RECOVERING DEGRADED SOILS
MILTON MACIEL
(In celebration of
International Day of Soil Conservation – December 5th )
Organic Agriculture
may be as productive as conventional chemical agriculture, once the appropriate
level of technology is applied. However, it won't squander that LOT of energy that is lost everyday by the absurd
mega-agribusiness systems.
With a reduced
fraction of that energy we can recover and reconvert most highly degraded soils
that chemical agriculture has transformed lush forests and prairies in. Recovering
degraded soils, eroded soils and even land from mining and road earthworks is
not so difficult and do not demand such a long time - neither so much energy -
as is most believed.
This is not a heavy mechanical work,
performed by oil guzzling machines, neither is something that consumes large
amounts of compost - again with expensive production, transport and application
(more oil and energy). Of course, in cases where compost is available nearby at
real low cost, it may be used in a bio-remediation process. But things are much
easier, faster and less costly. NO compost or manures needed.
A considerable part of my personal work has involved my consultant job of converting conventional areas into organic ones,
for my clients. Then, for decades, I've been used to receive the most degraded
or eroded parts of a farm so the owner could test our organic methods of
conversion. We ask then a period of only two years to convert those bad plots
into certifiable organic soils. Sometimes, because of bad chemical
contamination, we have to wait for an additional year, only because that is the
rule the Certification organization must obey.
What is the magic, or the secret? None!
It is just a matter of using BIOLOGY, not
mechanical or chemical processes. Just give soil - or subsoil - a chance. Lend
then a helping hand, represented by a small army of microorganisms and seeds
and a small amount of leguminous seedlings. A little rock phosphate and a very
small fraction of gypsum - for the seedlings. If available, apply a dose of
rock dust to the land (You don't have to lime now). Do it in the rainy season
and watch Mother Nature doing her job, her very fast and complete job.
What you do is to supply the surface with a
generous but very cheap 'cocktail', a mix of twenty or more kinds of graminiae and leguminous seeds.
Leguminous HAVE TO BE inoculated with appropriate Rhizobium breeds and both
leguminous and grasses seeds HAVE TO BE inoculated with mycorryzal fungi. At
the same moment we involve the seeds with a "glue" of clay and
microelements. That is a very cheap and rapid process.
Well, seeds will fall in degraded or even
barren land. But some kinds of seeds in the cocktail will survive and germinate
at the expenses of its own reserves, and, in the cases we choose to use it, of
the tiny 'peel' surrounding them. This will happen notwithstanding pH values of
4 or less and severe compacted surface. Rhizobium will get Nitrogen and will
stimulate mycorryzal fungi to form more mycorryza. This will help to feed
Rhizobia themselves. And this association, this perfect symbiosis of bacteria,
fungi and plant roots will get N2, phosphorus, potassium and all needed
minerals. Very deep leguminous roots will bring nutrients from lowers layers of
subsoil.
LIFE will start to thrive and, by
consequence, an organic layer of decaying matter will start to cover the
surface soil. Then the most important part of the process will happen. Those
wonderful, formidable, incredible, blessed creatures erroneously misnamed WEEDS
will come SPONTANEOUSLY. It is now the second round: they'll thrive, compete
and kill many of their leguminous and graminiae 'parents' and BIOMASS will
become more and more abundant.
But that is still only a part of the whole
process. Now is the time to consider our leguminous seedlings, the arboric (trees) leguminous that are
coming to the front.
Conventional modern agriculture destroys
soils with unprecedented velocity, losing former fertile surfaces to erosion,
salinization, acidification - leading, in many cases, to final desertification.
Bad ancient processes, as overgrazing, can also cause much harm.
In spite of the fact that nature may take 500
years to form one only inch of fertile topsoil, we don't have to wait for very
long times to recover degraded soils. If we help nature with the right
BIOLOGICAL tools, it will do the same in a very short time interval.
The first part of the recovering process
involves the use of inoculated seeds of graminiae and leguminous plants.
Inoculums are the correct strains of Rhizobium bacteria and mycorryzal fungi.
Seeds may be, optionally, coated with a tiny 'peel' of clay with
micronutrients. The whole process of inoculation and coating is a very
inexpensive one.
Key to this process is the SIMULTANEOUS use
of nitrogen-fixing bacteria associated with mycorryzal fungi. These and the
corresponding mycorryza stimulates the growth of nitrogenase activity of the N2
fixing Rhizobium bacteria. In symbiosis with the plant roots, this promotes a
better mycorryza development. Then, at the mycorryzosphere, other
microorganisms are able to produce the breakdown of primary minerals, releasing
other mineral nutrients to plant roots. Nitrogen is made available by Rhizobia
and Phosphorus by mycorryza. In severely unbalanced surfaces, as those
resulting from mining earthworks (bauxite, for example), some charcoal dust and
rock dust may be needed, but that is exception, not rule. Rock dust is so
inexpensive that it should be added ALWAYS to any soil, degraded or not, once
at each 6 or more years.
