[Terrapreta] Glomalin........ TP's Recalcitrant Fungal Secret

[Shengar at aol.com]

Hi all,
 
Here are a series of post that clarify the critcal roll of Glomalin for TP  
formation
 
 
Started by Philip Small at  
_http://forums.hypography.com/earth-science/3451-terra-preta-new-post.html_ 
(http://forums.hypography.com/earth-science/3451-terra-preta-new-post.html) 
( to catch all the hyper-links go to Hypography Forum)
 
Philip Small's Blog;  _http://transectpoints.blogspot.com/_ 
(http://transectpoints.blogspot.com/) 
 

Also, here is the Blog which I first read of Glomalin;  
_http://www.garyjones.org/mt/_ (http://www.garyjones.org/mt/) 

 
 


Glomalin and Terra Preta - 02-11-2007, 03:35 AM  

  
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Fellow blogger, Back40,  and I have been tossing out the potential glomalin 
link to TP function for  awhile. I even emailed Dr. Lehman enthusiastically 
about glomalin a few weeks  ago, thinking to pull my thoughts together on it for 
a blog post. He was not  unaware of the rationale. His entirely neutral 
response reined me in a bit.  

Since then my soil fungi:bacteria thinking has been highly stimulated by  
reading Jeff Lowenfels' "Teaming with Microbes" and it has hit me: it's got to  
be more complicated than just AMF kicking up their glomalin production. Maybe  
glomalin can account for the initial stages of transformation to TP, but there 
 are pitfalls to fungi as an explanation for TP's self-replication once it 
has  reached its full expression. By then the pH has come up, not so great for 
the  fungi. By then the phosphorus levels have come up, not so great for 
mycorhhyzal  mutualism. 

The soils I see in the pictures of TP remind me of the types  more conducive 
to high bacterial populations than fungal populations. If it is  fungi, it 
would seem to be from a highly adapted fungal species. Perhaps, but  could TP be 
an other-than-fungi/glomalin phenomenon? If so, we may be looking  for a new 
recalcitrant organic carbon based substance in TP and an undiscovered  pathway 
for its formation. 

I think TP formation is driven by plant root  exudates being delivered to 
grow microbial biomass, sequestering carbon pulled  from the air. The fungi-like 
bacteria, actinomycetes, seems a candidate. Next I  would consider the 
archeae. And because it is soil, the reality here has the  potential to be 
deliciously nonlinear, multi-staged, complex and  inter-connected.
 
 
 
Re: Glomalin and Terra Preta - Yesterday, 06:58 AM 

 
  
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Good post Philip, well  worth building on.


Quote:
Originally Posted by Philip Small  
(http://forums.hypography.com/earth-science/3451-terra-preta-post158692.html#post158692)  
I even emailed Dr. Lehman enthusiastically  about glomalin a few weeks ago, 
thinking to pull my thoughts together on  it for a blog post. He was not 
unaware of the rationale. His entirely  neutral response reined me in a bit.

I  expect he is on the case but unwilling to say anything until he is safely  
published. Glomalin drives a coach and horses through much previous TP 
research,  because its effects are so directly relevant that if not factored in, 
other  results are, well, flaky. Give the man time.


Quote:
it's  got to be more complicated than just AMF kicking up their glomalin  
production 
Certain to be true but is it  important? Review what we know:  
    1.  Charcoal massively increases AMF growth, and is used extensively for 
this  purpose in Japan. E.g. Saito & Marumoto (2002) 'Inoculation with  
arbuscular mycorrhizal fungi: the status quo in Japan and the future  prospects', 
Plant and Soil 244(1-2), pp. 273-279.  
    2.  AMF inherently produce copious amounts of glomalin (Driver et al 
(2005)  'Characterization of glomalin as a hyphal wall component of arbuscular  
mycorrhizal fungi', Soil Biology & Biochemistry 37(1), pp.  101-106). This 
glomalin is recalcitrant and persists long after the hyphae  have died.  
    3.  AMF are ubiquitous and are productive in tropical forest soil 
(Lovelock et  al (2004) 'Soil stocks of glomalin produced by arbuscular mycorrhizal 
fungi  across a tropical rain forest landscape', Journal of Ecology 92, pp.  
278-287).  
    4.  Fire does not reduce AMF the way it does other fungi, leaving them as 
the  dominant group for up to 15 years after a burn (Treseder et al (2004)  
'Relationships among fires, fungi, and soil dynamics in Alaskan Boreal  
Forests', Ecological Applications 14(6), pp. 1826-1838). Terra preta  soils were 
prabably continually burned during formation (Hecht in Amazonian  Dark Earths).  
    5.  Glomalin forms water-stable soil aggregates (Rillig et al (2002) 'The 
role  of arbuscular mycorrhizal fungi and glomalin in soil aggregation: 
comparing  effects of five plant species', Plant and Soil 238(2), pp. 325-333).  
    6.  Water-stable aggregates of a similar size to those characteristic of  
glomalin bind and protect soil components (Teixera & Martins in  Amazonian 
Dark Earths). This accounts for many of the properties of  Dark Earth soils: 
stability; water retention; carbon retention; nutrient  retention and reduced 
leaching; reduced CH4 and N2O emissions.
Perhaps  you have heard of Occam’s Razor, or of Einstein’s “smallest 
possible number of  hypotheses”? The important properties of terra preta do not need 
bacteria to  explain them. Bacteria work with AMF (Rillig et al (2006) 
'Phylogeny of  arbuscular mycorrhizal fungi predicts community composition of  
symbiosis-associated bacteria', Fems Microbiology Ecology 57(3), pp.  389-395), so 
as you say the reality will be found to be nonlinear, multi-staged,  complex 
and inter-connected, but they aren’t needed as independent agents.

