ScholarWorks@UMassAmherst
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Publication Relationship-centered engagement bridges the divide between science and management, and enhances climate adaptation(Oxford University Press, 2025)The rapid pace of climate change demands changes in management practices. Despite abundant climate adaptation research, the implementation of climate adaptation can lag in the management space. In the present article, we argue that relationship-centered engagement—establishing and maintaining relationships among researchers and natural resource managers—is critical for bridging the research–management gap. We evaluated researcher–manager partnerships within the US Northeast Climate Adaptation Science Center and identified three cultural shifts that institutions, funders, researchers, and managers could adopt to boost the odds of trans- lating findings into action: acknowledging and supporting the central role of relationships in creating and implementing actionable science, lengthening funding timelines to better support establishing and maintaining relationships, and aligning institutional rewards to support relationship building. A renewed focus on relationships can lead to more diverse and effective partnerships that bridge knowledge to practice and hasten adaptation to climate change.Publication Formate and hydrogen metabolism in the hyperthermophile Thermococcus and their application in waste-to-hydrogen conversion(2025-05)Fossil fuel-driven climate change is worsening at an alarming rate with energy demands expected to keep rising in the coming decades. Hence, novel sustainable energy technologies are needed to curb climate change and meet growing energy needs. Hydrogen (H2) energy is expected to increase and complement renewable electricity as production, storage, and transportation technologies are drastically improving, playing a critical role in decarbonizing the world. Therefore, there is growing interest in biohydrogen (bioH2) – the production of H2 using microorganisms. This dissertation explores H2 metabolism enzymes of organisms in the genus Thermococcus and studies the link between formate and H2 metabolism to optimize bioH2 production using waste as a substrate. Thermococci are hyperthermophilic archaea that are commonly found in hydrothermal vents. They are obligate heterotrophs and perform either sulfur- or proton-based respiration. A literature and genome survey of thirty Thermococcus species found that all species encoded for at least one membrane-bound hydrogenase (mbh) operon and all but one encoded for a soluble sulfhydrogenase (sh). The two operons formed the core hydrogenases of Thermococci. All surveyed species also encoded for a formate dehydrogenase catalytic subunit (fdhA) or fdhA-containing operon in the form of formate hydrogenlyase (fhl) or NAD(P)+-dependent formate dehydrogenase (nfd). Fhl-encoding Thermococci likely produce formate from H2 and CO2 in a reversible reaction when H2 concentrations become inhibitory. Formate production and utilization was only observed in species encoding a formate transporter. Formate concentration in hydrothermal vents is highly dependent on H2 concentration; vent sites with high formate concentrations also contain more H2. While there is a strong link between H2 and formate metabolism in Thermococci and in hydrothermal vents, further studies are needed to fully elucidate their physiological roles. H2 production by Thermococcus paralvinellae using brewery wastewater as a feedstock and the effect of formate on H2 production were examined. Brewery wastewater was identified as a test waste feedstock based on customer discovery through the NSF I-Corps™ program at UMass Amherst. Growth, H2 yield, and activities of hydrogenases and formate hydrogenlyase (Fhl) were determined when T. paralvinellae was grown on maltose only (model brewery wastewater), formate only, maltose plus formate, brewery wastewater only, and brewery wastewater plus formate to identify conditions for optimum H2 production. H2 yield was higher in formate-containing media compared to media without formate. However, activities of hydrogenases and formate hydrogenlyase remained largely consistent showing that formate did not affect relative enzyme abundance in the cell. Formate was identified as an additive to increase H2 production by T. paralvinellae using brewery wastewater as a feedstock. A pilot-scale 2 L bioreactor was operated in batch and chemostatic mode using brewery wastewater with and without the addition of formate. In batch mode, H2 production was higher with formate relative to without formate but dropped to levels comparable to the absence of formate by mid-logarithmic growth phase. High H2 production in the presence of formate was sustained during chemostatic growth. Proof-of concept showing that formate enhances H2 production by T. paralvinellae when grown on brewery wastewater was demonstrated. Further optimization and scale-up in needed to determine the true industrial potential of this waste-to-H2 process.Publication Extending the grazing season in New England(2025-05)Livestock farmers need diverse tools to meet the challenge posed by climate change. Four research projects explored methods for grazing season extension to improve farm resiliency. 