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Full-Text Articles in Engineering

Restoring Lake Urmia: Moving Beyond A Uniform Lake Level (2-Page Summary), Somayeh Sima, Dory Rosenberg, Wayne A. Wurtsbaugh, Sarah E. Null, Karin M. Kettenring Jul 2020

Restoring Lake Urmia: Moving Beyond A Uniform Lake Level (2-Page Summary), Somayeh Sima, Dory Rosenberg, Wayne A. Wurtsbaugh, Sarah E. Null, Karin M. Kettenring

Watershed Sciences Faculty Publications

More than 5 million people live near Lake Urmia in northwestern Iran, one of the world's largest hypersaline lakes. Over the past two decades, the lake has lost 95% of its volume, lake level has dropped more than 7 m, and lake restoration has gained widespread interest. The government seeks a uniform "ecological" target lake level of 1274.1 m above sea level to lower salinity below 240 gL-1 and recover brine shrimp (Artemia spp.) and flamingos (Phoenicopterus roseus).

We have synthesized over 40 years of available data, defined 8 ecosystem services for human health, water quality, ecology, recreation, and …


Implications Of Soil And Canopy Temperature Uncertainty In The Estimation Of Surface Energy Fluxes Using Tseb2t And High-Resolution Imagery In Commercial Vineyards, Ayman Nassar, Alfonso F. Torres-Rua, William Kustas, Héctor Nieto, Mac Mckee, Lawrence Hipps, Joseph Alfieri, John H. Prueger, Maria Mar Alsina, Lynn Mckee, Calvin Coopmans, Luis Sanchez, Nick Dokoozlian May 2020

Implications Of Soil And Canopy Temperature Uncertainty In The Estimation Of Surface Energy Fluxes Using Tseb2t And High-Resolution Imagery In Commercial Vineyards, Ayman Nassar, Alfonso F. Torres-Rua, William Kustas, Héctor Nieto, Mac Mckee, Lawrence Hipps, Joseph Alfieri, John H. Prueger, Maria Mar Alsina, Lynn Mckee, Calvin Coopmans, Luis Sanchez, Nick Dokoozlian

Civil and Environmental Engineering Faculty Publications

Estimation of surface energy fluxes using thermal remote sensing–based energy balance models (e.g., TSEB2T) involves the use of local micrometeorological input data of air temperature, wind speed, and incoming solar radiation, as well as vegetation cover and accurate land surface temperature (LST). The physically based Two-source Energy Balance with a Dual Temperature (TSEB2T) model separates soil and canopy temperature (Ts and Tc) to estimate surface energy fluxes including Rn, H, LE, and G. The estimation of Ts and Tc components for the TSEB2T model relies on the linear relationship between the composite land surface temperature and a vegetation index, namely …


To What Extent Does The Eddy Covariance Footprint Cutoff Influence The Estimation Of Surface Energy Fluxes Using Two Source Energy Balance Model And High-Resolution Imagery In Commercial Vineyards?, Ayman Nassar, Alfonso F. Torres-Rua, William Kustas, Héctor Nieto, Mac Mckee, Lawrence Hipps, Joseph Alfieri, John H. Prueger, Maria Mar Alsina, Lynn Mckee, Calvin Coopmans, Louis Sanchez, Nick Dokoozlian May 2020

To What Extent Does The Eddy Covariance Footprint Cutoff Influence The Estimation Of Surface Energy Fluxes Using Two Source Energy Balance Model And High-Resolution Imagery In Commercial Vineyards?, Ayman Nassar, Alfonso F. Torres-Rua, William Kustas, Héctor Nieto, Mac Mckee, Lawrence Hipps, Joseph Alfieri, John H. Prueger, Maria Mar Alsina, Lynn Mckee, Calvin Coopmans, Louis Sanchez, Nick Dokoozlian

Civil and Environmental Engineering Faculty Publications

Validation of surface energy fluxes from remote sensing sources is performed using instantaneous field measurements obtained from eddy covariance (EC) instrumentation. An eddy covariance measurement is characterized by a footprint function / weighted area function that describes the mathematical relationship between the spatial distribution of surface flux sources and their corresponding magnitude. The orientation and size of each flux footprint / source area depends on the micro-meteorological conditions at the site as measured by the EC towers, including turbulence fluxes, friction velocity (ustar), and wind speed, all of which influence the dimensions and orientation of the footprint. The …


