Source: UNIVERSITY OF KENTUCKY submitted to
SOIL PRODUCTIVITY AS AFFECTED BY MECHANICAL INFLUENCE
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0203900
Grant No.
(N/A)
Project No.
KY005023
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Oct 1, 2005
Project End Date
Sep 30, 2010
Grant Year
(N/A)
Project Director
Wells, L. G.
Recipient Organization
UNIVERSITY OF KENTUCKY
500 S LIMESTONE 109 KINKEAD HALL
LEXINGTON,KY 40526-0001
Performing Department
BIOSYSTEMS & AGRIC ENGINEERING
Non Technical Summary
Machinery traffic can cause adverse compaction of cropland that results in reduced yield. The purpose of this research is to develop a means of preventing adverse compaction of soil during reconstruction after mining and to determine an optimum procedure to identify and ameliorate adverse soil compaction in conventional cropland.
Animal Health Component
50%
Research Effort Categories
Basic
(N/A)
Applied
50%
Developmental
50%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
1020110106040%
1021510106010%
1021549106010%
1021820106010%
4025310202030%
Goals / Objectives
1. To reconstruct an excavated soil mass using a mechanical system that avoids traffic compaction and to determine a preferred procedure for soil placement and incorporation of amendments in such reconstruction. 2. To develop and verify a method of identifying adverse compaction in soils and specifying depth of required remendial tillage. 3. To determine whether variable-depth subsoiling is a cost-effective method of applying remedial tillage.
Project Methods
Objective 1: A mechanical system for reconstructing severely disturbed soil will be evaluated along with the potential benefit of adding organic matter to soil during reconstruction. Soil will be excavated from a 1 ha (2.5 ac)site at the University of Kentucky Animal Research Center and reconstructed to a maximum depth of 1.22 m (48 in.). Treatments will include both mixing and separating original A and B horizons, with and without adding organic material. Soil physical properties will be measured as will three years of corn yield. Objectice 2: Three cropland sites with suspected adverse soil compaction will be identified and mapped into 0.4 ha (1 ac) grid cells using GPS. Near-infrared imagery, mechanical impedance and electrical conductivity will be compared for determining the existence of adverse soil compaction as indicated by soil cone index (CI) > 2 MPa (290 psi). Objective 3: The efficacy of precision deep tillage to ameliorate adverse soil compaction will be investigated. Soil grid cells with average CI > 2 MPa (290 psi) will be divided into three treatments; tilled to maximum depth of CI > 2 MPa (290 psi), tilled to 40 cm (15.7 in.), and not tilled. Crop yields will be compared for three years at the three sites.

Progress 10/01/05 to 09/30/10

Outputs
OUTPUTS: A second year of acquiring corn yield data from reconstructed soil plots was completed. Corn will be grown on the plots again in 2011 to complete a 3-year study. Publication of the results should occur in late 2011 or early 2012. PARTICIPANTS: L.Wells, Professor, and T. Stombaugh, Associate Extension Professor, Biosystems and Agricultural Engineering and T. Mueller, Associate Professor, Agronomy, , University of Kentucky, Lexington, KY TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
A paper was submitted for publication in Applied Engineering in Agriculture which described the operation of a mechanical soil reconstruction system. The paper documents system capacity and performance characteristics. This information, when combined with results of corn yield studies, should indicate that successful reclamation of severely disturbed cropland is feasible and cost effective.

