In the United States, the public uses 40 billion gallons of water daily (Moupin, 2015). Much of the water that is used domestically will remain in the centralized public water system and will require treatment at a wastewater treatment plant (WWTP). However, 20% of the US does not return the water directly to the centralized water system, instead utilizing onsite septic systems to treat and disperse their water (Septic Systems Fact Sheet, 2008). Disposal methods for septage, the waste pumped from the septic tanks, are more limited than wastewater disposal methods. Wastewater treatment plants often refuse septage haulers due to the variable and unknown nature of the septage contents. The septage accepted at WWTP faces the same disposal statistics as wastewater. Approximately half (45%) of wastewater is landfilled or incinerated and the other half (55%) is land applied (Shaddel et al., 2019). Each of these disposal methods poses a risk to the environment. Landfilling the septage decreases the life expectancy of the landfill site and increases the risk of polluting the soil and nearby water supplies. Incineration releases harmful gases and chemicals into the atmosphere, and land application increases the risk to human health via the movement of contamination and pollution.This study aimed to determine if treated septage is beneficial to crop growth and soil health when used as a fertilizer and irrigation source. Durum wheat was the crop that was chosen for this study. This crop was selected due to its dual-purpose uses. The seeds can be collected for seed production, and the rest of the crop can be used for fodder. Septage dispersal and treatment are regulated by the United States Environmental Protection Agency (EPA) under the same guidelines as sewage sludge and is referred to as biosolids when treated to reduce pathogen load. For this study, the septage was dewatered using a spiral filter press and then treated using a low-temperature dehumidification system to dry it to 90% total solids or higher to produce Class A septage that are then land applied. The dehumidification system operates at a temperature and time sufficient to result in Class A biosolids according to US Part 503 EPA Alternative 1 (EPA, 2018). The thermal treatment addresses the health concerns of direct land application. To reduce pathogen load, this experiment consisted of two parallel trials, each with eight treatments. Each trial included two different application rates of the Class A septage, one application of traditional chemical fertilizer, and a control that received no fertilizer treatment. These four treatments were the same across both trials. Trial 1 received canal water flood irrigation. The other half, trial 2, were flood irrigated with the filtrate removed during the dewatering stage that was aerated and treated using a bacterial blend specific to SludgeHammer, a water treatment company, and mixed with the condensate water collected during the thermal treatment process (SludgeHammer, 2023). The findings of the study show that Class A septage can be beneficially used as fertilizer to enhance plant growth and soil health. The application of the treated filtrate water, however, was found to improve plant growth but detrimentally impacted soil health. Due to elevated pathogen levels found in the soil after the experiment, using filtrate for irrigation is not recommended without further treatment. Further research is necessary to determine the optimal application rate of Class A septage and to assess the long-term effects of using septage-based fertilizers.

Near Copiapó, Chile, volcanic-dominated rocks of the Early Cretaceous Punta del Cobre Formation host Fe-oxide(-Cu-Au) (“IOCG”) mineralization with varied development of metamorphic mineral assemblages. Western occurrences, such as the Candelaria deposit, lie within the metamorphic aureole of the composite Copiapó batholith (110-120 Ma), while other, more easterly deposits in the district lack evidence of high-grade metamorphism. This allows comparison of features seen at Candelaria, but not at the other deposits, that may have resulted from contact metamorphism. Petrography and scanning electron microscopy of Candelaria samples reveal early penetrative, planar fabrics overprinted by texturally and mineralogically recrystallized assemblages. High-temperature metamorphism of iron-enriched protoliths led to the development of biotite, garnet, (Mg,Fe,Mn) amphiboles, and cordierite-bearing assemblages in the Punta del Cobre formation. Metamorphic silicates overgrowing and crosscutting deformed, recrystallized ore minerals suggests that shear-zone deformation and contact metamorphism occurred during and after mainstage Cu-sulfide and Fe-oxide deposition. Peak greenschist to amphibolite-facies contact metamorphism occurred at P<4 kbar and 730-815±50℃. New U-Pb geochronology of garnets spans 115.8±3.7 Ma to 87.5±3.7 Ma and broadly coincides with magmatism and later alteration in the district. The contact metamorphosed mineralization at Candelaria resembles nominally syn-metamorphic mineralization elsewhere in the world, supporting post-mineralization metamorphic interpretations at these other locations.