Estimation Of Evapotranspiration And Energy Fluxes Using A Deep-Learning-Based High-Resolution Emissivity Model And The Two-Source Energy Balance Model With Suas Information, Alfonso F. Torres-Rua, Andres Ticlavilca, Mahyar Aboutalebi, Héctor Nieto, Maria Mar Alsina, Alex White, John H. Prueger, Joseph Alfieri, Lawrence Hipps, Lynn Mckee, William Kustas, Calvin Coopmans, Nick Dokoozlian May 2020

Estimation Of Evapotranspiration And Energy Fluxes Using A Deep-Learning-Based High-Resolution Emissivity Model And The Two-Source Energy Balance Model With Suas Information, Alfonso F. Torres-Rua, Andres Ticlavilca, Mahyar Aboutalebi, Héctor Nieto, Maria Mar Alsina, Alex White, John H. Prueger, Joseph Alfieri, Lawrence Hipps, Lynn Mckee, William Kustas, Calvin Coopmans, Nick Dokoozlian

Civil and Environmental Engineering Faculty Publications

Surface temperature is necessary for the estimation of energy fluxes and evapotranspiration from satellites and airborne data sources. For example, the Two-Source Energy Balance (TSEB) model uses thermal information to quantify canopy and soil temperatures as well as their respective energy balance components. While surface (also called kinematic) temperature is desirable for energy balance analysis, obtaining this temperature is not straightforward due to a lack of spatially estimated narrowband (sensor-specific) and broadband emissivities of vegetation and soil, further complicated by spectral characteristics of the UAV thermal camera. This study presents an effort to spatially model narrowband and broadband emissivities for …


Ranchers Adapting To Climate Variability In The Upper Colorado River Basin, Utah, Hadia Akbar May 2020

Ranchers Adapting To Climate Variability In The Upper Colorado River Basin, Utah, Hadia Akbar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Changes in climate influence agricultural production. This study looks at the impacts of climate variability in the Utah regions of the Upper Colorado River Basin by combining regression techniques with interview data to explore how climate variability affects agricultural production and how the farmers are adapting their practices to these changes. The results show that climate does not have any significant impact on cattle and hay production in the study area on a decadal scale. However, on an annual basis temperature seems to have more impact than precipitation. Among non-climatic variables, commodity prices and their regulations by the government are …


Estimation Of Surface Thermal Emissivity In A Vineyard For Uav Microbolometer Thermal Cameras Using Nasa Hytes Hyperspectral Thermal, And Landsat And Aggieair Optical Data, Alfonso F. Torres-Rua, Mahyar Aboutalebi, Timothy Wright, Ayman Nassar, Pierre Guillevic, Lawrence Hipps, Feng Gao, Kevin Jim, Maria Mar Alsina, Calvin Coopmans, Mac Mckee, William Kustas May 2019

Estimation Of Surface Thermal Emissivity In A Vineyard For Uav Microbolometer Thermal Cameras Using Nasa Hytes Hyperspectral Thermal, And Landsat And Aggieair Optical Data, Alfonso F. Torres-Rua, Mahyar Aboutalebi, Timothy Wright, Ayman Nassar, Pierre Guillevic, Lawrence Hipps, Feng Gao, Kevin Jim, Maria Mar Alsina, Calvin Coopmans, Mac Mckee, William Kustas

AggieAir Publications

Microbolometer thermal cameras in UAVs and manned aircraft allow for the acquisition of highresolution temperature data, which, along with optical reflectance, contributes to monitoring and modeling of agricultural and natural environments. Furthermore, these temperature measurements have facilitated the development of advanced models of crop water stress and evapotranspiration in precision agriculture and heat fluxes exchanges in small river streams and corridors. Microbolometer cameras capture thermal information at blackbody or radiometric settings (narrowband emissivity equates to unity). While it is customary that the modeler uses assumed emissivity values (e.g. 0.99– 0.96 for agricultural and environmental settings); some applications (e.g. Vegetation Health …


Validation Of Digital Surface Models (Dsms) Retrieved From Unmanned Aerial Vehicle (Uav) Point Clouds Using Geometrical Information From Shadows, Mahyar Aboutalebi, Alfonso F. Torres-Rua, Mac Mckee, William Kustas, Héctor Nieto, Calvin Coopmans May 2019

Validation Of Digital Surface Models (Dsms) Retrieved From Unmanned Aerial Vehicle (Uav) Point Clouds Using Geometrical Information From Shadows, Mahyar Aboutalebi, Alfonso F. Torres-Rua, Mac Mckee, William Kustas, Héctor Nieto, Calvin Coopmans

