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Title: Concepts and mechanisms of cultural ecosystem services in the Mono-Kouffo, Republic of Benin and Michigan, USA : toward an integrated model
Creator: Kraus, Erika Beth
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Ecosystem services science theory highlights the interdependency of people and nature. Ecosystem services (ES) science theory posits that the biophysical ecosystem generates ecosystem services, which are benefits that improve human well-being, identified by beneficiaries. Human action, influenced by human well-being, in turn affects the biophysical system. Social-ecological systems research describes the complex and dynamic feedbacks between the social and ecological components of a given...
Show moreEcosystem services science theory highlights the interdependency of people and nature. Ecosystem services (ES) science theory posits that the biophysical ecosystem generates ecosystem services, which are benefits that improve human well-being, identified by beneficiaries. Human action, influenced by human well-being, in turn affects the biophysical system. Social-ecological systems research describes the complex and dynamic feedbacks between the social and ecological components of a given system. ES science is one way to explore social-ecological systems. Placing ES science within a social-ecological system allows for questions about the social and ecological drivers that affect ecosystem services provision. This dissertation research explores the relative contribution of social and ecological drivers on the provision of cultural ecosystem services (CES) of spirituality, cultural heritage, and cultural identity, in the Mono-Kouffo, Republic of Benin and in Michigan, USA, by characterizing CES and developing conceptual causal loop diagrams (CLDs). Results demonstrate that CES, especially spirituality, heritage, and identity, are strongly overlapping and rely upon social institutions for people to develop the capacity to identify these benefits from nature. Further, results show these particular CES contribute toward a eudaimonic sense of well-being, or of living a good life, as well as feeling well, like being happy and relaxed. A third major finding is that while CES are strongly associated with pro-environmental and pro-social behaviors, the size and ecological quality of the space where CES are identified may likely be relatively small.The results of this research contribute to conceptual development of what cultural ecosystem services are, especially spirituality, cultural heritage, and cultural identity, as well as their mechanisms of provision. Results from both the Republic of Benin and the USA illuminate the social-ecological dynamics of systems where people identify ecosystem services by articulating their actions in and about the woods and how those actions facilitate benefits to their well-being via the woods. The two case studies are used to build causal loop diagrams that are compared and contrasted to contribute knowledge of CES mechanisms and to identify relevant areas of further research. This dissertation research demonstrates the utility of the connectedness to nature scale in incorporating CES in ES assessments and evaluations, and considers the important time-dependent relationship between people's knowledge and skills, the capacity to identify benefits from nature, and the size and quality of the wooded space. The time-dependent relationship emphasizes ways in which people affect nature in a positive way. These points should be further pursued in research and incorporated into policies and practices that affect natural resources and human well-being based on decisions made through ES science.
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Title: Habitat selection by juvenile salmonids in a Lake Michigan tributary
Creator: Nisbet, Mitchell Thomas
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Recruitment of potadromous salmonid populations in the Great Lakes is a combination of annual plantings of hatchery reared fish and natural reproduction. Determining the input of smolts and juveniles from natural sources is critical to our understanding of these populations as they are both economically and recreationally important species. I found Bear Creek to be a potentially important contributor of potadromous salmonids to the Lake Michigan basin, producing approximately 15,000 Rainbow...
Show moreRecruitment of potadromous salmonid populations in the Great Lakes is a combination of annual plantings of hatchery reared fish and natural reproduction. Determining the input of smolts and juveniles from natural sources is critical to our understanding of these populations as they are both economically and recreationally important species. I found Bear Creek to be a potentially important contributor of potadromous salmonids to the Lake Michigan basin, producing approximately 15,000 Rainbow Trout smolts, 5,000 Chinook Salmon smolts, and 23,000 Coho Salmon smolts in addition to supporting 43,000 young-of-year Rainbow Trout, 9,200 young-of-year Brook Trout and 21,000 young-of-year Brown Trout. I concluded that while Bear Creek may produce lower numbers of individual species, the total sum of potadromous salmonids produced is roughly equivalent to other similarly sized Lake Michigan tributaries. I also evaluated microhabitat use by young salmonids in Bear Creek using the modified Chesson's Index. My results showed that young-of-year salmonids tended to select for near shore habitat with finer sediments, in slower moving shallow water that provided both overhead cover and woody debris. This is in contrast to age-1 Rainbow Trout, that selected for more midstream sections of the river with deeper and faster moving currents that still provided overhead cover and woody debris. I also showed that univariate descriptions of habitat preference may not provide an accurate picture of the true habitat utilization of these species.
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Title: The impact of mechanical leaf removal on grapevine physiology, ripening-related phytohormone biology, and fruit quality in (Vitis vinifera L.) Merlot
Creator: VanderWeide, Joshua
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Removal of basal leaves early in the vegetative and reproductive development of grapevines is a tool used to decrease fruit set, lower cluster rot severity, and improve fruit quality. However, the considerable time required for implementation limits its use by grape growers. Efficient mechanization can potentially mitigate these issues, studies are lacking in a cool climate setting where short seasons and humid summers limit grape production. Therefore, the goal of these studies were to...
