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Articles 1 - 17 of 17

Full-Text Articles in Physical Sciences and Mathematics

Episodic Stream Acidification Caused By Atmospheric Deposition Of Sea Salts At Acadia National Park, Maine, United States, Richard H. Heath, Jeffrey S. Kahl, Stephen A. Norton, Ivan J. Fernandez Mar 2015

Episodic Stream Acidification Caused By Atmospheric Deposition Of Sea Salts At Acadia National Park, Maine, United States, Richard H. Heath, Jeffrey S. Kahl, Stephen A. Norton, Ivan J. Fernandez

Ivan J. Fernandez

Major episodic acidifications were observed on several occasions in first-order brooks at Acadia National Park, Mount Desert Island, Maine. Short-term declines of up to 2 pH units and 130-mu-eq L-1 acid-neutralizing capacity were caused by HCl from soil solutions, rather than by H2SO4 or HNO3 from precipitation, because (1) SO4 concentrations were constant or decreased during the pH depression, (2) Cl concentrations were greatest at the time of lowest pH, and (3) Na:Cl ratios decreased from values much greater than those in precipitation (a result of chemical weathering), to values equal to or less than those in precipitation. Dilution, increases …


Tb138: Variability Factors Involved With Land Application Of Papermill Sludge, Charles R. Kraske, Ivan J. Fernandez Mar 2015

Tb138: Variability Factors Involved With Land Application Of Papermill Sludge, Charles R. Kraske, Ivan J. Fernandez

Ivan J. Fernandez

The goal of this case study was to assess two components of variability associated with the land application of papermill sludge. These included (1) changes occurring within a temporary sludge stockpile, and (2) spatial variability of application to the site. Understanding the magnitude of such changes will assist in accounting for variability inherent in such land application operations.


Maine’S Climate Yesterday, Today, And Tomorrow, George L. Jacobson, Ivan J. Fernandez, Paul A. Mayewski, Catherine V. Schmitt Mar 2015

Maine’S Climate Yesterday, Today, And Tomorrow, George L. Jacobson, Ivan J. Fernandez, Paul A. Mayewski, Catherine V. Schmitt

Ivan J. Fernandez

Recent evidence suggests that climate change is occurring at an accelerated rate as a result of human-induced greenhouse gas emissions and associated pollutants. Based on a recently completed study, the authors describe the changes Maine’s climate is likely to undergo over the next century. They suggest that while reduction of greenhouse gases is crucial, Maine needs to be prepared to adapt to the impact that our already changing climate will have on various ecosystems and economic sectors within the state


Tb178: Methods For Evaluating Carbon Fractions In Forest Soils: A Review, Jennifer L. Evans, Ivan J. Fernandez, Lindsey E. Rustad, Stephen A. Norton Mar 2015

Tb178: Methods For Evaluating Carbon Fractions In Forest Soils: A Review, Jennifer L. Evans, Ivan J. Fernandez, Lindsey E. Rustad, Stephen A. Norton

Ivan J. Fernandez

This publication was developed as part of an effort to evaluate the existing methodologies for determining carbon fractions in soils that might be applied to the question of forest soil C sequestration. A great deal of research has been done on this topic although often focused on agronomic soils. Forest land managers will be increasingly interested in identifying methods to monitor and to evaluate the effects of forest practices on soil C reserves. As well researchers are interested in this and the logical linkages to N cycling. Ultimately practical methods that can be widely utilized will be needed; these may …


Soil Denitrification Fluxes From Three Northeastern North American Forests Across A Range Of Nitrogen Deposition, Jennifer Morse, Jorge Durán, Fred Beall, Eric Enanga, Irena Creed, Ivan Fernandez, Peter Groffman Mar 2015

Soil Denitrification Fluxes From Three Northeastern North American Forests Across A Range Of Nitrogen Deposition, Jennifer Morse, Jorge Durán, Fred Beall, Eric Enanga, Irena Creed, Ivan Fernandez, Peter Groffman

Ivan J. Fernandez

In northern forests, large amounts of missing N that dominate N balances at scales ranging from small watersheds to large regional drainage basins may be related to N-gas production by soil microbes. We measured denitrification rates in forest soils in northeastern North America along a N deposition gradient to determine whether N-gas fluxes were a significant fate for atmospheric N inputs and whether denitrification rates were correlated with N availability, soil O2 status, or forest type. We quantified N2 and N2O fluxes in the laboratory with an intact-core method and monitored soil O2, temperature and moisture in three forests differing …


Tb196: Temperature, Soil Moisture, And Streamflow At The Bear Brook Watershed In Maine (Bbwm), Ivan J. Fernandez, Joseph E. Karem, Stephen A. Norton, Lindsey E. Rustad Mar 2015

Tb196: Temperature, Soil Moisture, And Streamflow At The Bear Brook Watershed In Maine (Bbwm), Ivan J. Fernandez, Joseph E. Karem, Stephen A. Norton, Lindsey E. Rustad