AggieAir Publications

Theoretically, the appearance of shadows in aerial imagery is not desirable for researchers because it leads to errors in object classification and bias in the calculation of indices. In contrast, shadows contain useful geometrical information about the objects blocking the light. Several studies have focused on estimation of building heights in urban areas using the length of shadows. This type of information can be used to predict the population of a region, water demand, etc., in urban areas. With the emergence of unmanned aerial vehicles (UAVs) and the availability of high- to super-high-resolution imagery, the important questions relating to shadows …


Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith Nov 2018

Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith

Civil and Environmental Engineering Faculty Publications

The goals of the original proposed project remain the same, that is, to test the hypothesis that Managed Aquifer Recharge (MAR) for stormwater harvesting is a technically feasible, socially and environmentally acceptable, economically viable, and legally feasible option for developing new water supplies for arid Western urban ecosystems experiencing increasing population, and climate change pressures on existing water resources. The project is being carried out via three distinct but integrated components that include: 1) Monitoring of existing distributed MAR harvesting schemes involving a growing number of demonstration Green Infrastructure (GI) test sites; 2) Integrated stormwater/vadose zone/groundwater/ ecosystem services modeling; and …


Implications Of Sensor Inconsistencies And Remote Sensing Error In The Use Of Small Unmanned Aerial Systems For Generation Of Information Products For Agricultural Management, Mac Mckee, Ayman Nassar, Alfonso F. Torres-Rua, Mahyar Aboutalebi, William Kustas May 2018

Implications Of Sensor Inconsistencies And Remote Sensing Error In The Use Of Small Unmanned Aerial Systems For Generation Of Information Products For Agricultural Management, Mac Mckee, Ayman Nassar, Alfonso F. Torres-Rua, Mahyar Aboutalebi, William Kustas

AggieAir Publications

Small, unmanned aerial systems (sUAS) for remote sensing represent a relatively new and growing technology to support decisions for agricultural operations. The size and power limitations of these systems present challenges for the weight, size, and capability of the sensors that can be carried, as well as the geographical coverage that is possible. These factors, together with a lack of standards for sensor technology, its deployment, and data analysis, lead to uncertainties in data quality that can be difficult to detect or characterize. These, in turn, limit comparability between data from different sources and, more importantly, imply limits on the …


Providing Professional Development To Educational Professionals For Unmanned Aerial Vehicles (Uavs) In Agriculture., Ashley Cromer, Tyson Sorensen, Kelsey Hall May 2018

Providing Professional Development To Educational Professionals For Unmanned Aerial Vehicles (Uavs) In Agriculture., Ashley Cromer, Tyson Sorensen, Kelsey Hall

Applied Sciences, Technology, and Education Student Research

Unmanned aerial vehicles (UAVs), also called drones, have been used commercially since the early 1980s. Today however, practical application for UAVs are expanding faster than ever in a variety of industries. UAV technology has given the agriculture industry the possibility of a technological makeover. Specifically, UAVs give the opportunity for improved crop supervision, soil and field analyses, and the ability to more closely and timely monitor crops (Mazur & Wisniewski, 2016). In order to keep up with increasing demands, agriculture has to utilize every technology available to the industry. Based on a global report published by PricewaterhouseCoopers (PWC), the market …


Measurement Of Agriculture-Related Air Pollutant Emissions Using Point And Remote Sensors, Kori D. Moore Dec 2017

Measurement Of Agriculture-Related Air Pollutant Emissions Using Point And Remote Sensors, Kori D. Moore

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Measuring air pollution emissions from agricultural activities is usually difficult because of their large area and variability. Traditional air quality sensors, called point samplers, measure conditions in one location, which may not adequately measure a plume. Remote sensors, instruments that measure pollution along a line rather than at a single point, are better able to measure conditions around large areas. This dissertation reports on four agricultural air emissions studies that used both point and remote sensors for comparison. The methods used to calculate the emissions are based on previous work and are further developed in these studies. In particular, an …


Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith Nov 2017

Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith

Civil and Environmental Engineering Faculty Publications

The aims of the original proposed project remain the same, that is, to test the hypothesis that Managed Aquifer Recharge (MAR) for stormwater harvesting is a technically feasible, socially and environmentally acceptable, economically viable, and legally feasible option for developing new water supplies for arid Western urban ecosystems experiencing increasing population, and climate change pressures on existing water resources. The project is being carried out via three distinct but integrated components that include: 1) Monitoring of existing distributed MAR harvesting schemes involving a growing number of demonstration Green Infrastructure (GI) test sites; 2) Integrated stormwater/vadose zone/groundwater/ ecosystem services modeling; and …


Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith Nov 2016

Ncer Assistance Agreement Annual Progress Report For Grant #83582401 - Assessment Of Stormwater Harvesting Via Manage Aquifer Recharge (Mar) To Develop New Water Supplies In The Arid West: The Salt Lake Valley Example, Ryan Dupont, Joan E. Mclean, Richard C. Peralta, Sarah E. Null, Douglas B. Jackson-Smith

Civil and Environmental Engineering Faculty Publications

The aims of the original proposed project remain the same, that is, to test the hypothesis that Managed Aquifer Recharge (MAR) for stormwater harvesting is a technically feasible, socially and environmentally acceptable, economically viable, and permittable option for developing new water supplies for arid Western urban ecosystems experiencing increasing population, and climate change pressures on existing water resources. The project is being carried out via three distinct but integrated components that include: 1) Monitoring of existing distributed Managed Aquifer Recharge (MAR) harvesting schemes involving a growing number of demonstration Green Infrastructure (GI) test sites; 2) Integrated stormwater/vadose zone/groundwater/ ecosystem services …


Systems Modeling And Economic Analysis Of Photovoltaic (Pv) Powered Water Pumping Brackish Water Desalination For Agriculture, Michael A. Jones May 2015

Systems Modeling And Economic Analysis Of Photovoltaic (Pv) Powered Water Pumping Brackish Water Desalination For Agriculture, Michael A. Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objective of this study was to determine the economic viability of solar powered water pumping and desalination systems for agriculture. Growing global demand for agricultural production has put increased pressure on limited freshwater resources in various locations around the word. Many areas have low quality groundwater resources that have not been utilized for agriculture due to limited availability to electricity, high operational costs of diesel generators and the economics associated with water pumping and processing. Reverse osmosis is a desalination technology that removes salts and other minerals from low-quality water, making it fit for drinking or irrigation. Reduced costs …


High Resolution Multi-Spectral Imagery And Learning Machines In Precision Irrigation Water Management, Leila Hassan-Esfahani May 2015

High Resolution Multi-Spectral Imagery And Learning Machines In Precision Irrigation Water Management, Leila Hassan-Esfahani

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The goals of preserving scarce water resources, cultivating more lands, and saving on irrigation water bills have directed the attention of water resources managers toward the concepts of precision agriculture and, in particular, to precision irrigation. The purpose of precision irrigation is to increase irrigation efficiency to avoid crop water stress, avoid yield reduction due to under-irrigation and leaching of nutrients, runoff, and reduce soil erosion due to over-irrigation. In this study, irrigation efficiency has been defined in terms of irrigation uniformity and the response of the crop to irrigation. Crop water demand, soil moisture, evapotranspiration rate, and potential water …


Estimation Of Field Alfalfa Evapotranspiration In A Windy, Arid Environment, J. Burdette Barker May 2011

Estimation Of Field Alfalfa Evapotranspiration In A Windy, Arid Environment, J. Burdette Barker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Evapotranspiration (ET) of center pivot irrigated alfalfa was studied in the windy, arid, Curlew Valley, Northern Box Elder County, Utah, during the summers of 2009 and 2010. ET was estimated using eddy covariance (EC) and surface renewal (SR) techniques. ET estimates from the EC and SR analyses were compared with estimates using ASCE Standardized Reference ET Equation, with both dual and mean crop coefficients.

EC energy balance closure was 0.80, on average, in 2009 and 0.76 in 2010. The SR weighting parameter (α) was calculated through linear regression of EC and SR sensible heat flux estimates. Alpha was found to …


An Autonomous Unmanned Aerial Vehicle-Based Imagery System Development And Remote Sensing Images Classification For Agricultural Applications, Yiding Han Dec 2009

An Autonomous Unmanned Aerial Vehicle-Based Imagery System Development And Remote Sensing Images Classification For Agricultural Applications, Yiding Han

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This work concentrates on the topic of remote sensing using a multispectral imag-ing system for water management and agriculture applications. The platform, which is alight-weight inexpensive runway-free unmanned aerial vehicle (UAV), namely, AggieAir, ispresented initially. A major portion of this work focuses on the development of a light-weight multispectral imager payload for the AggieAir platform, called GhostFoto. Theimager is band-recongurable, covering both visual red, green, and blue (RGB) and nearinfrared (NIR) spectrum, and interfaced with UAV on-board computer. The developmentof the image processing techniques, which are based on the collected multispectral aerialimages, is also presented in this work. One application …


