Soluble phosphorus fertilizer is bound in the soil rapidly after application in soils high in calcium. A fertilizer additive known as AVAIL® (J.R. Simplot Company) is purported to keep applied phosphorus fertilizer more available to plants by binding to soil minerals such as calcium, magnesium, and iron, thereby reducing phosphorus binding. This could prove useful due to the attraction of AVAIL® with cations such as Ca2+, but is fairly unstudied for dryland wheat production on alkaline, calcium-rich soils. The objective of this study is to evaluate the effect of low-rate fertilizer treatments with AVAIL® on dryland small grain yield on calcium-rich, eroded hillslopes in a fallow-wheat crop rotation. Two experiments were conducted to determine treatment effects on yield and grain quality for (1) above-ground dispersed (broadcast) application of monoammonium phosphate (MAP; 52% P2O5 content) fertilizer in the spring (2017), and (2) fall application of MAP incorporated with the seed (banded) at planting (2018). Fertilizer treatments were the recommended rate (60 lbs/ac) or one-half the recommended rate (30 lbs/ac) for dryland small grain, with or without AVAIL® (four treatments), replicated four times in a strip-block design for the 2017 experiment and replicated 3 times in a randomized complete block design for the 2018 experiment. Experimental blocks were assigned to hillslope erosional severity groups. The erosional severity groups were v designated (non-eroded, slightly eroded, highly eroded, and depositional slope segments). Hillslope segmentation allowed for correlations between calcium carbonate, organic matter, and yield levels across treatments. Results from the broadcast study indicate that there was no yield advantage of any treatment at any level of erosional severity, saving a grower $20.30/acre by applying 30 lbs/acre of MAP. However, 30 lbs/acre of MAP with AVAIL® showed similar yield to 60 lbs/acre of MAP without AVAIL®, potentially saving a grower $6.42/acre over standard growing practices. The incorporated study also indicated that there was no reliable yield advantage of any fertilizer treatment at any level of erosional severity, saving a grower $15.37/acre by applying 30 lbs/acre of MAP. Neither treatment with AVAIL had greater yield or profit than those without AVAIL. Profit for the 60 lbs/acre of MAP treatment narrowly outperformed 30 lbs/acre of MAP by $1.73/acre, indicating that growers may be able to reduce phosphorus use under dryland growing conditions with optimal fertilizer placement.

Wildlife managers have fed elk in North America for nearly 100 years. Giving winter feed to elk can compensate for a shortage of natural winter range and may boost elk populations while also helping prevent commingling with livestock and depredation of winter feed intended for livestock. In contrast to these benefits of supplemental feeding, there are economic and environmental costs associated with feeding, and elk herds that winter on feeding grounds have a higher risk of contracting and transmitting disease. Brucellosis is of primary concern now, and Chronic Wasting Disease may be in the future. Many see the discontinuation of winter-feeding programs as a necessary step for decreasing the risk of disease spread due to high animal densities associated with feeding during winter. My research evaluated the use of behavioral training to reduce reliance on supplemental winter feeding of elk, while minimizing population reductions and human-wildlife conflicts. My study was conducted at Deseret Land & Livestock (DLL) in Rich County, UT, where managers at DLL have over 20 years of data on elk feeding during winters of varying intensities. I tested the effectiveness of range improvements, strategic cattle grazing, dispersed supplemental feeding, hunting, and herding to distribute and hold elk in desired areas during winter. I compared elk numbers on the feed ground during this study with historic data on DLL, and also contrasted elk responses with other comparable feed sites in Wyoming that served as controls. In 2 mild winters we completely eliminated elk feeding without incident and were able to reduce the quantity and duration of feeding during 1 severe winter. Since the conclusion of my study, DLL has further reduced quantity and duration of feeding during severe winters, and has completely eliminated feeding in light winters. Based on a Before After Control Impact (BACI) analysis, the reduction in the proportion of the elk population fed at the study site was significantly less than the proportion of the elk populations fed at the control sites in Wyoming (P = 0.057). Based on these results, I anticipate wildlife managers can decrease dependence on costly supplemental winter feeding and reduce the risks of disease while keeping human-wildlife conflicts at a minimum. This research illustrates an adaptive method that can enable wildlife managers to keep elk populations in northern Utah at or near their current size, while constraining disease outbreak and transmission risks within "acceptable" levels.

