The Climate-Ready Landscape Plants Project evaluates the relationship between irrigation and landscape plant performance across different geographic and climatic regions. Given that few horticultural plants have been tested under varied irrigation treatments, this project investigates four overlapping taxa–Physocarpus ‘Diabolo’, Physocarpus ‘Little Devil’, Cercis occidentalis, and Cercis canadensis–and how their xylem anatomy changes in response to water deficits across three different planting sites. I expected both C. canadensis and C. occidentalis to display smaller vessels per xylem area reducing vulnerability to drought induced cavitation, with Cercis canadensis displaying stronger acclimation to drought conditions because of its high tolerance for cold temperatures. ‘Diabolo’ and ‘Little Devil’ vessels were predicted to display lesser plasticity in xylem size and density. At each site, 24 replicates per taxa and 8 plants per irrigation treatment were tested under a two-year trial period. In Year 1, plants received the same water treatment; Year 2, plants were introduced to irrigation treatments of 20% and 80% based on the Water Use Classification of Landscape Species. I then analyzed vessel sizes of stained stem cross sections using ImageJ. No difference in water use efficiency was found when comparing species under the two irrigation treatments. However, Physocarpus is ornamentally selected and hybrids of the Physocarpus genus showed reduced water use efficiency with a lesser ability to acclimate to drought conditions. These findings can inform the production and utilization of low water-use plants to create well adapted landscapes under a changing climate for horticulture efforts on a local and industrial scale.

Vertical velocities are a fundamental component of ocean flow and are vital to characterizing global circulation. However, vertical velocities are small compared to horizontal velocities and are thus difficult to measure. Previous studies attempting to estimate them ignore the impacts of topography, mesoscale eddies, internal waves, and spatial variability. Novel estimates from the Argo float array allow for direct estimates of vertical velocities. This project will focus on comparing these new Argo estimates with vertical velocity observations from moorings in the Southern Ocean. The Southern Ocean is an important site of vertical volume transport for mass ocean circulation with global implications, particularly the Antarctic Circumpolar Current which dynamically links many of these interactions. We expect vertical velocity characterized by moorings to maintain coherency with Argo float estimates. Differences may occur, however, due to mismatches in spatial resolution between Argo-based estimates and mooring-based estimates, which rely on mass conservation across larger scales. In comparing novel Argo datasets to known mooring values, we gain a more complete understanding of vertical velocities in the Southern Ocean which have direct implications for data assimilation in models and parameterization of energy pathways.

Increasing concerns over large-scale contamination of water, food, and waste from polyfluoroalkyl substances (PFAS) have led to growing global pressure to identify and monitor PFAS - a not well understood substance - in the environment. To improve the understanding of the environmental sources and cycling of PFAS, we have initiated a research project to look at the substance's historical deposition in water body sediments. Lake sediments, as demonstrated with other legacy and emerging contaminants, provide an accurate archive of historical contaminant deposition which can be useful to establish a deposition history of PFAS. The primary focus of this study aims to modify the poorly characterized atmospheric cycling and deposition of PFAS through the use of seepage lakes whose inputs are dominated by atmospheric deposition. The sediment cores extracted from the two seepage lakes in southern Wisconsin reach back to the early 1900’s, well before PFAS was first produced. The cores were sectioned at 1 cm intervals, which were dated using 210-Lead and 137-Cesium, to establish timelines for PFAS deposition history. This research aims to gain a better understanding of the distribution of historical inputs of PFAS, ultimately contributing to strategies that control future inputs of PFAS compounds in an effort to protect the environment and improve public health.

Compact steep spectrum (CSS) sources are believed to be young radio galaxies that are characterized by their small jett size. CSS radio sources are most commonly located in massive elliptical galaxies with little to no ongoing star formation. While the majority do not exhibit star formation, previous studies suggest galaxy mergers may trigger star formation in a small portion of CSS sources. This is because radio galaxies have a higher merger rate than non-radio galaxies. As CSS sources are young radio galaxies, they may also exhibit higher merger rates as well. The scope of this project is to determine if CSS galaxies are more likely to be present in merging galaxies compared to non-CSS sources. We blindly classify optical images of 2,500 radio sources, which include 166 known CSS sources, based on morphology, to determine whether each exhibits merger activity. Based on these results, we aim to determine the rate of CSS source involvement in galaxy mergers. This research contributes to our current understanding of the influence galaxy mergers have on star formation in CSS sources. This can enable us to understand how CSS sources change over time.