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University of Nebraska - Lincoln
Department of Biological Systems Engineering: Dissertations and Theses
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- Agriculture (1)
- Ambient odor assessment methods (1)
- Annual ET (1)
- Bioenergy (1)
- Biofuel (1)
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- Carbon (1)
- Cellulosic (1)
- Climate Change (1)
- Climate change (1)
- Crop Residue (1)
- Cycle (1)
- Ethanol (1)
- Evapotranspiration (1)
- Fingerprinting (1)
- Gas (1)
- Greenhouse (1)
- Groundwater (1)
- Groundwater Storage (1)
- Landuse/landcover (1)
- Life (1)
- Mask scentometer (1)
- Nasal ranger (1)
- Odor (1)
- Odor intensity (1)
- Odor modeling (1)
- Precipitation (1)
- Seasonal ET (1)
- Soil (1)
- Soil Carbon (1)
- Surface energy (1)
Articles 1 - 5 of 5
Full-Text Articles in Engineering
Development And Assessment Of A Groundwater Sustainability Index In Climatically Diverse Groundwater Irrigated Regions In Nebraska, Maria A. Mulet Jalil
Development And Assessment Of A Groundwater Sustainability Index In Climatically Diverse Groundwater Irrigated Regions In Nebraska, Maria A. Mulet Jalil
Department of Biological Systems Engineering: Dissertations and Theses
The aim of this research was to evaluate the impact of regional change in ET on groundwater level changes and the assessment and development of a groundwater sustainability index for climatically diverse regions across Nebraska during 2000-2014. Irrigation in the selected regions is predominantly supplied by groundwater. The hypothesis is that groundwater use can become sustainable if the regional evapotranspiration (ET) is managed so that it equals the ET of vegetation that is native to the region. Site locations were Box Butte, Chase, Dundy, Holt LNNRD and York Counties and 3 ecosystems were evaluated: native vegetation, dryland and irrigated cropping …
Soil Organic Carbon Dynamics In Agriculture: Model Development And Application From Daily To Decadal Timescales, Matthew P. Pelton
Soil Organic Carbon Dynamics In Agriculture: Model Development And Application From Daily To Decadal Timescales, Matthew P. Pelton
Department of Biological Systems Engineering: Dissertations and Theses
Soil carbon (C) is the largest terrestrial C pool globally, containing more C than the atmosphere and biosphere. Soil organic carbon (SOC) is a source and sink of CO2 emissions to and from the atmosphere, thus influencing future climate change. Understanding SOC dynamics is also important for maintaining C stocks to sustain and improve crop yields. An existing model to estimate changes in SOC due to respiration was modified to operate in three computational platforms: MS Excel, MS Excel with Visual Basic for Applications, and supercomputing. This model was validated against CO2 flux data from a 9-year field …
Soil Greenhouse Gas Emissions In The Life Cycle Assessment Of Cellulosic Ethanol From Crop Residue, Xiao Xue Fang
Soil Greenhouse Gas Emissions In The Life Cycle Assessment Of Cellulosic Ethanol From Crop Residue, Xiao Xue Fang
Department of Biological Systems Engineering: Dissertations and Theses
Concerns about climate change and the increasing cost of fossil fuels have led to interest in the development of renewable biofuel pathways for reducing greenhouse gas (GHG) emissions. The use of corn residue as a potential source of biomass feedstock for cellulosic ethanol production has been favored as cost effective. Previous research has shown that crop residue removal can cause a loss of soil organic carbon (SOC), which potentially is a source of GHG emissions in the form of CO2. Using a life cycle assessment (LCA) approach, this study investigated the impact of corn residue removal on total …
Identifying Changes In Climatic Trends And The Fingerprints Of Landuse And Landcover Changes In The High Plains Of The Usa, Denis Mutiibwa
Identifying Changes In Climatic Trends And The Fingerprints Of Landuse And Landcover Changes In The High Plains Of The Usa, Denis Mutiibwa
Department of Biological Systems Engineering: Dissertations and Theses
Human activities such as conversion of natural ecosystem to croplands and urban-centers, deforestation and afforestation impact biophysical properties of land surface such as albedo, energy balance, and surface roughness. Alterations in these properties affect the heat and moisture exchanges between the land surface and atmospheric boundary layer. The objectives of this research were; (i) to quantitatively identify the High plains’ regional climate change in temperatures over the period 1895 to 2006, (ii) detect the signatures of anthropogenic forcing of LULC changes on the regional climate change of the High Plains, and (iii) examine the trends in evolving regional latent heat …
Development Of The Mask Scentometer, A Comparison Of Ambient Odor Assessment Methods, And Their Application In Ground Truthing Atmospheric Dispersion Models, Christopher G. Henry
Development Of The Mask Scentometer, A Comparison Of Ambient Odor Assessment Methods, And Their Application In Ground Truthing Atmospheric Dispersion Models, Christopher G. Henry
Department of Biological Systems Engineering: Dissertations and Theses
This dissertation is organized as four stand-alone papers. Paper No. 1 describes the development of the Mask Scentometer and reports dilution ratios measured during use by twelve different people. Dilution ratios at the Mask Scentometer’s five dilution-to-threshold (D/T) settings were found to be 0.35, 1, 2, 4.5 and 18. In Paper No.’s 2 and 4, ambient odor assessment methods were compared in both controlled laboratory conditions and in the field. Laboratory analysis of ambient air samples using dynamic triangular forced-choice olfactometry (DTFCO) did not correlate well with any of the ambient odor assessment methods. Average intensity-predicted D/T was roughly five …