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This study examines the spatial variability of shallow groundwater on Dhigelaabadhoo Island using electromagnetic induction surveys, groundwater monitoring, and sediment analyses. The research reveals how variations in island morphology—such as differences in elevation, reef flat width, and sediment composition—affect the spatial distribution of groundwater lenses and the overall aquifer dynamics....

The critical carbon sink provided by coastal wetlands, known as blue carbon, can be affected by multiple aspects of climate change. One important example is warming-induced mangrove poleward expansion, which is shifting dominant plant cover across tropical–temperate transitional zones and altering ecosystem structure and function. We examined how mangrove expansion...

The West and Central African Rift System (WCARS) refers to the series of Cretaceous rift basins where commercial hydrocarbon accumulations have been discovered. Some of the WCARS frontier basins are currently being investigated to increase our understanding of these basins in light of new commercial discoveries. The present study was...

Accurate reconstructions of past environmental changes are crucial in paleoecological research and require reliable chronologies of sedimentary archives. Establishing robust age-models and obtaining the most appropriate proxies for analysis is a complex scientific endeavor, requiring extensive resources and collaboration among specialists, including radiochronologists. Radiometric dating methods, such as 210Pb and radiocarbon...

Grizzly bear (Ursus arctos) feeding on migratory army cutworm moths (Euxoa auxiliaris) was first documented by the Interagency Grizzly Bear Study Team (IGBST) during the early 1980s in the southeastern portion of the Greater Yellowstone Ecosystem (GYE). Since those initial observations, use of this seasonally available food resource by grizzly...

Oyster and seagrass are important sessile, habitat-forming species that may be impacted by changes in salinity regimes from anthropogenic or climatic drivers. While salinity tolerance literature is focused on controlled experiments, observed field salinity ranges of species are more disparate. The salinity ranges in which organisms are observed in the...

Anhydrite is considered a rare mineral phase in magmas, with only ∼33 documented occurrences worldwide. However, anhydrite readily decomposes in the near-surface environment, making it difficult to recognize its former presence in rocks collected at or near Earth’s surface. In such samples, only small anhydrite inclusions fully shielded within other...

Estimating spatial and temporal patterns in abundance is often a goal of ecological studies and can be useful for informing management decisions, such as determining the optimal placement of wildlife protection zones. However, estimating abundance can be difficult in practice, especially over large areas, because of imperfect detection, where individuals...

Considering potential cumulative effects of proposed actions is fundamental to environmental impact analysis. However, cumulative effects analyses historically are not robust, especially for site-specific decisions. We sought to identify opportunities to strengthen cumulative effects analysis in a large United States public land management agency, the Bureau of Land Management (BLM)....

Chronic selenium (Se) water quality criteria are based primarily on dietary organoselenium exposure and subsequent reproductive effects in fish. Available chronic Se toxicity data suggests that invertebrates are less sensitive than fish, but chronic invertebrate studies are limited. We evaluated yeast-based diets for chronic toxicity studies with Hyalella azteca and Chironomus dilutus. Growth and...

Seismology has been used as a tool for understanding the current physical properties of the interior of the Earth and its dynamic evolution with remarkable success over the...

Understanding how social vulnerability relates to disaster impacts is critical for addressing social equity, yet the role of spatial scale in this relationship is often overlooked. Most studies use aggregated data, risking ecological fallacy—misinterpreting individual outcomes from group-level data. This study examines how spatial scale influences the relationship between social...

More than 3 m.y. of mafic volcanism near the Goat Rocks volcanic cluster in the southern Washington Cascade Range, USA, lends insight into the evolution of basalts and the subarc mantle at a long-lived, major arc volcanic locus. We contribute field observations, 40Ar/39Ar dates, paleomagnetic directions, and bulk rock and mineral...

IntroductionAmerican black bears (Ursus americanus) have been documented to have top-down effects, both consumptive (through predation) and nonconsumptive (through fear effects). However, their behavioural and dietary adaptability has led to uncertainty about the conditions under which these may occur.ObjectivesWe aimed to (1) investigate when,...

Although the aquarium trade is an important pathway for direct and indirect non-native species introductions into freshwater systems, knowledge and attitudes of participants in the trade regarding alien species issues is largely undocumented. Therefore, we administered a survey to investigate attitudes and behaviors of aquarists and non-aquarists regarding the aquarium...

Economic concentrations of rare earth element (REE) minerals are uncommon in the Earth’s crust, with most occurring in carbonatites. Unlike most igneous rocks composed of silicate minerals, carbonatites are dominated by carbonate minerals, some of which can incorporate significant light REEs (LREEs; La, Ce, Pr, Nd). Technological applications of REEs...

The majority of submarine canyons on Earth today do not directly intersect littoral or fluvial sediment sources, yet these systems are rarely studied. The shelf-incised head of Astoria Canyon receives sediment from the nearby Columbia River and is subject to energetic forcing from shelf and slope processes, making it an ideal site to evaluate...

The rate of earthquakes in a region is a fundamental input to Probabilistic Seismic Hazard Analysis. We present a Monte Carlo method for computing that rate from seismicity catalogs while including a range of data and analysis uncertainties. This method is applied to regions for which the b value is assumed to...

The Meadow Bank scarp (MBS) in southeastern Illinois is a linear geomorphic expression, ∼10 km long and ∼8 m high above a relatively flat landscape. It parallels an underlying northeast‐oriented Late‐Precambrian–Early‐Cambrian structural fabric, called the Wabash Valley fault zone, and is within an area of modern, historic, and paleo seismicity, called the...

The hydrology of the Upper Mississippi and Illinois Rivers is a fundamental driver of ecosystem patterns and processes across a large portion of the United States. Quantitative hydrologic data for the main stems of these rivers underlie numerous scientific investigations, statistical models, and decision-making processes for local, State, and Federal...

he North American porcupine (Erethizon dorsatum) is widely distributed throughout many ecosystems on the continent from northern Mexico to the Arctic Ocean, except for the southeastern portion of the United States. Habi­tats include the arid Desert Southwest region where modern records are generally sparse. The paleogeographic range in the Desert...

Environmental decision-support tools are increasingly being used to serve both expert and non-expert audiences. Many existing tools are primarily expert-focused, and redesigning them can be challenging because experts and non-experts interact with tools differently, existing users may be resistant to changes, and there is little guidance on how to prioritize...

In April 2021, a synoptic study conducted by the U.S. Geological Survey (USGS) and National Park Service (NPS) identified wastewater-related contaminants of emerging concern (CECs) in springs along the South Rim of the Grand Canyon. These springs are located north of Bright Angel Wash, an ephemeral channel that receives treated...

PurposeIdentifying suspended-sediment (SS) sources, seasonal variability, and phosphorus (P) transported with SS is critical information for basin managers, although there may be concerns about comparability between flow-integrated SS samples used for sediment fingerprinting and discrete samples used for concentrations and loads in basins where SS is mostly silt + clay...

The relation between the groundwater and the amount of natural recharge to the Cahuilla Valley and Terwilliger Valley groundwater basins is not well understood. During the 20th century, the reliance on groundwater near Anza, California, used for agricultural, domestic, and municipal reasons has increased, and there is the potential for...