Although there is an abudance of material available concering forage consumption by livestock on pasture land and in the feed lot, there is relatively little known about the grazing habits and forage preferences of livestock under range conditions. There has been still less scientific effort expended toward solving the riddle of the grazing animal's diet under winter range conditions. Investigators have suggested means to determine the quantity of forage available on range areas, the carrying capacities of range lands, and methods of determining the degree to which forage has been utilized. The diet of the foraging animal is affected by the quantity of forage availalbe, and the capacity of range lands to support grazing and the degree to which various species are utilized are directly dependent upon the diet, yet virtually nothing is known about the actual compositions of this diet as selected by the animal on the range. There is need for additional scientific information concerning choice of species by the foraging animal and the factors which affect this selection. Basic information of this nature must be known before scientific range management can be applied. Sheep are known to prefer certain plants, and likewise certain portions of these plants. In addition weather, stage of maturity, intensity of use, and plant associations all affect the sheep's diet, and make interpretations and calculations still more complex. This study was designed to determine on the winter range the quantity of forage available to grazing animals, thes species composition of the animal's diet, and to evaluate, where possible, factors affecting the diet.

Orbital ATK tests horizontally restrained solid rocket motors (SRMs) in Promontory, Utah, USA. During SRMs tests, an estimated 1.5 million kg (~3.3 million lbs.) of entrained soil and combustion products (mainly aluminum oxide, gaseous hydrogen chloride, and water) are deposited over a wide area. Local farmers have expressed concerns regarding the deposition of this material, referred to as Test Fire Soil (TFS), on crops surrounding the test site. Greenhouse studies of mature corn and alfalfa (54 days to harvest) exposed to a worse case TFS deposition density to soil (3200-g/m2) resulted in reductions in germination and plant growth. Application of TFS only on leaves caused visual changes in leaf appearance (e.g. “burning”) but did not impact on growth. The visual damage to the leaves was thought to be caused by the high chloride in the TFS. The pH (measured from 2-10 in the field) of the TFS was also thought to be a potential cause of the visual damage. Follow-up studies were conducted using younger corn, alfalfa and winter wheat (12-54 days from emergence), to evaluate the impact of a more typical TFS deposition density and application scenario. The relationship between deposition amount and the crop impact was also examined. Impact was evaluated by comparing the growth, tissue composition (focusing on chloride and aluminum) and chlorophyll content of controls relative to the treatments. The individual effects of chloride and pH on corn leaves were determined by monitoring visual appearance and chlorophyll content. Leaves exposed to a typical TFS deposition loading (70-g/m2) did not contain elevated chloride or aluminum levels relative to the controls. Higher TFS loadings (700-g/m2 and 3200-g/m2) resulted in significantly elevated chloride content in corn leaves at 29 days from emergence. Corn leaves treated with TFS at the 700-g/m2 loading 12 days from emergence had comparable chloride levels to controls. High and low pH and chloride solutions visually impacted corn leaves and reduced leaf chlorophyll. This study indicated SRMs testing can be conducted under typical conditions during the juvenile growth stages of field corn, alfalfa, and winter wheat without adverse impact on crop yield and plant tissue composition.

Raphanus raphanistrum L. (wild radish) is a widespread and economically problematic weed of winter crops including wheat (Triticum aestivum L.) in southern Australia. Management of the weed is achieved by a range of non-chemical and chemical techniques. Current management is failing to contain the weed, which is increasing in abundance and distribution. The characteristics of staggered recruitment, dormancy, rapid growth, competitive ability and high levels of seed production contribute to its persistence. The literature review concludes that weeds formed the basis for perpetuation of R. raphanistrum, a claim further investigated by simulation modeling. The effective management of R. raphanistrum should aim to achieve declining populations and this requires the integration of all factors that regulate seed production. Reducing seed production of R. raphanistrum in wheat can be achieved by applying herbicides at reproductive stages of development. This technique has been demonstrated to be an effective, safe and practical method of reducing seed production of R. raphanistrum in wheat. Reducing seed production of R. raphanistrum by herbicides applied at reproductive stages of development is a technique that can be incorporated into an integrated weed management program to improve control / Doctor of Philosophy (PhD)