Show moreRemoval of basal leaves early in the vegetative and reproductive development of grapevines is a tool used to decrease fruit set, lower cluster rot severity, and improve fruit quality. However, the considerable time required for implementation limits its use by grape growers. Efficient mechanization can potentially mitigate these issues, studies are lacking in a cool climate setting where short seasons and humid summers limit grape production. Therefore, the goal of these studies were to compare mechanical leaf removal with the manual removal of six leaves at the pre-bloom and after-bloom phenological stages over two seasons in Pinot Grigio, a tight-clustered cultivar susceptible to bunch rot, and Merlot, which reaches suboptimal fruit quality in some seasons. For Pinot Grigio (Chapter 3), the loss of fruit to gray mold was lowered by all leaf removal treatments in the drier 2017 season, but only manual treatments mitigated loss from sour rot in that year. This indicates that a clear fruit zone and reduced cluster compactness are both needed to lower the effect of cluster rot disease. Only pre-bloom treatments enhanced fruit quality, likely driven by a similar reduction in cluster compactness. The results suggest that mechanical leaf removal at pre-bloom may be used to enhance fruit total soluble solids, while pre-bloom manual removal can be an effective means to reduce fruit loss to sour rot severity.For Merlot (Chapter 4), berry total soluble solids were highest with pre-bloom mechanical treatment. Furthermore, metabolomics analysis revealed that this treatment favored the accumulation of significantly more disubstituted anthocyanins and flavonols and OH-substituted anthocyanins compared with manual application. Given that vine balance was similar between treatments, increased ripening with PB-ME is likely due to enhanced microclimate conditions and higher carbon partitioning through a younger canopy containing basal leaf fragments proximal to fruit. Despite these results, it was not clear which factor was controlling the increase in fruit quality in response to pre-bloom mechanical leaf removal. In Chapter 5, an experiment was established where 60% of leaf area was removed from shoots in three ways: 1) manual removal of 5 leaves (PB-MA), 2) mechanical removal (PB-ME), and 3) simulated mechanical removal (PB-SIM), which was implemented to understand whether PB-ME improves fruit quality via enhanced microclimate conditions, or stress. Major phenylpropanoid classes were enhanced by PB-ME, however neither ABA nor ethylene were similarly altered, suggesting their lack of involvement in promoting phenylpropanoid biosynthesis in response to ELR. Instead, the leaf area at nodes above the fruit-zone was lower in PB-ME compared to C, which increased post-veraison fruit temperature (+2.8°C). These parameters correlated with anthocyanins at harvest. In conclusion, skin phenylpropanoid concentrations are influenced by canopy density above the fruit-zone. Finally, in Chapter 6, the influence of vine balance and light exposure on fruit quality parameters were compared in two locations (Michigan, Italy). Primary metabolism was not significantly altered with the excepting of titratable acidity being decreased by LR8 having the greatest light exposure during ripening. Flavonol biosynthesis was significantly altered by light exposure in both locations, but not by vine balance. The results indicate that fruit exposure to light, rather than source-to-sink balance has a greater influence on flavonoid biosynthesis in grape berries.
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Title: Agronomic and nutrient management strategies to improve winter wheat and sugarbeet plant growth, yield, and quality
Creator: Purucker, Seth James
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Inconsistent winter wheat (Triticum aestivum L.) grain yield responses multiple-input management has generated grower interest in focusing input applications within decreased seeding rates. Field trials were initiated in Richville and Lansing, MI to evaluate the effects of seeding rate, fungicide, plant growth regulator, autumn starter fertilizer, weekly nitrogen (N) applications, and high N management on winter wheat plant growth, grain yield, and expected net return within enhanced (i.e....
Show moreInconsistent winter wheat (Triticum aestivum L.) grain yield responses multiple-input management has generated grower interest in focusing input applications within decreased seeding rates. Field trials were initiated in Richville and Lansing, MI to evaluate the effects of seeding rate, fungicide, plant growth regulator, autumn starter fertilizer, weekly nitrogen (N) applications, and high N management on winter wheat plant growth, grain yield, and expected net return within enhanced (i.e. all inputs) and traditional management (i.e. individual input). Enhanced management increased grain yield 1.2-2.3 Mg ha-1 compared to traditional management in three of four site-years. Despite grain yield increases, expected net return was maximized when utilizing traditional management with only a recommended rate of N.Management practices, such as plant population, N rate, row spacing, and subsurface banded N, have changed as sugarbeet (Beta vulgaris L.) tonnage has increased over the past 10 years, however climatic variability continues to influence sugar production. Two separate field studies were initiated to 1) evaluate plant population, N rate, and subsurface banded N and 2) determine whether row spacing affects the need for subsurface banded N. Across tested N rates, 179 kg N ha-1 produced optimal root yield, quality, and expected net return. Benefits from subsurface banded N existed under dry May-June conditions. Row spacing of 56 cm increased root yield compared to 76 cm rows. Sugarbeet response to management practices may be influenced heavily by environmental conditions and environmental trends should be considered when deliberating management strategies.
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Title: "What do I want to do today?" : state vocational interests, outcomes, and predictors of variation
Creator: Bradburn, Jacob
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Current theory and research in the organizational sciences considers vocational interests to be stable trait preferences, neglecting any short-term within-person variability that occurs. This research project posits that vocational interests display non-trivial state variability, that these state vocational interests differ theoretically from other extant interest constructs, and details a program of research in which the usefulness and nature of these state vocational interests are evaluated...
Show moreCurrent theory and research in the organizational sciences considers vocational interests to be stable trait preferences, neglecting any short-term within-person variability that occurs. This research project posits that vocational interests display non-trivial state variability, that these state vocational interests differ theoretically from other extant interest constructs, and details a program of research in which the usefulness and nature of these state vocational interests are evaluated. Results suggest that state vocational interests display variability of different forms day-to-day, and this variability cannot be attributed to measurement error alone. Individuals were found to differ in the degree to which their interests vary, with several individual difference variables predicting greater variability. State vocational interest congruence was predictive of daily positive affect, intrinsic motivation, engagement, and perseverance. However, state vocational interest congruence did not generally predict daily negative affect. Tentative support was found for situational interests predicting next day state vocational interests and for state vocational interests predicting situational interests, suggesting a positive feedback loop between these constructs. Theoretical and practical implications of this research are discussed.
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Title: The role of affect in binge eating phenotypes : an examination of individual differences in emotion experience and interactions with ovarian hormones
Creator: Mikhail, Megan Elizabeth
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Ovarian hormones significantly influence dysregulated eating in females. However, most women do not develop appreciable disordered eating, suggesting that ovarian hormones may not affect all women equally. In the first study of this thesis, I examined whether individual differences in trait negative affect (NA) moderate ovarian hormone-dysregulated eating associations in 446 women who provided saliva samples for hormone measurements and ratings of NA and emotional eating daily for 45...