Ivan J. Fernandez

The Bear Brook Watershed in Maine is a whole-ecosystem chemical manipulation initiated in 1987 to study the effects of acid deposition on forests and surface waters. The focus of this research was to understand the biogeochemical response of watersheds with emphasis on chemistry and hydrology. In 2001 a program was initiated to provide more detailed measurements of temperature and moisture to examine critical linkages amongst chemical, biological, and physical processes that ultimately work together to define ecosystem function. The purpose of this publication is to provide data from the initial phase of soil temperature, air temperature, and soil moisture measurements …


Tb119: Selected Relationships For Trace Metals In Maine Low Elevation Spruce-Fir Forest Floors, Ivan J. Fernandez, Miroslaw M. Czapowskyj Mar 2015

Tb119: Selected Relationships For Trace Metals In Maine Low Elevation Spruce-Fir Forest Floors, Ivan J. Fernandez, Miroslaw M. Czapowskyj

Ivan J. Fernandez

Results from the analysis of trace metals in the forest floor from three study areas northern Maine commercial spruce-fir stands showed significant, positive correlations were frequently evident between ash-free concentrations of Individual pairs of trace metals. Only Pb concentrations at one location were found to vary significantly among soil drainage classes. Overall, ash-free trace metal concentrations were less than what has been found at sites receiving high loadings of atmospheric deposition in the Northeast. Few historical data are available to adequately determine if Maine forest floor trace metal concentrations are greater than the natural levels expected in commercial forests, but …


Tb118: Composition Of Precipitation At The National Atmospheric Deposition Program/National Trends Network (Nadp/Ntn) Site In Greenville, Maine, Ivan J. Fernandez, Llew Wortman, Stephen A. Norton Mar 2015

Tb118: Composition Of Precipitation At The National Atmospheric Deposition Program/National Trends Network (Nadp/Ntn) Site In Greenville, Maine, Ivan J. Fernandez, Llew Wortman, Stephen A. Norton

Ivan J. Fernandez

This report presents results of the analyses of samples collected at the Greenville, Maine, NADP station. The Greenville NADP/NTN station is in Piscataquis County at longitude 69°39'52" and latitude 4S°29'23" at approximately 322 meters elevation.


Tb162: Red Maple And White Pine Litter Quality: Initial Changes With Decomposition, Mairin T. Delaney, Ivan J. Fernandez, Jeffrey A. Simmons, Russel D. Briggs Mar 2015

Tb162: Red Maple And White Pine Litter Quality: Initial Changes With Decomposition, Mairin T. Delaney, Ivan J. Fernandez, Jeffrey A. Simmons, Russel D. Briggs

Ivan J. Fernandez

The specific objectives of this study were (a) to define the organic and inorganic composition of foliar litter from red maple (Acer rubrum L.) and white pine (Pinus strobus L.), and (b) to determine the shifts in the organic and inorganic composition of these two litter types during the initial stages of decomposition. These two species were chosen because of their prominence in the northeastern U.S. and the contrast they afforded in litter quality characteristics which have a strong influence on litter decomposition.


Tb105: The Composition Of Equilibrium Soil Solutions From Forest Soil B Horizons, Ivan J. Fernandez, Roland A. Struchtemeyer Mar 2015

Tb105: The Composition Of Equilibrium Soil Solutions From Forest Soil B Horizons, Ivan J. Fernandez, Roland A. Struchtemeyer

Ivan J. Fernandez

The objective of the present study was to evaluate the composition of B horizon equilibrium soil solutions from selected Maine forest soils. The B horizon was chosen for evaluation because it (1) best expressed the weathering processes active in the soil, (2) occupied the greatest volume of the solum, (3) had the most complex chemistry of the major horizons, and (4) provided the major corridor in forested ecosystems for subsurface flow and chemical alteration of ground waters.


Tb200: Carbon And Nutrients In Maine Forest Soils, Ivan J. Fernandez Mar 2015

Tb200: Carbon And Nutrients In Maine Forest Soils, Ivan J. Fernandez

Ivan J. Fernandez

Recent public concerns surrounding climate change and greenhouse gas emissions have resulted in a lively debate about approaches to fossil fuel offsets and carbon (C) sequestration in forests. The forest community sees opportunities for the intensification of the use of forests for markets ranging from forest products, such as fuel or fuel feedstock, to a range of new bioproducts. This report provides initial insights from an ongoing effort to synthesize forest soils data for Maine. The specific objectives presented here were (1) to develop descriptive statistics for C and measures of available forms of the essential nutrients N, P, and …


Tb195: Element Concentrations In Maine Forest Vegetation And Soils, Chandra J. Mcgee, Ivan J. Fernandez, Stephen A. Norton, Constance S. Stubbs Mar 2015

Tb195: Element Concentrations In Maine Forest Vegetation And Soils, Chandra J. Mcgee, Ivan J. Fernandez, Stephen A. Norton, Constance S. Stubbs

