1,190 research outputs found
Innovative Water Management Using Advanced Irrigation Systems and Biochar
Two approaches to water optimization in agriculture are to increase soil water retention and improve the efficiency of irrigation. A soil amendment that has received attention for its ability to increase soil water retention is biochar, the remaining biomass after high C materials have been pyrolyzed (burned with limited oxygen and heat). Two studies were conducted at a total of 10 site-years in Utah from 2018 to 2020 to evaluate how wood biochar influences the productivity and crop quality of irrigated alfalfa (Medicago Sativa L.), corn (Zea mays L.), and wheat (Triticum L.), along with soil water tension. One study included a single biochar rate of 22 Mg ha-1 at two irrigation levels (full vs. partial), where soil-incorporated biochar increased silage corn yield by 12% in 2018 and reduced yield by 10% in 2019. Top-dressed biochar had no impact on alfalfa yield from 2018-2020, in either irrigation rate. The other trial had six to seven biochar rates (0 ā 67 Mg ha-1), plus the addition of wood chips at a single rate (22 Mg ha-1) at one site. This trial displayed a yield decrease of 0.01 Mg ha-1 of wheat grain for each additional Mg ha-1 of biochar applied, however there were no impacts on silage corn production. Data obtained over ten site years showed minimal impacts from biochar on crop yield, quality, or soil water tension, leading us to conclude that wood biochar was not an effective tool for enhancing crop production or conserving irrigation water in arid agriculture.
Most pivot sprinkler package in the Intermountain West are classified as mid-elevation sprinkler application (MESA). Several studies of low elevation spray application (LESA), low energy precision application (LEPA), and mobile drip irrigation (MDI) have demonstrated greater efficiency than MESA, due to less loss between the time that the irrigation water leaves the nozzle and enters the rootzone. However, these advanced sprinkler packages have rarely been tested at a reduced application rate. Eight site-years of data were collected at four Utah farms from 2018 to 2020, to evaluate crop yield and quality responses to full and reduced rates of each system in alfalfa, corn, and small grains. Soil water tension was also measured. Data showed that the advanced systems were sometimes able to maintain yield and quality while applying 15 to 25% less water, yet there were situations where MESA outperformed the advanced systems. This led us to conclude that there is not one style that will have the best results all the time, but that tailoring the package to the field characteristics is where the optimization with these packages can occur. Therefore, this chapter is being published as an Extension Guidebook for farmers
Subsidence Mechanisms of Sedimentary Basins Developed over Accretionary Crust
This thesis uses forward modelling to investigate the formation of intercratonic basins upon accretionary crust. It began from the hypothesis that accretionary crust forms with a near normal thickness crust, but a thin lithosphere inherited from the terranes that compose it. After the accretion process has ceased the lithosphere stabilises and begins to cool, causing it to grow thicker and this in turn drives subsidence of the accretionary crust. A 1-D finite difference computer code was developed to model conductive heat flow through a column of cooling lithosphere and asthenosphere. To test the hypothesis, the subsidence produced by the modelling of this process was compared to the observed subsidence from backstripping numerous basins situated on accretionary crust
The model produced a good fit to the subsidence in a detailed case study of two of the Palaeozoic basins in North Africa. The study was then extended to test the applicability of to accretionary crust globally. It found that while using measured values of the crust and lithospheric thickness for each region the model produced subsidence curves that matched the observed subsidence in each basin. It makes a more coherent argument for the formation of these basins that is able to explain a wider variety of features than other proposed subsidence mechanisms such as slow stretching or dynamic topography. These results suggest that such subsidence is an inherent property of accretionary crust which could influence the evolution of the continental crust over long time periods.
The model was used to investigate the subsidence of the West Siberian Basin and found the subsidence patterns to be consistent with the decay of a plume head which thinned the lithosphere. This subsidence patterns indicate the plume material thinned the lithosphere over an area of 2.5 million km2 resulting in uplift before it cooled and subsided
Practical Improvements for Pivot and Surface Irrigation
Irrigation is critical to meeting global food and fiber demands. Optimizing agricultural irrigation may help sustain production levels, while reducing its demand for water. This research evaluated precision sprinklers and drip irrigation for pivots, five pivot track mitigation tools, three scientific irrigation scheduling (SIS) methods, sensors for surface irrigation cutoff, and automating surface systems to implement surge irrigation. With pivots and surface irrigation being the most common methods for irrigation in the West, small improvements from these tools could result in significant water savings.
Low energy precision application (LEPA) sprinklers and mobile drip irrigation (MDI) were tested on two pivots. LEPA did not often maintain yield, even with similar application amounts to the mid elevation sprinkler application (MESA) control. MDI reduced yield by 6 ā 25% in 2018, while applying half as much water as MESA. In following years, MDI rarely maintained yield, even when applying more than MESA. For LEPA and MDI to maintain yield with less water, the correct situations and proper adaptations must be carefully chosen.
With the intent to improve pivot wheel tracks, installing LEPA around the pivot tower was the best of five tested methods, reducing track depths by 47 ā 63% in one year. Adapting the correct method to field conditions and position on the pivot can result in shallower wheel tracks without sacrificing yield.
The use of soil moisture sensors, a commercial irrigation scheduler, and a free irrigation scheduler to determine irrigation amounts, were compared with the rates chosen by farmers. At some farms, the SIS methods maintained yield with 10-15% less irrigation. These benefits were usually when precipitation was high, which the SIS methods accounted for well.