Show moreOvarian hormones significantly influence dysregulated eating in females. However, most women do not develop appreciable disordered eating, suggesting that ovarian hormones may not affect all women equally. In the first study of this thesis, I examined whether individual differences in trait negative affect (NA) moderate ovarian hormone-dysregulated eating associations in 446 women who provided saliva samples for hormone measurements and ratings of NA and emotional eating daily for 45 consecutive days. Women were at greatest risk for emotional eating when they had high trait NA and experienced a hormonal milieu characterized by low estradiol or high progesterone. While effects were significant in all women, the combination of high trait NA and high progesterone was particularly risky for women with a history of clinically significant binge eating episodes. These findings provide initial evidence that affective and hormonal risk interact to promote dysregulated eating, and that effects may be amplified in women with clinically significant binge eating.Low emotion differentiation (the tendency to experience vague affective states rather than discrete emotions) is associated with psychopathology marked by emotion regulation deficits and impulsive/maladaptive behavior. However, research examining associations between emotion differentiation and dysregulated eating is still nascent. In the second study, I therefore examined associations between several measures of emotion differentiation and binge eating phenotypes across a spectrum of severity.
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Title: Effects of temperature and photoperiod on host-parasitoid synchrony and evaluation of sampling methods for Oobius agrili, an introduced egg parasitoid of emerald ash borer
Creator: Petrice, Toby R.
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Emerald ash borer (EAB), Agrilus planipennis (Fairmaire) (Coleoptera: Buprestidae) is one of the most destructive forest insect pests to be introduced into North America. Oobius agrili Zhang and Huang (Hymenoptera: Encyrtidae) is an EAB egg parasitoid native to northeastern China. EAB has spread to most of eastern North America and O. agrili has been released throughout most of this distribution. Both species now occur well beyond their endemic climatic ranges. Furthermore, photoperiod...
Show moreEmerald ash borer (EAB), Agrilus planipennis (Fairmaire) (Coleoptera: Buprestidae) is one of the most destructive forest insect pests to be introduced into North America. Oobius agrili Zhang and Huang (Hymenoptera: Encyrtidae) is an EAB egg parasitoid native to northeastern China. EAB has spread to most of eastern North America and O. agrili has been released throughout most of this distribution. Both species now occur well beyond their endemic climatic ranges. Furthermore, photoperiod modulates O. agrili diapause. Therefore, host-parasitoid synchrony could be affected in novel climatic distributions. Studies were conducted to determine the O. agrili life stages that respond to photoperiod and the critical day length for diapause induction. Results demonstrated that photoperiod induced diapause is modulated in the developing larvae and critical day length for diapause induction is between 14.25 and 14.5 hours of day light. Next. a temperature driven multiple cohort rate summation model was developed to simulate the phenology of O. agrili and EAB. Critical day length was integrated into the model to predict interactions of photoperiod and temperature regimes on host-parasitoid synchrony. The model was validated with O agrili and EAB trapping from Michigan sites. Model predictions compared with trapping data demonstrated that O. agrili has primarily two generations per year in south central and northwestern Michigan, and O. agrili enters diapause before critical day length occurs in south central Michigan. According to simulations, spatiotemporal variation in temperature regimes does not affect O. agrili-EAB synchrony, with the exception of some northern locations. However, the effect of spatial variation in day length is still unclear and dependent on how O. agrili measures day length in the field. Finally, sampling methods, sample size and seasonal timing for detecting and monitoring O. agrili in the field were evaluated. Yellow pan traps and bark sifting for parasitized eggs were more effective at recovering O. agrili compared to sentinel EAB eggs in screened pouches and bark rearing for adults. A minimum of ten yellow pan trap or bark sifting samples should be taken from each site. Yellow pan trap sampling should be conducted between 400-1200 DD10. Results of this project provide insight and tools for evaluating O. agrili phenology and spatiotemporal synchrony with EAB oviposition, determining optimal release times, and detecting and monitoring its efficacy across its current and potential distribution in North America.
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Title: Gaining a better understanding of teacher absenteeism
Creator: Gardner, Jacqueline A.
Date: 2020
Collection: Electronic Theses & Dissertations
Description: This study explores the reasons for chronic teacher absenteeism, which is a growing concern in Michigan schools and districts because teacher absenteeism is expensive and has implications for student learning. In total, 21 elementary teachers from seven different Michigan school districts were interviewed about their experiences with and perceptions of teacher absenteeism. Using an interpretive lens from the management literature on employee absenteeism, this study finds chronically absent...
Show moreThis study explores the reasons for chronic teacher absenteeism, which is a growing concern in Michigan schools and districts because teacher absenteeism is expensive and has implications for student learning. In total, 21 elementary teachers from seven different Michigan school districts were interviewed about their experiences with and perceptions of teacher absenteeism. Using an interpretive lens from the management literature on employee absenteeism, this study finds chronically absent teachers used paid time off for job-related mental health more often than for personal reasons compared to non-chronically absent teachers. The contributors to job-related mental health include three elusive, intangible characteristics: job stress, low perceived organizational support, and job dissatisfaction. The sources of job stress, low perceived organizational support, and job dissatisfaction are negative student behaviors, large class sizes, accountability pressures, lack of building support, lack of administration support, increased workload, performing additional duties above and beyond teaching, and not having enough district financial support for classroom materials and resources. The findings suggest organizational factors, or challenges with school and district culture and climate, contribute to chronic teacher absenteeism and must be improved upon. Implications for research, policy, and practice are discussed, along with opportunities for future research on both chronic teacher absenteeism and the culture and climate of schools and districts.
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Title: From land to stream : an assessment of watershed-scale biogeochemical interactions at the stream-groundwater interface
Creator: Lee-Cullin, Joseph Albert
Date: 2020
Collection: Electronic Theses & Dissertations
Description: The stream-groundwater interface (SGI) is typically studied at scales <1000 m, whereas watershed management needs to understand outcomes of stream-groundwater interactions at scales of tens of kilometers. As a ubiquitous reactive ecotone, the SGI plays a critical role in biogeochemical cycling across stream networks. Process-based models have examined these needed larger scales, but there is a distinct absence of field data to validate modeling efforts. Due to the paucity of these data, this...
