Nitrogen fertilization and crop diversity effects on soil carbon and nitrogen cycling in Iowa cropland

Nitrogen is critical to sustaining the profitability and productivity of agricultural systems. However, plant-available forms of N are highly mobile and cropland N losses have negative environmental consequences. Nitrogen management strategies differ depending on the farming system, with diverse crop rotations (i.e., those including perennial legume crops) and integrated crop-livestock systems relying primarily on biologically-fixed and recycled N, and simple maize (Zea mays L.)-based systems relying primarily on synthetic N fertilizer inputs. The goal of this research was to investigate C and N cycling in farming systems that span a range of N management strategies and to use this knowledge to advance sustainable N management. Within continuous maize and maize-soybean [Glycine max (L.) Merr.] systems at four Iowa locations, I assessed changes in surface soil organic C (SOC) content over time across a range of N fertilizer rates. I found that N fertilization increased SOC content, with the greatest SOC storage in the optimally-fertilized continuous maize treatment. Using the continuous maize plots at two of these long-term N rate experiments, I investigated legacy impacts of N inputs on fertilizer N use efficiency by tracing isotopically-labeled N fertilizer into crop and soil pools. Fertilizer N recovery was less than 50% at both locations and exhibited a curvilinear response to historical N rate. In my third study, I used three long-term field experiments to determine the impact of crop rotation diversity on SOC content, biochemical composition, and distribution among physical fractions at different depths. Despite greater belowground C inputs in the diverse rotations, crop rotation diversity had inconsistent effects on SOC stocks, and minimal impact on the mechanisms of SOC storage. Finally, I compared the profitability of simple cash grain and integrated crop-livestock systems. The analysis revealed no effect of farming system on profitability, but indicated that more labor is required in the integrated crop-livestock system. The results indicate that simple maize-based systems receiving agronomically optimum synthetic N inputs can sustain SOC and provide adequate financial returns, but result in high N losses from cropland. The adoption of biologically-based N management would reduce cropland N losses with minimal profit loss

The Hartley site (FaNp-19) and the use of sandhill environments in the late precontact period

The Hartley site (FaNp-19) is a Late Precontact Period multicomponent habitation and bison kill and processing site located on the periphery of a sand dune environment surrounded by grasslands. The Hartley site, located within the Saskatoon city limits, was originally identified by Ken Cronk and members of the Saskatoon Archaeological Society in the 1950’s. Subsequent excavations by Millenium Consulting Ltd., the University of Saskatchewan, Western Heritage Services Inc., and Stantec Consulting Ltd. have all added to the database of knowledge pertaining to this site. Radiometric dates and the recovery of artifacts characteristic of the Avonlea Horizon, the Old Women’s Phase, and the Mortlach Phase have demonstrated that this region was a popular place for occupation and bison procurement during the Late Precontact Period. A detailed analysis of the faunal remains recovered from the area known as the Wooded Hollow has demonstrated that this assemblage differs significantly from the remains recovered from the previously researched Brushy Depression. It appears that bison were being heavily harvested and that the use of secondary faunal sources was extremely limited. Determination of seasonality is based on cluster and discriminant function analysis of carpal, tarsal, longbone and phalange data. The resulting herd structure of almost equal numbers of males and females suggests an occupation during the rut, or the fall months. Some immature elements and non-bison remains suggest occupation may have occurred in the spring. It is therefore possible that this region was utilized over a period of time for the purposes of procuring animals from the spring to the fall months. The complete lack of foetal bone in this region suggests that, unlike in the Brushy Depression, the Wooded Hollow was not occupied during the winter months. Taphonomic factors were considered in performing a complete faunal analysis of this thesis. Non-human agents and associated processes suggest that the assemblage was buried quickly after the site was vacated. The extremely fragmented nature of the assemblage, however, suggests that humans had a greater effect on the assemblage than the non-human agents. Based on breakage patterns it is determined that these remains were being processed for the purposes of both marrow and grease extraction. Application of a site determination model also suggests that it is likely that both kill and processing activities occurred in this area. Location of the Hartley site within a dune environment is linked to the activities that occurred at this site. A review of ethnographic accounts of bison pounding and surrounding activities has revealed that availability of ecological resources such as wood and necessary topographic features characteristic of dune environments were essential to the success of bison procurement. Although it has been suggested that settlement of these regions is also linked to the variety and stability of resources in ‘ecotones’, or areas of resource overlap, between grassland and sandhill environments, a review of several faunal assemblages from various similar Northern Plains assemblages reveals that bison was by far the dominant species exploited. Variety in terms of faunal resources may not have been a factor at all. It is therefore suggested in this thesis that settlement on the periphery of sandhill environments is linked to the presence of bison in the surrounding grassland region, as well as to the stability of the resources in wetland areas supported by high water tables in the dune environments. Also known as ‘ecological islands’ these regions may have been more stable in terms of essential resources such as wood and other botanical resources, in addition to providing areas of shelter during the colder winter months. It is concluded that settlement and large scale bison procurement activities in several sandhill environments on the Northern Plains is tightly linked to availability of bison, the availability of wood, a conducive topographic setting, and the stability of resources in these ‘ecological islands’

