Physical Sciences and Mathematics Commons^™

A Multivariate Analysis Of The Relationship Between The Water Quality Conditions And Algal Species Composition Of Six Mountain Lakes In The North Cascades, Wa, Usa, Michael P. Lawlor

WWU Graduate School Collection

The objective of my study was to characterize the water quality conditions and algal species composition of six mountain lakes in the North Cascades of Washington, USA. Exploratory data analysis examined water quality conditions and algal species composition separately, then determined if they were related. The lakes exhibited median temperatures from 13.3 °C to 20.8 °C, had nitrate and soluble reactive phosphate concentrations below 100 µg/L and 6 µg/L, respectively, were slightly acidic (pH 5.1-6.9), and had median dissolved oxygen concentrations ranging from 6.7 mg/L to 10.6 mg/L. Over 340 non-diatom algal taxa were identified. Algal species richness was positively …

Development Of A Rangeland Degradation Risk Model For The Peruvian Andes, Colin Schmidt

WWU Graduate School Collection

This study developed a Rangeland Degradation Risk Model for the Peruvian Andes based on the Unit Stream Powered Erosion Deposition Model using globally available datasets. A supervised land cover classification was conducted to identify suitable grazing areas and to conduct a regional analysis of susceptibility to erosion. Field data were collected from two different study sites, Huascaran National Park and Nor Yauyos Cochas Landscape Reserve, and were used to assess the model’s accuracy in different ecosystems and land use types. Field data were also leveraged to identify additional data needs and other potential drivers of degradation not taken into account …

Everyone Can Grow! Winter Programming Using An Indoor Horticulture Environmental Education Program To Benefit Military Veterans, Rachel Elam

WWU Graduate School Collection

Working with plants has numerous physical, mental health and well-being benefits for people, and military veteran farming programs have been started to provide these benefits. However, these programs lack activities outside of the Washington State growing season which is approximately May to October. Since these programs are largely meant as ways for veterans to engage in community and peer support, the gap over winter is unacceptable for the purposes of supporting mental health. This project produced a winter environmental education curriculum for military vets, titled Everyone can Grow! (ECG!), and is designed to provide peer support and psychological …

Under What Conditions Could Eelgrass Measurably Drawdown Carbon? Relating Carbon Drawdown To Pco2, Irradiance, And Leaf Area Index Of Zostera Marina, Tyler Tran

WWU Graduate School Collection

Seagrass meadows, common to coastal habitats, have been identified as potential short-term refugia for calcifying organisms from ocean acidification (OA). In nearshore, soft-sediment habitats of the Salish Sea, eelgrass (Zostera marina L.) is the dominant seagrass species, and several studies have found that eelgrass is effective at taking up inorganic carbon and may be carbon-limited, potentially increasing uptake potential in the future. However, irradiance levels vary throughout a day and can therefore influence rates of carbon uptake and release through the relative rates of photosynthesis and respiration. Eelgrass meadows vary in terms of meadow size, shoot density and morphology, …

A Needs Assessment Of The Perceptions And Opportunities To Enhance Nature Exploration At Publicly Funded Preschools, Naomi Liebhold

WWU Graduate School Collection

Extensive research supports the benefits of nature exploration in children’s lives. Research also suggests, however, that low-income families and other historically marginalized groups experience multiple barriers to accessing green spaces. In an attempt to counteract this inequality, a needs assessment was performed to understand the challenges and barriers public preschool providers face in regularly leading their children in nature exploration. The target audience of this evaluation was Head Start and Early Childhood Education and Assistance Program [ECEAP] teachers and parents. Along with measuring the challenges and barriers at these centers in regard to nature exploration, this evaluation assessed the resources …

Impacts Of Major Freshwater Ions On The Acute Toxicity And Chemical Behavior Of Silver Nanoparticles, Claire A. Walli

WWU Graduate School Collection

Silver nanoparticles (AgNPs) are increasing in presence in commercial and medical products due to their bactericidal properties and can be transported into the environment during the laundering, use, and waste of those products. Strong evidence suggests aqueous silver (Ag⁺) dissolved from the AgNP surface is the toxic component of AgNPs but there is no consensus on the possibility of additional nanoparticle-specific properties that elicit toxicity. Ag⁺ toxicity to freshwater organisms has been well studied using the Biotic Ligand Model (BLM), which describes how water quality conditions, such as the concentrations of certain freshwater ions, affect the toxicity …

Springtime Benthic Fluxes In The Salish Sea: Environmental Parameters Driving Spatial Variation In The Exchange Of Dissolved Oxygen, Inorganic Carbon, Nutrients, And Alkalinity Between The Sediments And Overlying Water, Emma I. Rigby

WWU Graduate School Collection

Recent decades have seen changes to biogeochemical cycles in the Salish Sea, including alterations in water column nutrients, an expansion of hypoxic zones, and bottom water acidification. Marine sediments can be a major contributor to these biogeochemical cycles by exchanging solutes with bottom water. In an effort to understand the sediment biogeochemistry of the Salish Sea further, benthic fluxes of dissolved oxygen (DO), dissolved inorganic carbon (DIC), pH, total alkalinity (TA), and nutrients (ammonium, nitrate+nitrite, phosphate, silicate) between the sediment and the overlying water were directly measured using incubated flux cores at 42 sites in April and early May 2018. …

Not Just Nature, Sarah Kellogg

WWU Graduate School Collection

This field project, entitled Not Just Nature, consists of three parts: the first being a curriculum by the same name. This curriculum, an arts-based workshop series, has been/is being developed to open conversations to interrogate the colonial and white supremacist concepts of nature that have been created in the United States through a variety of means.

The second part of this project is using self as a site of research/critical autoethnography. No field is apolitical, and the creator/researcher will always bring pieces of themselves and their identities to whatever processes they participate in. Thus, throughout my graduate experience I have …

Dendroclimatology Of Yellow Cedar (Callitropsis Nootkatensis) And Late Holocene Temperature Variability On The Western Slopes Of The North Cascades In Washington State, Christopher A. (Chrisopher Anthony) Trinies

WWU Graduate School Collection

Subalpine tree growth in the Washington Cascades is often limited by both growing season temperatures and persistence of the winter snowpack, making paleoclimate inferences on temperature alone difficult. Here I expand on three yellow cedar chronologies on the west slopes of the North Cascades and build chronologies for two co-dominant species at one of the sites. I used the VIC hydrologic model to include biologically relevant proxies for water stress, including evapotranspiration deficit, and snow cover in a climate-growth analysis. The co-dominant species, specifically mountain hemlock, showed a climate response reminiscent of a high-elevation, energy-limited environment with an interaction between …