Surface irrigators found that sensors helped reduce irrigation application by correctly timing the cutoff, saving them time, water, and money. Automation to implement surge irrigation increased irrigation use efficiency by 43% the first year, but had less drastic results in the final year, likely due to the severity of an ongoing drought. These collective results demonstrate that simple water optimization techniques could reduce irrigation diversions by 15 and possibly up to 25% or more in some cases
An adult development psychobiography of C.G. Jung : an application of the theories of Daniel J. Levinson
Sustainable food procurement in British and Irish zoos
Purpose
ā The purpose of this paper is to assess the sustainable food procurement (SFP) of members of the British and Irish Association of Zoos and Aquariums (BIAZA). It also considered the inconsistencies between their animal and human food supply chains, as well as between their procurement priorities and practices.
Design/methodology/approach
ā A quantitative, cross-sectional approach was employed, involving the use of a web-based questionnaire to gather data from 41 BIAZA members across 21 indicators of food sustainability. The results were considered within a sustainable supply chain management (SSCM) framework.
Findings
ā There was considerable variation amongst the issues considered by zoos during the SFP process for their animal and human food operations. For both, local expenditure, nutritional content and packaging reduction were some of the highest scoring indicators in practice and as priorities. The overall levels of SFP were found to be equal between the human and animal food supply chains. Significantly low levels of inconsistency were found between the two, practically and in terms of procurement aspirations. Within both supply chains, there was also very few significant gaps between procurement priorities and actions.
Originality/value
ā The originality of this study lies in its comparison of procurement practices and priorities for two contemporaneous but distinct food supply chains. It demonstrates that it is possible to have a high overall degree of consistency between two parallel, but contrasting, supply chains, as well as between procurement priorities and priorities. It will be of use in SSCM, particularly within values-led organisations.
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Spiritual Development Among Christian Athletes at a Large Christian University
Undergraduate
Applie
Effective double-beta-decay operator for 76Ge and 82Se
We use diagrammatic many-body perturbation theory in combination with
low-momentum interactions derived from chiral effective field theory to
construct effective shell-model transition operators for the neutrinoless
double-beta decay of 76Ge and 82Se. We include all unfolded diagrams to first-
and second-order in the interaction and all singly folded diagrams that can be
constructed from them. The resulting effective operator, which accounts for
physics outside the shell-model space, increases the nuclear matrix element by
about 20% in 76Ge and 30% in 82Se.Comment: 8 pages, 5 figure
Change in parental and peer relationship quality during emerging adulthood Implications for academic, social, and emotional functioning [post-print]
We report on two longitudinal studies, where we examined how stability and change in attachment to parents and peers from the first to last year of college were associated with changes in theoretically relevant outcomes. As expected, students with consistently secure parental and peer attachment evidenced the best academic, social, and emotional functioning overall. Participants with āstable secureā parental attachment reported significant increases in their academic and emotional functioning and their social competencies; on the other hand, students with consistently low parental attachment showed a decline in their emotional functioning. Participants with stable secure peer attachment also reported lower overall levels of depression and loneliness, better social competence, and more favorable attitudes about help-seeking. Finally, students who transitioned from lower to higher parental attachment showed significant declines in loneliness; those transitioning from low to high peer attachment evidenced a significant increase in social functioning. We discuss implications for how college-based programming might serve to forestall declines in parental/peer attachment and/or facilitate skill building among students who identify with a more insecure style at college entry
Structural glaciology of Isunguata Sermia, West Greenland
We present a 1:42,000 scale map of Isunguata Sermia, a land-terminating outlet glacier draining the western-sector of the Greenland Ice Sheet. Structure-from-Motion software applied to ā¼3,600 aerial images collected by a fixed-wing unmanned aerial vehicle in July 2015 allowed us to produce a high resolution (0.3ā
m ground sampling distance (GSD)) orthomosaic and digital elevation model (DEM; 1.5ā
m GSD).These products were used to map and describe the structural, geomorphological and hydrological features of the lower 16ā
km terminus of Isunguata Sermia and include many thousands of crevasses, crevasse traces and supraglacial channels. Additionally, several geomorphological features and pro-glacial hydrological features were identified, including debris-covered ice, lateral moraines and ice-marginal lakes. The map has potential for informing and reconstructing the long-term dynamic history of the glacier, including its response to variable environmental forcing
Testing a model of consultation-based reassurance and back pain outcomes with psychological risk as a moderator: A prospective cohort study.
Objectives: Reassurance is an essential part of treatment for low back pain (LBP), but evidence on effective methods to deliver reassurance remains scarce. The interaction between consultation-based reassurance and patientsā psychological risk is unknown. Our objective was to investigate the relationship between consultation-based reassurance and clinical outcomes at follow-up, in people with and without psychological risk. Methods: We tested the associations between specific reassurance components (data gathering, relationship building, generic reassurance, and cognitive reassurance), patientsā psychological risk (the presence of depression, anxiety, catastrophizing, or fear-avoidance), and postconsultation outcomes including, satisfaction and enablement, disability, pain, and mood at 3-month follow-up. Results: Adjusted linear regression models using data from patients who had recently consulted for LBP in primary care (n=142 in 43 practices) indicated that all reassurance components were strongly associated with increased satisfaction, whereas generic reassurance was significantly associated with postconsultation enablement. Generic reassurance was also associated with lower pain at 3 months, whereas cognitive reassurance was associated with increased pain. A significant interaction was observed between generic reassurance and psychological risk for depression at 3 months: high rates of generic reassurance were associated with lower depression in low-risk patients, but with higher rates of depression for high-risk groups. Discussion: The findings support the hypothesis that different components of reassurance are associated with specific outcomes, and that psychological risk moderates this relationship for depression. Clinicians reassuring behaviors might therefore have the potential to improve outcomes in people with LBP, especially for patients with higher psychological risk profiles
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