Soil Health & Tillage Long-term Impacts Francisco J. Arriaga Soil Science Specialist Dept. of Soil Science & UW-Extension E-mail: farriaga@wisc.edu Office phone: 608-263-3913
Functions of Soil & Soil Health Soil health 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. (Karlen et al., 1997) source: Brady & Weil, 1996
Soil Functions Indicators Medium for plant growth Recycle/store nutrients & organic materials Habitat for soil organisms Water storage & purification Texture Structure Infiltration & bulk density Water holding capacity Aggregate stability Soil organic matter ph Extractable N,P, & K Microbial biomass C & N Potentially mineralizable N Soil respiration
Soil Properties Affected by SOM Physical infiltration water retention hydraulic conductivity bulk density Chemical CEC nutrient availability buffering capacity source: soilquality.org A2809 Table 6.3
(Lado, Paz and Ben-Hur, 2004)
Role of Soil Organic Matter Physical soil properties Chemical soil properties Sands: 3 5 meq/100 g Silt loam: 15 25 meq/100 g Clays: 20 50 meq/100 g Organic soils: 50 100 meq/100 g Source: Magdoff and van Es, 2009
How is Soil Organic Matter Lost? Moldboard No Till Cumulative CO 2 (kg C/ha) 2500 2000 1500 1000 500 0 0 10 20 30 40 50 60 70 80 Time Since Plowing (days) (Rochette and Angers, 1999)
Farming for Soil Organic Matter (adapted from National Academy of Sciences, 2009)
Tillage Trends: 2000 2010 WDATCP WinTransect Data - Corn Tillage 2000 2005 2010 ----------------------------- % ------------------------------ No-till 11 22 29 Chisel 39 33 58 Moldboard 49 43 5 Other 1 2 8
Tillage Trends: 2000 2010 WDATCP WinTransect Data - Soybean Tillage 2000 2005 2010 ----------------------------- % ------------------------------ No-till 29 46 49 Chisel 39 34 38 Moldboard 22 19 5 Other 10 2 8
Corn Yield Tillage: conventional reduced no-till (Stine & Weil, 2002)
Water Availability for Crops Water infiltration of five different tillage systems NT=No-till ST=Strip-tillage (in-row) DR=Deep Rip CP=Chisel Plow MP=Moldboard Plow (Al-Kaisi, 2011) Approximately ¼ of water is lost from the soil with every tillage pass. source: M. Licht & M. Al-Kaisi, 2013
SOM & Soil Water Retention Plant Available Water (PAW = FC PWP) 40 WP % silt loam Soil Water Content, % 30 20 10 FC % 2.2 2.3 2.4 2.5 2.5 2.6 2.7 Difference in Plant Available Water = 0.5 inches/ft 0 0 1 2 3 4 5 6 Soil Organic Matter, % 40 WP % loamy sand Soil Water Content, % 30 20 10 FC % 0.9 0.8 0.9 1.0 1.0 1.1 1.2 Difference in Plant Available Water = 0.3 inches/ft4 0 0 1 2 3 4 5 6 Soil Organic Matter, %
Recharging the Soil Profile with Water photo: Prairie Fire, Aug 2010 Corn stalks of 12 in height can hold snow in the field, and has been estimated to account for 1 to 2 of additional water in the soil profile. source: M. Licht & M. Al-Kaisi, 2013
Why Does Soil Health Matters? Eroded field example: source: S. Papiernik, 2013
Why Does Soil Health Matters? source: S. Papiernik, 2013
Why Does Soil Health Matters? source: S. Papiernik, 2013
Why Does Soil Health Matters? cont. Erosion level - Slight - Moderate - Severe Source: Arriaga and Lowery, 2003a
How Can the Health of a Soil be Improved? Measurement Organic matter Infiltration Aggregation ph Microbial biomass Forms of N Bulk density Topsoil depth Available nutrients Process Affected Nutrient cycling, pesticide and water retention, soil structure Runoff and leaching potential, plant water use efficiency, erosion potential Soil structure, erosion resistance, crop emergence, infiltration Nutrient availability, pesticide absorption and mobility Biological activity, nutrient cycling, capacity to degrade pesticides Availability to plants, leaching potential, mineralization and immobilization rates Root penetration, water/air filled pores, biological activity Rooting volume, water and nutrient availability Capacity to support plant growth, environmental hazard (adapted from Karlen et al. SSSAJ, 1997)
