199,779 research outputs found
Sustainability of Corn Stover Harvest for Biomass
No full textOff-farm demand for crop residues is expected to grow as bioenergy policies become effective. Demand for residues will provide farmers with an additional source of revenue but it may also trigger losses in soil organic carbon and increases in fertilizer application. This study develops a dynamic economic model of stover harvest that permits conceptualization and quantification of these potential tradeoffs. We parameterize our model based on publicly available studies of soil biophysical relationships in the Corn Belt. Under these parameter values and 2010 corn and fertilizer prices harvesting stover is not economically convenient at prices below $53 per dry ton of stover. Results suggest that the rate of stover harvest may be quite sensitive and negatively linked to corn prices, which means that policies favoring the use of stover for biomass may be overridden by further increases in corn price. The negative link between stover harvest and corn prices, while somewhat counterintuitive, is driven by the fact that removal of stover reduces future grain yield (through reductions in soil organic carbon). Results also seem to indicate that, under plausible parameter values, profit maximizing farmers would increase stover supply in response to increases in stover price. However increases in supply are, according to our simulations, associated with (potentially significant) reductions in soil organic carbon (and hence carbon emissions as these are positively linked) and increases in nitrogen application (and potential runoffs). This result suggests that concerns about adverse environmental implications of harvesting stover may be justified, and more precise quantification of environmental tradeoffs should be pursued by future research.stover supply, biomass, soil productivity, soil organic carbon, nitrogen, Environmental Economics and Policy, Farm Management, Land Economics/Use, Resource /Energy Economics and Policy, C61, Q12, Q24, Q42, Q53,
A Corn Stover Supply Logistics System
No full textPublished in Applied Engineering in Agriculture, Vol. 26(3): 455‐461, 2010. American Society of Agricultural and Biological EngineersCorn stover, Economics, GHG emission, Logistics, Roll press compaction, Tub grinding, Agribusiness, Crop Production/Industries,
The Viability of Harvesting Corn Cobs and Stover for Biofuel Production in North Dakota
No full textThis study examines the impact of stochastic harvest field time, corn cob and stover harvest technologies, increases in farm size, and alternative tillage practices on profit maximizing potential of corn cob and stover collection in North Dakota. Using three mathematical programming models, we analyze farmers’ harvest activities under 1) corn grain only harvest option, 2) simultaneous corn grain and cob harvest(one-pass) option 3) separate corn grain and stover harvest (two-pass) option. Under the first corn grain only option, farmers are able to complete harvesting corn grain and achieve maximum net income in a fairly short amount of time with existing combine technology. However, under the simultaneous corn grain and cob one-pass harvest option, our findings indicate that farmers generate lower net income as compared to the net income of corn grain only harvest option. This is due to the slowdown in combine harvest capacity as a consequence of attaching cob harvester to the back of combine. Under the third option of a two-pass harvest system, time allocation is the main challenge and our evidence shows that with limited harvest field time available, farmers find it optimal to allocate most of their time harvesting grain, and then proceed to bale stover if time permits at the end of harvest season. As farm size increases, farmers are especially challenged in finding time to harvest both corn grain and cobs/stover. We show that a small decrease in corn yield due to changes in tillage practice can result in a large decline in the net profit of harvesting corn grain and cobs/stover.Cob, Stover, harvest field time, optimization, farm size, tillage, Crop Production/Industries, Production Economics,
Ethanol from Biomass: Economic and Environmental Potential of Converting Corn Stover and Hardwood Forest Residue in Minnesota
No full textResearch was undertaken to determine the economic feasibility and environmental impact of harvesting corn stover and hardwood forest residue in Minnesota and surrounding states for conversion to fuel ethanol at facilities located in Minnesota. It was estimated that only 7 of the total 41 million dry tons of corn stover produced and 3 of the 6.5 million dry tons of hardwood residue produced in the study region would likely be harvested each year. From these quantities, it would be physically feasible to produce about 874 million gallons of ethanol annually. It was estimated that 200 million gallons could be harvested at a delivered feedstock cost below 0.16 per-gallon higher than the upper-bound cost for corn-grain ethanol. Furthermore, this work indicates that large-scale substitution of petroleum gasoline with biomass-derived ethanol would have huge impacts with respect to reducing greenhouse gas emissions, although SOx emissions would increase.Resource /Energy Economics and Policy,
Economics of Sourcing Cellulosic Feedstock for Energy Production