Publications

  • No publications reported this period


Progress 01/01/09 to 12/31/09

Outputs
OUTPUTS: Field measurements were collected during April-May 2009 to evaluate the utility of the soil coulterometer which has been developed as a component of this project. Soil coulterometer measurements were recorded along separate transects across a field at depths of 4, 8 and 12 in. Soil cone index and soil bulk density were measured at 75 discrete locations along each transect at the corresponding depth. Correspondence of coulterometer measurements to these locations was accomplished by comparing DGPS coordinates. Correlation between coulterometer indices and both soil cone index and dry bulk density was poor. The experiments will be repeated in 2010 using more precise correspondence of measurement locations. A preliminary evaluation of the soil coulterometer as a predictor of soil bulk density and cone index was published in Applied Engineering in Agriculture. Corn yield was measured on plots reconstructed by a mechanical soil replacement system in 2009. A randomized block design was utilized in which 4 reconstruction treatments (separating or combined A & B horizons, with and without 22 tons/ac organic matter) were applied in triplicate. The average yield was 233 bu/ac and the range was 192 to 265 bu/ac. These measurements will be repeated in 2010 and 2011. PARTICIPANTS: Tom Mueller is an Associate Professor in the Department of Plant and Soil Sciences at the University of Kentucky. He can be contacted at mueller@uky.edu. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
The development of the soil coulterometer could be instrumental in the implementation of site specific remedial deep tillage. This system is intended as a cost-effective means of locating adverse soil compaction in fields so that site-specific remedial tillage can be applied. This approach offers substantial potential reducing energy use and improving production efficiency and profitability. The successful demonstration of the mechanical system for reconstructing cropland offers the potential of returning most or all cropland subjected to surface mining, or similar massive disturbance, to original productive capacity. The impact would be substantial in maintaining U.S. agricultural productivity. Tom Mueller's research group has been testing the Veris NIRS field spectrometer that was purchased with Hatch funding. They have conducted extensive testing in the laboratory and field. In the laboratory, they tested the instrument with the North American Proficiency Testing (NAPT) test soils. They found that they could predict carbon with the NAPT samples with an r2 value of 0.68 using simple linear regression (these results were based on a leave-a-subset-out validation analysis). They also are testing the spectrometer in probe and shank mode but these analyses have not yet been finalized. Additionally, they are comparing the Veris spectrometer with a research grade laboratory spectrometer.

Publications

  • Pitla, S.K., L.G. Wells and S.A. Shearer. 2009. Integration of an extended octagonal ring transducer and soil coulterometer for identifying soil compaction. Applied Engineering in Agriculture 25(5): 647-652.


Progress 01/01/08 to 12/31/08

Outputs
OUTPUTS: Technology developed by means of the project was presented at the 2008 International Meeting of the American Society of Agricultural and Biological Engineers. The presentation was entitled 'A system to measure soil compaction "on-the-go" with minimal surface disturbance.' The presentation explained a system that is being developed to map adverse soil compaction in cropland so as to facilitate site-specific application of remedial deep tillage. Such technology should reduce energy expended in maintaining cropland productivity. The project also produced a master's of science graduate , Srikiran Bodapati, from Biosystems and Agricultural Engineering at the University of Kentucky. Mr. Bodapati's thesis, entitled 'Dynamic Mechanical Control System for Soil Reconstruction,' presented a method of controlling soil placement during reconstruction of surface-mined cropland. His contribution added an essential element to a process whereby severely disturbed soil can be reconstructed without compaction by earthmoving equipment. If implementd, this process can ensure successful reclamation of cropland after surface mining. PARTICIPANTS: Two individuals have received M.S. degrees while contributing to this project. Mr. Santosh Pitla contributed to the development and testing of an oscillating coulter to measure soil compaction. Mr. Srikiran Bodapati was primarily responsible for designing, assimilating and testing an automatic control system for soil placement during reconstruction. We have collaborated with Miles Enterprises, Inc. of Owensboro, KY during 2008. The recording 'soil coulterometer' was evaluated on one of their client's farms. We also collaborated with Peabody Energy regarding the possible evaluation of the soil reconstruction system on one of their surface mines near Evansville, IN during 2008. TARGET AUDIENCES: The target audiences for the 'soil coulterometer' are farmers or crop consultants. Mapping of soil compaction can be compared to crop yield maps to determine locations for site-specific remedial tillage. The target audience for the soil reconstruction system is surface mining enterprises. This system will hopefully alllow succcesful reclamation of cropland without increasing the cost of mining. PROJECT MODIFICATIONS: We have purchased the Veris VIS-NIR - Spectrophotometer with the shank and probe attachments. We have completed retrofitting a Giddings Probe to work with the spectrophotometer. We have begun to collect data in the laboratory. The relationship between absorption and soil water content at two water bands (1450 and 1926 nm) were found to be linear, with greater slope corresponding to the higher wave length. This winter we plan to continue testing in the laboratory with archived soil samples. In the spring, we will begin making measurements with the probe and shank units at a Farm in Shelby County Kentucky. Dr. Thomas Mueller, Department of Plant and Soil Sciences, is leading this part of the research.

