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Ray Archuleta

Conservation Agronomist

NRCS-ENTSC

2901 East Lee Street

Greensboro NC 27313

336-662-5908

Ray.Archuleta@gnb.usda.gov

NRCS-ENTSC National Soil Quality team

Participants will be able to list and describe:

1) How physical, chemical, biology disturbance impacts soil function

2) How soil biology impacts soil function3) Case studies throughout the country that

farm in nature’s image and utilize manureaccordingly…

4) What are the common management principles this agriculture practitioner’s apply

Soil health/quality is the capacity of a specific kind of soil to function, within natural or managed ecosystem boundaries, to sustain plant and animal productivity, maintain or enhance water and air quality, and support human health and habitation.

USDA NRCS

Soils perform five board ecological functions:

1) Principle medium for plant growth2) Regulate water supplies3) Recycles raw materials and waste products4) Serves as engineering medium for human

built structures5) Habitat to many living organisms- a major

ecosystem in its own right.

The Nature and Properties of Soil 13th edition, page 45 Nyle C. Brady and Ray R. Weil

.

Context Builds Understanding:

your experience of a situation

depends

on the context within which

you interpret that situation.

Ecology:

the study of

relationships between

people, animals, and

plants, and their

environment.Interconnectedness

Soil Surface

Focus On Nature’s Similarities then Dissimilarities

Africa

Virginia

Battle Starts Here

North towards New Jersey: 2008

Flying north towards Jersey: 2008

Conservation Tillage ?

Urban DisturbanceAgriculture Disturbance

Lake A-T-Lax: 14 miles SW of High Point NC

No Cover: Near Columbus Ohio

Oct 2010

Bulk Density of Soils in New Jersey

Reference: Bulk Density for Concrete is 2.4 g/cm3

Clear runoff

from no-tilled

field

No-tilled fieldConventional-tilled field

Sediment runoff from

conventional-tilled field

Impact of disturbed Aggregates

Continuous

GoodRotational

Excellent Rotational

Disrupted Soil Ecosystem

This soil is naked, hungry, thirsty and running a fever!

Ray Archuleta 2007

Endogeic earthworm in aestivation, occurs when the soil

is too hot, cold or dry

Soil Temperatures

Bare SoilFull Crop Canopy

Ambient Air Temperature = 105 Degrees F

When soil temperature reaches...

140 F Soil bacteria die

130 F 100% moisture is lost through

evaporation and transpiration

113 FSome bacteria species start dying

100 F 15% of moisture is used for growth85% moisture lost through evaporationand transpiration

95 F

70 F 100% moisture is used for growthJ.J. McEntire, WUC, USDA SCS, Kernville TX, 3-58 4-R-12198. 1956

C

Energy flow, Water cycle, Bio-Community Dynamics and the Biogeochemical nutrient cycle

At the field level: Tillage disrupts this

Ecosystem Processes!

NPK

Ray Archuleta

Loss of SOM as CO2

CO2CO2CO2

PHYSICAL DISTURBANCE: Tillage induces the native bacteria to consume soil carbon; byproduct is C02.

Tillage disrupts Drilo-Poro-Detritus-Rhizo-and the Aggregtus-sphere

M = Mobile

R. = Research

G = Gas

E = Exchange

M = Machine

MR. GEM

Invisible effects of invisible forces!

Reicosky et al., 1995

Reicosky et al., 1995

Subsoil tillage Mold bold tillage Chisel tillage

Different tillage = Different rates of SOM loss

CO2

SOM loss

Mold bold plow Chisel plow

3X 2X 1X

Reicosky,2000

Tillage

CT NT2 NT8 NT40

Mic

rob

ial

bio

ma

ss

C (

lbs

/ac

)

100

200

300

400

0-7.5 cm

7.5-15 cm

15-22.5 cm

22.5-30 cm

Tillage p<0.001Depth p<0.001Interactions p<0.21

Microaggregate20-90 µm

90-250 µm

Plant and fungi debris

Microaggregate Silt+Clay

Microestructure of clay

Particulate organic matter

Fungi hyphae

Macroaggregate

Basic components of macroaggregate

Adapted from Tisdal and Oades 1982; Mikka and Rice, 2004

Mechanical disturbance by tillage disrupts aggregation, exposes SOM protected within the aggregates to microbial attack

The decrease of SOM within the aggregates due microbial attack causes dispersion of clay

particles, clay microstructure and silt+clay microaggregates

Forest SOM = 4.3 %

CT 17 yr- Soybean monoculture SOM = 1.6 %

20

cm

la

yer

What happened to this soil?

62.8% loss of SOM after 17 yr intensive

tillage

Black Box Syndrome

H+NO3

-

K+

Soil Solution

Ca++

Fe++

HPO4--

BO3--

SO4--

O2CO2

NH4+

P2O5H2PO4

-

Dennis Froemke

ND Area Range Specialist

vasicular-arbuscular

mycorrhizal (VAM) fungi

Rhizosphere

Dennis Froemke

ND Area Range Specialist

Dr. Kris Nichols, Microbiologist, ARS, Mandan, ND

Hierarchical Understanding on How Biodiversity Improves Soil Functions!

M.H. Beare, D.C. Coleman, D.A. Crossley Jr., P.F. Hendrix and E.P. Odum (1995)

Destructive release of nutrients: Constructive release of nutrients:

Tillage: Disking, Plowingand other high soil disturbanceActivities.

Plant Roots:Exudates

Commercial l Fertilizer : Over use in low carbon soils (tilled) or buffered soils.

Soil Organism Predation:

Fallow Fields: (Leaky system) Manure or Compost:

Fire Crop Residueor plant litter:

Priming effect: soil releases nutrients to plant

Various Sources

Martin Alexander 1967 Intro to Soil Microbiology

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What can the plant access alone?

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Collaboration between root fungus and roots

What Impacts the Mycorrhizae?

1. Tillage- diminishes hyphae and spores

2. Fallow periods-minifies spore populations

3. Burning stubble-kills spores on soil surface

4. Poor soil drainage-reduces population

5. Fungicides-extremely toxic6. Most herbicides or pesticides applied

at recommended rates have little effect on mycorrhizae.

Soil Microbiology: Mark Coyne 1999

20 years of similar tillage intensity and C inputs

but contrasting types of organic inputs

Crop residues

Cover Crops

Animal manure

Crop residues

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