What is important is to employ a microclimate
compatible mix of leguminous and grasses seeds. A mix of circa 20 different
kind of them must be thoroughly mixed, inoculated and coated in the same operation.
For some of the leguminous seeds, dormancy has to be previously broken, mostly
with boiling water. So the heart of the process is not in the field, but in a
small NURSERY, where you must select, mix, inoculate and coat your seeds. And
where you may produce your leguminous seedlings, also inoculated with Rhizobium
and mycorryza.
In very coarse and barren places, you don't
have to level nor lime horizon A. Let this to the more advanced phase of
seeding or transplanting the commercial plants. Now all you have to do is throw
your seed cocktail over the ground and - if possible - to compact them softly
against the surface. In most cases this is not needed and it is more convenient
to supply the seeds with a somewhat more thick layer of clay/micronutrients
coating. In extreme cases, we may resort to Masanobu Fukuoka's 'seedballs', as
used to start the process of restoration of the heavily eroded mountain slopes
of the 'Serra do Mar' in Cubatao, Sao Paulo, where the seedballs were applied
by airplane.
As I have already mentioned, several species
of the seeds will germinate and survive, once you have sown them in the rainy
season, of course. Other species will die sooner or later. That's why we have
to employ a large variety of leguminous and graminiae seeds. The ones that are
more apt will
survive and colonize
the field, bringing conditions to produce an organic layer over and inside the
soil, where other forms of life will develop and grow.
The most important forms are WEEDS. They will
come spontaneously and they will compete with the 'parent' plants, killing many
of them. Once again the fittest survive and Darwin smiles. The final result is that
nature itself is now creating a consistent biomass and is getting and recycling
nutrients from subsoil and from air.
But, with somewhat more investment - never
comparable with the conventional agriculture wasting of energy - we can enhance
the whole process even more. We work now with arboreal leguminous SEEDLINGS. We
use our nursery to produce those seedlings, in small bags, with a substrate of
clay, sand and - if
available and cheap, 1/2 pound of chicken manure. If not, just put some gypsum
to supply a minimum of sulfur and incorporate 1:1000 diluted EM-4 (Efficient
Microorganisms). Of course, as the investment is not very large, the best you
compose your substrate, the most
healthy and vigorous
will be your seedlings.
At their 4th to 6th month of life, seedlings
are transplanted in the field under restoration. A small tractor, biodiesel
fuelled, will drill holes in programmed
spacing and will transport the transplanting crew with the seedlings. Do not lime or fertilize the plot. The
only thing added is a small amount of a mix of rock phosphate and rock dust,
placed in the transplanting hole. Just do that in a rainy season and forget all
about it. You don't have to do anything else. Let the seedlings fight for
survival - with previously sown plants and with the invading weeds. Don't
forget, this is Nature, this is natural competition, and we'll see once again
the survival of the fittest.
You won't believe in your eyes. In a few
months all that once degraded surface will be covered by tenths of different
kinds of living plants. Grasses, leguminous bushes, leguminous trees starting
to grow, and blessed, blessed weeds. At 20 months after transplant, you'll see
some species as Albizia guachapele
almost 4 meters high. Under the canopy of lush trees, bushes, grasses and
weeds, life is back again to former wasteland.
Now you may prepare yourself to intervene in
this revived land for the sake of your commercial plants. But do it correctly
now. Incorporate the maximum biomass you can, cause the minimum soil
disturbance, keep microorganisms as your most important registered workers. And
do not forget to pay their salaries (by learning their biology), as they
deserve it so much. Don't be ungrateful, don't treat them as illegals.
Let’s summarize the
play by naming and rewarding the main actors and actresses (not all of them, a
too long list):
Seeds:
Brachiaria
brizantha cv. marandu, Albizia guachapele, Digitaria
swazilandensis,
Canavalia ensiformis, Mucuna deeringiana, Crotalaria juncea, Cajanus cajan,
Stilozobium aterrimum, Leucaena leucocephala, Gliricidia sepium, Acacia mangium, Erythrina verna,
Goldmania paraguensis, Mimosa
caesalapinefolia,
Senna siamea, Andropogon gayanus, Setaria sphacelata cv. Kazungula
The main cast - microorganisms (“And the
Oscar goes to...”):
N2 fixing: Rhizobium spp and a dozen others specific Rhizobia
inoculum.
Mycorryzal fungii: Glomus clarum -
Gigaspora margarita
Best Supporting Actors:
Trichoderma
spp ; EM4 (these are 71 different
guys dividing one only statuette)
The Theater: Your small but very efficient
NURSERY.
