All Publications

Increases in fluxes of nitrogen (N) and phosphorus (P) in the environment have led to negative impacts affecting drinking water, eutrophication, harmful algal blooms, climate change, and biodiversity loss. Because of the importance, scale, and complexity of these issues, it may be useful to consider methods for prioritizing nutrient research in representative drainage basins within a regional or n

Per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals with a nondegradable fluorinated carbon backbone that have been incorporated in countless industrial and commercial applications. Because PFAS are nondegradable, they have been detected in all environmental media, indicating extensive global contamination. The unique physiochemical properties of PFAS and their complex interactions

More than 20,000 horizontal wells have been drilled and hydraulically fractured in the Eagle Ford Group since the discovery well in 2008, but a considerable amount of undiscovered petroleum remains. Recently, drilled wells have been hydraulically fractured with an average of nearly 13 million gallons of water and 16 million lb of sand, yielding a million or more gallons of produced water. To infor

BackgroundThe process known as ecological diffusion emerges from a first principles view of animal movement, but ecological diffusion and other partial differential equation models can be difficult to fit to data. Step-selection functions (SSFs), on the other hand, have emerged as powerful practical tools for ecologists studying the movement and habitat selection of animals.MethodsSSFs typically i

Sediments surrounding hydrothermal vents are important transition spaces between hydrothermal and pelagic environments. These sediments accumulate through diverse processes that include water column plume fallout, volcanic ash deposition, and mass wasting of hydrothermal chimneys and mounds superimposed upon background sedimentation which may originate from pelagic, terrestrial, and volcanic sourc

This study aimed to gain insight into the influence of storage time and temperature on fatty acid (FA) signatures of biopsies of marine mammal adipose/blubber tissues. To examine storage effects, biopsy-type slices from larger pieces of adipose tissues from 2 polar bears Ursus maritimus were stored at either -20 or -80°C and subsequently analyzed for fatty acid composition initially (before storag

LANDFIRE (LF) has been producing periodic spatially explicit vegetation change maps (i.e., LF disturbance products) across the entire United States since 1999 at a 30 m spatial resolution. These disturbance products include data products produced by various fire programs, field-mapped vegetation and fuel treatment activity (i.e., events) submissions from various agencies, and disturbances detected

Mass mortality of the dominant coral reef herbivore Diadema antillarum in the Caribbean in the early 1980s contributed to a persistent phase shift from coral- to algal-dominated reefs. In 2022, a scuticociliate most closely related to Philaster apodigitiformis caused further mass mortality of D. antillarum across the Caribbean, leading to >95% mortality at affected sites. Mortality was also report

Risks posed by environmental exposure to chemicals are routinely assessed to inform activities ranging from environmental status reporting to authorization and registration of chemicals for commercial uses. Environmental risk assessment generally relies on two key values generated from exposure data and ecotoxicity data. Data sets of measured concentrations of chemicals in environmental matrices,

Grass carp (Ctenopharyngodon idella, Val.) is an invasive species in the Laurentian Great Lakes region with the potential for damaging the lake ecosystem and harming the region's economy. Grass carp spawning was documented in the Sandusky River, Ohio, in 2015 through targeted egg sampling. Continued egg sampling in the Sandusky River suggested that grass carp spawning is related to discharge and w

The U.S. Geological Survey is working with Federal land management agencies to develop a series of science syntheses to support environmental effects analyses that agencies conduct to comply with the National Environmental Policy Act (NEPA). This report synthesizes science information about the potential effects of culverts on stream connectivity and subsequent effects on fish. We conducted a stru

Several recent generation global-climate models were found to have anomalously high climate sensitivities and may not be useful for certain applications. Four approaches for developing ensembles of climate projections for applications that address this issue are:Using an “all models” approach;Screening using equilibrium climate sensitivity and (or) transient climate response;Bayesian model averagi