No full textThis study investigates the economics of supplying wheat straw and corn stover within 100 mile radius of a potential new biorefinery in southeast North Dakota. In particular, straw and stover total delivery costs, potential straw and stover supply sites and least cost transportation routes are identified using a linear programming transport model and a GIS (Geographic Information Systems) mapping system. We show that USDA/NRCS (Natural Resources Conservation Service) future crop residue removal rate policies will be important for determining whether it is economically viable to harvest crop residues as potential feedstock for energy generation. Increase in residue removal rates narrow the size of residue supply areas and consequently result in lowering total transportation costs. There is an economic tradeoff between residue collection density and distance from the biorefinery. Most wheat residues are highly concentrated in the north, some distance from the biorefinery. Relying solely on wheat straw for supply needs require longer transportation distances which increases total cost. Using a combination of wheat and corn residues lowers total transportation costs. Since most wheat/corn residues are densely concentrated in north/south, regional highways would likely be the routes used often to transport the residues, as compared to interstate highways. Increased traffic volumes due to the hauling of crop residues would require additional investment in improving road conditions.Wheat Straw, Corn Stover, Density, Transportation Cost, GIS, Community/Rural/Urban Development, Crop Production/Industries,
Sorghum stover removal and fertilizer nitrogen effects on sorghum yields and nutrient cycling
No full textTypescript (photocopy).A four year field study was conducted to evaluate the effects of sorghum stover removal and fertilizer N on yields of four sorghum genotypes, soil properties, and nutrient cycling in a conventional tillage, continuous sorghum cropping system. Applications of 112 kg N ha����� were generally sufficient for maximum yields, fertilizer N uptake efficiency and, the greatest percentage partitioning of N, P and K uptake into grain. In some years stovers apparently acted as sinks, immobilizing and/or denitrifying N. Stover parts such as stalks and lower stover components contained high amounts of nonstructural and structural carbohydrates and had a high C:N ratio, immobilizing applied N for 9 months in a greenhouse study. The noted increase in yield variability during the latter study years, the reduced ability of fertilizer N to affect yields, and stover's positive effects on N and P cycling may have been due to cumulative adverse effects of stover removal on the soil environment. Complete stover removal reduced soil available P and K levels, and disrupted the soil organic matter (SOM) equilibrium, resulting in increased SOM decomposition and a net release of nutrients. Returning upper sorghum stover portions to fields would cycle a relatively high percentage of stover N and P, while the remaining lower two-thirds, high in carbohydrates, could be harvested for energy conversion. Interactions of sorghum genotypes, fertilizer N and stover return effects on long-term soil productivity must be delineated to determine if stover removal can become an environmentally sound and sustainable production strategy
Probing the nature of AFEX-pretreated corn stover derived decomposition products that inhibit cellulase activity
No full textSequential fractionation of AFEX-pretreated corn stover extracts was carried out using ultra-centrifugation, ultra-filtration, and solid phase extraction to isolate various classes of pretreatment products to evaluate their inhibitory effect on cellulases. Ultra-centrifugation removed dark brown precipitates that caused no appreciable enzyme inhibition. Ultra-filtration of ultra-centrifuged AFEX-pretreated corn stover extractives using a 10 kDa molecular weight cutoff (MWCO) membrane removed additional high molecular weight components that accounted for 24–28% of the total observed enzyme inhibition while a 3 kDa MWCO membrane removed 60–65%, suggesting significant inhibition is caused by oligomeric materials. Solid phase extraction (SPE) of AFEX-pretreated corn stover extractives after ultra-centrifugation removed 34–43% of the inhibition; ultra-filtration with a 5 kDa membrane removed 44–56% of the inhibition and when this ultra-filtrate was subjected to SPE a total of 69–70% of the inhibition were removed. Mass spectrometry found several phenolic compounds among the hydrophobic inhibition removed by SPE adsorption.Published version: Humpula, James F., Uppugundla, Nirmal, Vismeh, Ramin, Sousa, Leonardo, Chundawat, Shishir P. S., Jones, A. Daniel, Balan, Venkatesh, Dale, Bruce E. & Cheh, Albert M. (2014). Probing the nature of AFEX-retreated corn stover derived decomposition products that inhibit cellulase activity. Bioresource Technology 152, 38-45. http://dx.doi.org/10.1016/j.biortech.2013.10.08
Stover and Sellers Families, Lydia Stover Haynie, mother of Leonard M. Haynie
No full textBlack and white photograph of Lydia Stover Haynie, mother of Leonard M. Haynie
Stover and Sellers Families, Jasper Stover and his wife, Palestine McDaniel Stover; Grandparents of Leonard M. Haynie, lawyer in Alamosa, Colorado.
No full textBlack and white photograph of Jasper Stover and his wife, Palestine McDaniel Stover. Grandparents of Leonard M. Haynie, a lawyer in Alamosa, Colorado
A note on prediction of maize stover quality by near-infrared reflectance spectroscopy (NIRS) technique
No full textNear-infrared reflectance spectroscopy (NIRS) technique was investigated as a means of
predicting quality parameters in semi-exotic maize stover. These parameters included neutral
detergent fibre (NDF) and in vitro dry matter (DM) digestibility. Samples of semi-exotic maize stover
were formed by crossing the exotic material Across 8443 La Posta with inbred Mo 17.Postprint (published version
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