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Impact Of Biochar Amendments On The Quality Of A Typical Midwestern Agricultural Soil, David A. Laird, Pierce Fleming, Dedrick D. Davis, Robert Horton, Baiqun Wang, Douglas L. Karlen Aug 2019

Impact Of Biochar Amendments On The Quality Of A Typical Midwestern Agricultural Soil, David A. Laird, Pierce Fleming, Dedrick D. Davis, Robert Horton, Baiqun Wang, Douglas L. Karlen

Douglas L Karlen

Biochar, a co-product of thermochemical conversion of lignocellulosic materials into advanced biofuels, may be used as a soil amendment to enhance the sustainability of biomass harvesting. We investigated the impact of biochar amendments (0, 5, 10, and 20 g-biochar kg− 1 soil) on the quality of a Clarion soil (Mesic Typic Hapludolls), collected (0–15 cm) in Boone County, Iowa. Repacked soil columns were incubated for 500 days at 25 °C and 80% relative humidity. On week 12, 5 g of dried and ground swine manure was incorporated into the upper 3 cm of soil for half of the columns. Once …


Future Prospects For Corn As A Biofuel Crop, Kenneth J. Moore, Douglas L. Karlen, Kendall R. Lamkey Aug 2019

Future Prospects For Corn As A Biofuel Crop, Kenneth J. Moore, Douglas L. Karlen, Kendall R. Lamkey

Douglas L Karlen

Ethanol production from corn grain has increased signifi cantly during the past ten years in the US. This increase was driven by government policy guided by the Renewable Fuel Standard (RFS) and embodied in the Volumetric Ethanol Excise Tax Credit and other legislation created to promote a biofuels industry. As corn grain ethanol production approaches the target set out in the RFS, the industry is looking to develop capacity for producing advanced biofuels, primarily from agricultural wastes and dedicated energy crops. The residues remaining following corn harvest have been identifi ed as a voluminous and readily available feedstock for advanced …


Biochar Impact On Nutrient Leaching From A Midwestern Agricultural Soil, David Laird, Pierce Flemming, Baiqun Wang, Robert Horton, Douglas Karlen Aug 2019

Biochar Impact On Nutrient Leaching From A Midwestern Agricultural Soil, David Laird, Pierce Flemming, Baiqun Wang, Robert Horton, Douglas Karlen

Douglas L Karlen

Application of biochar to highly weathered tropical soils has been shown to enhance soil quality and decrease leaching of nutrients. Little, however, is known about the effects of biochar applications on temperate region soils. Our objective was to quantify the impact of biochar on leaching of plant nutrients following application of swine manure to a typical Midwestern agricultural soil. Repacked soil columns containing 0, 5, 10, and 20 g-biochar kg− 1-soil, with and without 5 g kg− 1 of dried swine manure were leached weekly for 45 weeks. Measurements showed a significant decrease in the total amount of N, P, …


Crop Residues: The Rest Of The Story, Douglas L. Karlen, Rattan Lal, Ronald F. Follett, John M. Kimble, Jerry L. Hatfield, John A. Miranowski, Cynthia A. Cambardella, Andrew Manale, Robert P. Anex, Charles W. Rice Jun 2017

Crop Residues: The Rest Of The Story, Douglas L. Karlen, Rattan Lal, Ronald F. Follett, John M. Kimble, Jerry L. Hatfield, John A. Miranowski, Cynthia A. Cambardella, Andrew Manale, Robert P. Anex, Charles W. Rice

Douglas L Karlen

Synopsis In the February 15, 2009 issue of ES&T Strand and Benford argued that oceanic deposition of agricultural crop residues was a viable option for net carbon sequestration (43 [4], 1000−1007). In reviewing the calculations and bringing their experience to bear, Karlen et al. argue in this Viewpoint that crop residue oceanic permanent sequestration (CROPS) as envisioned by Strand and Benford will not work. They further propose alternative possibilities in agricultural methods to achieve a net decrease of CO2 emissions.


Fluid Fertilizer’S Role In Sustaining Soils Used For Bio-Fuels Production, John L. Kovar, Douglas Karlen Jun 2017

Fluid Fertilizer’S Role In Sustaining Soils Used For Bio-Fuels Production, John L. Kovar, Douglas Karlen

Douglas L Karlen

The short- and long-term effects on soil nutrient cycling, physical properties, and biological activity of striving for higher grain yields and removing crop residues for bio-fuels production must be understood to provide more quantitative crop and soil management guidelines. This study focuses on potassium (K) and sulfur (S) requirements of corn (Zea mays L.) grown for bioenergy feedstock production. Our objectives for 2008 were to: i) evaluate the performance of several S fertilizers, including liquid ammonium thiosulfate (12-0-0-26S), as S sources for corn grown in Iowa, and ii) establish a comprehensive tillage, nutrient management, crop residue removal, and cover crop …


Crop Residue Harvest Economics: An Iowa And North Dakota Case Study, David W. Archer, Douglas L. Karlen, Mark A. Liebig Dec 2015

Crop Residue Harvest Economics: An Iowa And North Dakota Case Study, David W. Archer, Douglas L. Karlen, Mark A. Liebig

