Research Institute. It has been suggested that criteria related to the feedstock used, the method of pyrolysis, the properties of the biochar, and the application of biochar should be met for the use of biochar in organic farming.
Dr. Robert M. East, Ph.D. is Associate Professor and Director of
the Environmental Studies Program at Washington & Jefferson College,
Washington, PA. Beginning in June, 2011 and continuing for the next five
years, Dr. East is leading a collaborative research effort between
Washington & Jefferson College and the Rodale Institute to quantify the
effects of biochar on soil biology/fertility and crop yields on the Rodale
Institute’s Kutztown farm. The first crop harvest is expected to occur in
October and we’ll be reporting our initial observations this fall/winter
here at www.rodaleinstitute.org. Sign up for the
monthly e-newsletter to be kept abreast of project
developments and updates.
Submitted by JP Daugherty (not verified) on Wed, 09/07/2011 - 16:10.
I thought you'd be interested in knowing that I have been feeding my
chickens charcoal I produced from an outdoor wood burning stove (100 percent
natural, no additives that are not natural in even starting the fire) which
heats this house in the winter here in NE Missouri .
I was browsing for biochar amendments to chicken litter in composting
when I came across a very interesting article on how a particular scientist
found that adding the chicken manure to biochar significantly decreased the
amount of ammonia nitrate out gassing by converting the ammonia into the more
stable ammonium. He wondered if he could do it inside the chicken rather than
mix afterwards so he started supplementing his chicken food with around 1-3
percent ground to kitty litter sized particles of biochar. Within the chickens
the biochar is automatically binding the ammonia into the ammonium form before
excreted resulting in very little nutrient out gassing loss.
No ammonia smell or any other smell for that matter!!!
I can testify to this since I have been feeding my chickens around 1-3
percent ground charcoal for over six months. Their manure does not smell. Nor
is it runny or even gross. It comes fresh out of the chicken full of plant
material with a dark green to green black coloration. Even when picking it up
and examining it, it broke apart like a well aged horse manure/fibrous texture
and was wet but not even close to being runny. Like the proper moisture level
you'd want for growing your own mushrooms. (Will test that later in vermiculite
and rice flower cakes and shitake)
With the manure you could tear it apart in your hands and feel it was
properly moist but after dropping it to the ground to go and wash hands there
is no residue nor moisture that gets on them. They remain clean with no smell.
Naturally I wash my hands anyways because it was still poop lol.
The chicken coop never smells. Accidental contact made with their waste
is not gross or messy like before. Easy to scoop and add to the compost pile.
Their bedding which is straw and hay is primarily what is composted with random
rotten vegetable or over ripe material from the garden results in a constant PH
of 6.0-7.0, is much easier to turn, and gets better air and water distribution
throughout requiring minimal effort to wet, and seems to be breaking down
non-shredded material in 2-3 times the rate of time as it would take before
when non-shredded material was added with gypsum and every layer had to be wet.
Other things I have seen is that I do not have to add any charcoal to
the compost pile. As a matter of fact, my free range chickens around the house
are biochar distribution workers that are helping to rebuild the lawn and
garden and they do not even know it. lol I only get to gather their roost
droppings from the evenings. When you accidentally step on a pile of chicken
poop out in the yard it doesn't stick to your shoe and just mashes flat and
disappears relatively easy with a light rain. So I am never tracking chicken
crap into the house on accident.
Another thing of note is that I can now use fresh chicken manure in
rather sizable quantities earlier than before the use of biochar. Normally I
would have to let it age (In other words out gas and leach) down to the point
of being barely a fraction of the size of what it originally started at. With
biochar you end your composting with what seems like a larger pile. The char
that came within the manure is absorbing most of the ammonium nitrate and
doesn't seem to be reaching its entire absorbing capacity which means I might
have to cut back just a tad bit by staying at 1 percent biochar used as feed
for the chickens. When testing the final product (At least to me it looks like
black rich dirt)for nutrient NPK values I landed at indications saying I would
need to use 12/12/12 (Not a large amount surprisingly) to bring it up to its
max for this area.
The compost pile retains water for long periods of time. The initial
watering took less time than when biochar was on incorporated into the chickens
diet. We have been in a drought here for around two months. The pile is open
and exposed to the sun. When we were near flooding at the beginning of the
summer, I noticed no water pouring out of the downhill side of the pile telling
me that its water holding capacity is fairly high. When I attempted making
compost tea after reaching the holding capacity of the allotted sample of five
gallons of the soil/compost very little brown to black colored water would
leach out telling me that it is doing well to trap the organic available phosphate
and Nitrogen but I did not test the water sample so that is just speculation.
Freshly composted to dirt with high organic small particulates that
only required less that what seemed 4 months worth of decay with minimal
wetting or turning. This was applied directly to out door plants which were
failing late in the summer due to drought. Removed them from the ground and
placed them in pots with my new dirt. Energy hungry plants like columbine took
off from 3 leafs to more than I can count in less than a month. It has not
burnt anything else I have tested it on. Not a completely controlled and
documented process as you might tell by my description . Next year will be.
Here is the website where I stumbled upon this idea.
Also of note before I go, when dressing chickens and examining their
gizzard and craw contents, I would see black pieces of charcoal that were used
for grinding the food. In the gizzard they were ground smooth to being almost
oval with rounded ends and shiny like a river stone. So the biochar is being
introduced before the main intestinal digestion. Like they are chewing their
food with charcoal teeth if you will. So nutrient absorption starts
immediately. I no longer feed my chickens oyster shell since they are smart to
pick up small limestone rocks of their own around the driveway round about. So
they are still getting their calcium. They are not just entirely using charcoal
to grind up their food but if I had to venture a guess just through visual observation
of the gizzard contents 50 or more percent of the inorganic substance within
that organ was charcoal. Maybe accounting for near 10 percent overall stomach
content but without proper measure, those numbers may not be near exact.
Nice content and useful too, i also have these feed supplement
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