Publications

The Navajo (N) aquifer is an extensive aquifer and the primary source of groundwater in the 5,400-square-mile Black Mesa area in northeastern Arizona. Water availability is an important issue in the Black Mesa area because of the arid climate, past industrial water use, and continued water requirements for municipal use by a growing population. Precipitation in the area typically ranges from less

Niobium, often classified as critical, is typically embedded within steels essential for infrastructure and transportation. Most niobium-consuming countries are import-dependent on primary stage niobium, meaning traditional material flow analysis, which often excludes critical commodities embedded within products of large-scale industries, would miss important flows in the fabrication and manufact

Rapid Arctic environmental change affects the entire Earth system as thawing permafrost ecosystems release greenhouse gases to the atmosphere. Understanding how much permafrost carbon will be released, over what time frame, and what the relative emissions of carbon dioxide and methane will be is key for understanding the impact on global climate. In addition, the response of vegetation in a warmin

Informed and effective management of emerging infectious diseases can be improved by a clear understanding of host–pathogen–environment interactions. Impacts of the seasonal environment on pathogen dynamics and host responses are poorly described in most reptile host–fungal pathogen systems. Here, we describe seasonal patterns of ophidiomycosis, a disease caused by the fungus Ophidiomyces ophidiic

Pyrethroids, a class of commonly used insecticides, are frequently detected in aquatic environments, including estuaries. The influence that salinity has on organism physiology and the partitioning of hydrophobic chemicals, such as pyrethroids, has driven interest in how toxicity changes in saltwater compared to freshwater. Early life exposures in fish to pyrethroids cause toxicity at environmenta

A critical gap in planetary observations has been in situ characterization of extra-terrestrial, present-day atmospheric and surface environments and activity. While some surface activity has been observed and some in situ meteorological measurements have been collected by auxiliary instruments on Mars, existing information is insufficient to conclusively characterize the natural processes via con

In a stroke of good luck for aquatic scientists and insect enthusiasts, the May 2022 Joint Aquatic Sciences Meeting (JASM) in Grand Rapids, Michigan coincided with a spectacular hatch of hydropsychid caddisflies. To estimate density, we enumerated caddisflies on 12 polarized window panels on the western face of the DeVos Place, which faced the Grand River. We found an average of 57.8 caddisflies p

In many countries the use of lead-based ammunition is prevalent, and results in exposure and poisoning of waterfowl and other species of birds. In waterfowl hunting areas large quantities of spent shot may be deposited in wetland and terrestrial habitats. These pellets can undergo transformation, which are influenced by various abiotic and biotic factors. In addition to lead (Pb), other elements l

Depressional wetlands in the Prairie Pothole Region of North America have a long history of investigation owing to their importance in maintaining migratory-bird populations, especially waterfowl. One area of particularly intensive study is the Cottonwood Lake study area in Stutsman County, North Dakota. Studies at the Cottonwood Lake study area began in 1967 and continue through the present (2022

In today's complex global supply chains, time and data intensive analyses are required to understand global flows of mineral commodities from mine to consumer, particularly for mineral commodities in products (electronics, automobiles, etc.) that contain multiple parts with many mineral commodities. National and regional analyses require additional time and data to incorporate international trade

Aftershocks do not uniformly surround a mainshock, and instead occur in spatial clusters. Spatially variable physical properties of the crust may influence the spatial distribution of aftershocks. I study four aftershock sequences in Southern California (1992 Landers, 1999 Hector Mine, 2010 El Mayor—Cucapah, and 2019 Ridgecrest) to investigate which physical properties are spatially correlated wit

Naturally occurring gas hydrates may contribute to a positive feedback for global warming because they sequester large amounts of the potent greenhouse gas methane in ice-like deposits that could be destabilized by increasing ocean/atmospheric temperatures. Most hydrates occur within marine sediments; gas liberated during the decomposition of seafloor hydrates or originating with other methane poo