1. SOIL QUALITY ASSESSMENT
Bob Kremer & Kristen Veum
USDA-ARS Cropping Systems and Water Quality Research Unit
Columbia, MO
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, October 2012, Columbia, MO

2. SOIL QUALITY: functional capacity of soil to meet defined human needs by supporting optimal biological activity and diversity for economic production of crops and livestock, regulation of water flow and storage, and provision of environmental buffers.
SOIL HEALTH: continued capacity of soil as a vital living system whereby plant and animal growth and environmental quality is sustained; a holistic approach in which plant, animal, and human health is promote
Missouri
(Menfro silt loam)
Brazil (‘Oxisol’)
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, October 2012, Columbia, MO

3. Soil Quality Test Kit - landowner self-assessment of soil quality/soil health
USDA-NRCS, Soil Quality Institute Soil Quality Test Kit Guide.
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, October 2012, Columbia, MO

4. Soil Quality Assessment
Vital functions:
sustain biological activity, diversity, productivity
regulate/partition water and solute flow
filter, buffer, degrade, immobilize and detoxify organic/inorganic material
store and cycle nutrients within the biosphere
support socioeconomic structure, protect habitat
Soil Processes:
Biological
Chemical
Physical
Indicators:
Soil property measurements that are sensitive to detect changes in the functions or processes of concern; i.e., sensitive to land management practices
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, October 2012, Columbia, MO

5. Soil Management Assessment Framework
“SMAF” -
site-specific interpretation for soil quality assessment results
measured soil indicator data (scores) integrated into a “soil quality index”
index often correlates with value of other soil properties
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, October 2012, Columbia, MO

6. Soil Management Assessment Framework (SMAF) Soil Quality Index
Quantitative index using algorithms to calculate non-linear scores for each indicator variable ranging from 0-1
Scores are summed and averaged across indicators
13 available indicators representing 4 soil function groups:
Physical – aggregate stability, bulk density
Chemical – EC and pH
Nutrient – P, K and mineralizable N
Biological – SOC, microbial biomass-C, β-glucosidase
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, October 2012, Columbia, MO

7. Soil Management Assessment Framework (SMAF) Soil Quality Index
Uses Site-Specific Characteristics to Parameterize the Algorithms:
OM Class (WSA, SOC, β-GLU, P…)
Texture Class (WSA, SOC, BD, K, β-GLU, P…)
Fe2O3 Class (WSA…)
Climate Class (SOC, β-GLU…)
Mineral Class (BD…)
Slope Class (P…)
Weathering Class (P …)
Crop Optima (pH, P…)
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, October 2012, Columbia, MO

8. Soil Management Assessment Framework (SMAF) Soil Quality Index
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, October 2012, Columbia, MO

9. Soil Management Assessment Framework (SMAF) Soil Quality Index
Water Stable Aggregates Algorithm:
Y= a + b * cos (cx – d)
d = d1*d2*d3
d1 based on OM class
d2 based on textural class
d3 based on Fe2O3 class
a, b & c are fixed
x = WSA (%)
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, October 2012, Columbia, MO

10. Soil Management Assessment Framework (SMAF) Soil Quality Index
pH Algorithm:
Y = a * exp ((-(x-b)2) / 2*c2)
a = 1 (fixed)
b = optimum pH§
c = pH range §
x = pH
§ crop dependent
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, October 2012, Columbia, MO

11. Soil Management Assessment Framework (SMAF) Soil Quality Index
Example using Centralia Plots (3 reps each) – Fall 2010
Minimum Till Corn – No Till Soy (MTC-NTS)
No Till Corn – No Till Soy (NTC-NTS)
Integrated Crop Mgt - Wheat (cover) - Corn (cover) – Soybean (ICM-WCS)
Switchgrass (SG)
Cool-season grass/legume (CRP)
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, October 2012, Columbia, MO

12. Soil Management Assessment Framework (SMAF) Soil Quality Index
SMAF Variables Selected (6)
Soil Phosphorus
Extractable Potassium
Water pH
Bulk Density
Soil Organic Carbon
Water Stable Aggregates
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, October 2012, Columbia, MO

13. Centralia SMAF Scores by Cropping System and Landscape Position
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, October 2012, Columbia, MO

14. Centralia SMAF Scores by Cropping System (averaged across landscape positions)
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, October 2012, Columbia, MO

15. Sanborn Field SMAF Example
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, October 2012, Columbia, MO

16. Selected SMAF References
Stott, D.E., C.A. Cambardella, R. Wolf, M.D. Tomer, and D.L. Karlen A soil quality assessment within the Iowa River South Fork Watershed. Soil Science Society of America Journal 75: doi: /sssaj
Stott, D.E., S.S. Andrews, M.A. Liebig, B.J. Wienhold, and D.L. Karlen Evaluation of β-glucosidase activity as a soil quality indicator for the Soil Management Assessment Framework (SMAF). Soil Science Society of America Journal 74: doi: /sssaj
Karlen, D.L., G.E. Varvel, J.M.F. Johnson, J.M. Baker, S.L. Osborne, J.M. Novak, P.R. Adler, G.W. Roth, and S.J. Birrell Monitoring soil quality to assess the sustainability of harvesting corn stover. Agronomy Journal 103:288. doi: /agronj s.
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, October 2012, Columbia, MO

17. Active Carbon Analysis
Active C Assay
Active carbon fraction:
microbial biomass carbon
particulate organic matter
soil carbohydrates
Drives the soil food web; influence nutrient cycles and biological soil properties
Active carbon fractions indicate soil rresponse to different management systems
Compared to total organic C, active C may be more sensitive to management practices and more closely related to soil productivity and biological soil properties such as respiration, microbial biomass and aggregation.
See “Active C & SOC – Sanborn Field” pdf for comparison analyses of soils from long-term management plots at Sanborn Field – Tables 2 &3
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, October 2012, Columbia, MO

18. C\Sustainable Ag\SustainableSoil Lecture-08
SOIL QUALITY ASSESSMENT
‘Biologically-active soil C’ better describes SQ than total SOM;
Detected via oxidation of C by dilute permanganate, thus reagent color disappearance indicates higher C
‘Conventional Cultivation’
‘Grass Pasture’
‘Native Prairie’
Development of easy, quick, in-field test, based on color difference when reagents mixed with soils, for use by farmers is underway. Soils collected from fields under different management within the watershed will be assessed for effects on biologically-active C and, thus, Soil Quality.

19. C\Sustainable Ag\SustainableSoil Lecture-08

20. Active Carbon Analysis
Active C in soil extract can be quantitatively measured in field using a hand-held meter (spectrophotometer)
Hach Company Instruments
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, October 2012, Columbia, MO