Quote:
there  are pitfalls to fungi as an explanation for TP's self-replication once 
it  has reached its full expression. By then the pH has come up, not so great 
 for the fungi. By then the phosphorus levels have come up, not so great  for 
mycorhhyzal mutualism. 
Self-replication of  terra preta is reported by Amerindians but is there any 
scientific evidence for  it? It seems to be one of several questionable 
beliefs (German in Amazonian  Dark Earths), in this case perhaps based on Dark Earth’
s rapid recuperation  under fallowing. Another such belief is that TP does 
not lose fertility or break  down. It most definitely does if not maintained 
properly (German  again).

pH up? The mean pH of terra preta is 5.7, and of terra mulata 5.3  (Kämpf et 
al in Amazonian Dark Earths), higher than the awful common soil  but nowhere 
near suppressing fungi.

Phosphorus up? The high P (and Ca)  levels in terra preta are believed to be 
original, from the debris of  habitation, not accumulated. They are reported 
to be the main features  distinguishing terra preta from terra mulata, apart 
from the colour, which is  probably due to bacterial decomposition of the debris 
but has no known  beneficial effects. Terra mulata has low P and shows that P 
does not “come up”  in Dark Earths. A useful hypothesis: more glomalin will 
be found in TM than in  TP.

I had hoped that there was no link between TP and glomalin, because  then we’
d have two weapons against carbon dioxide instead of one. But the  scientific 
evidence is too compelling for me right now. Nevertheless, I cling to  the 
hope of a pleasant surprise when independent glomalin assays of Dark Earths  are 
published.




Re: Terra Preta Glomalin bacteria, nemata - Today, 09:18 AM  

  
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This may be of  interest
If glomalin stores 1/3 + of the world's carbon. .  .?!!!!!!

Glomalin on the Web
Glomalin hiding place for a third of the  world's stored soil carbon
Agricultural Research, Sept, 2002 by Don  Comis
A sticky protein seems to be the unsung hero of soil carbon  storage.Until 
its discovery in 1996 by ARS soil scientist Sara F. Wright, this  soil "super 
glue" was mistaken for an unidentifiable constituent of soil organic  matter.
Rather, it permeates organic matter, binding it to silt, sand, and  clay 
particles.
Not only does glomalin contain 30 to 40 percent carbon,  but it also forms 
clumps of soil granules called aggregates. These add structure  to soil and keep 
other stored soil carbon from escaping.
As a glycoprotein,  glomalin stores carbon in both its protein and 
carbohydrate (glucose or sugar)  subunits.
_Glomalin hiding place for a third of the  world's stored soil carbon 
Agricultural Research - Find  Articles_ 
(http://findarticles.com/p/articles/mi_m3741/is_9_50/ai_92589768) 

*******************************************

WASHINGTON  - A sticky protein shed by fungi living on plant roots is 
responsible for  absorbing and storing sizable amounts of the carbon dioxide 
pollution linked to  global warming, U.S. Agriculture Department scientists said. 