A Troop, a Raft, a Bed

A Troop, a Raft, a Bed tells the interwoven fictional stories of three major animals (the mountain gorilla, the Adélie penguin, and the American eel) and four transitional animals (the white stork, the humpback whale, the common octopus, and the great white shark). The stories are told from the animals\u27 perspectives, and are written with language that considers each animal\u27s unique intelligence, mind, and behavior. These stories seek to communicate how animals around the world may be experiencing the various effects of climate change and global warming

The Impact of Lyric Choices on Spiritual Edification

Modern Christian worship music has gained influence within the evangelical community. The words of these songs, sung corporately, have the potential to influence the spiritual lives of church congregants, making it important for worship leaders and songwriters to identify the most beneficial lyrics. Despite numerous opinions about theological and personally relevant lyrics, little research has been conducted on the spiritual effects of lyric content within the lives of Christian believers. Diminutive scholarly inquiry has been limited to historical, theological or qualitative methodologies. Utilizing the Positive and Negative Affect Schedule (PANAS) and the Spiritual Transcendence Index (STI), this quantitative quasi-experimental study employed a pretest/posttest design to determine whether worship lyrics, in general, led to stronger perceptions of spiritual edification and if integrated lyrics led to stronger perceptions of spiritual edification than lyrics that are either emotionally- or theologically-driven. The study attempted to identify lyric choices that promoted strong personal perceptions of spiritual edification in a sample of 70 evangelical believers between the ages of 18-23 years of age who attended a large university in the Mid-Atlantic United States and were currently enrolled in an introductory worship course. The results showed a statistically significant difference in spiritual edification from pretest to posttest after exposure to worship lyrics in general. In addition, there was a significantly higher spiritual edification score in the integrated lyric group, as compared to the emotional lyric group. However, there was no significant difference between an integrated and theological lyric approach on posttest spiritual edification scores. The results suggested that the lyrics of worship songs may aid in promoting spiritual edification and that there is merit in integrating both relational and theological components

Barriers to cardiovascular disease secondary prevention care in the West Bank, Palestine - A health professional perspective