Show moreThe stream-groundwater interface (SGI) is typically studied at scales <1000 m, whereas watershed management needs to understand outcomes of stream-groundwater interactions at scales of tens of kilometers. As a ubiquitous reactive ecotone, the SGI plays a critical role in biogeochemical cycling across stream networks. Process-based models have examined these needed larger scales, but there is a distinct absence of field data to validate modeling efforts. Due to the paucity of these data, this dissertation sets out to be among the first efforts to sample across the SGI at the watershed scale. The three primary goals are to 1) identify the grain of measurements needed to assess the SGI across a stream network, 2) determine whether landscape biogeochemical signals are modified by the SGI at the watershed scale, and finally 3) to investigate whether the SGI acts consistently to modify biogeochemical inputs from the landscape. This work was done through the lens of common solutes found in streams, specifically focusing on dissolved organic carbon, an important driver of many stream biogeochemical reactions. In Chapter 1, I evaluate how to sample the SGI across a stream network. I test two fundamental sampling schemes, focusing on local heterogeneity (i.e., features or plots) compared to longitudinal heterogeneity (i.e., stream reaches). There was previously no clear guidance as to which kind of sampling scheme would be most appropriate. This was necessary because sampling in the SGI is time and labor consuming, and one must determine how to distribute a finite number of sampling points. These data were collected in two synoptic sampling campaigns in a third-order stream network in southwest Michigan. Here, I found that longitudinal sampling accounted for similar stream network variance as localized heterogeneity. Therefore, it may be useful to focus on longitudinal sampling as local sampling becomes redundant.In Chapters 2 and 3, I investigate, first, how different watershed delineations are used to understand landscape contributions to the biogeochemical signal of the stream water. I compared surface watershed and novel groundwatershed delineations to evaluate which areal delineation of the landscape would best predict stream biogeochemistry. Both delineations were then used to investigate how the biogeochemical signal propagated from the land into the SGI, and whether this signal was modified as it entered the SGI by way of spatially lagged linear models. I found that both watersheds were comparable, and therefore the groundwatersheds may be appropriate for lowland watersheds, with strongly upwelling groundwater. Further, I found that the landscape signal found in surface waters through linear modeling was modified as models were propagated into the SGI, given the decreasing performance of linear models in the stream subsurface.In Chapter 4, I evaluated the SGI effects from multiple watersheds on various sources of dissolved organic carbon and its molecular components. I used mixed-effects linear models to test if there was a consistent modification of dissolved organic carbon across a multitude of SGIs as compared to stream water alone. I found that for most optical properties tested, the interaction between the specific carbon source and the SGI sediments was important, functionally obscuring the effects of the sediment alone. The one exception to this was a proxy for humic substances called Peak T, for which the SGI sediment had a significant, identifiable effect. These results indicate that it may be difficult to make broad generalizations about the function of SGIs, where local heterogeneity might be an important consideration.
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Title: Influence of landscape composition, landscape diversity, and conservation management on bee health via a pollen nutrition mechanism
Creator: Quinlan, Gabriela Marie
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Bees are the most important pollinators in agricultural systems, with honey bees (Apis mellifera L.) in particular providing the majority of pollination services on commercial farms. However, due to interacting stressors including lack of nutrition and disease, honey bees and other bee species are experiencing elevated loss rates compared to historical records. Access to abundant, high quality, continuous nutrition in the landscape has been suggested as a means of promoting bee health. To...
Show moreBees are the most important pollinators in agricultural systems, with honey bees (Apis mellifera L.) in particular providing the majority of pollination services on commercial farms. However, due to interacting stressors including lack of nutrition and disease, honey bees and other bee species are experiencing elevated loss rates compared to historical records. Access to abundant, high quality, continuous nutrition in the landscape has been suggested as a means of promoting bee health. To test this, I studied honey bee and bumble bee colonies in 12 apiaries that ranged in land cover composition of the surrounding forage landscape. Honey bee colony cluster size and brood area at the end of the summer were most closely related to post-spring pollination colony size and other colony-level variation, whereas bumble bee colony weight, gyne and drone production were related to surrounding land covers. This demonstrates the importance of accounting for potentially confounding honey bee colony variation in landscape-scale studies. To determine if diversity of land covers affected honey bee pollen foraging and colony size, I also measured honey bee colony size and incoming pollen at 12 apiaries located within landscapes of differing land cover diversity, and found that the relationship between land cover diversity, incoming pollen quantity and colony cluster size changed over time. This suggests that land cover diversity alone is insufficient for predicting patterns in honey bee landscape nutrition studies in this region. Conservation Reserve Program (CRP) land may include flowering, herbaceous species in seed mixes, but in states such as Michigan with abundant forage in unmanaged habitats, it is unclear if CRP investments have unique floral composition, and foraging by honey bees and wild bees. I assessed floral composition and bee visitation on CRP land as compared to analogous unmanaged fields and roadside ditches in 31 triplicate sites. Floral abundance, species richness, native flower abundance, and inflorescence coverage were all higher on CRP land, as were honey bee and wild bee visitation, indicating that herbaceous CRP promotes bee foraging through unique floral composition, namely floral density. By assessing the quantity and quality of incoming pollen at apiaries while concurrently surveying floral communities in nearby grassy-herbaceous forage habitat, I found that crude protein in collected pollen decreased throughout the summer, concurrent with decreasing floral richness and abundance. This suggests pollinator plantings should include protein-rich, late-blooming species in their seed mixes. Because nutrition is closely tied to disease in honey bees, supplementing protein may promote recovery from diseases such as European foulbrood. To compare different approaches to managing this disease, European foulbrood-infected colonies were treated with traditional antibiotics, antibiotics with a soy-based protein supplements, soy-based supplement alone, pollen-based supplement, probiotics, or left untreated. There was no significant difference among non-antibiotic treatments in post-treatment recovery speed or nurse bee physiology, suggesting these supplemental feeding treatments and probiotics provide no treatment benefits for European foulbrood. Based on this research, accounting for colony-level variation is essential in honey bee landscape studies. Adding pollinator conservation habitat with an increased emphasis on late-season, protein-rich pollen species in seed mixes can benefit honey bees and wild bee species. This work provides new insights into the effects of landscapes on honey bee and wild bee foraging, nutrition and health by examining different aspects of these indirect relationships.
