Physical Sciences and Mathematics Commons^™

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

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

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

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

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

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

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

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

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

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

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

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

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

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.

Compactness Properties Of Commutators Of Bilinear Fractional Integrals, Árpád Bényi, Wendolin Damián, Kabe Moen, Rodolfo H. (Rodolfo Humberto) Torres

Mathematics Faculty Publications

Commutators of a large class of bilinear operators and multiplication by functions in a certain subspace of the space of functions of bounded mean oscillations are shown to be jointly compact. Under a similar commutation, fractional integral versions of the bilinear Hilbert transform yield separately compact operators.

Structural Distortion-Induced Magnetoelastic Locking In Sr2Iro4 Revealed Through Nonlinear Optical Harmonic Generation, D. H. Torchinsky, H. Chu, L. Zhao, N. B. Perkins, Y. Sizyuk, T. Qi, Gang Cao, D. Hsieh

Physics and Astronomy Faculty Publications

We report a global structural distortion in Sr₂IrO₄ using spatially resolved optical second and third harmonic generation rotational anisotropy measurements. A symmetry lowering from an I4₁/acd to I4₁/a space group is observed both above and below the Néel temperature that arises from a staggered tetragonal distortion of the oxygen octahedra. By studying an effective superexchange Hamiltonian that accounts for this lowered symmetry, we find that perfect locking between the octahedral rotation and magnetic moment canting angles can persist even in the presence of large noncubic local distortions. Our results …

Ship-Induced Solitary Riemann Waves Of Depression In Venice Lagoon, Kevin E. Parnall, Tarmo Soomere, Luca Zaggia, Artem Rodin, Giuliano Lorenzetti, John Rapaglia, Gian Marco Scarpaf

Biology Faculty Publications

We demonstrate that ships of moderate size, sailing at low depth Froude numbers (0.37–0.5) in a navigation channel surrounded by shallow banks, produce depressions with depths up to 2.5 m. These depressions (Bernoulli wakes) propagate as long-living strongly nonlinear solitary Riemann waves of depression substantial distances into Venice Lagoon. They gradually become strongly asymmetric with the rear of the depression becoming extremely steep, similar to a bore. As they are dynamically similar, air pressure fluctuations moving over variable-depth coastal areas could generate meteorological tsunamis with a leading depression wave followed by a devastating bore-like feature.

A Comprehensive Laboratory Study On The Immersion Freezing Behavior Of Illite Nx Particles: A Comparison Of 17 Ice Nucleation Measurement Techniques, N. Hiranuma, S. Augustin-Bauditz, H. Bingemer, C. Budke, J. Curtius, A. Danielczok, K. Diehl, K. Dreischmeier, M. Ebert, F. Frank, N. Hoffmann, K. Kandler, A. Kiselev, T. Koop, T. Leisner, O. Möhler, B. Nillius, A. Peckhaus, D. Rose, S. Weinbruch, H. Wex, Y. Boose, P. J. Demott, J. D. Hader, T. C.J. Hill, Z. A. Kanji, G. Kulkarni, E. J.T. Levin, C. S. Mccluskey, M. Murakami, B. J. Murray, D. Niedermeier

Michigan Tech Publications

Immersion freezing is the most relevant heterogeneous ice nucleation mechanism through which ice crystals are formed in mixed-phase clouds. In recent years, an increasing number of laboratory experiments utilizing a variety of instruments have examined immersion freezing activity of atmospherically relevant ice-nucleating particles. However, an intercomparison of these laboratory results is a difficult task because investigators have used different ice nucleation (IN) measurement methods to produce these results. A remaining challenge is to explore the sensitivity and accuracy of these techniques and to understand how the IN results are potentially influenced or biased by experimental parameters associated with these techniques. …

Green Synthesis, Photocatalytic And Photoelectrochemical Performance Of Au-Graphene Nanocomposite, Mohammad Mansoob Khan Dr, Mohammad Ehtisham Khan, M. H. Cho

Dr. Mohammad Mansoob Khan

A simplistic and environment friendly approach using electrochemically active biofilms (EABs) was developed for the synthesis of Au-Graphene (Au-G) nanocomposite without the use of surfactants or capping agents. The as-prepared Au-G nanocomposite was characterized by X-ray diffraction, diffuse reflectance spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, photoluminescence spectroscopy, and transmission electron microscopy. In this study, the anchoring of gold nanoparticles (AuNPs) on graphene sheets was achieved using an EAB. The EAB assists in the bio-reduction of Au3+ to Au0, and the AuNPs prevent the aggregation of graphene sheets and keep them apart because of the decrease in attractive forces between the …

The Fierce Green Fire: Vol 5 Issue 16, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.