Ivan J. Fernandez

Bioaccumulation of trace metals in plant tissues can present a health risk to wildlife, and potentially to humans. The Passamaquoddy Tribe in Maine was concerned about health risks of cadmium (Cd) because of a health advisory for moose liver and kidney consumption due to high Cd levels. In addition to Cd, this study evaluated concentrations of aluminum (Al), calcium (Ca), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), nickel (Ni), phosphorus (P), lead (Pb), and zinc (Zn) in four common terrestrial moose-browse species, associated forest soils, and two species of aquatic vegetation on Passamaquoddy tribal land in eastern …


Collaborative Research: Interactive Effects Of Chronic N Deposition, Acidification, And Phosphorus Limitation On Coupled Element Cycling In Streams, Kevin S. Simons, Ivan J. Fernandez, Stephen A. Norton Mar 2015

Collaborative Research: Interactive Effects Of Chronic N Deposition, Acidification, And Phosphorus Limitation On Coupled Element Cycling In Streams, Kevin S. Simons, Ivan J. Fernandez, Stephen A. Norton

Ivan J. Fernandez

The overarching goal of this project is to understand how chronic acidification and nitrogen enrichment of watersheds influences coupled biogeochemical cycling in streams. Embedded in the project were two primary research elements: 1) examining nitrogen satuartion and the extent of coupling between nitrogen and phosphorus cycling and 2) resolving the interactions among acidification, phosphorus bioavailability and biotic demand for nitrogen and phosphorus. The research involved a series of stable isotope tracer experiments to document nitrogen uptake under ambient and elevated phosphrous conditions and examination of a suite of key microbial processes (denitrification, decomposition, microbial enzyme activity) at two whole-watershed experiment …


Maine's Climate Future: An Initial Assessment, George Jacobson, Ivan Fernandez, Paul Mayewski, Catherine Schmitt Mar 2015

Maine's Climate Future: An Initial Assessment, George Jacobson, Ivan Fernandez, Paul Mayewski, Catherine Schmitt

Ivan J. Fernandez

Earth’s atmosphere is experiencing unprecedented changes that are modifying global climate. Discussions continue around the world, the nation, and in Maine on how to reduce and eventually eliminate emissions of carbon dioxide (CO2), other greenhouse gases, and other pollutants to the atmosphere, land, and oceans. These efforts are vitally important and urgent. However, even if a coordinated response succeeds in eliminating excess greenhouse gas emissions by the end of the century, something that appears highly unlikely today, climate change will continue, because the elevated levels of CO2 can persist in the atmosphere for thousands of years to come.

In late …


Tb126: Vertical Trends In The Chemistry Of Forest Soil Microcosms Following Experimental Acidification, Ivan J. Fernandez Mar 2015

Tb126: Vertical Trends In The Chemistry Of Forest Soil Microcosms Following Experimental Acidification, Ivan J. Fernandez

Ivan J. Fernandez

A soil microcosm experiment was conducted (a) to compare dilute H2SO4, NH4NO3 fertilizer, and prilled S as possible experimental soil-acidifying treatments and (b) to observe soil chemical response to simulated throughfall and acidifying treatments. Simulated throughfall had a significant effect on soil chemistry, resulting in increased exchangeable bases and pH in the mineral soil horizons but little effect on the O horizon. Of the acidification treatments only simulated acid rain had significant effects on soil chemistry when compared to the control and the dry treatments. This reflected the relatively slow dissolution rate of the dry treatments coupled with the short …


Tb134: A Laboratory Study To Assess Methods For Predicting Ph Change Of Ash Amended Forest Soils, Yvonne Unger, Ivan Fernandez Mar 2015

Tb134: A Laboratory Study To Assess Methods For Predicting Ph Change Of Ash Amended Forest Soils, Yvonne Unger, Ivan Fernandez

Ivan J. Fernandez

The objective of this study was to compare several commonly used lime requirement tests and soil capacity factors for their ability to predict pH change following wood-ash amendment. The ability to predict pH change is important because it is one of the criteria used to prescribe rates of ash amendment to forest soils.


Tb164: Precipitation Chemistry At The Greenville, Maine, Nadp/Ntn Station, Ivan Fernandez, Llew Wortman Mar 2015

Tb164: Precipitation Chemistry At The Greenville, Maine, Nadp/Ntn Station, Ivan Fernandez, Llew Wortman

Ivan J. Fernandez

This report details results from the Greenville, Maine, NADP/NTN site supported by the Maine Agricultural and Forest Experiment Station. The site is located in Piscataquis County at 69°39'52" longitude and 45°29'23" latitude at approximately 322 m elevation. The site consists of a single Aerochem Metrics® Automatic Sensing Wet/Dry Precipitation Collector that provides samples for chemical analysis and a Belfort® Recording Rain Gage and Event Recorder for accurate determinations of precipitation volume. Samples are collected every Tuesday morning 52 weeks a year.