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Title: A critical review of Michigan's spring waterfowl survey
Creator: Yost, Nathaniel Thomas
Date: 2020
Collection: Electronic Theses & Dissertations
Description: To monitor the status of waterfowl populations, the Michigan Department of Natural Resources (MDNR) began surveying abundance of breeding ducks and geese in 1991 and developed goals for waterfowl population and habitat management tied to the spring waterfowl survey. The spring waterfowl survey required flying a series of fixed-width transects using fixed-wing aircraft to estimate statewide abundance of Canada geese (Branta canadensis), mallards (Anas platyrhynchos), mute swans (Cygnus olor),...
Show moreTo monitor the status of waterfowl populations, the Michigan Department of Natural Resources (MDNR) began surveying abundance of breeding ducks and geese in 1991 and developed goals for waterfowl population and habitat management tied to the spring waterfowl survey. The spring waterfowl survey required flying a series of fixed-width transects using fixed-wing aircraft to estimate statewide abundance of Canada geese (Branta canadensis), mallards (Anas platyrhynchos), mute swans (Cygnus olor), and sandhill cranes (Grus canadensis) among others. To get consistent results, standard operating procedures (SOP) have been implemented and maintained across the years. Since observers did not see all birds from the fixed-wing aircraft, estimation of waterfowl abundance required surveying a portion of transects with helicopters to establish visibility correction factors (VCF). MDNR used the VCF to adjust fixed-wing estimates assuming observers saw all birds in transects flown with helicopters. To potentially improve precision and reduce costs, we developed alternate VCFs and aerial survey designs to understand how the accuracy and precision of the waterfowl population estimate changed from the existing SOP methodology. To meet MDNR standards, we considered alternate population estimates that produced a coefficient of variation (CV) of less than 20% to be acceptable and worth consideration. We found comparable population estimates and CVs from eleven alternate VCFs and three alternate aerial survey designs compared to the SOP.
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Title: American woodcock habitat selection and reproductive success in Michigan
Creator: Huinker, Ashley Elizabeth
Date: 2020
Collection: Electronic Theses & Dissertations
Description: A detailed abstract with results is included at the beginning of each chapter as they are intended for separate publication. In chapter one, I evaluated how habitat selection for American woodcock (Scolopax minor) nests and broods is affected by local vegetation characteristics. I also assessed changes in earthworm density, an important food source for woodcock, over the course of the breeding season. I hypothesized that habitat selection would be different between nesting and brood-rearing...
Show moreA detailed abstract with results is included at the beginning of each chapter as they are intended for separate publication. In chapter one, I evaluated how habitat selection for American woodcock (Scolopax minor) nests and broods is affected by local vegetation characteristics. I also assessed changes in earthworm density, an important food source for woodcock, over the course of the breeding season. I hypothesized that habitat selection would be different between nesting and brood-rearing hens, that selection cues would change throughout the breeding season as chicks aged, and that earthworm density would decline throughout the breeding season. I deployed cameras to woodcock nesting sites, captured and marked woodcock broods with telemetry equipment, and measured vegetation around both used and available sites. My results showed that nesting woodcock select different habitat than do brood-rearing birds and that earthworm density in the top layers of soil declines throughout the breeding season, but brood habitat selection did not change as chicks aged.In chapter 2, I linked nest success and brood survival to local habitat characteristics. I hypothesized that stem density, canopy cover, soil moisture, and soil organic matter would have positive effects on reproductive success. Using Mayfield and known fate analysis methods, I estimated nest success and brood survival from hatch to fledge. My results showed that nest success was not influenced by local habitat characteristics, but that brood survival was influenced by woody ground cover, such as shrubs and seedlings, and soil moisture. My results indicate that understory cover is an important consideration for woodcock habitat management.
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Title: Adsorption media for the removal of phosphorus in subsurface drainage for Michigan corn fields
Creator: Hauda, Jessica Kathleen
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Phosphorus is a valuable, non-renewable resource in agriculture promoting crop growth. and is used in the global food chain, mainly as fertilizer. Soluble phosphorus plays a part in the eutrophication in freshwater environments, which impacts tourism, human health, environmental safety, and property values. Phosphorus loss from agricultural land is also a loss of investment that went into keeping it on the soil, and its addition into water bodies can increase costs to manage the affected area...
Show morePhosphorus is a valuable, non-renewable resource in agriculture promoting crop growth. and is used in the global food chain, mainly as fertilizer. Soluble phosphorus plays a part in the eutrophication in freshwater environments, which impacts tourism, human health, environmental safety, and property values. Phosphorus loss from agricultural land is also a loss of investment that went into keeping it on the soil, and its addition into water bodies can increase costs to manage the affected area(s). This research entails selecting the phosphorus adsorption media best suited for removing phosphorus from subsurface drainage in Michigan farms. Selected adsorption media from the literature includes engineered nanomaterials, biochar, and natural materials. These media were evaluated with typical subsurface drainage phosphorus concentrations using batch adsorption and column experiments to verify if the media worked in this application. Both the steel furnace slag (SFS) and PO4Sponge removed soluble reactive phosphorus from 0.500 to below 0.05 mg/L in column experiments at an empty bed contact time of 5-minutes The SFS was the most cost-effective option based on a case-study and generalized analysis. The most expensive option was the use of PO4Sponge media to remove phosphorus, then regenerating it at the manufacturer.