Douglas L Karlen

Rigorous economic analyses are crucial for the successful launch of lignocellulosic bioenergy facilities in 2014 and beyond. Our objectives are to (1) introduce readers to a query tool developed to use data downloaded from the Agricultural Research Service (ARS) REAPnet for constructing enterprise budgets and (2) demonstrate the use of the query tool with REAPnet data from two field research sites (Ames, IA, and Mandan, ND) for evaluating short-term economic performance of various biofuel feedstock production strategies. Our results for both sites showed that short-term (<3 years) impacts on grain profitability were lower at lower average annual crop residue removal rates. However, it will be important to monitor longer term changes to see if grain profitability declines over time and if biomass harvest degrades soil resources. Analyses for Iowa showed short-term breakeven field-edge biomass prices of $26–$42Mg−1 among the most efficient strategies, while results for North Dakota showed breakeven prices …


Crop Residues, Douglas L. Karlen, David R. Huggins Dec 2015

Crop Residues, Douglas L. Karlen, David R. Huggins

Douglas L Karlen

Crop residues (e.g., corn stover and small grain straw) are sometimes excluded when discussing cellulosic energy crops per se, but because of the vast area upon which they are grown and their current role in the development of cellulosic energy systems, this chapter will review several important attributes of this “herbaceous” feedstock. Crop residues are potential feedstock sources for second-generation biofuel production. These materials, along with dedicated energy crops (e.g., switchgrass [Panicum virgatum L.], Miscanthus [Miscanthus × giganteus]), are considered to have greater potential for biofuel production than current first-generation feedstock (i.e., corn grain) [1–3]. Production of ethanol and other …


Fluid Fertilizer’S Role In Sustaining Soils Used For Bio-Energy Feedstock Production, John L. Kovar, Douglas L. Karlen Dec 2015

Fluid Fertilizer’S Role In Sustaining Soils Used For Bio-Energy Feedstock Production, John L. Kovar, Douglas L. Karlen

Douglas L Karlen

The use of corn (Zea mays L.) as a bio-energy feedstock has attracted the attention of many producers. Recently, the focus has shifted from grain-based to cellulose-based ethanol production. In addition to biological conversion of corn stover to ethanol, thermal conversion (pyrolysis) of stover is being explored. Regardless of post-harvest processing, the short- and long-term effects of both increasing grain yields and removing stover on soil nutrient cycling, physical properties, and biological activity must be understood to ensure that soil productivity and ecosystem services are maintained. Our objectives for 2010 were to evaluate: (i) the use of surface or …


Fluid Fertilizer’S Role In Sustaining Soils Used For Bio-Fuels Production, John L. Kovar, Douglas L. Karlen Dec 2015

Fluid Fertilizer’S Role In Sustaining Soils Used For Bio-Fuels Production, John L. Kovar, Douglas L. Karlen

Douglas L Karlen

Fast pyrolysis is optimized for production of bio-oil. Product yields are typically ~65% bio-oil, 20% biochar, 15% syngas.

Project Objective

To investigate N, P, K, and S dynamics in a comprehensive residue removal, tillage, and nutrient management study

Project Treatments

*Residue removal: 0, 50%, 90%

*Tillage: chisel plow, no-till

*Nutrient management: conventional (30K plants/A), high input (44K plants/A)

•Bio-char: 0, 4.32 tons/A, 8.25 tons/A

•Cover crops: annual, perennial

2009 Soil Test Levels

2009 Nutrient Management

Field Measurements

•Stand counts

•Whole-plant samples at V6

•Ear-leaf samples at mid-silk

•Grain yield and moisture

•Stover yield and moisture

•Grain and stover nutrient content


Nutrient Removal As A Function Of Corn Stover Cutting Height And Cob Harvest, Jane M. F. Johnson, Wally W. Wilhelm, Douglas L. Karlen, David W. Archer, Brian J. Wienhold, David T. Lightle, David Laird, John Baker, Tyson E. Ochsner, Jeff M. Novak, Ardell D. Halvorson, Francisco Arriaga, Nancy Barbour Dec 2015

Nutrient Removal As A Function Of Corn Stover Cutting Height And Cob Harvest, Jane M. F. Johnson, Wally W. Wilhelm, Douglas L. Karlen, David W. Archer, Brian J. Wienhold, David T. Lightle, David Laird, John Baker, Tyson E. Ochsner, Jeff M. Novak, Ardell D. Halvorson, Francisco Arriaga, Nancy Barbour

Douglas L Karlen

One-pass harvest equipment has been developed to collect corn (Zea mays L.) grain, stover, and cobs that can be used as bioenergy feedstock. Nutrients removed in these feedstocks have soil fertility implication and affect feedstock quality. The study objectives were to quantify nutrient concentrations and potential removal as a function of cutting height, plant organ, and physiological stage. Plant samples were collected in 10-cm increments at seven diverse geographic locations at two maturities and analyzed for multiple elements. At grain harvest, nutrient concentration averaged 5.5 gN kg−1, 0.5 gP kg−1, and 6.2 gK kg−1 …


Corn Stover Nutrient Removal Estimates For Central Iowa, Usa, Douglas Karlen, John Kovar, Stuart J. Birrell Dec 2015

Corn Stover Nutrient Removal Estimates For Central Iowa, Usa, Douglas Karlen, John Kovar, Stuart J. Birrell

Douglas L Karlen

One of the most frequent producer-asked questions to those persons striving to secure sustainable corn (Zea mays L.) stover feedstock supplies for Iowa’s new bioenergy conversion or other bio-product facilities is “what quantity of nutrients will be removed if I harvest my stover?” Our objective is to summarize six years of field research from central Iowa, U.S.A. where more than 600, 1.5 m2 samples were collected by hand and divided into four plant fractions: vegetative material from the ear shank upward (top), vegetative material from approximately 10 cm above the soil surface to just below the ear (bottom), cobs, and …