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[Livingontheland] The Soil Food Web: The Dirtiest Scandal of All
- From: "Tradingpost" <tradingpost@lobo.net>
- To: livingontheland@lists.ibiblio.org
- Subject: [Livingontheland] The Soil Food Web: The Dirtiest Scandal of All
- Date: Fri, 25 Jul 2008 21:16:20 -0600
The Soil Food Web: The Dirtiest Scandal of All
http://www.organicconsumers.org/articles/article_13730.cfm
* Daily Kos, April 5, 2008
Straight to the Source
I just read a book that turned my understanding of the world on its head. I
thought I was a good tree-hugger before. I thought I was an effective
proponent of organics too. The truth is, I had NO idea what I was talking
about in any sort of concrete way beyond a general idea that it's bad to dump
poison on the earth and kill living things.
Then bara told me to read a book called Teaming with Microbes: A Gardener's
Guide to the Soil Food Web. For a solid week, I had my nose buried in this
book and all I could talk about to anyone were bacteria, fungi, and
nematodes. The contents of that book expose the DIRTIEST, FILTHIEST scandal
of all in our society.
Why dirtiest? Well, for one thing, it's all about dirt. Or - to use a better
word - soil. But bad puns aside, we would have a VERY different and MUCH
healthier environment if the knowledge in this one little book were widely
known. You'd see no dead zone the size of New Jersey in the Gulf of Mexico,
for example, and that's just the start...
Senators and Congressmen, if you're lurking, please read this. James Inhofe,
I mean you too!
Let me give you a quick synopsis of what this book says that is so amazing
and then translate it for you in terms of what it means for our environment
and society as a whole (since it affects a whole lot more than just the
environment in terms of the major categorizations of issues we all care
about).
What Is Meant by Soil Food Web?
We say "soil food web" instead of "soil food chain" because it's not as
simple as one species eats the next who in turn gets eaten by the next and so
on. Typically, bacteria and fungi are the bottom of the food web and they are
eaten by protozoa and nematodes. Everything else kind of falls in line after
that - earthworms, bugs (which can be categorized as "arthropods" in order to
include spiders and such), and whatever else.
How Plans Control These Microorganisms
OK, here is the REALLY cool part. Plants (which we typically don't think of
as that active... you know, person in a coma = vegetable) totally control
what goes on underground. They act like choreographers, controlling the
microorganisms around them in order to get the nutrients they need and get
protection from pests and diseases.
Plants secrete something called "exudates" (think of it like sweat) from
their roots and leaves. The area around the roots, by the way, is called the
rhizosphere. The bacteria and fungi flock to the rhizosphere and coat the
roots in order to consume the plants' exudates. These bacteria and fungi
contain within their bodies the nutrients (particularly nitrogen but also
calcium, magnesium, phosphorus, and other nutrients too) the plants need to
survive.
These little critters are all crowded in tightly around the roots in the
rhizosphere, and bacteria tend to create a layer of slime around themselves
too, making it altogether much more difficult for pest species to attack the
plants.
Also hanging out in the rhizosphere are protozoa and nematodes that prey on
the bacteria and fungi. They eat the bacteria and fungi and then poop out the
nutrients the plants need, right smack next to the plant's roots where the
plant can use them. Isn't that brilliant???
Even more brilliant is the way plants use fungi to get nutrients from far
away. Plants obviously cannot move but fungi can extend very far in threads
called hyphae. These hyphae extend far through the soil, finding nutrients
like phosphorus and carrying them back to the rhizosphere to make them
available to the plants.
Think about it - when you dump nutrients on plants directly (as fertilizer),
some of those nutrients hit the plants' roots and the rest just leaches down
through the soil into the groundwater or wherever. The fertilizer's high salt
content kills the microorganisms in the soil food web too. You've got nothing
left in the soil to feed the plant, so soon enough you need to add more
fertilizer.
On the other hand, if you let nature take its course, the
plant-choreographers will keep all of the nutrients they need right beside
them in the rhizosphere in the bodies of bacteria and fungi, ready to feed
them as the bacteria and fungi are eaten and excreted.
Sounds to me like the natural version would be our equivalent of having a
cell phone and a web directory of delivery meal services whereas the
so-called modern version would be like living in a refugee camp and relying
on occasional shipments of aid to eat anything.
Another amazing adaption by plants? Plants differ in how they like to receive
their nitrogen. Typically plants like grass and veggies prefer to get one
form of nitrogen that is produced by bacteria in soil with a pH higher than 7
(and bacteria put out slime with a pH of 7, raising the overall pH of the
soil). Trees typically prefer their nitrogen in a form produced by fungi that
live in soil with a pH lower than 7.
