Remediation of stratified soil acidity through surface application of lime in no-till cropping systems

Carol McFarland, David R. Huggins, Kurt L. Schroeder, J. Joey Blackburn, L. Carpenter-Boggs, Rich Koenig, Timothy C. Paulitz

Introduction:• Accelerated soil acidification resulting from application of ammonia-based

fertilizers has been an issue of increasing concern in the Palouse region of Eastern Washington and Northern Idaho (Mahler et al., 1985)

• Low soil pH reduces crop yield as acidic conditions release phytotoxic levels of aluminum (Al) and manganese (Mn)

• Soils that developed under native prairie have greater base saturation, organic matter and increased buffering capacity to resist pH changes as compared to soils that developed under native forest

• In no-till systems acidification is often concentrated in a stratified band where fertilizer has been placed

• Traditional incorporation of liming materials is not possible for producers wanting to maintain no-till management systems

• Surface application of lime has been shown to remediate stratified acidic conditions (Caires, 2005)

• Recent availability of an ultra-fine (1-2 micron) fluid lime may help growers address stratified soil acidity issues

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Soil

dep

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Soil pHSoil pH stratification 0-30 cm at two sites

Rockford (Historically forested) PCFS (Historically prairie)

Methods:• Two sites representative of soils that were historically forested (Rockford) or in

native prairie (PCFS) prior to agricultural cultivation• November 2013 application of two calcium carbonate sources to experimental

field plots in a Complete Randomized Block Design• Ultra-fine (1-2 micron) particle size fluid lime (NuCal), applied with

a sprayer at rates: 224 kg ha¯¹, 448 kg ha¯¹, 1120 kg ha¯¹ and 2240 kg ha¯¹ calcium carbonate equivalent

• Sugar lime – byproduct of sugar beet processing, shaken onto the soil surface at rates: 448 kg ha¯¹ and 2240 kg ha¯¹ calcium carbonate equivalent

• Spring soil sampling from 0-10 cm divided into 2-cm strata• Above-ground biomass was taken at anthesis stage from each plot by hand

with a 1m² quadrat• Chickpea yield was harvested using a plot combine in 1.52m x 9.14m strips

Objective: Assess surface application of fluid lime and sugar lime on crop and soil properties in no-till cropping systems with stratified soil pH

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Soil

Al m

g kg

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KCl Al vs pH PCFS

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KCl Al vs pH Rockford

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Mn

mg

kg¯¹

Soil pH

DTPA Mn vs pH PCFS

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DTPA Mn vs pH Rockford

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Control FluidLime

224 kgha¯¹

FluidLime

448 kgha¯1

FluidLime

1120 kgha¯1

FluidLime

2240 kgha¯1

SugarLime

448 kgha¯1

SugarLime

2240 kgha¯1

Al m

g kg

¯¹

Al concentrations in above ground biomass with lime treatments

Chickpea Canola

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Control FluidLime

224 kgha¯¹

FluidLime

448 kgha¯1

FluidLime

1120 kgha¯1

FluidLime

2240 kgha¯1

SugarLime

448 kgha¯1

SugarLime

2240 kgha¯1

Mn

mg

kg¯¹

Mn concentrations in above ground biomass with lime treatments

Chickpea Canola

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Discussion:• Soil pH is an important parameter of soil quality, particularly for nutrient availability and

toxicity• Fall lime treatment increased pH in the 0-2 cm soil surface at both sites

within six months• Availability of Al to the plant can result in phytotoxicity with symptoms such as root-

stunting, which limits uptake of water and nutrients• Aluminum phytotoxicity is dependent on the concentration, species, availability and

activity of Al in soil (Brown et al., 2008) and the tolerance of plant species, and varieties which varies widely with a range of adaptive mechanisms

• At soil pH values under five, Al concentration increased exponentially at both sites

• A significant reduction in soil Al was seen at the 0-2 cm depth with lime treatment both sites

• The surface applied lime treatments did not significantly decrease levels of Al in plant tissue and in chickpea, concentrations were within the toxic range of 50-200ppm (McBride, 1994)

• Mn is an important co-factor in many plant enzymes with a significant role in the TCA cycle, but in high concentrations it can compete with Ca and Mg and be toxic

• Concentration of Mn in the soil solution is critical to phytotoxicity (Marschner, 2011)• Plant growth can be inhibited at dry tissue concentrations ranging from 200 mg kg¯¹ to

5300mg kg¯¹ (Marschner, 2011)• Surface application of lime significantly reduced Mn concentrations in

both the soil and the plant at both sites• Significant differences in crop biomass and yield were not seen during the 2014 season.