Stellar Activity And Its Implications For Exoplanet Detection On Gj 176, Paul Robertson, Michael Endl, Gregory W. Henry, William D. Cochran, Phillip J. Macqueen, Michael H. Williamson

Information Systems and Engineering Management Research Publications

We present an in-depth analysis of stellar activity and its effects on radial velocity (RV) for the M2 dwarf GJ 176 based on spectra taken over 10 yr from the High Resolution Spectrograph on the Hobby–Eberly Telescope. These data are supplemented with spectra from previous observations with the HIRES and HARPS spectrographs, and V- and R-band photometry taken over six years at the Dyer and Fairborn observatories. Previous studies of GJ 176 revealed a super-Earth exoplanet in an 8.8-day orbit. However, the velocities of this star are also known to be contaminated by activity, particularly at the 39-day stellar rotation …

Spatial And Temporal Variability Of Rainfall In The Gandaki River Basin Of Nepal Himalaya, Jeeban Panthi, Piyush Dahal, Madan Lall Shrestha, Suman Aryal, Nir Y. Krakauer, Soni M. Pradhanang, Tarendra Lakhankar, Ajay K. Jha, Mohan Sharma, Ramchandra Karki

Publications and Research

Landslides, floods, and droughts are recurring natural disasters in Nepal related to too much or too little water. The summer monsoon contributes more than 80% of annual rainfall, and rainfall spatial and inter-annual variation is very high. The Gandaki River, one of the three major rivers of Nepal and one of the major tributaries of the Ganges River, covers all agro-ecological zones in the central part of Nepal. Time series tests were applied for different agro-ecological zones of the Gandaki River Basin (GRB) for rainfall trends of four seasons (pre-monsoon, monsoon, post-monsoon and winter) from 1981 to 2012. The non-parametric …

Dynamics Of Marine Bacterial Community Diversity Of The Coastal Waters Of The Reefs, Inlets, And Wastewater Outfalls Of Southeast Florida, Alexandra Mandina Campbell, Jay Fleisher, Christopher D. Sinigalliano, James R. White, Jose V. Lopez

Marine & Environmental Sciences Faculty Articles

Coastal waters adjacent to populated southeast Florida possess different habitats (reefs, oceanic inlets, sewage outfalls) that may affect the composition of their inherent microbiomes. To determine variation according to site, season, and depth, over the course of 1 year, we characterized the bacterioplankton communities within 38 nearshore seawater samples derived from the Florida Area Coastal Environment (FACE) water quality survey. Six distinct coastal locales were profiled – the Port Everglades and Hillsboro Inlets, Hollywood and Broward wastewater outfalls, and associated reef sites using culture-independent, high-throughput pyrosequencing of the 16S rRNA V4 region. More than 227,000 sequences helped describe longitudinal taxonomic …

Magnetic Response Of Aperiodic Wire Networks Based On Fibonacci Distortions Of Square Antidot Lattices, Barry Farmer, Vinayak Bhat, J. Sklenar, Eric Teipel, Justin Woods, J. B. Ketterson, J. Todd Hastings, Lance Delong

Physics and Astronomy Faculty Publications

The static and dynamic magnetic responses of patterned ferromagnetic thin films are uniquely altered in the case of aperiodic patterns that retain long-range order (e.g., quasicrystals). We have fabricated permalloy wire networks based on periodic square antidot lattices (ADLs) distorted according to an aperiodic Fibonacci sequence applied to two lattice translations, d₁  = 1618 nm and d₂  = 1000 nm. The wire segment thickness is fixed at t = 25 nm, and the width W varies from 80 to 510 nm. We measured the DC magnetization between room temperature and 5 K. Room-temperature, narrow-band (9.7 GHz) ferromagnetic resonance …

The Hosoya Entropy Of A Graph, Abbe Mowshowitz, Matthias Dehmer

Publications and Research

This paper demonstrates properties of Hosoya entropy, a quantitative measure of graph complexity based on a decomposition of the vertices linked to partial Hosoya polynomials. Connections between the information content of a graph and Hosoya entropy are established, and the special case of Hosoya entropy of trees is investigated.