<p>Water vapour is the most important greenhouse gas and plays a fundamental role in the climate system and for the chemistry of the Earth's atmosphere. This thesis presents observations of water vapour in the middle atmosphere with a particular focus on the mesosphere. The majority of these observations presented in this thesis have been performed by the Swedish satellite Odin, providing global observations since 2001. Further observations come from the Hygrosonde-2 campaign in December 2001 based on balloon and rocket-borne measurements. A general overview of Odin's water vapour measurements in the middle atmosphere is given. The optimisation of the mesospheric water vapour retrieval is presented in detail.</p><p>The analysis of the observations has focused mainly on different dynamical aspects utilising the characteristic of water vapour as a dynamical tracer in the middle atmosphere. One application is the mesospheric part of the semi-annual oscillation (SAO). The observations reveal that this oscillation is the dominant pattern of variability between 30°S and 10°N in the mesosphere up to an altitude of 80 km. Above 90 km the SAO is dominating at all latitudes in the tropics and subtropics. It is shown that the SAO exhibits a distinct phase change between 75 km and 80 km in the tropical region.</p><p>This thesis also presents the first satellite observations of water vapour in the altitude range between 90 km and 110 km, extending the observational database up into the lower thermosphere. In the polar regions water vapour exhibits the annual maximum during winter time above 95 km, mainly caused by upwelling during this season. This behaviour is different from that observed in the subjacent part of the mesosphere where the annual maximum occurs during summer time.</p><p>The Hygrosonde-2 campaign provided a high resolution measurement of water vapour in the vicinity of the polar vortex edge. This edge prevents horizontal transport causing different water vapour characteristics inside and outside the polar vortex. The observations show that this separating behaviour extends high up into the mesosphere. Small scale transitions in the Hygrosonde-2 profile between conditions inside and outside the vortex coincided with wind shears caused by gravity waves.</p>

<p>This licentiate thesis investigates the decision-making process behind the regulation of winter shipping along the coast of the northern part of Sweden, the Norrland region, in the period 1940-1975. The licentiate thesis examines two aspects of this decision-making process. First, how the regulations in the field of winter shipping were designed in the period. Second, this work examines the underlying factors behind this regulatory outcome on the premise that the regulatory design in the field was the result of an interaction between the regulating actors in the government and their political and economic institutional context.</p><p>As for the first issue, it is demonstrated that the period 1940-1975 was characterised by a regulatory ambition to expand winter shipping along the coast of Norrland. This meant that the government made substantial investments in ice-breakers during the period, which gradually expanded the shipping season until the target of year-round shipping even to the northernmost ports was established in the first part of the 1970s. Accordingly, those dues for ice-breaker services proposed by several committees that investigated the issue were never introduced. Instead, government-led ice-breaking has served to compensate Norrland as a peripheral region for its relatively high transport costs.</p><p>Regarding the second issue, it is showed that the decision-making process was influenced by developments at different policy levels of the government hierarchy. In the period 1940-1964, when a public authority within the maritime sector emerged and was consolidated, developments at the maritime sector level affected the decision-making process to a large extent. In turn, the period after 1964 witnessed a change in government policy towards the Norrland region as a more interventionist regional and industrial policy than earlier was implemented. This meant that the decision-making process to a larger extent was influenced by factors originating from a macro policy level.</p><p>During the decision-making process, actors at both the maritime sector level and the macro level emphasized the importance of government-regulated winter shipping for the regional industrialization of the Norrland region in terms that reflected the aims and interests of their policy levels. In this respect, actors in the maritime sector pointed to the role of winter shipping as a trade policy instrument while actors who represented the interests of regional development policy and industrial policy considered the expansion of winter shipping as crucial in achieving the general ambition to create a geographically egalitarian welfare state, characterised by high levels of growth and low unemployment.</p>

Mycosphaerella graminicola (anamorph Septoria tritici) causes Septoria tritici blotch, a globally important disease of winter wheat. Resistance and pathogenicity generally vary quantitatively. The pathogen reproduces both sexually and asexually, and the pathogen population is highly genetically variable. Several unresolved questions about the epidemiology of this pathosystem are addressed by this research. Among them are whether cultivar-isolate specificity exists, how partial host resistance affects pathogen aggressiveness and sexual reproduction, and how host genotype mixtures influence epidemic progression and pathogenicity. At its release in 1992, the cultivar Gene was highly resistant to M. graminicola, but that resistance had substantially dissolved by 1995. Six of seven isolates collected in 1997 from field plots of Gene were virulent to Gene seedlings in the greenhouse, while 14 of 15 isolates collected from two other cultivars were avirulent to Gene. Gene apparently selected for strains of M. graminicola with specific virulence to it. In a two-year experiment, isolates were collected early and late in the growing season from field plots of three moderately resistant and three susceptible cultivars, and tested on seedlings of the same cultivars in the greenhouse. Isolates were also collected from plots of two susceptible cultivars sprayed with a fungicide to suppress epidemic development. Isolate populations were more aggressive when derived from moderately resistant than from susceptible cultivars, and more aggressive from fungicide-sprayed plots than from unsprayed plots of the same cultivars. Over 5,000 fruiting bodies were collected in three years from replicated field plots of eight cultivars with different levels of resistance. The fruiting bodies were identified as M. graminicola ascocarps or pycnidia, or other. In all three years, the frequency of ascocarps was positively correlated with cultivar susceptibility, as measured by area under the disease progress curve, and was also positively associated with epidemic intensity. For three years, four 1:1 mixtures of a moderately resistant and a susceptible wheat cultivar were planted in replicated field plots. Isolates from the plots were inoculated as bulked populations on greenhouse-grown seedlings of the same four cultivars. Mixture effects on disease progression varied among the years, and were moderately correlated with mixture effects on pathogenicity. / Graduation date: 2002

