Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 5 of 5

Full-Text Articles in Engineering

Variable Rate Irrigation Using A Spatial Evapotranspiration Model With Remote Sensing Imagery And Soil Water Content Measurements, Sandeep Bhatti Dec 2018

Variable Rate Irrigation Using A Spatial Evapotranspiration Model With Remote Sensing Imagery And Soil Water Content Measurements, Sandeep Bhatti

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Variable rate irrigation may help in intensification of agriculture by producing more yield per unit inputs. Real time spatial information about water balance components is important for designing VRI prescription maps. This work involved use of a spatial evapotranspiration model for studying spatial variability in an agricultural field at the Eastern Nebraska Research and Extension Center near Mead, Nebraska. Imagery from unmanned aerial systems and Landsat were used as input for the spatial evapotranspiration model. Other inputs into the model were soil water content measurements from neutron probes, weather data, crop data, previous irrigation prescriptions, and soil properties for the …


Integration Of Remote Sensing And Proximal Sensing For Improvement Of Field Scale Water Management, Foad Foolad Jun 2018

Integration Of Remote Sensing And Proximal Sensing For Improvement Of Field Scale Water Management, Foad Foolad

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Water is one of the most precious natural resources, and sustainable water resources development ‎‎is a significant challenge facing water managers over the coming decades. Accurate estimation of ‎‎the different components of the hydrologic cycle is key for water managers and planners in order ‎‎to achieve sustainable water resources development. The primary goal of this dissertation was to ‎investigate techniques to combine datasets acquired by remote and proximal sensing and in-situ ‎sensors for the improvement of monitoring near surface water fluxes. This dissertation is ‎separated into three site-specific case studies. First study, investigated the feasibility of using ‎inverse vadose zone …


Evaluation Of A Hybrid Reflectance-Based Crop Coefficient And Energy Balance Evapotranspiration Model For Irrigation Management, J. Burdette Barker, Christopher M. U. Neale, Derek M. Heeren, Andrew E. Suyker Apr 2018

Evaluation Of A Hybrid Reflectance-Based Crop Coefficient And Energy Balance Evapotranspiration Model For Irrigation Management, J. Burdette Barker, Christopher M. U. Neale, Derek M. Heeren, Andrew E. Suyker

Biological Systems Engineering: Papers and Publications

Accurate generation of spatial soil water maps is useful for many types of irrigation management. A hybrid remote sensing evapotranspiration (ET) model combining reflectance-based basal crop coefficients (Kcbrf) and a two-source energy balance (TSEB) model was modified and validated for use in real-time irrigation management. We modeled spatial ET for maize and soybean fields in eastern Nebraska for the 2011-2013 growing seasons. We used Landsat 5, 7, and 8 imagery as remote sensing inputs. In the TSEB, we used the Priestly-Taylor (PT) approximation for canopy latent heat flux, as in the original model formulations. We also used the …


Crop Evapotranspiration, Irrigationwater Requirement And Water Productivity Of Maize From Meteorological Data Under Semiarid Climate, Koffi Djaman, Michael O'Neill, Curtis K. Owen, Daniel Smeal, Komlan Koudahe, Margaret West, Samuel Allen, Kevin Lombard, Suat Irmak Jan 2018

Crop Evapotranspiration, Irrigationwater Requirement And Water Productivity Of Maize From Meteorological Data Under Semiarid Climate, Koffi Djaman, Michael O'Neill, Curtis K. Owen, Daniel Smeal, Komlan Koudahe, Margaret West, Samuel Allen, Kevin Lombard, Suat Irmak

Biological Systems Engineering: Papers and Publications

Under the semiarid climate of the Southwest United States, accurate estimation of crop water use is important for water management and planning under conservation agriculture. The objectives of this study were to estimate maize water use and water productivity in the Four Corners region of New Mexico. Maize was grown under full irrigation during the 2011, 2012, 2013, 2014 and 2017 seasons at the Agricultural Science Center at Farmington (NM). Seasonal amounts of applied irrigation varied from 576.6 to 1051.6 mm and averaged 837.7 mm and the total water supply varied from 693.4 to 1140.5 mm. Maize actual evapotranspiration was …


Evaluation Of Variable Rate Irrigation Using A Remote-Sensing-Based Model, John Burdette Barker, Derek M. Heeren, Christopher M.U. Neale, Daran Rudnick Jan 2018

Evaluation Of Variable Rate Irrigation Using A Remote-Sensing-Based Model, John Burdette Barker, Derek M. Heeren, Christopher M.U. Neale, Daran Rudnick

Biological Systems Engineering: Papers and Publications

Improvements in soil water balance modeling can be beneficial for optimizing irrigation management to account for spatial variability in soil properties and evapotranspiration (ET). A remote-sensing-based ET and water balance model was tested for irrigation management in an experiment at two University of Nebraska-Lincoln research sites located near Mead and Brule, Nebraska. Both fields included a center pivot equipped with variable rate irrigation (VRI). The study included maize in 2015 and 2016 and soybean in 2016 at Mead, and maize in 2016 at Brule, for a total of 210 plot-years. Four irrigation treatments were applied at Mead, including: VRI based …