This may be because of high variability of the data, or Al toxicity was not inhibiting plant growth. Al may not be present at sufficient levels or species to cause toxicity. Alternatively, it may be chelated by high levels of organic matter present in no-till systems (Brown et al., 2008). It is also likely that the effects of lime surface applications have not yet reached the critical root zone

References:Brown, Tabitha T., Richard T. Koenig, David R. Huggins, James B. Harsh, and Richard E. Rossi. “Lime Effects on Soil Acidity, Crop Yield, and Aluminum Chemistry in Direct-Seeded Cropping Systems.” Soil Science Society of America Journal 72, no. 3 (2008): 634. doi:10.2136/sssaj2007.0061.Caires, Eduardo F., Luís R. F. Alleoni, Michel A. Cambri, and Gabriel Barth. “Surface Application of Lime for Crop Grain Production Under a No-Till System.” Agronomy Journal 97, no. 3 (2005): 791. doi:10.2134/agronj2004.0207.Mahler, R. L., A. R. Halvorson, and F. E. Koehler. “Long-Term Acidification of Farmland in Northern Idaho and Eastern Washington 1.” Communications in Soil Science & Plant Analysis 16, no. 1 (1985): 83–95. Marschner, Horst. Marschner’s Mineral Nutrition of Higher Plants, Third Edition. 3 edition. London ; Waltham, MA: Academic Press, 2011.McBride, Murray B. Environmental Chemistry of Soils. New York: Oxford University Press, 1994.Sparks, Donald L. Soil Science Society of America, American Society of Agronomy, and G.W. Thomas. Methods of Soil Analysis. Part 3, Chemical Methods. Madison, Wis: Soil Science Society of America, 1996.Van Lierop, W. “Chapter 5: Soil pH and Lime Requirement Determination.” In Soil Testing and Plant Analysis, 73–120. SSSA 3. Madison, Wis: Soil Science Society of America, 1990.

• Soil pH 1:1 water (vanLierop, 1990)

• KCl extractable Al• DTPA extractable

Mn (Gambrell, 1996)

• Plant biomass was dried and ground and sent to a certified laboratory for analysis of Al and Mn

• Statistical analysis was done using SAS 9.3 with Tukey LSD significance of 0.1

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Soil

Dep

th (

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KCl Al mg kg¯¹

Spring soil Al after fall surface lime treatments at PCFS

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Spring soil Al after fall surface lime treatments at Rockford

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Soil

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Mn mg kg¯¹

Spring soil Mn after fall surface lime treatments at PCFS

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Mn mg kg¯¹

Spring soil Mn after fall surface lime treatments at Rockford

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Acknowledgements:

Funded by the Washington Grain Commission. Thanks to the Huggins lab crew for technical support!

Results:• There was no significant difference between the lime treatments with chickpea or canola

above-ground biomass, or chickpea yield (data not shown)

Concentration of soil exchangeable Al at the surface depth (0-2 cm) was reduced significantly between the highest (2240 kg ha¯¹) and control treatments at both sites. At Rockford we saw a difference between the 224 kg ha¯¹ rate and the 2240 kg ha¯¹ of fluid lime but not the same rate of sugar lime

Concentration of Mn at the surface depth (0-2 cm) was reduced under the 2240 kg ha¯¹ rate of fluid lime at both sites as well as sugar lime at PCFS

• Plant tissue concentrations of Al showed no significant differences between the treatments

• Plant tissue concentrations of Mn were significantly different between the control and 2240 kg ha¯¹ rate of sugar lime

Soil pH at the surface depth of 0-2 cm, increased significantly between the 2240 kg ha¯¹ rate application of both lime sources and the controls

As pH decreased Mn increased at PCFS and at both sites Al increased exponentially

Above map from R. Koenig: used with permission

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Soil

Dep

th (

cm)

Soil pH

Spring soil pH after fall surface lime treatments at PCFS

Control

Fluid Lime 224 kg ha¯¹

Fluid Lime 448 kg ha¯1

Fluid Lime 1120 kg ha¯1

Fluid Lime 2240 kg ha¯1

Sugar Lime 448 kg ha¯1

Sugar Lime 2240 kg ha¯1

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4.25 4.75 5.25 5.75 6.25Soil pH

Spring soil pH after fall surface lime treatments at Rockford

Control

Fluid Lime 224 kg ha¯¹

Fluid Lime 448 kg ha¯1

Fluid Lime 1120 kg ha¯1

Fluid Lime 2240 kg ha¯1

Sugar Lime 448 kg ha¯1

Sugar Lime 2240 kg ha¯1

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