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Soil Organic Matter Dynamics In Bioenergy Cropping Systems, Jane Achando Khatenje

Student Theses and Dissertations

Ethanol and other advanced biofuels from cellulosic biomass, plant stalks, trunks, stems, and leaves are renewable alternatives expected to significantly produce improved or expanded renewable energy sources to meet the current energy demand. Therefore, we need to better understand the production of renewable energy sources needs. The long term combined effects of tillage, cropping systems and nutrient sources fertilization on active and slow fractions of soil organic matter dynamics need to be realized. The objectives of this research are to: 1) determine the effects of different nutrient sources on soil organic matter dynamics and 2) determine the effects of bioenergy …

Modeling Gross Primary Production Of Irrigated And Rain-Fed Maize Using Modis Imagery And Co2 Flux Tower Data, Joshua L. Kalfas, Xiangming Xiao, Diana X. Vanegas, Shashi B. Verma, Andrew E. Suyker

School of Natural Resources: Faculty Publications

Abstract

Information on gross primary production (GPP) of maize croplands is needed for assessing and monitoring maize crop conditions and the carbon cycle. A number of studies have used the eddy covariance technique to measure net ecosystem exchange (NEE) of CO₂ between maize cropland fields and the atmosphere and partitioned NEE data to estimate seasonal dynamics and interannual variation of GPP in maize fields having various crop rotation systems and different water management practices. How to scale up in situ observations from flux tower sites to regional and global scales is a challenging task. In this study, the Vegetation …

Meeting Reports: Research On Coupled Human And Natural Systems (Chans): Approach, Challenges, And Strategies, Marina Alberti, Heidi Asbjornsen, Lawrence A. Baker, Nicholas Brozovic, Laurie E. Drinkwater, Scott A. Drzyzga, Claire A. Jantz, José Fragoso, Daniel S. Holland, Timothy A. Kohler, Jianguo Liu, William J. Mcconnell, Herbert D.G. Maschner, James D.A. Millington, Michael Monticino, Guillermo Podestá, Robert Gilmore Pontius, Charles L. Redman, Nicholas J. Reo, David Sailor, Gerald Urquhart

Daugherty Water for Food Global Institute: Faculty Publications

Understanding the complexity of human–nature interactions is central to the quest for both human well-being and global sustainability. To build an understanding of these interactions, scientists, planners, resource managers, policymakers, and communities increasingly are collaborating across wide-ranging disciplines and knowledge domains. Scientists and others are generating new integrated knowledge on top of their requisite specialized knowledge to understand complex systems in order to solve pressing environmental and social problems (e.g., Carpenter et al. 2009). One approach to this sort of integration, bringing together detailed knowledge of various disciplines (e.g., social, economic, biological, and geophysical), has become known as the study …

Geochemistry Of Hydrothermal Fluids From The Pacmanus, Northeast Pual And Vienna Woods Hydrothermal Fields, Manus Basin, Papua New Guinea, Eoghan P. Reeves, Jeffrey S. Seewald, Peter Saccocia, Wolfgang Bach, Paul R. Craddock, Wayne C. Shanks Iii, Sean P. Sylva, Emily Walsh, Thomas Pichler, Martin Rosner

Geological Sciences Faculty Publications

Processes controlling the composition of seafloor hydrothermal fluids in silicic back-arc or near-arc crustal settings remain poorly constrained despite growing evidence for extensive magmatic–hydrothermal activity in such environments. We conducted a survey of vent fluid compositions from two contrasting sites in the Manus back-arc basin, Papua New Guinea, to examine the influence of variations in host rock composition and magmatic inputs (both a function of arc proximity) on hydrothermal fluid chemistry. Fluid samples were collected from felsic-hosted hydrothermal vent fields located on Pual Ridge (PACMANUS and Northeast (NE) Pual) near the active New Britain Arc and a basalt-hosted vent field …

Temperature Increase Effects On Sagebrush Ecosystem Forbs: Exprimental Evidence And Range Manager Perspectives, Hilary Louise Whitcomb

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.

Ordway Weather And Water Data 2011, Macalester College

Ordway Weather Data

Contains daily readings for the year indicated. The values include: PAR umol/s/m2, avg wind dir degree, avg windspeed mph, Avg Max Windspeed mph, Avg airtemp C, Avg RH %, Avg BP mmHg, Avg DailyRain in, Avg Rain Duration sec, Avg RainIntensity in/h, Avg Water Temp F, Avg sp cond mS/cm, avg pH, Avg Turb NTU+, Avg ODOSat %, Avg ODO mg/L, Water station PAR umol/s/m2, Avg Water Level m. File format: CSV.