1) Cereal rye (Secale cereal L.) and triticale (x Triticosecale Wittm. ex A. Camus.) were interseeded in existing cool-season pastures. Herbage accumulation increased by 0.5 Mg dry matter (DM) ha–1 after interseeding 135 kg ha–1 of rye and triticale. Adding 45 kg N ha–1 also increased herbage accumulation by 474 kg DM ha–1. 2) Three experiments on crabgrass (Digitaria ciliaris (Retz.) Koeler and Digitaria sanguinalis (L.) Scop.) examined varietal differences, seeding rate and timing, harvest management, and haylage quality. Crabgrass performed best grown from early summer to late summer for the best balance of herbage accumulation and nutritive value (2.70-3.95 Mg DM ha–1 and 15.0-16.0% crude protein (CP) for D. sanguinalis). D. sanguinalis was best as a one-cut forage and produced good quality silage seeded at 6.7 kg ha–1 with 56 kg N ha–1. D. ciliaris can be a productive multi-cut forage when fertilized between cuttings (3.66 Mg DM ha–1 and 18.7% CP over two harvests). 3) Six brassica cultivars were intercropped with oats and peas at various seeding rates. When vegetative brassicas were seeded at 1.7-3.4 kg ha–1 with 50-75 kg ha–1 oats and 34-50 kg ha–1 peas, they produced an average of 2620 kg DM ha–1 with 22.6% CP. Flowering mustard (Brassica juncea (L.) Czern.) performed best when seeded at 5.0 kg ha–1 in mixtures (3654 kg DM ha–1, CP: 19.7%). 4) Tall fescue (Lolium arundinaceum (Schreb.) Darbysh.), orchardgrass (Dactylis glomerata L.), and their combination were evaluated with five nitrogen treatments. Adding nitrogen fertilizer or including legumes increased herbage accumulation by 0.88-1.54 Mg DM ha–1 to a total of 2.8-4.3 Mg DM ha–1 with as much as 11.0% CP. Overall, these four cropping systems demonstrate effective strategies to extend the grazing season from early spring to late fall, improving both farm productivity and resilience in the face of climate change.Publication Examining the Influence of TIES Teacher Training on Perceptions oF Self efficacy, Self-awareness and Student-Teacher Relationships Across Racial Lines(2025-05)Teachers are facing significant burnout and attrition rates due to evolving workplace demands and the growing mental health, social-emotional and behavioral needs of students. Teachers reduced persistence and optimism have been associated with factors such as low self-efficacy, with classroom management being identified as a major source of stress impacting their well-being. Several evidence-based classroom management strategies have been identified in the literature. Yet, pre-service teacher programs and professional development training have largely neglected classroom management training opportunities, resulting in teachers feeling unprepared to address the behavioral needs of their students (Freeman et al., 2014). Similarly, teaching in a diverse classroom setting poses unique challenges that undermines teachers' confidence, affecting their ability to effectively manage classroom behaviors and establish trusting, positive relationships with students whose backgrounds are different from their own. The purpose of the current study was to examine the impact of a culturally responsive, evidence-based classroom management training (TIES) on a sample of MA teachers reported self-efficacy, self- awareness and relationships with students across racial lines. A random effects linear regression model was used to evaluate the research questions. Results suggest that TIES may have positively influenced teachers perceived self-efficacy, student-teacher interactions, and self-awareness. Furthermore, TIES was found to be both practical and effective in meeting teachers' needs. Additional research with a larger sample size and sufficient statistical power is needed to yield significant findings and allow for the generalization of results. Implications for practice and future research are discussed.
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