The  protein, glomalin, glues soil particles and organic matter together 
which  stabilizes soil and keeps carbon from escaping into the atmosphere.
_Planet Ark : Rich soil good for trapping  carbon dioxide -  study_ 
(http://www.planetark.org/dailynewsstory.cfm?newsid=17668&newsdate=09-Sep-2002) 

**************************************************  *
Charcoal in soil acts as a substrate for fungi which secrete a > glue,  
glomalin, that binds soil particles, water and nutrients together, so > the  soil 
work far better. The charcoal is not consumed, so this process is >  carbon 
negative, but Glomalin accounts for 27% of the carbon in soil, so >  adding 
carbon to soil as charcoal causes yet more carbon to be  sequestered.
_Dr. Evans Blog » 2006 » December »  07_ 
(http://www.atomicprecision.com/blog/2006/12/07/) 


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In 1996, Dr. Sarah Wright  and colleagues at the USDA's Agricultural Research 
Service isolated a  glycoprotein called glomalin that literally "gums up" the 
soil rhizosphere (the  interface between soil and plant roots) with carbon 
fixed from the atmosphere.  The compound is produced by common soil fungi called 
mycorrhizae that frequent  the roots of many crops. 
When Wright removed glomalin from soil samples, the  result was a lifeless 
mineral powder. The soil had lost its tilth - the  substance that conveys 
texture and health. She had inadvertently discovered the  fundamental factor of soil 
welfare, elusive for over 10,000 years. Humic acid,  previously thought to be 
the main contributor to soil carbon, could muster only  a tiny percentage of 
glomalin's carbon-storing capacity in the field.  
Another extraordinary finding was that elevated carbon dioxide levels  
encouraged mychorrizae to work overtime. Working with a consortium of scientists  
from UC-Davis and Stanford, Wright simulated CO2 projections for the year 2100  
and observed ramped up glomalin production, with thriving fungi. . . .
. Most  importantly, the USDA research demonstrated glomalin's tendency to 
buildup in  the soil. Intensively farmed fields consistently leveled off at 0.7 
mg of  glomalin per gram of soil, while undisturbed plots saw an increase from 
1.3 to  1.7 within three years. In hindsight, the Dust Bowl of the 1930's 
wasn't a  casualty of overfarming, but overplowing.
. .
I hadn't known, or had  forgotten, that mycorrhizae harbor and sustain soil 
microbes. It makes sense  given their habits of transporting phosphorous, 
nitrogen and carbon around  underground - the "dirt internet" so to speak. When 
mycorrhizae thrive, so does  eveything else.
_Muck and Mystery: Glomalin  Critics_ 
(http://www.garyjones.org/mt/archives/000401.html) 

******

Carbon Coalition Against Global  Warming
Work in the area of ammending soil with bio-char and, separately or  in 
combination with bio-char, promoting mycorrhyzal fungi to produce glomalin  seem 
both very promising in terms of the fundamental science. Both are fairly  recent 
discoveries with huge implications. Hopefully we have a few more rabbits  to 
pull out of the living soil hat.
_Carbon Coalition Against Global Warming:  February  2006_ 
(http://carboncoalitionoz.blogspot.com/2006_02_01_carboncoalitionoz_archive.html) 


**************************************************  *********
No one has mentioned worms?
I have seen one estimate of  phylum Nemata saying that if those in 1sq.m. of 
soil were stretched 'head to  toe' they would stretch to Mars.
Nematodes are the most numerous  multicellular animals on earth. 
The vast majority of species encountered are  poorly understood biologically. 
There are nearly 20,000 described species  classified in the phylum Nemata.
We know so little about soil fungi. We have  named about 10% of the life in 
the soil

The S.A.Indians say Terra preta  soil "grows".
I am inclined to believe them. They have been right about  everything else.
SEE 
_ET 9/98: First-ever estimate of total bacteria on  earth_ 
(http://www.sdearthtimes.com/et0998/et0998s8.html) 

Quote:
"Another  important part of the study was an estimate of carbon content in 
bacteria.  Carbon, of course, is a crucial element in numerous natural 
processes, so  knowing the amount of it could contribute substantially to knowledge of  
carbon cycles.
Scientists assume that carbon in the bacteria that live  in soil and 
subsurface takes up about one-half of their dry weight.
The  team thus found that the total amount of bacterial carbon in the soil 
and  subsurface to be yet another staggering number, 5 X 10**17 g or the weight  
of the United Kingdom.

Rather surprisingly, the group at Georgia  found that the total carbon of 
bacteria is nearly equal to the total  carbon found in plants.
The inclusion of this carbon in global models  will greatly increase 
estimates of the amount of carbon stored in living  organisms" 
My, My, How many more Rabbits ARE going  to come out of TP's hat?  

Erich J.  Knight 
Shenandoah Gardens
E-mail: shengar at aol.com
(540)  289-9750




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