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Title: Impact of biomimetic window system on building energy consumption and occupants' perception in the educational environment
Creator: Son, Juntae
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Although people are spending more time indoors, their perception of the indoor environment is not improved; meanwhile, building energy consumption continues to rise. About 40 percent of all U.S. energy was consumed by residential and commercial sectors whereas educational buildings consumed 11 percent and 13 percent of total electricity and natural gas consumption, respectively. These days, extensive studies have sought to reduce building energy consumption through various mechanical methods....
Show moreAlthough people are spending more time indoors, their perception of the indoor environment is not improved; meanwhile, building energy consumption continues to rise. About 40 percent of all U.S. energy was consumed by residential and commercial sectors whereas educational buildings consumed 11 percent and 13 percent of total electricity and natural gas consumption, respectively. These days, extensive studies have sought to reduce building energy consumption through various mechanical methods. However, these methods focus exclusively on building energy. Therefore, other methods need to be proposed to enhance the perception of the building occupants.The purpose of this study was to examine the enhancement of energy consumption and occupants' perception by using strategies that adopt the characteristics of nature, called biomimetic design. In this study, the biomimetic solutions were designed to bring daylight into an interior space in educational buildings, where daylight generally cannot reach. Specifically, this study investigated how the daylight achieved through biomimetic windows affected building energy consumption and students' perceptions in educational spaces. Therefore, this study looked for biomimetic approaches that could bring more daylight into the interior space and determined that such approaches changed the energy consumption and perception of occupants in the educational building.This study investigated the positive effects of daylight on people and found a strategy from biomimicry methods. This study proposed a new biomimetic window system based on the fur of polar bears, which reflects daylight. This research had two research phases. Through computer simulations, this study examined how the new biomimetic window system saved building energy consumption. This study created a 3D model which is the currently existing MSU main library and compared its energy consumption and actual energy consumption. Using the created 3D model, this study conducted simulations only for the basement floor, which does not have windows. When the simulations were conducted with the basement floor, about 13 percent of energy was saved from the installation of a biomimetic window system. The second phase of the study was to collect occupants' perceptions in virtual reality spaces with biomimetic windows using an experimental research approach. Three major findings need to be highlighted. First, students were more satisfied with an area where daylight entered through the biomimetic window system than the one without a window. Second, when the biomimetic window system was installed, students preferred an enclosed space over an open space. Third, their seating preference depending on the average study time of students did not vary much whether there is the biomimetic window system. However, there was weak relationship between students' average study time and their perception with spaces.Using a biomimetic solution to utilize daylight, this study found practical ways to reduce building energy consumptions for indoor lighting by using actual daylight. Using this nature-inspired new method, this study proposed a way to reduce energy consumption in educational buildings while simultaneously improving occupants' perception and satisfaction. The results of this study will be a milestone for developing a biomimetic window system and helping energy saving in the educational building environment while improving occupants' perceptions therein.
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Title: Early-life exposures and their impact on gut microbiota assembly : a longitudinal analysis of the infant gut microbiota in Michigan cohorts
Creator: Sugino, Kameron
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Background: Obesity is a global epidemic and is responsible for increasing burdens on public health. Factors like diet and lifestyle have been investigated as modifiable factors that can help prevent the development of obesity, but another possible mediator of obesity development is the gut microbiome. The gut contains a diverse community of microbes that influences several physiological functions in humans and animals. There have been many studies investigating this association between...
Show moreBackground: Obesity is a global epidemic and is responsible for increasing burdens on public health. Factors like diet and lifestyle have been investigated as modifiable factors that can help prevent the development of obesity, but another possible mediator of obesity development is the gut microbiome. The gut contains a diverse community of microbes that influences several physiological functions in humans and animals. There have been many studies investigating this association between obesity and the microbiota in adults, however, few studies have been done on the establishment of the infant gut microbiota in the context of its association with maternal pre-pregnancy body mass index (BMI), breastfeeding and delivery mode. Hypothesis: We expect maternal pre-pregnancy BMI will be associated with altered microbiota composition of women and their children. However, in children, this association will have less of an effect on the gut microbiota than exposure to human milk in the diet.Methods: Fecal samples and participant information were collected from a subset of dyads enrolled in two related prospective cohorts (ARCHGUT and BABYGUT) in Michigan. Sequencing the V4 region of the 16S gene was used to analyze fecal bacterial samples collected from mothers in their third trimester and infants at 1, 6, 12 and 24 months of age. The microbiota data was analyzed using alpha and beta diversity metrics, negative binomial regression to compare taxa abundances between groups and LonGP, a microbiota analysis tool for longitudinal data sets. Results: We found that fecal bacterial communities from overweight women had lower microbiota diversity than communities from normal weight or obese women and beta diversity of overweight women differed from those of normal and obese women at the genus and phylum levels. Infant alpha diversity at 1 month of age differed in membership (Sorensen index) by maternal pre-pregnancy BMI category and also differed by delivery mode and breastfeeding exclusivity. At 6 months of age, fewer infants born to women with pre-pregnancy obesity were breastfeeding compared to infants born to non-obese women (35.7% and 81.8%, respectively). Maternal pre-pregnancy BMI and human milk exposure were both significantly associated with alpha and beta diversity of the infant microbiota in univariate analyses. However, in multivariate analyses, human milk exposure accounted for 20% of variation in alpha diversity, but pre-pregnancy BMI was not significantly associated with microbiota diversity. The infant diet at six months was the major determinant of alpha and beta diversity of the infant. In our longitudinal analysis of the infant fecal microbiota from 1 month to 2 years of age, we found that age and participant explained most of the changes in abundance in our dataset. In the top 10 most abundant taxa, human milk exposure and antibiotic exposure at the time of sampling were the only variables important besides age and ID, specifically for Lachnospiraceae unclassified and Bacteroides abundances. Lachnospiraceae abundance was much higher as infants aged, in infants receiving 30.Conclusion: Here, we found several associations between the infant gut microbiota and infant exposures during the first two years of life. Exploring the relationship between gut health and early infant exposures could help develop potential preventative treatments for many gut-linked chronic diseases such as obesity.
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Title: Three essays on the economics of education
Creator: Acton, Riley K.