Addressing Light Pollution At Utah State University, Rachel Nydegger

Browse All Undergraduate research

Many outdoor light fixtures illuminate in all directions, meaning that a large por- tion of light emitted is sent upwards. This excess of light light pollution – repre- sents wasted energy and money, decreases public safety, harms nocturnal and migra- tory animals, and destroys our view of the night sky. While Utah State University Facilities does have a program in place to retrofit light fixtures, and newly installed fixtures are chosen with light pollution in consideration, many of the light posts on campus continue to pollute the night sky. With the support of the Student Sustain- ability Offices Blue Goes …

Home Range Use And Movement Patterns Of Non-Native Feral Goats In A Tropical Island Montane Dry Landscape, Mark William Chynoweth, Christopher A. Lepczyk, Creighton M. Litton, Steven C. Hess, James R. Kellner, Susan Cordell

Wildland Resources Faculty Publications

Advances in wildlife telemetry and remote sensing technology facilitate studies of broad-scale movements of ungulates in relation to phenological shifts in vegetation. In tropical island dry landscapes, home range use and movements of non-native feral goats (Capra hircus) are largely unknown, yet this information is important to help guide the conservation and restoration of some of the world’s most critically endangered ecosystems. We hypothesized that feral goats would respond to resource pulses in vegetation by traveling to areas of recent green-up. To address this hypothesis, we fitted six male and seven female feral goats with Global Positioning System (GPS) collars …

Assessment Of Surface Soil Moisture Using High-Resolution Multi-Spectral Imagery And Artificial Neural Networks, Leila Hassan-Esfahani, Alfonso Torres-Rua, Austin Jensen, Mac Mckee

AggieAir Publications

Many crop production management decisions can be informed using data from high-resolution aerial images that provide information about crop health as influenced by soil fertility and moisture. Surface soil moisture is a key component of soil water balance, which addresses water and energy exchanges at the surface/atmosphere interface; however, high-resolution remotely sensed data is rarely used to acquire soil moisture values. In this study, an artificial neural network (ANN) model was developed to quantify the effectiveness of using spectral images to estimate surface soil moisture. The model produces acceptable estimations of surface soil moisture (root mean square error (RMSE) = …

Identifying Key Variables And Interactions In Statistical Models Of Building Energy Consumption Using Regularization, David Hsu

David Hsu

Statistical models can only be as good as the data put into them. Data about energy consumption continues to grow, particularly its non-technical aspects, but these variables are often interpreted differently among disciplines, datasets, and contexts. Selecting key variables and interactions is therefore an important step in achieving more accurate predictions, better interpretation, and identification of key subgroups for further analysis.

This paper therefore makes two main contributions to the modeling and analysis of energy consumption of buildings. First, it introduces regularization, also known as penalized regression, for principled selection of variables and interactions. Second, this approach is demonstrated by …

The Effects Of Variable Viscosity On The Peristaltic Flow Of Non-Newtonian Fluid Through A Porous Medium In An Inclined Channel With Slip Boundary Conditions, Ambreen Afsar Khan, R. Ellahi, Muhammad Usman

Muhammad Usman

The present paper investigates the peristaltic motion of an incompressible non-Newtonian fluid with variable viscosity through a porous medium in an inclined symmetric channel under the effect of the slip condition. A long wavelength approximation is used in mathematical modeling. The system of the governing nonlinear partial differential equation has been solved by using the regular perturbation method and the analytical solutions for velocity and pressure rise have been obtained in the form of stream function. In the obtained solution expressions, the long wavelength and low Reynolds number assumptions are utilized. The salient features of pumping and trapping phenomena are …