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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

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

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

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

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

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 …

Comparative Sorption Of Pb And Cd By Biochars And Its Implication For Metal Immobilization In Soils, Jin Hee Park, Girish Choppala, Seul Lee, Nanthi Bolan, Jae Chung, Mansour Edraki

Dr Girish Choppala

Biochar has great potential as a soil amendment to immobilize heavy metals, thereby reducing their bioavailability. In this study, biochars derived from chicken manure and green waste were compared with commercial activated carbon (AC) and laboratory produced black carbon (BC) for the sorption of Pb and Cd. Sorption kinetics and equilibrium sorption isotherms for Pb and Cd were obtained for the char materials and the data were fitted to kinetic and sorption isotherm models.. Chicken manure-derived biochar (CM) showed the highest sorption capacity for both Pb and Cd, and the Pb sorption by biochars was higher than the Cd sorption …

Phytocapping: An Alternative Technology For The Sustainable Management Of Landfill Sites, Dane Lamb, Kartik Venkatraman, Nanthi Bolan, Nanjappa Ashwath, Girish Choppala, Ravi Naidu

Dr Girish Choppala

Landfill remains the predominant means of waste disposal throughout the globe. Numerous landfills exist in developed and underdeveloped countries, engineered with contrasting degrees of effectiveness. Modern landfill closure in developed countries involves the conventional capping of waste with materials such as compacted clay or geosynthetic clay liners, typically overlain with other soil materials. Conventional capping technologies are now accepted to be increasingly ineffective in reducing percolation into waste. Cost-effective alternative systems are of increasing interest, including the use of plants to control and limit water entry into waste, otherwise known as “Phytocapping”. Phytocapping reduces percolation through three main mechanisms: (a) …

Chemodynamics Of Chromium Reduction In Soils: Implications To Bioavailability, Girish Choppala, Nanthi Bolan, Belaji Seshadri

Dr Girish Choppala

Chromium toxicity in soils can be mitigated by reduction of Cr(VI) to Cr(III) which is influenced by the presence of free Cr(VI) species in soil solution, and the supply of protons and electrons. In this study, the effects of Cr(VI) adsorption (i.e. availability of free Cr(VI) species in soil solution), soil pH (i.e. supply of protons) and three electron donor carbon sources [black carbon (BC), chicken manure biochar (CMB) and cow manure (CM)] on the reduction of Cr(VI) to Cr(III) in soils were investigated. The results indicated that the rate of Cr(VI) reduction decreased with an increase in Cr(VI) adsorption …

Concomitant Reduction And Immobilization Of Chromium In Relation To Its Bioavailability In Soils, Girish Choppala, Nanthi Bolan, Anitha Kunhikrishnan, William Skinner, Balaji Seshadri

Dr Girish Choppala

In this study, two carbon materials [chicken manure biochar (CMB) and black carbon (BC)] were investigated for their effects on the reduction of hexavalent chromium [Cr(VI)] in two spiked [600 mg Cr(VI) kg−1] and one tannery waste contaminated [454 mg Cr(VI) kg−1] soils. In spiked soils, both the rate and the maximum extent of reduction of Cr(VI) to trivalent Cr [Cr(III)] were higher in the sandy loam than clay soil, which is attributed to the difference in the extent of Cr(VI) adsorption between the soils. The highest rate of Cr(VI) reduction was observed in BC-amended sandy loam soil, where it …

Biochar Reduces The Bioavailability And Phytotoxicity Of Heavy Metals, Jin Hee Park, Girish Choppala, Nanthi Bolan, Jae Chung, Thammared Chuasavathi

Dr Girish Choppala

Background and aims

Biochar has attracted research interest due to its ability to increase the soil carbon pool and improve crop productivity. The objective of this study was to evaluate the metal immobilizing impact of chicken manure- and green waste-derived biochars, and their effectiveness in promoting plant growth.

Methods

The immobilization and phytoavailability of Cd, Cu and Pb was examined using naturally contaminated shooting range and spiked soils. Biochar samples prepared from chicken manure and green waste were used as soil amendments.

Results

Application of biochar significantly reduced NH₄NO₃ extractable Cd, Cu and Pb concentrations of soils, …

Stabilization Of Carbon In Composts And Biochars In Relation To Carbon Sequestration And Soil Fertility, Nanthi Bolan, Anitha Kunhikrishnan, Girish Choppala, R Thangarajan, J Chung

Dr Girish Choppala

There have been increasing interests in the conversion of organic residues into biochars in order to reduce the rate of decomposition, thereby enhancing carbon (C) sequestration in soils. However energy is required to initiate the pyrolysis process during biochar production which can also lead to the release of greenhouse gasses. Alternative methods can be used to stabilize C in composts and other organic residues without impacting their quality. The objectives of this study include: (i) to compare the rate of decomposition among various organic amendments and (ii) to examine the effect of clay materials on the stabilization of C in …

The Influence Of Biochar And Black Carbon On Reduction And Bioavailability Of Chromate In Soils, Girish Choppala, Nanthi Bolan, M Megharaj, Z Chen, Ravi Naidu

Dr Girish Choppala

The widespread use of chromium (Cr) has a deleterious impact on the environment. A number of pathways, both biotic and abiotic in character, determine the fate and speciation of Cr in soils. Chromium exists in two predominant species in the environment: trivalent [(Cr(III)] and hexavalent [Cr(VI)]. Of these two forms, Cr(III) is nontoxic and is strongly bound to soil particles, whereas Cr(VI) is more toxic and soluble and readily leaches into groundwater. The toxicity of Cr(VI) can be mitigated by reducing it to Cr(III) species. The objective of this study was to examine the effect of organic carbon sources on …