Impacts
One project outcome was the determination that an instrumented coulter can be used to map soil bulk density and water content variation in the upper 30 cm of a soil. Further experimentation in 2009 will hopefully result in successful correlation of the soil coulter index to the widely accepted soil cone index with regard to characterizing the state of soil compaction. A second outcome of the project was the determination that the process of mechanical soil reconstruction can be automatically controlled so as to successfully deposit soil A- and B-horizons at appropriate depths while avoiding any mecahnical compaction. Further experimentation in 2009 will hopefully show that the system can be used without compromising necessary soil reconstruction capacity of commercial mining operations.

Publications

  • No publications reported this period


Progress 01/01/07 to 12/31/07

Outputs
OUTPUTS: An experimental device for assessing soil compaction was designed, fabricated and tested. A 32 in. diameter straight coulter was mounted on a two-directional force gauge to measure horizontal and vertical soil resistance. The coulter assembly was mounted on a tractor 3-point hitch and was oscillated vertically by the action of a hydraulic cylinder such that coulter depth continuously varied between 2 in. and 14 in. as the tractor moved forward. Vertical and horizintal soil resistance, coulter depth and GPS coordinates were recorded continously in order to map soil compaction in a field. Measurements of vertical and horizontal coulter soil resistance were compared to conventional soil cone penetrometer and soil bulk density measurements. Excellent correlation between both vertical and horizontal coulter resistance and soil bulk density was determined. Correlation between coutler resistance and soil cone index was less than expected, perhaps owing to inaccurate recording of penetrometer depth. These results were presented at the 2007 International Meeting of the American Society of Agricultural and Biological Engineers. A mechanical system for reconstructing severely disturbed soil (U.S. patent no. 6,056,066) was modified and tested. Approximately 1.5 ac of silt loam cropland was excavated to an approximate depth of 3 ft at a site on a University of Kentucky research farm. The experimental system was used to then reconstruct the soil while completely avoiding mechanical traffic and resultant compaction. The site was reconstructed using four treatments replicated three times. The treatments were: A- and B-horizons separated, no organic matter added; A- and B-horizons mixed, no organic matter added; A- and B-horizons separated, 22 tons/ac organic matter added; and, A- and B-horizons mixed, 22 tons/ac organic matter added. The mechanical system reconstructed soil at a maximum rate of approximately 850 cu.yds. per hour. These reults were reported at the 2007 Annual Meeting of the American Society of Mining and Reclamation. PARTICIPANTS: V.S Bodapati and S.K. Pitla will complete Master of Science degrees in Biosystems and Agricultural Engineering at the University of Kentucky as a result of their work on the project. Dr. T.G. Mueller, Department of Plant and SOil sciences has recently joined the project as a co-investigator. He will supervise development and assessment of methods of indirect measurement of soil physical and chemical properties. TARGET AUDIENCES: The target audiences of this project would be enterprises which facilitate site-specific management of crop production. This would include providers of fertilizers, chemicals and equipment used in site-specific crop production. An additional target audience would be enterprises involved in reconstructing soil follow surface mining or similar disturbance of cropland. PROJECT MODIFICATIONS: Dr. T.G. Mueller will supervise the evaluation of a Veris NIRS sensors to measure soil phyical and chemical properties. Measurements made with these sensors will be compared to the soil coulteromemter, soil cone penetrometer, and a nuclear soil moisture/density gauge.

Impacts
The 'coulterometer' will be submitted for potential patenting in 2008. If subsequent evaluation proves successful, the device could be used to inexpensively map potential adverse compaction in fields and provide the basis for site-specific remedial deep tillage. A proposal was submitted to the U.S. Office of Surface Mining to evaluate the mechanical soil reconstruction system on a surface coal mine operated by Peabody Energy. The proposed project would result in a side-by-side comparison of the system with the current best method used by Peabody Energy. Soil reconstruction rate and resulting soil physical properties would be intensively mopnitoried and compared during 2008. The ultimate goal of the project would be to establish the system as a superior method of soil reconstruction which can re-establish crop production potential in prime farmland and other agricultural soils.

Publications

  • Pitla, S.K., L.G. Wells and S.A. Shearer. 2007. Identifying soil compaction using an extended ring transducer and soil coulterometer. Amer. Soc. Agr. and Biol. Engineers paper no. 071005, St. Joseph, MI.
  • Bodapati. V.S. and L.G. Wells. 2007. Evaluation of a mechanical system for reconstructing soil without traffic compaction. Procs. of the 2007 Annual Meeting of the Amer. Soc. for Mining and Reclamation, Gillette, WY.