Restoring degraded
land is not difficult nor expensive. This is not theory, nor new technology,
I've been making a live doing that for decades. Degraded pasture and degraded
horticultural land have been a blessing for me since 1983, when for the first
time I purchased a plot of very degraded horticultural land in Ibiuna, some 25
miles from Sao Paulo
city. The owner of that farm was forced to sell me a part of it or he would go
completely bankrupt. He had been cultivating that area with
potato monoculture for
some years, following all the rituals of the horrible poisoning technique for
chemical potatoes.
After some years he had degraded his soil
so much that he was expending an astounding amount of pesticides and
fertilizers with increasingly negative results. Then, at the first spike of low
prices at harvest time, he was broken. He had to sell part of his land, lost
his machines to the bank and all he could save was an used medium size truck.
No news, a very, very common sad story in rural areas. This one is just a bit
more sad.
As I started to prepare my new plot, I
hired him and his two adult sons as my part-time labor force. Their first task
was to dig two deep (12 feet) trenches. I jumped inside with them and they were
exposed, for the first time in their life, to the “dantesc” view of a too thin
and sterile topsoil (horizon A) and a compact slab of subsoil, so hard they
couldn't make a scratch on it with their nails.
Now they could see, with their own eyes,
the inglorious fight of the poor roots against that slab. Now they could
understand why they had to irrigate everyday, sometimes twice a day, and why
their tubercles became smaller and smaller harvest after harvest, despite the
increasing dose of fertilizers and pesticides they had to employ, cycle after
cycle of production. The land was exhausted and only very competitive kinds of
weeds could thrive, making good use of their fertilizers and forcing them to
expend more and more on weeding. Pure Dante's Hell...
Oh, my poor neighbour, so kind, so helpful,
such a dedicated worker, such a loyal friend, so deceived and so... poisoned!
He has been deceived by the Mortal Machine, as I call the System - all that
misguiding ensemble of techniques and useless and poisoning products he was induced
to buy and apply for so many years, at the expenses of his money, his health
and, at last, of his own life.
Yes, when we met and started to work
together, he was already a count more in the extended role of victims of
pesticides, very ill-health. He was only 54 but his look was that of an old
man, a very thin old man. The most amazing and saddest part of the story is
that he wasn't aware that his health problems came from the toxic residues of
pesticides. He didn't believe me and it has been very difficult to take him
with me to Sao Paulo ,
to a clinic with physicians specialized in agro-toxics
(Agrotoxics is the
name we prefer to use for pesticides, in Brazil . It is much more real - and
fair).
With the best possible treatment my neighbor
recovered from the acute and part of chronic effects of agrotoxics he had been
exposed to, for so long time . However, the deadly toll of Mortal Machine was
already been demanded from him. He died from a lingering cancer one month
before his 57th birthday.
His wife, his two adult sons, his 12 years
boy, his only daughter-in-law - all of them were submitted to analytical and
medical tests and - bingo! - they scored, together, 16 different agro toxics in
their
bodies, at high risk
levels. Needless to say, they converted to Organic, of course.
That is one of the reasons why I call, in
my books, articles and lectures, the System a Mortal Machine. Indeed it is a
Murderous Machine. Anyway, it is MM.
But there are many other reasons to name
the System a Mortal Machine. See: WHO killed that soil we examined inside the
trenches? Who killed the patrimony of that man? Who killed his hope of a better
life? The same Machine that killed the man himself. Furthermore, who forced
that kind, gentle, religious man to spread the seeds of death himself - by
selling tons and tons of poisoned potatoes every year.
No, my poor friend
wasn't prepared to understand that the malpractices of the techniques and
products he was induced to employ leaved too high residuals of toxic active and
'inert' ingredients in the potatoes he spread, through wholesales market ways,
to dozens and dozens of cities. Yes, MM
kills at distance,
both in space and time.
MM killed my neighbor and surely helped him
to kill some other of his fellow creatures that he, as a very religious man,
tried so hard to learn how to love. MM gave my poor innocent friend a proxy to
kill in her behalf. It's both ironic and tragic, that even many, many years
after his death, my neighbor is still helping some people to die. Perhaps, for
instance, that young lady with a breast cancer, whose loving mother just loved
to eat my friend's potatoes when pregnant.
Well, fellows, I'm sorry if my words seem
to be out of context in a text whose subject is degraded soils. But it is not!
Our biggest problem is not to restore soils. It is to STOP MM people and
corporations from degrading soils. Or, literally, to stop MM from
killing soils, after it has already murdered forests and prairies and savannahs,
and caused the extinction of thousands of vegetal and animal species.
MM is terribly powerful, we are no
opponent for it. But it has a much more powerful enemy, already visible at
horizon. Its name? Simple: PEAK OIL!
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