Studies were conducted in 2004, 2005, and 2006 in south Texas to evaluate fall, winter, and spring weed control for commercial rice production, study tillage intensity and herbicide rate interactions for rice production, and determine the tolerance of red rice ecotypes from Texas rice fields using selected herbicides at varying rates. A single application of any herbicide or combination of herbicides was not adequate for weed control throughout the fall, winter, and spring. Fall applications of clomazone plus flumioxazin provided consistent weed control. Addition of flumioxazin to glyphosate provided excellent winter annual grass control with winter application. A residual herbicide, coupled with the proper contact herbicide is the key to extending control. In 2006, all tillage by herbicide treatments in all studies provided ≥ 90% control of all weed species. The conventional tillage treatment with low herbicide input provided the highest rice grain yield in 2005 and 2006, though they were not significantly different from the spring stale seedbed program with medium or high herbicide input in 2006. In 2006, fall stale seedbed treatments were among the lowest in yield. A stale seedbed program may be useful, but with substantial weed pressure, increasing the intensity of herbicide applications is necessary to overcome the absence of tillage. All rice ecotypes were adequately controlled by glyphosate and only one ecotype was found to be tolerant to 2x rates of both imazethapyr and imazamox. All ecotypes were adequately controlled by 2x rates of more than two of the four herbicides which included imazethapy, imazamox, glufosinate, and glyphosate. Ecotypes from the 3.2 group, genetically similar to the ecotype TX4, appear to be the most likely to exhibit tolerance to a given herbicide. Tolerance to glufosinate was found in 70% of the group 3.2 ecotypes. Sixty percent of ecotypes from group 3.1, genetically similar to Oryza rufipogon were not adequately controlled by glufosinate.

Water vapour is the most important greenhouse gas and plays a fundamental role in the climate system and for the chemistry of the Earth's atmosphere. This thesis presents observations of water vapour in the middle atmosphere with a particular focus on the mesosphere. The majority of these observations presented in this thesis have been performed by the Swedish satellite Odin, providing global observations since 2001. Further observations come from the Hygrosonde-2 campaign in December 2001 based on balloon and rocket-borne measurements. A general overview of Odin's water vapour measurements in the middle atmosphere is given. The optimisation of the mesospheric water vapour retrieval is presented in detail. The analysis of the observations has focused mainly on different dynamical aspects utilising the characteristic of water vapour as a dynamical tracer in the middle atmosphere. One application is the mesospheric part of the semi-annual oscillation (SAO). The observations reveal that this oscillation is the dominant pattern of variability between 30°S and 10°N in the mesosphere up to an altitude of 80 km. Above 90 km the SAO is dominating at all latitudes in the tropics and subtropics. It is shown that the SAO exhibits a distinct phase change between 75 km and 80 km in the tropical region. This thesis also presents the first satellite observations of water vapour in the altitude range between 90 km and 110 km, extending the observational database up into the lower thermosphere. In the polar regions water vapour exhibits the annual maximum during winter time above 95 km, mainly caused by upwelling during this season. This behaviour is different from that observed in the subjacent part of the mesosphere where the annual maximum occurs during summer time. The Hygrosonde-2 campaign provided a high resolution measurement of water vapour in the vicinity of the polar vortex edge. This edge prevents horizontal transport causing different water vapour characteristics inside and outside the polar vortex. The observations show that this separating behaviour extends high up into the mesosphere. Small scale transitions in the Hygrosonde-2 profile between conditions inside and outside the vortex coincided with wind shears caused by gravity waves.