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Drinking water supply wells can be contaminated by a broad range of waterborne pathogens. However, groundwater assessments frequently measure microbial indicators or a single pathogen type, which provides a limited characterization of potential health risk. This study assessed contamination of wells by testing for viral, bacterial, and protozoan pathogens and...

The collective set of decisions involved with the restoration of degraded wetlands is often more complex than considering only ecological responses and outcomes. Restoration is commonly driven by a complex interaction of social, economic, and ecological factors representing the mandate of resource stewards and the values of stakeholders. The authors...

Volcanic eruptions can affect landscapes in many ways and consequently alter erosion and the fluxes of water and sediment. Hydrologic and geomorphic responses to volcanic disturbances are varied in both space and time, and, in some instances, can persist for decades to centuries. Understanding the broad context of how landscapes...

The Vermont Department of Health and the U.S. Geological Survey analyzed the concentrations of chloride in groundwater samples collected from 4,319 domestic wells across Vermont between 2011 and 2018. Ninety of these wells were sampled twice and the remaining 4,229 were sampled once. This sample size represents approximately 4 percent...

Groundwater age distributions developed from carbon-14 (14C), tritium (3H), and helium-4 (4He) concentrations, along with aquifer hydrologic position, water type, and redox conditions, were compared to geogenic contaminants of concern (GCOC) from 252 public-supply wells in six Atlantic and Gulf Coastal Plain unconsolidated-sediment aquifers. Concentrations of one or more...

Because groundwater recharge in dry regions is generally low, arid and semiarid environments have been considered well‐suited for long‐term isolation of hazardous materials (e.g., radioactive waste). In these dry regions, water lost (transpired) by plants and evaporated from the soil surface, collectively termed evapotranspiration (ET), is usually the primary discharge...

Ecosystem accounts, as formalized by the System of Environmental-Economic Accounting Experimental Ecosystem Accounts (SEEA EEA), have been compiled in a number of countries, yet there have been few attempts to develop them for the U.S. We explore the potential for U.S. ecosystem accounting by compiling ecosystem extent, condition, and...

With the global-scale loss of biodiversity, current restoration programs have been often required as part of conservation plans for species richness and ecosystem integrity. The restoration of pelagic-oriented cisco (Coregonus artedi) has been an interest of Lake Michigan managers because it may increase the diversity and resilience of the fish...

Changes in population, agricultural development and practices (including shifts to more water-intensive crops), and climate variability are increasing demands on available water resources, particularly groundwater, in one of the most productive agricultural regions in the Southwest—the Rincon and Mesilla Valley parts of Rio Grande Valley, Doña Ana and Sierra Counties,...

Groundwater in eastern Abu Dhabi in the United Arab Emirates is an important resource that is widely used for irrigation and domestic supplies in rural areas. The U.S. Geological Survey and the Environment Agency—Abu Dhabi cooperated on an investigation to integrate existing hydrogeologic information and to answer questions about regional...

Five species of sea turtle rely on Florida’s coastal and nearshore habitats for nesting during the summer months and foraging throughout the year (Figure 1). - Loggerhead turtles, named for their large, block-shaped heads with strong jaw muscles for crushing benthic invertebrates, are the most common sea turtle species...

The U.S. Geological Survey’s (USGS) Modular Ground-Water Flow Model (MODFLOW-2005) is a computer program that simulates groundwater flow by using finite differences. The MODFLOW-2005 framework uses a modular design that allows for the easy development and incorporation of new features called processes and packages that work with or modify inputs...

Despite decades of research into air and stream temperature dynamics, paired air-water annual temperature signals have been underutilized to characterize watershed processes. Annual stream temperature dynamics are useful in classifying fundamental thermal regimes and can enhance process-based interpretation of stream temperature controls, including deep and shallow groundwater discharge, when paired...

Relatively minor amounts of methane, a potent greenhouse gas, are currently emitted from the oceans to the atmosphere, but such methane emissions have been hypothesized to increase as oceans warm. Here, we investigate the source, distribution, and fate of methane released from the upper continental slope of the U.S....

The likelihood that fish will initiate spawning, spawn successfully, or skip spawning in a given year is conditioned in part on availability of energy reserves. We evaluated the consequences of spatial heterogeneity in thermal conditions on the energy accumulation and spawning potential of migratory bull trout (Salvelinus confluentus) in a...

Lake Michigan benthic macrofauna have been studied for almost a century, allowing for a unique analysis of long-term changes in community structure. We examined changes in abundances of three major taxonomic groups of benthic macroinvertebrates (Diporeia, Oligochaeta, and Sphaeriidae) in southern Lake Michigan from 1931-2015, and identified the most likely...

Increasing our understanding of invasive species is important because of the negative impacts they can have on the economies and ecosystems of invaded regions. There is growing interest in how environmental variability (e.g. temperature) and stochastic invasion events (e.g. founder effects) affect the genetic composition of populations of invasive species....

River corridors store, convey, and process nutrients from terrestrial and upstream sources, regulating delivery from headwaters to estuaries. A consequence of chronic excess nitrogen loading, as supported by theory and field studies in specific areas, is saturation of the biogeochemically-mediated nitrogen removal processes that weakens the capacity of the river...

Much attention has been placed on the role that under-roadway culverts may have in inhibiting upstream fish movement because of altered hydrology and unsuitable conditions for accessing or swimming through the culvert. Other culvert effects related to habitat alterations or disturbance to macroinvertebrate communities have received relatively little attention. Entities...

Groundwater hydrology and geochemistry within the tidal Anacostia River watershed of Washington, D.C. are related to natural and human influences. The U.S. Geological Survey, in cooperation with the District Department of Energy & Environment, began investigating the hydrogeology and groundwater quality of the watershed in 2002. Lithologic coring, groundwater-level and...

Chemical contaminants are a threat to the Chesapeake Bay watershed, with mercury (Hg) among the most prevalent causes of impairment. Despite this, large-scale patterns of Hg concentrations, and the potential risks to fish, wildlife, and humans across the watershed, are poorly understood. We compiled fish Hg data from state monitoring...

PremiseDetermining which traits characterize strategies of coexisting species is important to developing trait‐based models of plant communities. First, global dimensions may not exist locally. Second, the degree to which traits and trait spectra constitute independent dimensions of functional variation at various scales continues to be refined. Finally,...

Temperature has a fundamental influence on physical, chemical and biological processing in aquatic ecosystems. River temperatures respond to a diverse array of drivers including air temperature, streamflow, and thermal inputs, but the physical template has been shown to play a significant role in structuring spatial and temporal variation in water...

This is the third and final report in a series that describe the groundwater resources of the Hualapai Indian Reservation. These reports document the findings of a comprehensive groundwater study conducted on the reservation and adjacent areas from 2015 through 2018 by the U.S. Geological Survey in cooperation with the...

Respiratory disease is a key factor affecting the conservation and recovery of bighorn sheep (Ovis canadensis ) populations. Innovative, minimally invasive tools such as gene transcription–based diagnostics have the potential to improve our understanding of the broad range of factors that can affect the health of wild sheep. Evaluation of transcript...