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Chapter 1: Effects of Reduced Community College Tuition on College Choices and Degree Completion. Recent efforts to increase college access concentrate on reducing tuition rates at community colleges, but researchers and policymakers alike have expressed concern that such reductions may not lead to long-run college completion gains. In this chapter, I use detailed data on students' college enrollment and completion outcomes to study how community college tuition rates affect students'...
Show moreChapter 1: Effects of Reduced Community College Tuition on College Choices and Degree Completion. Recent efforts to increase college access concentrate on reducing tuition rates at community colleges, but researchers and policymakers alike have expressed concern that such reductions may not lead to long-run college completion gains. In this chapter, I use detailed data on students' college enrollment and completion outcomes to study how community college tuition rates affect students' outcomes across both public and private colleges. By exploiting spatial variation in tuition rates, I find that reducing tuition at a student's local community college by $1,000 increases enrollment at the college by 3.5 percentage points (18%) and reduces enrollment at non-local community colleges, for-profit institutions, and other private, vocationally-focused colleges, by 1.9 percentage points (15%). This shift in enrollment choices increases students' persistence in college, the number of credits they complete, and the probability that they transfer to and earn bachelor's degrees from four-year colleges. Chapter 2: Community College Program Choices in the Wake of Local Job Losses. Deciding which field to study is one of the most consequential decisions college students make, but most research on the topic focuses on students attending four-year colleges. In this chapter, I study the extent to which community college students' program choices respond to changes in local labor market conditions in related occupations. To do so, I exploit the prevalence of mass layoffs and plant closings across counties, industries, and time, and create occupation-specific layoff measures that align closely with community college programs. I find that declines in local employment deter students from entering closely related community college programs and instead induce them to enroll in other vocationally-oriented programs. Using data on occupational skill composition, I document that students predominantly shift enrollment between programs that require similar skills. These effects are strongest when layoffs occur in business, health, and law enforcement occupations, as well as when they take place in rural counties. Chapter 3: Do Health Insurance Mandates Spillover to Education? Evidence from Michigan's Autism Insurance Mandate (with Scott Imberman and Michael Lovenheim). Social programs and mandates are usually studied in isolation, but interaction effects could create spillovers to other public goods. In this paper, we examine how health insurance coverage affects the education of students with Autism Spectrum Disorder (ASD) in the context of state-mandated private therapy coverage. Since Medicaid benefits under the mandate were far weaker than under private insurance, we proxy for Medicaid ineligibility and estimate effects via triple-differences. We find little evidence of an overall shift in ASD identification, but we do find substantial crowd-out of special education services for students with ASD from the mandate. The mandate led to increased mainstreaming of students in general education classrooms and a reduction in special education support services like teacher consultants. There is little evidence of changes in achievement, which supports our interpretation of the service reductions as crowd-out.
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Title: Horseweed growth types and integrating fall-planted cereal cover crops for management
Creator: Schramski, John Allen
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Recent shifts in glyphosate-resistant horseweed (Erigeron canadensis L.) emergence patterns and growth types at the field level have generated new management questions. Field experiments investigated the effects of cereal rye and winter wheat, seeded at 67 or 135 kg ha-1, in combination with burndown herbicide strategies or terminated at different times for managing horseweed in no-tillage soybean. In absence of effective herbicides, fall-planted cereal cover crops reduced horseweed biomass...
Show moreRecent shifts in glyphosate-resistant horseweed (Erigeron canadensis L.) emergence patterns and growth types at the field level have generated new management questions. Field experiments investigated the effects of cereal rye and winter wheat, seeded at 67 or 135 kg ha-1, in combination with burndown herbicide strategies or terminated at different times for managing horseweed in no-tillage soybean. In absence of effective herbicides, fall-planted cereal cover crops reduced horseweed biomass up to 70 and 33% at cover termination and five weeks after soybean planting, respectively. Integrating effective herbicide strategies improved horseweed suppression and soybean yield. Delaying termination by Planting Green improved horseweed suppression through the time of postemergence application. Additional field experiments evaluated the effects of termination timing and herbicide combinations for cereal rye termination. Glyphosate applied at 1,267 g ae ha-1 to cereal rye at early (Feekes 6) or late (Feekes 10.5) growth stages effectively terminated cereal rye. The addition of dicamba to glyphosate applied late, or clethodim alone provided less control. All herbicide combinations tested, with the exception of those which included metribuzin, provided similar control to glyphosate alone. In controlled environment experiments, a vernalization period following imbibition of water, but prior to germination, induced horseweed bolting at emergence. Additionally, bolted type horseweed in glyphosate-resistant populations was less sensitive to glyphosate than rosette type. This research provides growers strategies for managing horseweed and insight into the recent glyphosate-resistant horseweed emergence and growth type phenomena observed in the field.
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Title: Biology and management of leafhoppers and aster yellows phytoplasma in Michigan celery and carrot agroecosystems
Creator: Stillson, Patrick T.
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Managing aster yellows phytoplasma (Candidatus Phytoplasma sp.) and its leafhopper vectors is complex and requires better control methods than those currently used and a greater understanding of the phytoplasma-insect relationship. In this thesis, I determine the effectiveness of a decision support tool focused on managing phytoplasma infected leafhoppers and determine whether leafhoppers in celery and carrot field edges contribute to phytoplasma transmission within the crop fields.We...
Show moreManaging aster yellows phytoplasma (Candidatus Phytoplasma sp.) and its leafhopper vectors is complex and requires better control methods than those currently used and a greater understanding of the phytoplasma-insect relationship. In this thesis, I determine the effectiveness of a decision support tool focused on managing phytoplasma infected leafhoppers and determine whether leafhoppers in celery and carrot field edges contribute to phytoplasma transmission within the crop fields.We informed farmers about phytoplasma infectivity on their farms via a web-based text messaging system to shift county-level management of Macrosteles quadrilineatus from using leafhopper abundance to infectivity. We found that infected M. quadrilineatus abundance decreased after farmers were informed about their numbers, suggesting that our decision support tool allowed growers to successfully manage infected M. quadrilineatus. We also identified temporal differences in infected and uninfected leafhopper peak abundance in celery but not in carrot cropping systems, suggesting that farmers should account for these phenological shifts across crops and over time.In the field edge surveys, leafhoppers were collected from celery and carrot fields and field edges. I identified leafhoppers through DNA barcoding and conducted real-time PCR to determine phytoplasma infection status. The most abundant species were M. quadrilineatus (57%) and Empoasca fabae (23%). Our results confirmed that M. quadrilineatus was the primary vector in celery and carrots, although there is evidence that E. fabae may also vector this pathogen.
