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Ecological resources for fishes in stream food webs shift over space and time, providing a complex template of available resources that can be used for growth. We tracked water temperature in conjunction with young-of-year Coho Salmon size, growth, and diet in 2 streams with contrasting thermal regimes: a groundwater stream...

The seasonal and inter-annual variability of flow presence and water temperature within headwater streams of the Great Basin of the western United States limit the occurrence and distribution of coldwater fish and other aquatic species. To evaluate changes in flow presence and water temperature during seasonal dry periods, we developed...

Winter cover crops such as barley, rye, and wheat help to improve soil structure by increasing porosity, aggregate stability, and organic matter, while reducing the loss of agricultural nutrients and sediments into waterways. The environmental performance of cover crops is affected by choice of species, planting date, planting...

Catalina Basin, located within the southern California Inner Continental Borderland (ICB), is traversed by two active submerged fault systems that are part of the broader North America-Pacific plate boundary: the San Clemente fault (along with a prominent splay, the Kimki fault) and the Catalina fault. Previous studies have suggested that...

Managed and wild pollinators are critical components of agricultural and natural systems. Despite the well-known value of insect pollinators to U.S. agriculture, Apis mellifera (Linnaeus, 1758; honey bees) and wild bees currently face numerous stressors that have resulted in declining health. These declines have engendered support for pollinator conservation efforts...

Executive SummaryA field investigation intended to measure the potential for erosion of sediments beside the American and Sacramento Rivers near Sacramento, California, is described. The study featured two primary components: (1) drilling and soil sampling to reveal lithology, down to depths matching the local river thalweg, where possible, and (2)...

Lake water levels are often managed in shallow lakes in order to improve water quality and promote aquatic vegetation that presumably benefits water birds. We aimed to understand whether waterbird abundance and species richness during fall migrations were positively influenced by managed lake water levels at 32 shallow lakes over...

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...