Plant Sciencehttp://hdl.handle.net/10211.3/56832024-03-28T11:38:50Z2024-03-28T11:38:50ZPyrolysis of Agricultural Waste Plastic into Diesel and Evaluation of the Carbonaceous Byproduct as a Soil AmendmentJackson, Alexishttp://hdl.handle.net/10211.3/2110352020-04-20T23:11:17Z2019-05-01T00:00:00ZPyrolysis of Agricultural Waste Plastic into Diesel and Evaluation of the Carbonaceous Byproduct as a Soil Amendment
Jackson, Alexis
High density polyethylene[HDPE] from used drip irrigation tubing was
thermochemically broken down through pyrolysis at 500 °C for 20 minutes in the
presence of a clinoptilolite zeolite catalyst to produce pyrolysis oil and a carbonaceous
byproduct. The pyrolysis oil produced had a melting point of 50 °C, a boiling point of 80
°C, and a flash point of 89 °F. The melting point is higher than that of diesel fuel and the
boiling point and flash point are lower than that of diesel fuel. The high melting point
necessitates preheating before use as a fuel and prevents the pyrolysis oil from being a
direct substitute for diesel fuel. The carbonaceous byproduct, when used as a soil
amendment, increased soil water holding capacity and microbial respiration but had not
effect on cation exchange capacity. Two-percent by weight of carbonaceous byproduct
reduced soil hydraulic conductivity and increased nitrate leaching but lower treatment
levels did not affect soil hydraulic conductivity or nitrate leaching. Amended soil had a
slightly increased pH compared to the control. The properties of the pyrolysis oil can
potentially be improved by using a different catalyst or increasing the pyrolysis reaction
time from 20 minutes to several hours. The carbonaceous byproduct can be used as an
effective soil amendment that improves several important soil characteristics.
2019-05-01T00:00:00ZWater use Efficiency and Nitrogen use Efficiency in Drip and Deficit Drip Irrigated Sugar Beets (Beta Vulgaris)Mele, Anthonyhttp://hdl.handle.net/10211.3/2110222020-04-20T23:11:17Z2019-05-01T00:00:00ZWater use Efficiency and Nitrogen use Efficiency in Drip and Deficit Drip Irrigated Sugar Beets (Beta Vulgaris)
Mele, Anthony
Efficient cropping systems emphasize the importance of both water use efficiency
(WUE) and nitrogen use efficiency (NUE). One method of increasing WUE and NUE is
to implement low-volume irrigation practices. Sugar beet, a resilient crop with a
multitude of economical uses, is grown primarily using conventional flood irrigation but
has demonstrated improved resource efficiency when grown under drip irrigation. A
two-year study (2015-2017) was conducted at two different field sites located in the
Central Valley of California and characterized by clay loam (Site A) and sandy loam
(Site B) soils. The experimental design was a split-plot with three replications of
irrigation regime as the main treatment (Drip 100% of ETc, Drip 70% of ETc, and Flood 100% of ETc) and nitrogen (N) rate as the sub-treatment (0, 112, 168, and 224 kg N ha-1).
Best management practices were evaluated based on yield, sucrose yield, above ground
biomass (AGB), relative crop water stress index (rCWSI), WUE, and NUE. At both
sites, root yields of sugar beets were similar for the 100% drip and flood irrigated
treatments. Production under deficit drip (70% of ETc) regimes resulted in the greatest
WUE for AGB, yield, and sucrose yield. Sugar beet yields were not significantly
influenced by N rates. However, fertilization at the lowest N rate (112 kg N haˉ¹) led to
the highest NUE for AGB, yield, sucrose yield, and sucrose production. When assessing
NUE based on both total available soil N and applied N, the NUE for sucrose yield showed a generally strong correlation (r2 ≥ 0.74) to total available soil N at both sites. This study is the first investigation of sugar beets cultivated in the spring under deficit
drip irrigation in California.
2019-05-01T00:00:00ZControlled Environment Vertical Farm Design and the Role of Supplemental Light Quality and Quantity on Chlorophyll and Anthocyanin Content in Selected MicrogreensSmith, Kyra Mariehttp://hdl.handle.net/10211.3/2109062020-04-20T23:11:16Z2018-12-01T00:00:00ZControlled Environment Vertical Farm Design and the Role of Supplemental Light Quality and Quantity on Chlorophyll and Anthocyanin Content in Selected Microgreens
Smith, Kyra Marie
The objective of this project was to examine the role of currently available
supplemental light sources in producing selected hydroponically-grown microgreens-
Wheatgrass (Triticum aestivum), Mustard (Brassica juncea), Shiso (Perilla frutescens),
and Beet (Beta vulgaris) with a specific focus on biosynthesis of the nutritionally
valuable pigments chlorophyll and anthocyanin. The study was specifically designed to
determine if use of lower cost value light sources would result in similar chlorophyll and
anthocyanin concentrations in selected microgreens as higher cost value light sources
would. Additionally, a goal of the project was to build and maintain an economically
feasible controlled hydroponic environment system. The results of this study indicated
that use of the higher cost light source resulted in greater concentrations of chlorophyll a
and b and the use of a lower cost light source resulted in higher anthocyanin
concentration in the selected microgreens.
2018-12-01T00:00:00ZThe effect of succinamic acid 2,2-dimethylhydrazide (Alar) on shoot growth and fruit quality of Santa Rosa plumsYotsuya, Marvin M.http://hdl.handle.net/10211.3/2024332020-04-20T23:11:16Z1972-01-01T00:00:00ZThe effect of succinamic acid 2,2-dimethylhydrazide (Alar) on shoot growth and fruit quality of Santa Rosa plums
Yotsuya, Marvin M.
Succinamic acid, 2,2-dimethylhydrazide (Alar) was applied at various postbloom dates and concentrations to Santa Rosa plum trees in 1970 and 1971. Alar sprays of 2000, 4000, and 8000 ppm applied at fruit pit hardening in 1970 resulted in a significant reduction in shoot length with no significant effect on shoot diameter. An Alar spray of 2000 pmm applied in 1970 resulted in larger fruit; however, the same spray concentration applied in 1971 resulted in smaller fruit. 2000 ppm Alar applied at full bloom resulted in a reduction of soluble solids and pH, and an increase in titratable acids. Alar applied at 2000 ppm two weeks after full bloom, had no effect on fruit quality. The 2000 ppm Alar applied at fruit pit hardening resulted in an increase in soluble solids and pH with a trend towards decreasing titratable acids. A trend towards firmer fruit occurred regardless of the application date of Alar.
1972-01-01T00:00:00Z