Structural failures can occur when loading conditions cause stress and strain within a material that exceeds the ultimate strength. Similarly, the performance of an optical system can be adversely affected by poorly characterized loading conditions and the resulting stress fields. Rigorous stress analysis is crucial to ensuring a specified performance can be achieved under varying environmental conditions. This work presents stress measurements and analysis for two projects: i) measurement of the stress-optic coefficient of N-Bk7, a glass commonly used for optical components, and ii) a payload design for a high-altitude ($\approx$ 30 [km]) balloon deployment of an Infrared Channeled Spectro-Polarimeter (IRCSP). The N-Bk7 stress analysis is functionally based on the relationship between stress and measured polarimetric response. Stress in optical systems induces birefringence, where the index of refraction is dependent on the polarization of the incident light. Measuring the retardance of a material can therefore help determine how the stress is affecting the index of refraction of the material. This effect is quantified by the stress optic coefficient. For this work, a Rotating Retarder Mueller Matrix Imaging Polarimeter (RRMIP) was used to measure the linear retardance of a diametrically loaded sample of N-Bk7 at a wavelength of 1550 [nm]. These retardance measurements were used to compute the N-Bk7 stress optic coefficient as compared to industry-reported values. Prior to the 2021 deployment of IRCSP on a high-altitude balloon, a fully autonomous system was developed to control the image acquisition, focal plane temperature, and humidity of the instrument. Operating this optical system at high altitudes required analysis of the varying environmental conditions to design an instrument enclosure that met both optical and safety specifications. Finite Element Analysis (FEA) was used to show efficacy of the mechanical design under expected flight loads to earn flight approval from Columbia Scientific Balloon Facility (CSBF). This enclosure has been apart of three successful balloon deployments of IRCSP. Additional work to design the electronics for a PID-controlled thermo-electric cooler in also included.

Herding in the Ladakh region is a common yet dwindling practice as Ladakh faces changing political and socio-economic conditions. In the Changthang region of Ladakh, Changpa (Ladakhi) and Tibetan refugee pastoralists continue to practice herding and support their livelihood. However, in the last few decades, they are facing compound challenges to sustaining their traditional herding livelihoods due to urbanization, youth migration, and generational change. In this study, I look at how Tibetan refugee pastoralists in Changthang Samed (out of nine different locations) perceive climate change and its impact on their livelihood. Tibetan refugee pastoralists relocated to the region in the 1960s following the Chinese occupation of Tibet. By studying Tibetan pastoralists’ coping strategies that they use to meet the changing physical environment (as a constitution of political, and socioeconomic change in the background), I will explore how their political status affects their ability to employ specific coping strategies. Drawing from critical social science, political ecology of climate adaptation, and political geography literature, I situate the experience of Tibetan refugee pastoralists and their plight in the global climate conversation as well as the regional climate change dialogue. I do so by exploring the intersection of climate vulnerability and political precarity.

In recent years, demand for cobalt—largely driven by demand for rechargeable lithium-ion batteries for electric vehicles and personal electronics—has grown faster than global cobalt production, necessitating a new look at the world’s cobalt resources and cobalt processing technologies. Oxide and oxyhydroxide ores constitute an important cobalt resource worldwide, and, if polymetallic seafloor nodules and crusts are included, make up the majority of global cobalt resources. The chief Co ore minerals in oxide ores are heterogenite (CoOOH or HCoO2) in stratiform sediment-hosted (SSH) Cu-Co ores, asbolane ((Ni, Co)xMn(O,OH)4∙nH2O) in Ni-Co laterite ores and some SSH deposits, and manganese oxide minerals such as vernadite (MnO2) in seafloor oxides, which are often also rich in Ni and Cu. Acid leaching is the cheapest and lowest-impact way to recover Co from oxide ores, but the precise mechanisms of cobalt-oxide leaching are not well characterized. In order to define major mineralogical factors in cobalt-oxide leaching performance, we leached Congolese SSH Cu-Co oxide ores and Pacific Ocean seafloor nodules in acid, then performed a comparative mineralogical study of leached and unleached samples using SEM-EDS and EPMA analyses. Both ores leached best under heat in a reducing environment, with maximum Co recoveries of 7% from our seafloor nodules and 99% from our SSH Cu-Co oxide ores. Recoveries of Ni and Cu from our seafloor nodules were as high as 40% and 33%, with a clear leaching gradient across our roughly 1 cm samples indicating that leaching was primarily limited by lixiviant access rather than by mineral leachability. We attribute the difference in Co recovery to the solubility of the host mineral’s lattice. Cobalt in SSH Cu-Co ores occurs in the relatively soluble Co-oxide lattice of heterogenite whereas Co in seafloor nodules substitutes for Mn in the relatively insoluble Mn-oxide lattice of vernadite, and consequently cannot be extracted with high recoveries without considerable, possibly prohibitive expense. Generalized to other ore types, the solubility of the mineral that hosts Co, as defined by the main structural metal, can be used as a broad guide to the leachability of Co in different oxide ores.