Abstract Background Non-communicable diseases (NCDs) - including cardiovascular disease (CVD), cancer and diabetes - have become a significant global burden on health. Particularly concerning are CVD rates, causing approximately 18 million deaths worldwide every year. The statistics show that the disease is no longer a predominantly high-income country phenomenon, but affects, increasingly, countries in both developing regions and conflict-affected areas. In the occupied Palestinian territory (oPt), the focus of this article, CVD ranks top of ten NCD killers, accounting for approximately 37.6% of deaths. Key risk factors discerned in primary care settings have been related to both structural determinants (i.e. the Israeli occupation) and individual behavioural factors. Unfortunately, no data are available for secondary care settings in the region and, consequently, little is known about patients and their capacity for risk factor behaviour change to manage their CVD. To begin closing this gap in knowledge, our study provides insight into cardiovascular disease secondary prevention care with the overall aim to enhance the understanding of the complexities of managing NCDs like CVD in conflict-affected settings. Specifically, research was carried out among Palestinian health professionals who specialise in coronary artery disease in the West Bank to elicit their views on (a) how socio-political, health system and individual behavioural factors might hinder patients to change their health behaviour and impact on the provision of healthcare and (b) possible solutions for overcoming identified barriers to behaviour change on societal as well as individual-patient levels within secondary care provision in a context of protracted conflict. Methods This study is based on a qualitative approach in order to provide more in-depth information about health beliefs and behaviours, experiences and views of health professionals with regards to CVD secondary care. In total, 12 semi-structured interviews were conducted among doctors providing treatment to patients with CVD in secondary care settings. Interviews focused on health professionals’ perspectives on risk factors and perceived barriers to behaviour change among known CVD patients receiving secondary care. Interviewees were also asked to propose possible actions that could be taken to overcome the identified barriers at both societal and individual patient levels. All interviews were digitally recorded, transcribed and analysed using thematic analysis. Results Study results confirmed our prior theory of the complex entanglement of socio-political, health system and individual-level factors with regards to CVD experience, health-seeking and treatment. Also confirmed was our assumption that it is crucial to understand experts’ definitions and approaches to treatment in order to grasp their visions for appropriate and improved prevention and treatment options. In particular, study participants highlighted how political determinants, notably the detrimental impact of the Israeli occupation, and social determinants, directly and indirectly influence behavioural determinants due to physical and bureaucratic barriers to accessing health facilities, economic hardship and chronic stress. These stressors, in turn, were perceived as having a negative effect on individual behavioural risk factors including smoking, unhealthy diet and an increasingly sedentary lifestyle. Proposed solutions included more focused interventions from the Ministry of Health as well as surveillance, primary prevention and health promotion, and management to positively effect behaviour change in order to address the growing burden of CVD in the region. Conclusions The study has highlighted medical professionals’ perceptions of how structural and individual behavioural determinants influence their own and individual patient’s abilities to manage cardiovascular risk factors in a setting affected by chronic conflict. Consequently, we propose that medical and social intervention strategies generally used to address CVD risk, be strategically adapted in order to be useful and effective in contexts of armed conflict. Specifically, we call for a solid understanding of the socio-political context and existing health services as well as health providers’ and patients’ health beliefs and related behaviours when developing future health options aimed at addressing CVD in the region. Moreover, for health provision to be effective as well as sustainable, attention needs to be given above all towards a solution for political change

The uncertainty contagion: Revealing the interrelated, cascading uncertainties of managed retreat

Managed retreat presents a dilemma for at-risk communities, and the planning practitioners and decisionmakers working to address natural hazard and climate change risks. The dilemma boils down to the countervailing imperatives of moving out of harm’s way versus retaining ties to community and place. While there are growing calls for its use, managed retreat remains challenging in practice—across diverse settings. The approach has been tested with varied success in a number of countries, but significant uncertainties remain, such as regarding who ‘manages’ it, when and how it should occur, at whose cost, and to where? Drawing upon a case study of managed retreat in New Zealand, this research uncovers intersecting and compounding arenas of uncertainty regarding the approach, responsibilities, legality, funding, politics and logistics of managed retreat. Where uncertainty is present in one domain, it spreads into others creating a cascading series of political, personal and professional risks that impact trust in science and authority and affect people’s lives and risk exposure. In revealing these mutually dependent dimensions of uncertainty, we argue there is merit in refocusing attention away from policy deficits, barrier approaches or technical assessments as a means to provide ‘certainty’, to instead focus on the relations between forms of knowledge and coordinating interactions between the diverse arenas: scientific, governance, financial, political and socio-cultural; otherwise uncertainty can spread like a contagion, making inaction more likely

Farm Energy: Tracking the energy use on your farm

Find out how to track your energy use on the farm with a simple energy log by using the provided Excel file linked within the PDF.https://lib.dr.iastate.edu/extension_ag_pubs/1034/thumbnail.jp

I Just Need Two Credits: Looking at Motivation When Redesigning an Online Credit-bearing Information Literacy Course

Although a 2-credit hour information literacy course had high enrollment, with multiple sections offered each year across several campuses, course completion rates were not as high as hoped. Originally designed for freshman or sophomores, many upper-level students were enrolling in the course because they needed the credit hours, not because of interest in the course content, and overall engagement with the course material was low. With these concerns in mind, we undertook a team project to redesign the course. In this presentation, we will highlight the significant changes we made to course focus and content that were intended to increase the relevance to students at all levels, make the course more engaging, and improve internal motivation for completion. These changes included decreased emphasis on academic research scenarios, increased emphasis on information use in the workplace and everyday life, the addition of resume building text, unique discussion boards, and new content related to students’ roles as information creators and sharers. When making such changes, we shifted focus from learning how to search to understanding what it means to be a responsible digital citizen