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The Zuni Salt Lake is located in a maar in west-central New Mexico and contains hypersaline water that has long been used by Native Americans for religious purposes and the collection of salt. There have been several investigations suggesting different sources for the water and salt to the lake. Springs,...

Arctic cod (Boreogadus saida, also called polar cod) are considered the single most important Arctic forage fish due to their high abundance and nutritional quality. Because Arctic cod are strongly ice associated and prefer colder waters, their frequency in coastal waters has declined with warming, decreasing availability to nearshore predators....

Light and temperature are driving forces that shape the evolution and physiology of mesophotic organisms. On the Mississippi-Alabama continental shelf, octocorals dominate the mesophotic seascape and provide habitat for many fish and invertebrate species. Gaps in knowledge regarding the fundamental physiological responses of these species to light and temperature are...

Many ecological processes affect the availability of winter dissolved oxygen (DO) concentrations in rivers, a key feature of overwintering fish habitat. Sediment oxygen demand (SOD) contributes to DO depletion, particularly during ice-covered periods, and may cause hypoxic conditions in backwater lakes, affecting the availability of suitable overwintering...

Hydrologic connectivity (HC), particularly in floodplain systems, is pivotal in regulating ecosystem services by facilitating the movement of nutrients, sediments, chemicals, and biota. However, human interventions such as dam construction, levee installation, water management practices, and alterations in vegetation have significantly disrupted natural HC patterns globally. To provide a structured entry...

Many know Jamestown Island, Virginia, hereafter referred to as “the Island,” located near the mouth of the James River into the Chesapeake Bay, as the home of the first permanent English settlement in North America. However, the Island is home to 15,000 years’ worth of cultural artifacts and archaeological sites....

The timing and failure conditions of an earthquake are governed by the interplay between fault reloading and restrengthening. The moment-recurrence time behavior of repeating earthquakes can give observational estimates of fault healing rates; however, it is difficult to link these observed healing rates to laboratory studies of frictional healing in...

Greater Sage-grouse (Centrocercus urophasianus) populations have been in decline for decades across much of the US Intermountain West. However, findings from 25 years of lek counts in Idaho indicate that some populations are stable or even increasing. After accounting for potential biases in past lek count data, we sought to explain...

Accelerating global change is a hallmark of the Anthropocene, and the interaction of rapid change in climate, land use and land cover makes understanding the response of social-ecological systems to global change difficult to predict. Global change directly and indirectly affects both social-ecological systems and the landscapes in which they...

Desert dunes are often assumed to have uniform mineral compositions due to extensive mixing during lateral transport, which complicates provenance studies. The Mu Us Sandy Land in north-central China, near the East Asian summer monsoon precipitation boundary, experiences a wetter climate than most deserts. Climate wetting as a result of...

Tropical forests are a dominant regulator of the global carbon cycle, exchanging more carbon dioxide with the atmosphere than any other terrestrial biome. Climate models predict unprecedented climatic warming in tropical regions in the coming decades; however, in situ field warming studies are severely lacking in tropical forests. Here we...

Anthropogenically forced climate shifts disrupt the seasonal behavior of climatic and hydrologic processes. The seasonality of streamflow has significant implications for the ecology of riverine ecosystems and for meeting societal demands for water resources. We develop a hierarchical Bayesian model of daily streamflow to quantify how the...

The lack of information on what constitutes suitable habitat for native freshwater mussels can limit restoration efforts. While many species reside in silt–sand–gravel substrates, species such as the Spectaclecase (Cumberlandia monodonta) and Salamander (Simpsonaias ambigua) mussels are thought to be associated with rock structures (e.g., wing dams...

Ferromanganese mineral precipitation in the global oceans is ubiquitous, occurring in the form of both crusts and nodules at a broad range of depths and seafloor terrains. Although ferromanganese crusts and nodules are both composed of ferromanganese minerals, mineralogy and mean element concentrations compiled for regional crust versus nodule occurrences...

Gold, antimony, and tungsten resources of the Stibnite-Yellow Pine district, Idaho, are hosted in complexly faulted Late Cretaceous Atlanta Lobe of the Idaho batholith and surrounding Neoproterozoic-Paleozoic metamorphic rocks. This study utilizes detailed petrography and trace element chemistry of quartz to establish relative timing relationships between successive ore forming events...

Hydrothermal graphite veins are a possible source for modern battery materials and require better understanding of their carbon source(s) and absolute timing to develop mapable criteria for exploration models. We present new observations of graphite vein and alteration paragenesis and U-Pb LA-ICP-MS titanite age data from the Ruby prospect, Montana,...

The 40Ar/39Ar geochronology method is used to date potassium-bearing rocks and minerals, based on the decay of 40K to 40Ar, which provides important temporal constraints for geological events. The USGS Denver Argon Geochronology Laboratory dates samples from a variety of projects, mainly in the USGS Mineral Resource Program and the...

Lithium is a high-demand, critical element used not only in lightweight rechargeable lithium-ion batteries, but also in nuclear applications and industries producing ceramics, aluminum, and medical products. It is extracted primarily from pegmatites and volcano-sedimentary brines and clays in arid, closed lacustrine or caldera basins. Lithium brines of the central...

Rivers of the northern Great Plains have lacked long-term, continuous water temperature assessments, and there is limited information on thermal regimes of these systems and factors driving water temperature. We collected and assembled 2001–2022 water temperature data from 18 sites on four reaches of three rivers that differ in anthropogenic...

Remote sensing has emerged as an effective tool for characterizing river systems, and machine learning (ML) techniques could make this approach even more powerful. To explore this possibility, we developed an ML-based workflow for hyperspectral imaging of river bathymetry using an ensemble of regression trees (HIRBERT). This approach involves using...

The National Landscape Conservation System consists of unique and beautiful places across America’s landscapes where identified resources and values are protected and science is highlighted. The mission of the National Landscape Conservation System (NLCS), which is managed by the Bureau of Land Management and is often referred to as the...

Non-target animal sensitivity remains a concern when treating Laurentian Great Lakes streams with 4-nitro-3-(trifluoromethyl)phenol (TFM), the main pesticide used to control Sea Lamprey Petromyzon marinus as part of the bi-national Great Lakes Fishery Commission's Sea Lamprey Control Program. Populations of Burbot Lota lota, a historically and culturally important fish, inhabit some of the...

Near-surface seismic velocity structure may significantly impact the intensity, duration, and frequency content of ground shaking during an earthquake. In this study, we compile 649 shear wave velocity (Vs) profiles throughout the U.S. Pacific Northwest and southern British Columbia (PNW) and use these measured profiles to develop a representative soil...

Management plans with clear priorities can help to achieve brown pelican Pelecanus occidentalis conservation objectives in the northern Gulf of America (Gulf of Mexico). Efforts to establish clear priorities can be hindered by information gaps, especially those related to the uncertainty associated with changing conditions that influence brown pelican populations. We addressed...

The diatom biochronology of ODP (Ocean Drilling Program) Holes 682A and 688E provides a detailed framework for refiningMiocene diatom zonation in the East Pisco Basin of southern Peru, establishing both a nearly complete offshore reference section and a correlation tool for the fragmentary onshore vertebrate-bearing deposits. This new biostratigraphic record...