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Freshwater impoundments, like all inland aquatic systems, are sites of intense carbon processing and transport. They receive carbon in several forms (coarsely aggregated into dissolved and particulate fractions of both inorganic and organic forms), convert one C species to anothe...

The Groundwater Technical Support Center (GWTSC) is part of the Groundwater, Watershed, and Ecosystem Restoration Division (GWERD), which is based in the Robert S. Kerr Environmental Research Center in Ada, Oklahoma. The GWERD is a research division of EPA&rsquo;s National Risk M...

A presentation to be given at the 2018 APHL Annual Meeting and Twelfth Government Environmental Laboratory Conference. Harmful algal blooms or HABs are overgrowth of cyanobacteria in water bodies. These bacteria produce several harmful toxins (called cyanotoxins) that have detri...

Harmful algal blooms (HABs) were a topic of great interest at the 2018 ASLO Summer Meeting in Victoria, B.C., Canada (Fig. 1). This was no surprise, since HABs may become &ndash; and already are in some areas &ndash; the greatest water quality threat to public health and aquatic ...

Benthic invertebrates support numerous ecosystem functions and services including shellfish production, energy flow to fishes, and biogeochemical cycles. The decline of marine biodiversity worldwide has raised concerns about effects on ecosystems. To examine biodiversity trends o...

While the effects of urbanization on stream ecosystems have been well-documented, little is known regarding the impact of burying streams within culverts. Our project aims to explore the ecological impacts of stream burial at a fine spatial scale. Two culverted urban streams in C...

Land use and environmental stressors, such as drought and deteriorating water infrastructure, can accelerate the depletion of freshwater resources that support humans and ecosystem services. As global demand for water and environmental stressors increase, the quality and availab...

Anthropogenic activities, such as mining/smelting, result in the release and accumulation of heavy metal(loid)s in soil, posing serious human health and ecological risks. Due to the persistence of metal(loid)s, not undergoing any chemical and biological degradation, they can only...

Biological assessments (surveying the presence, number, size and condition of fish, coral and other biota) provide important information about the health and integrity of coral reef ecosystems. Biological criteria are one means under the Clean Water Act (CWA) that managers can us...

Atmospheric deposition remains one of the largest loadings of nutrients to the Chesapeake Bay Watershed (CBW). The interplay between future climate and emission changes, however, will cause shifts in the future nutrient deposition abundance and regime (e.g., oxidized vs. reduced...

odotyrosine deiodinase (dehalogenase, IYD) catalyzes iodide recycling from monoiodotyrosine (MIT) and diiodotyrosine (DIT) and promotes retention of iodide in thyroid follicular cells. IYD has an important role in maintaining appropriate levels of thyroid hormones through conserv...

Natural capital accounting is a method of assessing the contribution of ecosystems to the economy, making the links between natural and economic systems more clear. While the System of Environmental-Economic Accounts&rsquo; Central Framework (developed by the U.N. and other inter...

Ecological restoration has traditionally been planned by evaluating ecosystem conditions, biodiversity, and production of ecosystem services, whereas evaluating the social benefits of restoration is uncommon. We present a decision-making approach to evaluate the social benefits o...

Forest disturbance regimes are beginning to show evidence of climate-mediated shifts associated with global climate change, and these patterns will likely continue due to continuing changes in environmental conditions. Tree growth is largely controlled by the physiological const...

The nation&rsquo;s economic accounts provide objective, regular, and standardized information routinely relied upon by public and private decision makers. But they are incomplete. The U.S. and many other nations currently do not account for the natural capital &mdash; such as the...

The nation&rsquo;s economic accounts provide objective, regular, and standardized information routinely relied upon by public and private decision makers. But they are incomplete. The U.S. and many other nations currently do not account for the natural capital &mdash; such as the...

Biogenic isoprene emissions play a very important role in atmospheric chemistry. They are strongly dependent on various environmental conditions, such as temperature, solar radiation, plant water stress, ambient ozone and CO2 concentrations, and soil moisture. Current biogenic ...

This paper addresses United States Environmental Protection Agency (EPA) operational and research challenges for the next decade in the utilization of space-based observations for the assessment of terrestrial properties affecting land, water, and air resources, and human health....

Landforms &ndash; specifically hillslope forms and resulting processes &ndash; couple terrestrial and aquatic systems. In urban watersheds, soil is commonly moved and shaped to accomplish land and water management objectives of residents and municipal agencies. Here, we ask, how ...

Estuaries are dynamic transition zones linking freshwater and oceanic habitats. These productive ecosystems are threatened by a variety of stressors including human modification of coastal watersheds. In this study we examined potential linkages between estuarine condition and...

Poly- and perfluoroalkyl substances (PFASs) have been produced since the 1940s for use in commercial and industrial applications, including water repellant coatings, surfactants, and vinyl polymerization. PFASs demonstrate remarkable environmental persistence and bioaccumulative ...

AQUATOX is an ecosystem simulation model that predicts the environmental fate of various pollutants, such as excess nutrients and organic chemicals, and their effects on aquatic ecosystems, including fish, invertebrates, and aquatic plants. AQUATOX is one of the preeminent tools ...

Increased human development along the coast and the subsequent increased delivery of excess nutrients to estuarine waterbodies can have combined deleterious effects on salt marsh ecosystems. An increasingly popular shoreline stabilization technique is the use of a living shorelin...

Salt marshes may act either as greenhouse gas (GHG) sources or sinks depending on hydrological conditions, vegetation communities, and nutrient availability. In recent decades, eutrophication has emerged as a major driver of change in salt marsh ecosystems. An ongoing fertilizati...

A detailed understanding of the distribution and fate of atmospheric sulfur (SOx) and reactive nitrogen compounds (NOy and NHx) is desirable given their role in determining tropospheric acidic substances and particulate matter budgets and potential nutrient loading effects in sen...