The Sleeping Beauty Paradox a metaphorical model of soil biotic interactions

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The Sleeping Beauty Paradox a metaphorical model
of soil biotic interactions
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Joel Gruver NC State University Department of
Soil Science
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Paraphrased from The Farmer as a
Conservationist by Aldo Leopold
In a surprising number of men there burns a
curiosity about machines and loving care in their
construction, maintenance and use.
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This passion for mechanisms, even though often
clothed in greasy overalls, is the pure fire of
intellect.
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Few realize that an equal passion for the
mechanisms of nature is possible for some future
generation. No one dreamed one hundred years
ago that metal, air, petroleum and electricity
could coordinate as an engine.
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Few realize today that soil, water, plants and
animals are parts of an ecological engine,
subject like any other to malfunction if
improperly assembled or maintained.
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Our present skill in the care of mechanical
engines did not arise out of fear that they might
fail to work. Rather it was born out of curiosity
and pride of understanding.
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Two perplexing phenomena have long puzzled soil
ecologists
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Mean residence times for microorganisms are
hundreds of times longer in soil than in
laboratory cultures.
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Mean residence time for bacteria in lab
culture several hours to several
days Mean residence time for bacteria in
soil 6 18 months

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The metabolic capacities of soil microbial
communities greatly exceed available organic
substrates.
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Why do microorganisms behave so differently in
soil than they do in a petri dish ?
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The Sleeping Beauty Paradox
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Most of the pores where soil microorganisms
reside are either environmentally suppressive or
lacking in appropriate substrates.
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Soil microorganisms are very limited in their
ability to move within the soil matrix.
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As a result, most of the microorganisms in soil
are in a quiescent state
waiting
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for their Prince Charmings to arrive
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Soil hot spots
Drilosphere
Porosphere
Detritusphere
Aggregatusphere
Rhizosphere
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The rhizosphere effect
Rhizoplane
End of the rhizosphere
Endo-Rhizosphere
Root free soil
Ecto-Rhizosphere
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Priming effect of plant roots
AggregateDisruption
Exposition of organic matter
GrowingRoot
Priming Effect
Exudate
Active Biomass
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Nutritional interactions
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Soil fauna have very limited innate ability to
digest complex organic molecules.Soil microbes
have an almost unlimited digestive capacity.
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Microbial grazers Protozoa and nematodes harness
the digestive capacity of soil microorganisms by
grazing on microorganisms. Some meso and
macrofauna continue the cycle by grazing on
microfauna.
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Litter/residue transformers Many microarthropods
pass fecal pellets containing shredded but
largely undigested substrates. After a few days
of external rumen digestion, they reingest
their fecal pellets.
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Ecosystem engineers Most macrofauna utilize an
internal rumen digestion strategy.
Microorganisms in their gut enable them to gain
nutrition from very complex substrates.
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A hierarchical model for decomposition in
terrestrial ecosystems Climate ?? Inherent soil
properties ?? Plant community ?? Soil
macroorganisms ?? Soil microorganisms
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Effect of earthworms on SOM dynamics
Ingested soil
Fresh casts
Aging casts
Soil profile
Nutrient release
Assimilation Comminution
Physical protection
Acceleration of turnover
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Blechh !!! Tastes Bad !!!!
How do you expect to live off this stuff ???
I cant get if off, you try !!
Fe
Al
We already are !!!!!!
Yuck !!!!! Sure is gritty !
Theres gotta to be a way inside !!!
Hey !! Theres good stuff in there !!!!
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Trilogy of ecological managementConservationAug
mentation Activation
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The End