Evaluation Of Arrayed-Field Concentration Measurements And U. S. Epa-Regulatory Models For The Determination Of Mixed-Source Particulate Matter Emissions, Derek Jones Dec 2008

Evaluation Of Arrayed-Field Concentration Measurements And U. S. Epa-Regulatory Models For The Determination Of Mixed-Source Particulate Matter Emissions, Derek Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With the continued population growth and the blurring of the urban and rural interface, air quality impacts associated with agricultural particle-producing processes are becoming increasingly important. There is a lack of emission rate data from these source types and no prescribed measurement technique available to the agricultural and regulatory communities. One technique that has shown promise is combining field measurements with inverse modeling. This approach was used herein to examine particulate emissions from an almond harvesting operation, a cotton ginning facility, and comparative emissions from conservation versus conventional tillage practices. EPAapproved models ISCST3 and AERMOD were used with AirMetrics samplers. …


Integrated Modeling Of Nitrate Contamination Of Groundwater In Agriculture-Dominated Watersheds, M. Almasri, Jagath J. Kaluarachchi Sep 2007

Integrated Modeling Of Nitrate Contamination Of Groundwater In Agriculture-Dominated Watersheds, M. Almasri, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

This paper presents and implements a framework for modeling the impact of land use practices and protection alternatives on nitrate pollution of groundwater in agricultural watersheds. The framework utilizes the national land cover database (NLCD) of the United State Geological Survey (USGS) grid and a geographic information system (GIS) to account for the spatial distribution of on-ground nitrogen sources and corresponding loadings. The framework employs a soil nitrogen dynamic model to estimate nitrate leaching to groundwater. These estimates were used in developing a groundwater nitrate fate and transport model. The framework considers both point and non-point sources of nitrogen across …


Modular Neural Network To Predict The Distribution Of Nitrate In Ground Water Using On-Ground Nitrogen Loading And Recharge Data, M. Almasri, Jagath J. Kaluarachchi Jul 2005

Modular Neural Network To Predict The Distribution Of Nitrate In Ground Water Using On-Ground Nitrogen Loading And Recharge Data, M. Almasri, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

Artificial neural networks have proven to be an attractive mathematical tool to represent complex relationships in many branches of hydrology. Due to this attractive feature, neural networks are increasingly being applied in subsurface modeling where intricate physical processes and lack of detailed field data prevail. In this paper, a methodology using modular neural networks (MNN) is proposed to simulate the nitrate concentrations in an agriculture-dominated aquifer. The methodology relies on geographic information system (GIS) tools in the preparation and processing of the MNN input–output data. The basic premise followed in developing the MNN input–output response patterns is to designate the …


Systematic Framework For Evaluating Treated Wastewater Usage In Agricultural Irrigation, Yasser Kamal Nazzal May 2005

Systematic Framework For Evaluating Treated Wastewater Usage In Agricultural Irrigation, Yasser Kamal Nazzal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A general systematic framework with several sub-frameworks was developed to help managers make informed decisions related to the reuse of treated wastewater in agricultural irrigation. The framework involves the identification and evaluation of the short- and long-term effects of using treated wastewater with some common constituents of concern (e.g. salts and some specific ions, nutrients, heavy metals, organic compounds, and microorganisms) on the environmental elements (crop, soils, surface water, and groundwater), and on the public health. Local and/ or international standards, criteria, and guidelines related to agricultural reuse are applied to the evaluation of the effects. Based on the evaluation …


Modeling For Optimal Management Of Agricultural And Domestic Wastewater Loading To Streams, Muhammad Shafqat Ejaz, Richard C. Peralta Apr 1995

Modeling For Optimal Management Of Agricultural And Domestic Wastewater Loading To Streams, Muhammad Shafqat Ejaz, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

A simulation/optimization (S/0) model to aid managing multiobjective wastewater loading to streams while maintaining adequate downstream water quality is presented. The conflicting objectives are to maximize the human and dairy cattle populations from which treated wastewater can be discharged to the river system. Nonindustrial municipal (domestic) wastewater undergoes primary and secondary treatment by a sewage treatment plant (STP) before entering as a steady point source. Dairy wastewater is treated by overland flow (OLF) land treatment before entering the stream as a controlled steady diffuse source. Maximum dual-source loading strategies which do not degrade downstream water quality beyond specified limits are …