Want to know what trees do to promote fungal growth around their root
systems? Shed their leaves and create their own mulch!!! Different types of
microorganism food (a.k.a. organic fertilizers... instead of thinking about
dumping nutrients on the plants, think about feeding the microorganisms)
favor either bacteria or fungi, and mulches tend to favor fungi. Trees prefer
nitrogen from fungi and they are smart enough to fertilize themselves!
Plants In Charge, Part 2
It goes even further than that. Plants need a few other things besides
nutrients and protection from pests. They need air and water. The
microorganisms give them that too. When the bacteria produce slime or fungi
grow into long hyphae or earthworms produce castings (the nicer word for worm
poop), they make the tiny particles of sand, silt, and clay in the soil and
make them stick together.
The clumps of particles have little crevices all over which leave room for
air and adhere to little bits of water. Not much of each, but some. These
little clumps give texture (or crumb structure) to the soil. It's not a bunch
of cement hard dirt or totally loose sand that blows away in the wind. In
other words, it prevents erosion.
Some of the other critters on the soil - earthworms for example - tunnel
through the soil aerating it even further. When it rains, the rain is able to
pass through the soil (it won't just run off or evaporate off the surface)
and little bits of water adhere to each of the tiny crevices in the soil,
eventually flowing deeper and deeper until it hits the groundwater.
Consider soil with a rich and healthy soil food web vs. dead, cement-like,
compacted dirt. Imagine during the rainy season they get 10 rainstorms with
an inch of rain each time. Each time the plants use 50% of the water (I'm
making these numbers up - they won't be realistic but the general theory is
one I've read in a similar example in a book - Holistic Management by Allan
Savory - so I'm pretty confident the overall concept is correct).
In the healthy soil, half an inch of water stays in the soil. In the dead
dirt, it runs off and/or evaporates. Each time this repeats. At the end of
the rainy season, the healthy soil has 5 inches of rain stored up and the
dead dirt has none. The healthy soil can continue growing (providing other
conditions are OK, like the temperature) even after the rains stop and it
will have leftover moisture to start growing again earlier in the next year
before the rains start. The dead soil can't.
Also, the healthy soil can withstand both drought and heavy rains better.
Because it holds water well, it has the capacity to hold a huge deluge of
rain but it also stores water better to use it during periods of drought.
Dead dirt does neither.
The Soil Food Web and Pests
The book makes it clear that no garden or farm will exist as pest-free. The
bad guys live among the good guys no matter what. The good news is that the
good guys EAT the bad guys. They also compete with them for resources and
habitat. When there is a void of life (such as after you use a pesticide that
kills everything indiscriminately), the bad guys can move in without anything
stopping them. With your health soil food web in place, you've got the good
guys in place to control the bad guys.
What This Means For Our Society
Does this just absolutely blow your mind? Think about how advanced all of
this is. Those who reject "modern" industrial agriculture are not Luddites at
all. Perhaps they never looked through a microscope but they are using
extremely complex science to grow their crops far better than industrial
methods ever could!!!
The real Luddites are the idiots (a.k.a. most of America) that uses the
industrial chemicals. First of all, many agricultural chemicals are derived
from petroleum, so GREAT JOB everybody - you found another reason to use
foreign oil. Let's keep fighting wars in the Middle East! They are also
processed and shipped using some form of energy (probably not renewable or
clean) too.
Second of all, they kill off the soil food web. They take the plants'
mechanisms for feeding and defending themselves away. They leave the plants
starved for nutrients and defenseless against pests. They leave the soil
totally dead and empty, with no competition for pests who want to move in.
They also kill off the organisms that live on the microorganisms - for
example, birds who eat worms and bugs who eat microorganisms are all denied
their food.
Third, the fertilizer runs off into waterways or leaches into the ground
water. So does the pesticide. There are many areas of the country where the
drinking water contains atrazine (a pesticide used widely on corn). Much of
the fertilizer makes its way into the Mississippi and then into the Gulf.
It feeds LOTS of algae, which in turn sucks the oxygen out of the water,
creating a condition called hypoxia. The result? A dead zone in the gulf the
size of New Jersey. If you can't swim away, you die. And guess what - as this
ridiculous ethanol craze fuels the demand for corn (a crop that farmers drown
in excess fertilizer), the dead zone will get bigger.
Another implication? This industrial method (plus some of our more
irresponsible and pro-Monsanto/DuPont/Exxon/ADM/Cargill/Tyson/etc laws) leads
to larger, more consolidated farms. It happens for a few reasons. For one,
one must purchase such expensive equipment to do this sort of farming that
they must spread out their overhead over a whole lot of volume in order to
come out ahead. Second, due to cycles of booms and busts in commodities
markets, more and more farmers go broke and sell off their smaller parcels to
larger farmers.
