Environmental Engineering Commons^™

Estimating Mineral Weathering Rates In Catskills Watersheds, Chris E. Johnson

Civil and Environmental Engineering

No abstract provided.

Is Horizon Sampling More Powerful Than Depth Sampling?, Chris E. Johnson

Civil and Environmental Engineering

No abstract provided.

Soil Chemistry Response To Wollastonite (Casio3) Addition At Hubbard Brook, Chris E. Johnson

Civil and Environmental Engineering

No abstract provided.

Recovery Of Sensitive Watersheds In The Northeastern United States From Chronic Acidification: The Role Of Soil Chemistry, Chris E. Johnson

Civil and Environmental Engineering

No abstract provided.

Science And Society: The Role Of Long-Term Studies In Environmental Stewardship, Charles T. Driscoll, Kathleen F. Lambert, F. Stuart Chapin, David J. Nowake, Thomas A. Spies, Frederick J. Swanson, David B. Kittredge, Clarisse M. Hart

Civil and Environmental Engineering

Long-term research should play a crucial role in addressing grand challenges in environmental stewardship. We examine the efforts of five Long Term Ecological Research Network sites to enhance policy, management, and conservation decisions for forest ecosystems. In these case studies, we explore the approaches used to inform policy on atmospheric deposition, public land management, land conservation, and urban forestry, including decisionmaker engagement and integration of local knowledge, application of models to analyze the potential consequences of policy and management decisions, and adaptive management to generate new knowledge and incorporate it into decisionmaking. Efforts to enhance the role of long-term research …

Nutrient Supply And Mercury Dynamics In Marine Ecosystems: A Conceptual Model, Charles T. Driscoll, Celia Y. Chen, Chad R. Hammerschmidt, Robert P. Mason, Cynthia C. Gilmour, Elsie M. Sunderland, Ben K. Greenfield, Kate L. Buckman, Carl H. Lamborg

Civil and Environmental Engineering

There is increasing interest and concern over the impacts of mercury (Hg) inputs to marine ecosystems. One of the challenges in assessing these effects is that the cycling and trophic transfer of Hg are strongly linked to other contaminants and disturbances. In addition to Hg, a major problem facing coastal waters is the impacts of elevated nutrient, particularly nitrogen (N), inputs. Increases in nutrient loading alter coastal ecosystems in ways that should change the transport, transformations and fate of Hg, including increases in fixation of organic carbon and deposition to sediments, decreases in the redox status of sediments and changes …

Soil Chemistry And The Recovery Of Sensitive Watersheds From Chronic Acidification, Chris E. Johnson

Civil and Environmental Engineering

No abstract provided.

Empirical Critical Loads Of Atmospheric Nitrogen Deposition For Nutrient Enrichment And Acidification Of Sensitive Us Lakes, Jill S. Baron, Charles T. Driscoll, John L. Stoddard, Eric E. Richer

Civil and Environmental Engineering

No abstract provided.

Using Equal‐Area Quadratic Splines To Compute Depth‐ Weighted Averages Of Soil Chemical Parameters, Chris E. Johnson, Jeremy Tamargo

Civil and Environmental Engineering

No abstract provided.

Accidental Releases Of Hazardous Materials And Relevance To Terrorist Threats At Industrial Facilities, Laura J. Steinberg, Nicholas Santella

Civil and Environmental Engineering

Hazardous material releases, some with serious consequences, are a common occurrence in the U.S. Of late, the hazards posed by releases caused by terrorist attacks or natural disasters have been of particular concern. Although terrorism directed at hazardous material handling industries within the U.S. has not yet resulted in a significant incident, there is much recent experience with serious accidental releases resulting from natural disasters. Case studies are developed from a number of recent natural disasters and severe weather events that resulted in large releases of hazardous materials. These case studies are used to illustrate parallels between the risks posed …

Spatial And Temporal Patterns Of Mercury Accumulation In Lacustrine Sediments Across The Laurentian Great Lakes Region, Paul E. Drevnick, Daniel R. Engstrom, Charles T. Driscoll, Edward B. Swain, Steven J. Balogh

Civil and Environmental Engineering

Data from 104 sediment cores from the Great Lakes and “inland lakes” in the region were compiled to assess historical and recent changes in mercury (Hg) deposition. The lower Great Lakes showed sharp increases in Hg loading c. 1850-1950 from point-source water dischargers, with marked decreases during the past half century associated with effluent controls and decreases in the industrial use of Hg. In contrast, Lake Superior and inland lakes exhibited a pattern of Hg loading consistent with an atmospheric source - gradual increases followed by recent (post-1980) decreases. Variation in sedimentary Hg flux among inland lakes was primarily attributed …

Effects Of Nitrogen Deposition And Empirical Nitrogen Critical Loads For Ecoregions Of The United States, Linda H. Pardo, Mike E. Fenn, Christine L. Goodale, Linda. H. Geiser, Charles T. Driscoll, Edith B. Allen, Jill S. Baron, Roland Bobbink, Williams D. Bowman, Christopher M. Clark, Bridget Emmett, Frank S. Gilliam, Tara L. Greaver, Sharon J. Hall, Erik A. Lilleskov, Lingli Liu, Jason A. Lynch, Knute J. Nadelhoffer, Steven S. Perakis, Molly J. Robin-Abbott, John L. Stoddard, Kathleen C. Weathers, Robin L. Dennis

Civil and Environmental Engineering

Human activity in the last century has led to a significant increase in nitrogen (N) emissions and atmospheric deposition. This N deposition has reached a level that has caused or is likely to cause alterations to the structure and function of many ecosystems across the United States. One approach for quantifying the deposition of pollution that would be harmful to ecosystems is the determination of critical loads. A critical load is defined as the input of a pollutant below which no detrimental ecological effects occur over the long-term according to present knowledge.

The objectives of this project were to synthesize …

Long-Term Trends From Ecosystem Research At The Hubbard Brook Experimental Forest, John L. Campbell, Charles T. Driscoll, Christopher Eagar, Gene E. Likens, Thomas G. Siccama, Chris E. Johnson, Timothy J. Fahey, Steven P. Hamburg, Richard T. Holmes, Amey S. Bailey, Donald C. Buso

Civil and Environmental Engineering

The Hubbard Brook Experimental Forest was established by the U.S. Forest Service in 1955 as a major center for hydrologic research in the Northeast. The Hubbard Brook Ecosystem Study originated 8 years later with the idea of using the small watershed approach to study element flux and cycling and the response of forest ecosystems to disturbance. Since that time, the research program at Hubbard Brook has expanded to include various physical, chemical and biological measurements collected by researchers from a number of cooperating institutions. Collaborative, long-term data are the keystone of the Hubbard Brook Ecosystem Study and have provided invaluable …

Mercury Contamination In Forest And Freshwater Ecosystems In The Northeastern United States, Charles T. Driscoll, Young-Ji Han, Celia Y. Chen, David C. Evers, Kathleen Fallon Lambert

Civil and Environmental Engineering

Eastern North America receives elevated atmospheric mercury deposition from a combination of local, regional, and global sources. Anthropogenic emissions originate largely from electric utilities, incinerators, and industrial processes. The mercury species in these emissions have variable atmospheric residence times, which influence their atmospheric transport and deposition patterns. Forested regions with a prevalence of wetlands and of unproductive surface waters promote high concentrations of mercury in freshwater biota and thus are particularly sensitive to mercury deposition. Through fish consumption, humans and wildlife are exposed to methylmercury, which markedly bioaccumulates up the freshwater food chain. Average mercury concentrations in yellow perch fillets …