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Assessment Of Integrated Nutrient Management Practices On Soil Health And Nitrogen Efficiency In Cropping Systems, María José Oviedo Ventura

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

Groundwater quality in Nebraska is threatened by non-point source contributions of nitrate-nitrogen, primarily by agricultural systems. Intensive crop and livestock production that neglects the value of manure in crop fertility plans can contribute to soil degradation and natural resource impairment. The purpose of this study is to evaluate opportunities to improve agricultural nutrient management throughout Nebraska by quantifying opportunities for manure distribution, evaluating soil health implications of organic and inorganic soil amendments, and assessing nutrient management practices focused on reducing nitrate leaching in agricultural soils.

This study described in Chapter 2 provides a spatial illustration of nitrogen and phosphorus balances …

Studies On Air Injection In A Wastewater-Fed Subsurface Drip Irrigation System, Henry A. Gonzalez Hernandez

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

In 2020, the Ogallala High Plains Aquifer supplied irrigation water for approximately 3.6 million hectares in Nebraska, making it the most irrigated state in the United States. Although Nebraska is highly dependent in groundwater, locations included in the Gering-Fort Laramie Irrigation District (border of Nebraska and Wyoming) rely on surface water resources. In addition to these conventional water sources, using non-conventional alternatives for crop production can be just as important during water shortage times such as the one that e occurred in 2019 with the collapse of the Goshen/Gering-Fort Laramie Canal. Feedlot runoff presents a great opportunity in Nebraska, but …

Evaluation Of A Novel Approach For Assessing Biological Activity In Agricultural Soils, Karla Melgar

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

Soil health is a key factor impacting soil resilience and fertility in crop production systems. Favorable soil physical and biological conditions facilitate plant nutrient absorption and nutrient cycling. Demonstrating to farmers the impacts and changes in soil biological activity under different soil management practices has been a challenge due to the limited availability of inexpensive tools for quantifying this component of soil health. The primary goal of this study was to present a simple and readily accessible tool for evaluating soil biological activity to promote the use of organic amendments in crop fields. Research plots were established in two studies …

Soil Health Effects And Stakeholder Perceptions Of Manure And Woody Biomass Application To Cropland In Nebraska, Linda R. Schott

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

Organic products that have historically been viewed as waste products may improve soil health by adding carbon (C) and nutrients to soil. Two such products are woodchips, generated from forest or rangeland management activities, and livestock manure. In Nebraska, eastern redcedar (Juniperus virginiana L.) is a native but invasive tree species inhibiting rangeland productivity. Livestock manure that is underutilized while inorganic fertilizers are imported for crop production presents a water quality risk by contributing to local- and regional-scale nutrient imbalances. Increasing the responsible use of livestock manure in crop fertility programs to improve sustainability of both livestock and crop farms …

Biomass Gasification: An Alternative Solution To Animal Waste Management, Hanjing Wu

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

The overall goal of this research was to evaluate gasification of animal waste as an alternative manure management strategy, from the standpoints of syngas production and biochar application.

To meet the overall objective, the thermogravimetric characteristics of dairy manure, as a thermochemical conversion feedstock, were studied firstly. Then, gasification technology was applied to dairy manure and feedlot manure using a fluidized-bed laboratory-scale gasifier. In addition, biochar derived from the feedlot manure was examined for its effects on nutrient leaching as a soil amendment. Finally, a life cycle assessment was conducted to evaluate greenhouse gas emissions of two feedlot manure management …