Healthy soil and sustainable growing

["TradingPostPaul" <tradingpost@riseup.net>]

from Humus - Understanding the Soil Processes
http://www.petrik.com/PUBLIC/library/ups.html#humus


The production of humus is a complex process. In general cyclic substances
like
phenol groups and also other like organic acids and vitamins (humus is also
related to crude oil) are polymerized with help of enzymes,like phenol
oxidase.
These cyclic compounds are both from plant parts(like lignin) and are also
produced by the microorganisms. Mostly fungi, actinomycetes (Streptomycets)
seem
to be responsible for humus formation. Aspergillus, Pisolithus,
Rhizoctonia,
Streptomycets are only but a few examples of microorganisms actually
capable of
synthesizing cyclic(aromatic) compounds and form them into humus from
non-cyclic
materials.
-----------

from Humus: Still a Mystery
http://www.nofa.org/tnf/humus.php

Humus is essentially a massive storage battery containing energy that was 
originally derived from the sun. Researchers in England discovered that an
acre 
(furrow slice) of soil with 4 percent organic matter contains as much
energy as 
20-25 tons of anthracite coal. Another researcher in Maine equated the
energy in
 that amount of organic matter to 4000 gallons of #2 fuel oil. This organic

energy, which is stored as carbon compounds, was originally derived from
the sun
 by autotrophic organisms such as plants that can extract carbon from 
atmospheric carbon dioxide. About one percent of the energy from the sun
that 
reaches plant leaves is used to photosynthesize carbon compounds. During
the 
plants' life much of the energy that is absorbed from the sun is utilized
for 
growth, foliage production, flowering, seed production and other functions.

About 10 percent of the absorbed energy, initially from the sun, is left 
available to a consumer, e.g. an animal that eats and digests the plant.
Like 
the plant, the animal uses most of the energy it consumes for functions
such as 
growth and sustenance but can offer about 10 percent of the energy it
derived 
from plants to the next consumer in the food chain.

Humus in the soil has more real value than money, real estate, stocks or
bonds. 
Its value doesn't fluctuate; it doesn't become scarce in a recession; it's
worth
 can't be depleted by inflation and it can't be stolen. It is the direct or

indirect source of sustenance for all life on earth. It can sometimes be
lost by
 environmental changes but more often, its demise is from either the apathy
or 
the inadvertent errors of the steward who tends it.

Humus is a renewable resource. Its presence in the soil can be maintained 
indefinitely. Unfortunately, many agricultural and horticultural practices
are 
essentially mining humus. Like other mined products, such as coal, minerals
and 
oil, the natural resource can eventually be exhausted.

The popular scientific definition of humus is "A more or less biologically 
stable, dark, amorphous material formed by the microbial decomposition of
plant 
and animal residues". It is difficult to visibly differentiate humus from 
organic matter in other stages of decay. Compost, well rotted manures and
peat 
are not necessarily humus. However, at some hard-to-define point, all of
these 
organic materials will contribute immeasurably to the humus content in the
soil.

It is not realistic to think that one can quantify or qualify humus
production 
from contributions of organic matter to soil. There are too many factors
that 
control its formation and existence in the soil environment. One can only
assume
 that cultural practices that both minimize the depletion and contribute to
the 
formation of humus will maintain the best possible level of soil humus for
each 
individual environment.
----------------

paul, tradingpost@riseup.net
---------------
The outstanding scientific discovery of the twentieth century is not
television, or radio, but rather the complexity of the land organism. Only
those who know the most about it can appreciate how little we know about
it. 
   - Aldo Leopold in  Round River, 1933