The south Puget Sound region has a history of smelting activity, notably the ASARCO smelter that operated in Ruston, WA. Despite the smelter being closed, the consequences of this smelting activity are still felt today. Due to high levels of arsenic contamination in the region’s soils, the area was designated a SuperFund site. Preliminary research conducted in 2014 indicated that several urban lakes in the Tacoma/Federal Way area also have high levels of arsenic in their sediments. If the arsenic is mobilized into the water column, where it can be taken up by lake biota and biomagnify up the food chain, it could potentially affect human health and ecosystem health. We examined two lakes, Angle Lake and Lake Killarney, that have the same amount of arsenic in their sediments, but different physical properties likely impact the release of arsenic into the water column. Angle is seasonally stratified, while Killarney remains well-mixed all year. Consequently, the bottom waters of Angle Lake stay at a relatively stable temperature of 4-10°C and consistently have arsenic concentrations between 30-100 ppb year-round. In contrast, bottom waters in Lake Killarney warm significantly from 4°C in the winter to 21°C in the summer and arsenic concentrations increase from 75 ppb to 700-1000 ppb. We hypothesize that temperature is the primary control on the release of arsenic from the sediments. To test this hypothesis, sediment cores were taken from each lake and placed into plastic tubes. To test this hypothesis, sediment cores were collected from each lake in the winter when all lakes have low bottom water temperatures. The cores were placed into two different temperature treatments, 10°C and 20°C. Samples of the water overlying the cores will be taken every week and measured using ICP-MS to determine the flux of arsenic out of the sediments.

Cystic fibrosis-related diabetes (CFRD) complicates up to 50% of adult cases with CF. However, its pathogenesis is poorly understood. One thing that has been shown, however, is that amyloid deposition occurs in the islets of 60% of subjects with CFRD, which is known, from data in other forms of diabetes, to be toxic to insulin-producing islet β-cells. Currently existing animal models do not reproduce this feature of human CFRD, since islet amyloid deposition requires the expression of an amyloidogenic form of the islet peptide islet amyloid polypeptide (IAPP). To address this gap in the field, our group is generating a CF mouse model that expresses the human amyloidogenic form of islet amyloid polypeptide (hIAPP). To do this, we have generated a double transgenic mouse from a male homozygous for the CF mutation and a female hemizygote for the hIAPP transgene. Mice will be followed for up to 12 months, or until hyperglycemia develops. During this time, body weights and non-fasted blood glucose levels will be measured monthly. When hyperglycemia is identified, animals will be euthanized in order to determine if islet amyloid is present in the pancreas. We are expecting to find that mice bearing the CF mutation and expressing the hIAPP transgene will develop increased and/or accelerated amyloid deposition in their islets as compared to the control mice generated by the cross. In addition to this, we expect that these mice will also show increased glucose levels (hyperglycemia) and decreased β-cell mass. There are currently 16 mice on study, and data collection is ongoing, with additional animals being enrolled approximately every two weeks. The goal of this study is to generate a new model of CFRD, which better reflects the human disease state, and can be used to develop and test improved therapies for human CFRD.

This research looks at the impact of elevated temperatures on rice biomass allocation, in the context of rice nutrient and contaminant uptake. Below-ground biomass allocation can influence the rate of mineral uptake, and above-ground biomass can influence how those nutrients are distributed. Rice was grown in four growth chambers set to different temperatures ranging from low (25.4°C) to high (33.0°C). Rice plants were harvested during two developmental stages, flowering and grain filling. The plants were sectioned into four components before storage and desiccation: roots, leaves, stems, and grain. A total of 256 rice plants were grown over two harvesting periods, thus each treatment has a sample size of 64 plants. To examine biomass allocation, each component is being measured on a high-precision scale accurate to the nearest 10^-5 gram. The impact of temperature will be quantified for the following groups: temperature treatment vs. component biomass, treatment vs. above- and below-ground biomass ratio, and treatment vs. total biomass. Rice is the primary staple food of over half of the world's population and is the main caloric and nutritional source in many developing countries. Increased global temperatures due to climate change may have significant impacts on rice growth, yield, and nutritional quality.

Within the complex San Juan Channel (SJC) ecosystem, marine birds play a fundamental and dynamic role. Due to their interactions with several trophic levels and climatic factors, seabirds are important indicators of environmental health. Their necessity to be monitored is further compounded by the fact that the SJC has recently experienced abnormal sea surface temperatures and conditions due to the Marine Heat Wave in 2013 – 2016. Thus, our goal was to monitor how the marine bird communities have been impacted by these climatic changes. We first characterized the Fall of 2017 by collecting survey data on community composition and temporal and spatial densities. Then, we contextualized 2017 within the past 10 years of survey data. In order to highlight the specific species that have large influences on the overall bird density, we focused on 5 main species: the Glaucous-winged Gull, Brandt's + Pelagic Cormorant, Common Murre, Surf + White winged Scoter, and Pacific Loon. We found that 2017 had the lowest total bird density in the past decade, as well as a complex mixture of temporal and spatial trends from previous study years. Additionally, we were able to highlight the significant connections between marine birds and three climatic indices - North Pacific Gyre Oscillation (NPGO), Oceanic Niño Index (ONI), and Sea Surface Temperature (SST). Our findings indicate that these communities are impacted by both local and global water and air conditions. However, many of the migratory birds, such as Common Murres, are perhaps impacted greater by changes in their remote habitats, such as their breeding grounds and migratory routes. Additionally, Common Murres proved to be a main driving species behind annual density trends, even frequently masking other more minute density trends in less abundant birds. Further research is needed to understand the relationships between species-specific densities and other climatic patterns.

Increased levels of atmospheric carbon dioxide (CO2) reduce the nutritional content of rice grains, particularly iron (Fe) and zinc (Zn). Rice serves as a staple food crop for more than two billion people across the world; substantial portions of these rice-dependent populations also suffer from iron and zinc deficiencies. In rice, the effect of increased CO2 on Fe and Zn differs between cultivars. With better mechanistic understanding as to why, informed plant breeding and cultivar selection is a likely path towards ameliorating this problem. Little is known about the mechanisms behind CO2-induced reduction of grain nutrition. Increased CO2 changes the pH of rice paddy soil, facilitating the release of cations (including Fe and Zn), which leads to increased uptake to above ground plant tissues. However, this does not result in increased concentrations of these compounds in the rice grain. Several explanations have been advanced for this paradox, but most work on the topic has relied on free-air carbon enrichment (FACE) installations, which cannot control many potentially important variables. In particular, reduced transpiration under elevated CO2 may obscure differences between CO2-induced carbohydrates. Additionally, the fine-scale impacts of elevated CO2 on the rice rhizosphere have been poorly studied. Our study is attempting to close these knowledge gaps: we have grown rice plants under elevated and current CO2 conditions, while maintaining even transpiration between treatments via controlled relative humidity. We have paired these experimental manipulations with oxygen optode-based visualizations of the undisturbed rice rhizosphere, which has directed accurate soil sampling of rhizosphere and bulk soil porewater samples for analysis of pH, redox, total organic carbon (TOC), and quantification of Fe, As, Ca, Mg, and Zn. Our study seeks to better understand the mechanistic role of increased CO2 on the rice rhizosphere, and its downstream effect on rice grain nutrient quality.