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Title: Testing the reminding account of the lag effect in L2 vocabulary acquisition from L2-L1 retrieval practice within a paired-associate learning format
Creator: Koval, Natalya G.
Date: 2020
Collection: Electronic Theses & Dissertations
Description: The spacing/lag effect refers to the finding in memory research that spacing repeated study more widely produces important learning benefits (Crowder, 1976; Dempster, 1988, 1989). In order to know when and how this effect can be most useful for second language learning, it is important to understand the cognitive mechanism(s) that drive any effects of spacing in second language learning. It is also important to understand how the operation of the mechanism(s) may be affected by variables...
Show moreThe spacing/lag effect refers to the finding in memory research that spacing repeated study more widely produces important learning benefits (Crowder, 1976; Dempster, 1988, 1989). In order to know when and how this effect can be most useful for second language learning, it is important to understand the cognitive mechanism(s) that drive any effects of spacing in second language learning. It is also important to understand how the operation of the mechanism(s) may be affected by variables inherent in second language learning contexts. In the present study, I investigate the contribution of the dual mechanism of effortful successful retrieval to the effects of lag in second language vocabulary learning. This dual mechanism is proposed to underlie both beneficial and detrimental effects of lag on learning within the reminding account (Benjamin & Tullis, 2010). I additionally investigate the potential effects of externally imposed study time on learning as well as on the operation of the two mechanisms under investigation.Fifty-two native speakers of American English studied 72 novel L2 Finnish words during overt oral L2-L1 translation retrieval practice in a paired-associate learning format from 6 repetitions under three constant levels of within-session lag with immediate study of feedback for 3 or 9 seconds after each retrieval attempt. Study-phase response latencies and accuracy were recorded and used as measures of study-phase retrieval effort and success, respectively (as in Maddox & Balota, 2015). Immediate and delayed form recognition, L2-L1 translation and translation matching posttests were used to measure learning outcomes.Results showed a large spacing effect on all measures and at both times of test administration as well as a lag effect on delayed meaning tests. A nonsignificant nonmonotonic function was observed only on immediate posttests. Study time had an overall small positive effect on learning; however, it did not cancel out negative effects of massing retrieval practice: the effects of spacing were considerably larger. Increasing lag between retrieval attempts produced increasingly longer study-phase response latencies and increasingly lower levels of study-phase retrieval success. Study time had a small nonsignificant negative effect on study-phase response latencies and a small significant positive effect on study-phase retrieval success. Moderated mediation analyses showed that study time, as operationalized in the present study, did not affect the operation of the two underlying mechanisms under investigation. They further showed that, despite the fact that a nonmonotonic function was not observed in the present learning outcomes, increasing inter-study interval still had a negative effect on learning and this effect operated through a lower rate of study-phase retrieval success. Further, the moderated mediation analyses showed that the positive effects of retrieval effort (Roediger & Karpicke, 2006) were conditional on retrieval success, in line with predictions of the reminding account.The findings of the dissertation suggest that: (a) massed L2-L1 translation retrieval practice may not be effective for L2 vocabulary learning; (b) externally imposing a longer study time does not have the large benefits that learner-regulated longer study time does; (c) effortful successful retrieval underlies benefits of lag in L2 vocabulary learning from L2-L1 retrieval practice-the benefits of effortful retrieval are conditional on retrieval success, even in the presence of immediate feedback; (d) successful retrieval is more beneficial than unsuccessful retrieval, even when retrieval attempts are followed by immediate feedback - study of feedback does not offset the negative effects of retrieval failure.
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Title: Toward better management of spotted-wing drosophila (Drosophila suzukii) in Michigan cherry orchards
Creator: Dietrich, Sarah R.
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Spotted-wing drosophila, Drosophila suzukii Matsumura (Diptera: Drosophilidae), is an invasive species that has impacts worldwide. Current monitoring methods and decision-making protocols are unreliable indicators of D. suzukii population and propensity to infest a crop. The aim of this research was to develop behavior-based tools that would lead to improved management of D. suzukii populations in Michigan cherry. The commercial Scentry® lure provided higher D. suzukii attractiveness than...
Show moreSpotted-wing drosophila, Drosophila suzukii Matsumura (Diptera: Drosophilidae), is an invasive species that has impacts worldwide. Current monitoring methods and decision-making protocols are unreliable indicators of D. suzukii population and propensity to infest a crop. The aim of this research was to develop behavior-based tools that would lead to improved management of D. suzukii populations in Michigan cherry. The commercial Scentry® lure provided higher D. suzukii attractiveness than other commercially available lures. Sticky panels tested with a variety of colors and patterns showed that most D. suzukii are captured on a green panel or a light-colored panel with a dark contrasting sphere in the center, as well as panel traps with a large trap surface are. Studies aimed at understanding the relationships between fruit development and D. suzukii infestation revealed that over all the varieties of sweet and tart cherries tested, softer, riper fruit were more susceptible to infestation than unripe fruit. There were strong positive relationships between D. suzukii larval infestation and the change in color and the change in the amount of force required to puncture the skin of the cherry fruit. There also was a good relationship between Growing Degree Days (base 4°C) post bloom and larval infestation, with fruit at a low risk of infestation by D. suzukii prior to about 600 GDD's. This research provides information on creating a risk of infestation model that uses fruit ripeness stage based on Growing Degree Days, combined with effective monitoring tools, to provide options for improved decision-making in the management of D. suzukii.
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