Progress 01/01/06 to 12/31/06

Outputs
A coulter impedometer was fabricated and tested in 2006. The impedometer consisted of a 32 in. diameter coulter mounted on a special transducer for measuring both vertical and horizontal soil resistance to the coulter. This coulter/transducer assembly was mounted on a framework so that a hydraulic cylinder pushed the coulter 4-14 in. into the soil. The hydraulic cylinder was made to oscillate between full extension and full retraction by a control circuit. The entire assembly was mounted on the three-point hitch of a conventional tractor, which supplied hydraulic power via remote connectors. The tractor was driven at a constant speed while the depth of coulter penetration was continuously varied between 4 and 14 in. Vertical resistance to coulter penetration was measured throughout a 1-acre plot between depths of 4 and 14 in. A soil coulter penetration index was computed as the vertical coulter resistance force divided by the coulter arc length in contact with the soil. These measurements were compared to 40 soil cone pentrometer measuremnts at 2-in. increments between 4 in. and 14 in. collected at 10 locations within the plot. Soil bulk density and water content were measured at the same locations using a dual probe gamma moisture-density guage. Pearson correlation coefficient (r) and coeficcicient of determination (rxr) between the coulter index and cone index were 0.716 and 0.51, respectively. This indicated that the coulter index may be an accurate and cost-effective method of assessing soil compaction in cropland. A mechanical system for reconstructing surface-mined cropland was modified to improve performance and capacity. The system consisted of a powered auger, 36 in. in diameter, mounted on a conventional bulldozer above a modified blade. Soil deposited on graded spoil is engaged by the system and displaced into an embankment up to 48 in. deep. A 2-arce site was partially excavated for use in evaluating system performance and determining productivity of the reconstructed soil. Preliminary testing indentified a design deficiency which was addressed by modifying the shape of the blade in order to improve soil displacement. Excessive rainfall at the site prevented further testing during 2006.

Impacts
Successful development of a mechanical system to reconstruct soil following severe disturbance will ensure reclamation of thousands of acres of agricultural lands that may be subjected to surface mining. Reliable and cost-effective determination and location of detrimental soil compaction in cropland is vital for application of remedial tillage. Combining such assessment with deep tillage implements capable of variable depth operation can minimize time and energy expenditures in restoring soil productivity.

Publications

  • No publications reported this period


Progress 01/01/05 to 12/31/05

Outputs
1. Design drawings have been completed for modification of a mechanical system for reconstructing severely disturbed soil. A 3 acre site has been identified at the University of Kentucky Coldstream research farm to be excavated to a depth of 4 ft and reconstructed using the system. Tests will be conducted during March-April 2006 to determine system capacity and to assess performance requirements. Replicated plots will be reconstructed whereby effects of mixing soil horizons and adding organic matter upon soil productivity will be evaluated. 2. Design drawings have been completed for fabrication of a mechanical system to measure soil compaction. The system will utilize a 32 in. diameter coulter mounted on a tool bar. A hyrdraulic cylinder will cycle repeatedly to vary depth of coulter penetration in soil between 4 and 12 in. A force gauge will continously measure both vertical and horizontal force acting on the coulter and a position transducer will measure depth. These measurements will be recorded electronically and indexed to GPS spatial coordinates. Operating the system in a field will thus result in replicated measurements of soil impedance versus depth. Experiments will be conducted during March 2006 whereby these measurements will be compared to standard soil cone pentetrometer and soil density measurements. 3. Sites will be identified in 2006 where adverse soil compaction is suspected. Assessement of soil compaction will occur early in 2007 and remedial precision deep tillage will be applied in 2007.

Impacts
Successful development of a mechanical system to reconstruct soil following severe disturbance will ensure reclamation of thousands of acres of agricultural lands that may be subjected to surface mining. Reliable and cost-effective determination and location of detrimental soil compaction in cropland is vital for application of remedial tillage. Combining such assessment with deep tillage implements capable of variable depth operation can minimize time and energy expenditures in restoring soil productivitiy.

Publications

  • No publications reported this period