Plant communities are often used as a basis for ecosystem studies, as they both greatly impact, and are greatly impacted by environmental interactions. Vegetation in the Arctic is particularly sensitive to disruptions in temperature and water regimes, altering vegetation and thus species diversity, composition, productivity, structure, and biomass. Species have differential responses to regime shifts due to unique tissue types, nutrient composition, plasticity, and production and growth strategies. Accounting for these traits and processes in vegetation may aid in understanding ecosystem level problems, especially when such studies are conducted in a cross-disciplinary framework. Stordalen Mire in Abisko, Sweden is impacted by climate-mediated permafrost thaw, driving shifts in soil moisture, nutrient availability, and the composition of plant and microbial communities. Due to the topographical and hydrological heterogeneity of Stordalen, the distribution of the species is influenced by patch dynamics creating a mosaic of ecological subsections across the landscape -- each with a differing composition of plants and their traits. This guide is motivated by the value brought by knowledge of individual plant taxa and their traits, and the ways their reactions to change will affect both vegetation and broader processes in ecosystem functioning. Additionally, it provides a resource for scientists conducting studies related to plants by including a species list compiled through the literature, and identification information for some of the most common and influential species on Stordalen Mire. Of the 43 species recorded at Stordalen Mire, 26 are vascular plants and 17 are bryophyte species. These species are members of 26 genera, representing 21 families. Recent studies have called for examining immediate, subsequent, and long-term effects of climate on vegetation shifts – both on individual species and species assemblages. Literature reviews of these species have revealed patterns in phenology, physiology, competition, nutrient cycling, carbon fluxes, microbiome interactions, etc., providing a plethora of future directions of research.

Overfishing for fishmeal (FM) and oil (FO) has decimated populations, limiting their availability, inflating costs of fishmeal for commercial fish feeds worldwide. Incorporating insects as a protein source alongside, or in place of FM or FO, has the potential to increase food security globally in the future. This study evaluated the impact of insect meal (IM) substituted feeds with Tenebrio molitor, mealworm, on the growth rates of both fish and plants. One 12-week trial and one 17-week trial were conducted using T. molitor to produce fish feeds with 0% IM (control), 15% IM, and 25% IM substituted feeds for both. Each trial was performed with 6 separate coupled aquaponics systems (CAS) and both trials reared Nile tilapia (Oreochromis niloticus). The first trial grew butter lettuce (Lactuca sativa), and the second trial grew Ethiopian kale (Brassica carinata), Georgia Southern collard greens (Brassica oleracea), and chickpeas (Sierra kabuli). The CASs for these trials were designed with deep water culture (DWC) beds and floating rafts. The first trial revealed no significant differences in the change of fish biomass between treatments (p ≥ 0.05), and the second trial had a significant difference between the control and 25% IM (p ≤ 0.05). In the first trial the plant biomass increases of the control and the 15% IM treatments were significantly different than the 25% IM treatment (p ≤ 0.05). In the second trial there was no significant difference in collard green biomass between treatments, but there was a significant increase in Ethiopian kale biomass gain from the 25% IM treatment compared to the control (p ≤ 0.05). Lastly, there was a significant difference in chickpea production of viable seeds from tank 1, control, compared to all other CAS (p ≤ 0.05). In conclusion, these results support the potential for IM substituted feeds in aquaponics, and more research needs to be conducted in the future.

