Re: [compost_tea] Re: Re: RE: Aerators

From: <soilfoodweb_at_aol.com>
Date: Sat, 10 Apr 2004 23:54:01 -0400
I've been teaching a compost tea class the last two days, and so haven't been on-line much.  I am not sure I caught the beginning of this thread. 

But, I'll wade in with my usual, ah, aplomb..... GRIN!

Active bacteria (AB), total bacteria (TB), active fungi (AF) and Total fungi (TF) are measured by measuring length and width of these organisms in the soil, compost, water or tea you send in.  That gives you bio-volume.  We have measured the density of bacteria and fungi in soil for many years, and thus use the typical conversion for soil organisms to convert to biomass.

Comparing numbers of bacteria with numbers of fungi is nonsensical.  The largest organism on this planet is a fungus, and there are competitions going on for who actually has the largest individual fungus.  So, comparing bacteria, which are amoung the smallest organisms on the planet, with individual numbers of fungi is just silly.

Comparing biomass makes much more sense, because you take into account the mass of the organisms - you compare mass, not numbers of individuals. 

So, the values come as microgram per milliliter, if you are dealing with liquids, or micrograms per gram if you deal with solids. 

We also report HD, which is hyphal diameter.  The actual average width of the hyphae, which is an indicator of whether you have mostly "good guy" fungi, or typical fungi, or bad guy fungi.  A generalization, yes, but most people like to have some idea of good, bad, ok, and here's a general indication.  If the diameter in less than 2 micrometers, you have mostly not-so-good guys.  2 to 3 micrometers, the community of fungi is in the normal range - some good, some bad.  3 or above - life is good, pat yourself on the back, you have mostly the good guys. 

Protozoa are reported in numbers of individuals per gram or milliliter.  Three groups - flagellates (F), amoebae (A) and ciliates (C).  Flagellates and amoebae in soil are almost strictly aerobes, while ciliates prefer to consume anaerobic bacteria.  So, there's a hint, if you high numbers of ciliates, that you may have anaerobic conditions present.

N is for nematodes, also reported in total number of nematodes per gram, or mL.  We also identify to genus or species, and that is reported, although in this case, there were no nematodes, so no species ID.

Tea
65AB  11,008TB  19.7AF  102TF  3.5HD  17F  14A  1C  0N
>
AH
AB191  TB421  AF34.4  TF1228  HD2.5

We always report the "desired range" on hte SFI report, based on years and years of collecting data from thousands of samples.  Based on that knowledge, we came up with the desired range. 

Labs that don't have that background use the numbers that SFI developed.  They have not done the tough work, doing the assessments for years and years.  They cannot justify the meaning of the numbers they put on their reports.  They have no quality control of what they do. 


--------
Samples were sent to several of the other labs.  We used a gradient of samples from ag soils hammered with pesticides, to old growth forest samples.  Clearly the nuked ag soils are the poorest soils, and the old growth forest soils are highest. 

Want to guess what the other labs reported?  Did they get the gradient right?  I'll be putting the data out in the next e-zine.......

Elaine Ingham
President, Soil Foodweb Inc.
SFI Corvallis, OR
SFI Port Jefferson, NY
SFI Lismore, NSW, Australia
SFI Hilversum, The Netherlands
SFI Cambridge, New Zealand
SFI Culiacan, Mexico
SFI Jerome, Idaho
http://www.soilfoodweb.com

Yahoo! Groups Sponsor
ADVERTISEMENT
click here


Yahoo! Groups Links

Received on Sun Apr 11 2004 - 23:15:10 EDT

This archive was generated by hypermail 2.3.0 : Tue Feb 07 2012 - 14:15:11 EST