It is About Management! Source: Case Quick Start Guide Licht & Al-Kaisi, 2004
Location: Arlington, WI Soil: Plano silt loam Long-Term Rotation Study Objective: determine tillage response in rotational systems that increase the amount of corn in the cycles Researcher: Joe Lauer, Corn Agronomist Treatments: Tillage: CT (chisel, 2x field cultivations) & NT Rotation: 14 sequences with corn & soybean that have every phase present every year (CC, CS & 5C-5S) source: J. Lauer, Agronomy Advice, July 2013 http://corn.agronomy.wisc.edu
Field Day August 2013
Water Infiltration Field Day August 2013 Conventional No-tillage photos: Roger Schmidt, NPM Program
Root Growth Field Day August 2013 Conventional No-tillage photos: Roger Schmidt, NPM Program
CT Roto-tilled NT Soil Organic Matter Field Day August 2013 Organic matter oxidation Conc. H 2 O 2 NT Roto-tilled CT Aggregate stability Slake test photos: F. Arriaga, Soil Science
Corn Yield Response to Tillage source: J. Lauer, Agronomy Advice, July 2013 http://corn.agronomy.wisc.edu
Crop Rotation & Tillage Interaction Years in Corn after 5-yrs of Soybean source: J. Lauer, Agronomy Advice, July 2013 http://corn.agronomy.wisc.edu
Fuel Use by Different Tillage Tillage Gallons per acre Cost per acre Chisel 1.10 $ 3.74 Disk, offset 0.95 $ 3.23 Disk, tandem (stalks) 0.45 $ 1.53 Disk, tandem (chisel) 0.55 $ 1.87 Disk, tandem (plowed) 0.65 $ 2.21 Field cultivate 0.60 $ 2.04 Harrow 0.35 $ 1.19 Moldboard 8 deep 1.68 $ 5.71 Strip-till 0.60 $ 2.04 Off-road Diesel $3.40 per gal Farm Economics Facts & Opinions 06-07 Univ. of Illinois Urbana-Champaign US Energy Information Administration, Nov 2013
Estimated Cost of Fuel for Tillage Operations - 2013 Tillage system Conventional Fuel cost of operation * - fall chisel operation $ 3.74 -------- $ per acre -------- - field cultivate (x2) $ 2.04 x 2 = $ 4.08 Total fuel tillage costs $ 7.82 No-tillage (direct seeding) $ 0 $ 0 DIFFERENCE - $ 7.82 * Assumes off-road diesel cost of $3.40 per gallon (US Energy Information Administration, Nov 2013)
Soil Temperature @ 2 Depth 100 Residue (%) 80 60 40 20 Chisel Strip-till No-till 0 Courtesy: R.P. Wolkowski source: R.P. Wolkowski
Tillage And Rotation Effect On Corn Yield Arlington, WI 1997 2007 (10 Year Avg.) 200 Chisel Strip-till No-till Yield (bu/a) 185 170 155-4 % -8 % -5 % 140 CC SbC source: R.P. Wolkowski
When to Consider Production Costs? ROTATION/TILLAGE AVG. YIELD (BU/A) COP ($/BU) COMPARED TO CH ($/BU) Continuous Corn Chisel 182 2.55 -- Strip-till 174 2.53-0.02 No-till 167 2.63 0.08 Corn after Soybean Chisel 194 2.39 -- Strip-till 194 2.27-0.12 No-till 185 2.36-0.03 Soybean after Corn Chisel 52 6.41 -- Strip-till 52 6.23-0.18 No-till 50 6.15-0.26 * - yield is an average from 1997-2007, Arlington WI (NHSS issue #2 2008, Wolkowski, Cox and Leverich)
Rotation & Tillage Effect on Corn 0 lb N/ac 50 lb N/ac 224 190 Corn Alfalfa Corn Soybean 224 190 Corn Alfalfa Corn Soybean 160 160 128 128 95 95 60 60 Grain yield, bu/acre 30 0 224 190 Corn Alfalfa 100 lb N/ac Continuous Corn Corn Soybean 30 0 224 190 Corn Alfalfa Continuous Corn 200 lb N/ac Corn Soybean 160 160 128 128 95 60 Continuous Corn 95 60 Continuous Corn 30 30 0 0 CC chisel, disk & cultimulcher CA no-till CS no-till (Stanger & Lauer, Agron. J. 2008)
Closing Remarks No-tillage (direct seeding)and other reduced tillage practices help protect the soil from erosion and improve soil health through increases in soil organic matter Overtime, these benefits can help improve economic returns. However, other management practices can affect the magnitude of these benefits.
Thank You! Any Questions? Francisco J. Arriaga E-mail: farriaga@wisc.edu Office phone: 608-263-3913