Adaptive management is a popular management approach in the field of natural resourcesand rangeland management. It is a method of decision-making that aims to reduce uncertainty in the face of environmental complexity to ultimately improve ecological, economic, and social outcomes. Despite the promise of this approach, adaptive management has been difficult for natural resource managers and researchers to define and analyze, making large-scale assessments of its effectiveness challenging. Our research attempts to fill this gap by analyzing a large-scale implementation of adaptive management by the United States Forest Service (USFS). In 2007, the USFS implemented a policy requiring the use of adaptive management for all grazing permits on grazing allotments in Region 3 (Arizona and New Mexico). There is little known about how this policy has been carried out in USFS Region 3 and how it has affected outcomes. We aimed to understand if and how adaptive management has been implemented on grazing allotments and how management has changed as a result by analyzing USFS compliance documents from 1996-2017. Allotment management plans and annual operating instructions (n=2,333) from nearly all Forests and selected districts in USFS Region 3 were coded to create a database including key management metrics that allowed for an analysis at the regional scale. Our data show that certain adaptive management indicators are observed in documents at increasing rates over time, especially after 2007. However, indicators of adaptive management did not necessarily correlate with physical changes in management observed in compliance documents, although some patterns were seen that could be attributed to adaptive management. Nevertheless, results from this study can help us understand both our interpretation of on-the-ground adaptive management, as well as improve future decision-making and policy implementation with the increased knowledge of how and where adaptive management is being carried out on Southwestern USFS rangelands.

In nectivorous pollinators, timing and pattern of allocation of consumed nectar affects fitness traits and foraging behavior. Differences in male and female behaviors can influence these allocation strategies. These physiological patterns are not well studied in Lepidoptera, despite the fact that they are important pollinators. In this study we investigate crop-emptying rate and nectar allocation in Manduca sexta (Sphingidae), and how sex and activity influence these physiological patterns. After a single feeding event, moths were dissected at fixed time intervals to measure crop volume and analyze sugar allocation to flight muscle and fat body. Then we compared sedentary and flown moths to test how activity may alter these patterns. Sedentary males and females emptied their crops six hours after a feeding event. Both males and females preferentially allocated these consumed sugars to fat body over flight muscle. Moths began to allocate to the fat body during crop-emptying and retained these nutrients long-term (four and a half days after a feeding event). Males allocated consumed sugar to flight muscles sooner and retained these allocated nutrients in the flight muscle longer than females did. Flight instigated increased crop-emptying in females, but had no effect on males. Flight did not significantly affect allocation to flight muscle or fat body in either sex. This study showed that there are inherent differences in male and female nectar sugar allocation strategies, but that male and female differences in crop-emptying rate are context dependent. These differences in physiology may be linked to distinct ways males and females maximize their own fitness.

The United States is facing a teacher attrition issue. This is exacerbated within the agricultural educator community due to additional duties beyond what is expected of a typical classroom teacher, compensation for those duties, and lack of administrative support. Despite adjacent research on teacher attrition, there remains a gap in knowledge about specific and effective administrative supports that can be provided to retain agricultural educators. The purpose of this multi-case study was to identify successful cases of administrator-agricultural educator relationships and describe how these administrators support Arizona agricultural educators with intracurricular programming as a part of the three-component model of School Based Agricultural Education (SBAE). Seven exemplary cases of SBAE programs with the presence of administrative support were identified in Arizona. Agricultural educators, CTE directors, and principals from each case were interviewed individually to capture their perspective on the administrative support offered at their site. Four themes emerged from the data: 1) Administrator structure is the machine, agricultural educator communication is the oil; 2) Greater vision and priority alignment between all parties yields stronger support; 3) Administrators engage with programs across a continuum of involvement; and 4) Administrators empower agricultural educators to be the stewards of their program. The presence and importance of relationships grounded in trust was the common undercurrent within each theme. Administrators and agricultural educators alike should strive to build trusting relationships through regular communication and collaboration. Aligning program visions between each party and working together towards collective ends also creates a supportive environment and encourages trusting relationships.