<< Previous

Next >>

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...

Excess deposition (including both wet and dry deposition) of nitrogen and sulfur are detrimental to ecosystems. Recent studies have investigated the spatial patterns and temporal trends of nitrogen and sulfur wet deposition, but few studies have focused on dry deposition due to t...

The St. Louis River represents a complex natural resource management problem. Current ecosystem management decisions must address extensive sediment remediation and habitat restoration goals for the lower river and associated port, as well as recreational users who value differen...

Morphological Spatial Pattern Analysis (MSPA) has been widely adopted by landscape ecologists over the past decade. A few examples of its many uses include: 1) quantifying landscape indicators and fragmentation in continental forest assessments, 2) explaining interior-exterior p...

Both rural and urban development can lead to accelerated gully erosion. Quantify gully erosion is challenging in environments where gullies are rapidly repaired and in urban areas where microtopographic complexity complicates the delineation of contributing areas. This study used...

Freshwater fish are ecologically important in stream ecosystems, and they provide significant value to humans. Historically, the streams and rivers of southern New England supported moderately diverse and abundant assemblages of native fishes. Currently, these habitats are impact...

Background: The three Jackson Lakes within the Bayou Chico Watershed in NW FL, USA were formed at different times from abandoned sand pits. The lakes experienced inundation with marine water during Hurricane Ivan 2004 and, despite their proximity and similar physical structures, ...

The area burned by wildland fires (prescribed and wild) across the contiguous United States (U.S.) has expanded by nearly 50% and now averages 2 million hectares per year. Such fires are estimated to cause 8,000 deaths per year and are monetized as having a ~$450 billion impact ...

In population-dense Massachusetts (USA) acquiring historical wetlands for ecological restoration efforts can be difficult and expensive. Retiring cranberry bogs create a rare opportunity to restore historical wetlands. Environmental managers face important decisions about how to ...

Modelling gully erosion in urban areas is challenging due to difficulties with equifinality and parameter identification, which complicates quantification 0of management impacts on runoff and sediment production. We calibrated a model (AnnAGNPS) of an ephemeral gully network that...

The grand challenge of our time, in the face of the increasing impact of humans on the environment and climate, is to derive actionable knowledge to ensure sustainable use of marine and coastal resources and a healthy global society.This grand challenge requires a focus on these ...

An interdisciplinary working group comprised of experts in economics, accounting, and the natural sciences has worked to develop proof-of-concept natural capital accounts (land, water, and ecosystems) for the United States using existing data sources. With support from the Nation...

Ecological and human health impairments related to excess nitrogen (N) remain widespread in U.S. streams and rivers despite recent efforts to reduce N loading. Many studies have quantified the relationship between N inputs to watersheds and stream N export in terms of mass loads....

This report will be a chapter in an updated Riparian BMP manual developed by the State of WA Fish and Wildlife Dept. Jana Compton and I were asked to contribute the chapter on nutrients in riparian ecosystems based on experience and research in riparian systems. The document is...

The health of estuarine ecosystems is often influenced by hydraulic and nutrient loading from upstream watersheds. This study analyzed a long-term (1979~2014) water quality and discharge data set collected from four adjacent coastal watersheds in south Florida where land and wat...

Nitrogen (N) and phosphorus (P) nutrient discharge regulations are becoming more stringent with increased environmental impacts, especially in surface water bodies. Many wastewater treatment plants (WWTPs) have been equipped with the necessary nutrient removal technologies to mee...

This is a briefing to the new director of Tillamook Estuaries Partnership to 1) summarize recent research on nutrients, fecal bacteria, acidification, watershed modeling, and shellfish habitats, and 2) introduce a new project to assess people's recreational use of estuarine ecosy...

Planning for a sustainable future should include an accounting of services currently provided by ecosystems such as erosion control. Retention of soil not only maintains but improves soil fertility, improves water retention, and decreases sedimentation in streams and rivers ther...

Direct photolysis is an important degradation pathway for organic compounds bearing sunlight-absorbing chromophores in aquatic systems. An ever-growing body of process science underlying direct photolysis transformation pathways provides the basis for the development of predictiv...

Freshwater ecosystems harbor a rich diversity of species and habitats and also provide critical resources to people. The condition of these ecosystems can be degraded by numerous environmental stressors, such as increases in pollution, habitat alteration, introduction of invasive...

This seminar will present an overview of EPA&rsquo;s Visualizing Ecosystem Land Management Assessments (VELMA) model and its applications in the Puget Sound Basin. Topics will include a description of how VELMA simulates the interaction of hydrological and biogeochemical processe...

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. Despite this, there are few studies conducted to demonstrate the importance ...

Riparian reforestation is a common restoration action in urban streams, but relatively little is known about the influence of local riparian vegetation in the face of watershed-scale urban land cover. Allochthonous organic matter and benthic algae are important basal energy resou...

Much of the literature and attention on the analysis of ecological change is focused on detecting temporal trends at single sites. Of equal importance is the change in spatial condition across the landscape. For example, are there more hypereutrophic lakes in the U.S. now than th...