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Geologic reservoirs containing gas hydrate occur beneath permafrost environments and within marine continental slope sediments, representing a potentially vast natural gas source. Numerical simulators provide scientists and engineers with tools for understanding how production efficiency depends on the numerous, interdependent (coupled) processes associated with potential production strategies for these gas...

Predictions of post‐wildfire flooding and debris flows are needed, typically with short lead times. Measurements of soil‐hydraulic properties necessary for model parameterization are, however, seldom available. This study quantified soil‐hydraulic properties, soil‐water retention, and selected soil physical properties within the perimeter of the 2017 Thomas Fire...

Abstract Two of the remaining coregonine species in Lake Ontario, cisco (Coregonus artedi) and lake whitefish (C. clupeaformis), spawn in Chaumont Bay, NY. Larvae co-occur in the spring but are difficult to distinguish morphologically. We applied genetic species identification using microsatellite DNA loci of 268 larvae from known locations in nearshore...

Environmental DNA (eDNA) analysis offers a promising tool for rapid and early detection of aquatic plant invasive species, but currently suffers from substantial unknowns that limit its widespread use in monitoring programs. We conducted the first study to test the factors related to eDNA-based detectability of 2 invasive aquatic plants, Egeria...

The importance of critical minerals and the need to expand and diversify critical mineral supply chains has been endorsed by the Federal governments of Australia, Canada, and the United States. The geoscience organizations of Geoscience Australia, the Geological Survey of Canada and the U.S. Geological Survey have created the Critical...

The U.S. Geological Survey, in cooperation with the South Carolina Department of Transportation, investigated the effects of stormwater runoff from bridge decks on stream water quality conditions in South Carolina. The investigation assessed 5 bridges in 3 physiographic provinces in South Carolina (Piedmont, Upper Coastal Plain, and Lower Coast Plain)...

When animals select areas to occupy, decisions involve trade-offs between the fitness benefits of obtaining critical resources and minimizing costs of biotic and abiotic factors that constrain their use. These processes can be more dynamic and complex for species inhabiting desert environments, where highly variable spatial and temporal distribution of...

The transport of H2O ice along the retreating north polar seasonal CO2 ice cap has previously been modeled and observed. Spectral observations show that H2O ice forms on the interior of the seasonal cap, while thermal observations show these regions to be consistent with CO2 ice. Prior to the...

While deposition of reactive nitrogen (N) in the 20th century has been strongly linked to changes in diatom assemblages in high-elevation lakes, pronounced and contemporaneous changes in other algal groups suggest additional drivers. We explored the origin and magnitude of changes in two mountain lakes from the end of the...

Our current understanding of semiarid ecosystems is that they tend to display higher vegetation greenness on polar-facing slopes (PFS) than on equatorial-facing slopes (EFS). However, recent studies have argued that higher vegetation greenness can occur on EFS during part of the year. To assess whether this seasonal reversal of aspect-driven...

Paleoseismic rupture histories provide spatiotemporal models of earthquake moment release needed to test numerical models and lengthen the instrumental catalog. We develop a model of the fewest and thus largest magnitude earthquakes permitted by paleoseismic data for the last 1,500 years on the southern San Andreas and San Jacinto Faults, California,...

Soil erosion by water affects soil organic carbon (SOC) migration and distribution, which are important processes for defining ecosystem carbon sources and sinks. Little has been done to quantify soil carbon erosion in the three major basins in China, the Yangtze River, Yellow River and Pearl River Basins, which contain...

After more than 100 years of earthquake research, earthquake forecasting, which relies on knowledge of past fault rupture patterns, has become the foundation for societal defense against seismic natural disasters. A concept that has come into focus more recently is that rupture segmentation and cyclicity can be complex, and that...

While nest attentiveness plays a critical role in the reproductive success of avian species, little nest attentiveness data with high temporal resolution is available for many species. However, improvements in both video monitoring and temperature logging devices present an opportunity to improve our understanding of this aspect of avian behavior....

Recovery of salmon populations in the upper Cowlitz River Basin depends on trap-and-haul efforts owing to impassable dams. Therefore, successful recovery depends on the collection of out-migrating juvenile salmon at Cowlitz Falls Dam (CFD) for transport below downstream dams, as well as the collection of adults for transport upstream from...

While the physical processes governing groundwater flow are well understood, and the computational resources now exist for solving the governing equations in three dimensions over continental-scale domains, there remains substantial uncertainty about the subsurface distribution of the properties that control groundwater flow and transport for much of the contiguous United...

Empirical thresholds for landslide warning systems have benefitted from the incorporation of soil‐hydrologic monitoring data, but the mechanistic basis for their predictive capabilities is limited. Although physically based hydrologic models can accurately simulate changes in soil moisture and pore pressure that promote landslides, their utility is restricted...

Assessments of groundwater and surface water budgets at a large scale, such as the contiguous United States, often separately analyze the complex dynamics linking the surface and subsurface categories of water resources. These dynamics include recharge and groundwater contributions to streamflow. The...

As the Arctic warms and wildfire occurrence increases, talik formation in permafrost regions is projected to expand and affect the cycling of water and carbon. Yet, few unified field and modeling studies have examined this process in detail, particularly in areas of continuous permafrost. We address this gap by presenting...

We conducted a national-scale assessment of mercury (Hg) bioaccumulation in aquatic ecosystems using dragonfly larvae as biosentinels, by developing a citizen science network to facilitate biological sampling. Implementing a carefully designed sampling methodology for citizen scientists, we developed an effective framework for landscape-level inquiry that might otherwise be resource limited....

Recently, Stovall et al.1 (hereafter SSY) showed that during an extreme drought, remotely sensed mortality of tall trees was more than double that of short trees. They interpreted this to be a consequence of inherently greater hydraulic vulnerability of tall trees, and suggested that tall-tree vulnerability should thus generalize...

The order Beloniformes (or Synentognathi) contains two suborders, six families, 37 genera, and about 235 species of atherinomorph fishes (Rosen & Parenti 1981; Collette et al. 1984; Collette 2004). Features common to these fishes include dorsal and anal fins on the rear half of the body, abdominal pelvic fins with...

The U.S. Army Corps of Engineers, Jacksonville District, plans to deepen the St. Johns River channel in Jacksonville, Florida, from 40 to 47 feet along 13 miles of the river channel, beginning at the mouth of the river at the Atlantic Ocean, in order to accommodate larger, fully loaded cargo...

Human behavioral response to earthquake ground motion has long been a subject of multidisciplinary interest and research. In most versions of seismic intensity scales, human perceptions and behavior are one component of the assignment of intensity. Public health research has shown that actions taken during earthquakes have a significant impact...

Mercury (Hg) is a pervasive environmental pollutant and contaminant of concern for both people and wildlife that has been a focus of environmental remediation efforts for decades. A growing body of literature has motivated calls for revising Hg consumption advisories to...