Why should you care? Because study after study shows that smaller family
farms benefit communities much more than enormous industrial farms. They
differ in size, organizational structure, and other facets, but the key
difference is that small farms are typically owned, managed, and worked by
one group of people whereas large farms are owned by one group, managed by
another, and worked by a third.
The large, industrialized model creates a stratified society with a gap
between rich and poor. In studies this leads to social disruptions (crime,
divorce, teen pregnancy, high school drop outs) and lowers the tax base which
erodes the local schools and community services. Yikes! So it matters to all
of us what type of farms we have - not just the farmers!
The current system benefits the powers that be: biotech firms, chemical
companies, big ag, processed food manufacturers and the retailers that sell
their cheap crap, oil companies, and so forth. The last thing they want is
for us to change our society in a way that benefits the earth and our quality
of life at the expense of their bottom lines. You've got nothing on this,
Eliot Spitzer!
We need to fight back!
What Do We Do About This?
Well, to start, inform yourselves! You've read this diary so you know the
basics. If you find it interesting, go get the book I mentioned in the intro
and learn more. The book gives specific gardening tips such as how to make a
compost tea and when to apply it. Forward the information around. Loan your
book to everyone you know or buy it for them as a gift.
Beyond that, here's a simple list of action steps (just in time for Earth
Day):
1. Arm yourself with information and spread the word!
2. If you have a lawn, stop using pesticides and fertilizers on it if you
do. Take the tips in the book I recommended. If you don't want to read the
book, get your lawn aerated and brew up some actively aerated compost tea and
apply it. Let leaves fall under trees and stay there. Leave grass clippings
on the lawn.
3. If you have a garden - first of all, good for you for growing your own
food! Second of all, stop using pesticides and fertilizers if you use them.
Then - same advice as before. Start reading and nourish your soil food web to
put it to work for you.
4. Garden. Even if it's just herbs in a pot as a start. They are hard to
kill if you add compost, put them in a sunny spot, water them frequently, and
keep your cats out of the way.
5. Compost!!! You can do this in a small apartment even with a worm bin or
a small compost bin on a patio. I've done it like that before. If you can't
keep a compost bin yourself, see if a friend or local business will compost
for you. I drop my food scraps and junk mail into the compost at Whole Foods.
6. Go to http://www.localharvest.org and search for a nearby CSA
(community supported agriculture) or farmers market. Buy as much food as
possible from local, organic sources who do not patronize the huge
corporations that are messing up our country!
7. Buy organic when you can. It's good to support farmers who don't
support Monsanto, etc.
8. Skip on the processed foods as much as possible. More processing = more
oil required from farm to fork. Yuck.
9. Stop rototilling (if you do so). The book I just read said that the
idea you need to rototill came from a boost in productivity when the
compacted soil was first aerated but after that initial boost, rototilling
does nothing good. It rips apart fungal hyphae and earthworms, thereby
hurting your soil food web. It also exposes weed seeds to sunlight.
10. Get active politically! I'll do my best to keep people here informed
but I recommend you also get your advice straight from the pros. An
organization I'm a big fan of is the Community Food Security Coalition. I
rely on their emails for my info because they are not too frequent and very
easy to understand. It saves me from having to watch C-SPAN.
Another source for info is http://www.recipeforamerica.org. Marrael set the
site up and Anais contributed some content too. I do my best to keep the site
up to date (I'm particularly good about adding links but less good about
writing new pages). It's designed to be a Kossack's guide to all food issues
so everyone here knows what to ask for from their congresscritters. Everyone
here is welcome to comment on the site to suggest additions and changes.
Some bills happen on a local level, and sometimes things won't even happen in
the form of bills. If you're a parent, get involved at your kids' school. See
if they will start up a school garden and integrate it into the science
curriculum. There are a few states with laws supporting school gardens too
(CA and OR) and Washington just passed a bill promoting local food in WA
schools. Very exciting!
Can you imagine the large scale societal change if we understood and
respected the soil food web? We'd eat different foods altogether - less
grain-fed meat and processed foods (the exact stuff that makes us fat) - and
we'd live in a cleaner, healthier world. We'd have less need for oil and
therefore less need for wars in the Middle East and less work to do to fix
global warming. We'd have healthier communities in an economic and social
sense too. All in all, life would be better.
If this is nothing but a win-win-win-win for everyone except for Monsanto and
Exxon, then why don't we get started today??? Yep - Monsanto, Exxon, and all
the rest - and the politicians they control. But if we start by spreading the
word about the role of the soil food web the way most people in America
understand global warming, we'll be a step ahead of where we are now.
- [Livingontheland] The Soil Food Web: The Dirtiest Scandal of All, Tradingpost, 07/25/2008
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