A Guide To Fuels Management In Riparian Areas Of The Interior West, Final Report, Kathleen A. Dwire, Kristen E. Meyer, Sandra E. Ryan, Gregg Riegel, Timothy Burton

Joint Fire Science Program Synthesis Reports

Fuel treatments in riparian areas pose distinct challenges. Riparian areas are protected by administrative regulations, many of which are largely custodial and restrict active management. However, riparian areas have also been affected by fire suppression, land use, and disturbance and manipulative treatments of fuels may be needed to maintain riparian biodiversity and restore valued functions. This project is a synthesis of the current knowledge regarding fuels treatments in riparian areas of the interior western USA. It summarizes the most recent scientific literature, but also incorporates the practical knowledge gained by resource managers who have been utilizing different techniques to reduce …

Active Pharmaceutical Ingredients And Aquatic Organisms, Christian G. Daughton, Bryan W. Brooks

United States Environmental Protection Agency: Publications

The presence of active pharmaceuticals ingredients (APIs) in aquatic systems has led in recent years to a burgeoning literature examining environmental occurrence, fate, effects, risk assessment, and treatability of these compounds. The vast preponderance of studies aimed at identifying and quantifying contaminant residues in aquatic tissues have involved the conventional and legacy pollutants. Comparatively few studies have been targeted at APIs, primarily those that are lipophilic. Although APIs have received much attention as "emerging" contaminants of concern, it is important to recognize that traditional approaches to understand and predict exposure and effects of other environmental organic contaminant classes mayor may …

Dissolved Organic Matter Composition And Photoreactivity In Prairie Lakes Of The U.S. Great Plains, Christopher L. Osburn, Courtney R. Wigdahl, Sherilyn C. Fritz, Jasmine E. Saros

Department of Earth and Atmospheric Sciences: Faculty Publications

Dissolved organic matter (DOM) of 27 prairie saline lake ecosystems was investigated in the Northern and Central Great Plains of the United States using absorbance, fluorescence, lignin concentration, and stable C isotope values. The majority of variation in DOM fluorescence among lakes was due to humic (peak C) and microbially formed (peak M) fluorescent components, which appear to be derived from autochthonous primary production. Strong correlations between peak M and nutrients allow us to model total phosphorus (TP) concentration using peak M fluorescence and chromophoric dissolved organic matter (CDOM) absorption. The rate of primary production (PP) was positively correlated with …

Ecology And Biogeography Of The Piedmont Blue Burrower (Cambarus [Depressicambarus] Harti), Troy Keller

Faculty Bibliography

No abstract provided.

Profiles In Science For Science Librarians: "What Lives Where, And Why": Alfred Russel Wallace, And The Field Of Biogeography, Charles H. Smith

DLPS Faculty Publications

Biogeography, the study of animal and plant distribution, has a history extending back to at least the eighteenth century. But it was not until the work of Charles Darwin and Alfred Russel Wallace in the mid-nineteenth century that it really came into its own as a science. Darwin’s importance notwithstanding, it was really Wallace who put the field on the map, and many of today’s research threads can be traced back to his influence. This article provides a summary review of Wallace’s life and work and biogeography as a field of study, including Wallace’s role in its development.

Soil Carbon Distribution In Alaska In Relation To Soil-Forming Factors, Kristofer D. Johnson, Jennifer Harden, A. David Mcguire, Norman B. Bliss, James G. Bockheim, Mark Clark, Teresa Nettleton-Hollingsworth, M. Torre Jorgenson, Evan S. Kane, Michelle Mack, Jonathan O'Donnell, Chien-Lu Ping, Edward A.G. Schuur, Merritt R. Turetsky, David W. Valentine

United States Geological Survey: Staff Publications

The direction and magnitude of soil organic carbon (SOC) changes in response to climate change remain unclear and depend on the spatial distribution of SOC across landscapes. Uncertainties regarding the fate of SOC are greater in high-latitude systems where data are sparse and the soils are affected by sub-zero temperatures. To address these issues in Alaska, a first-order assessment of data gaps and spatial distributions of SOC was conducted from a recently compiled soil carbon database. Temperature and landform type were the dominant controls on SOC distribution for selected ecoregions. Mean SOC pools (to a depth of 1-m) varied by …

Subaerial Freshwater Stromatolites In Deer Cave, Sarawak – A Unique Geobiological Cave Formation, Joyce Lundberg, Donald A. Mcfarlane

WM Keck Science Faculty Papers

A suite of distinctive freshwater subaerial phosphatic stromatolites is developed close to the northeastern entrance of Deer Cave, Gunung Mulu National Park, Sarawak, Borneo, in conditions of very low light but ample supply of nutrients from guano. These stromatolites are not particulate; they are composed of alternating layers of more porous and more dense amorphous hydroxylapatite. This biomineralization occurs as moulds of coccoid (the majority) and filamentous (less abundant) cyanobacteria. Mineralization occurs at a pH of ~ 7.0 in the extracellular sheaths and in micro-domains of varying carbonate content in the surrounding mucus of the biofilm. The most recent surfaces …

Farmer Perceptions Of Sustainable Agriculture Practices And Drought Risk Reduction In Nebraska, Usa, Cody L. Knutson, Tonya Haigh, Michael J. Hayes, Melissa Widhalm, J. Nothwehr, M. Kleinschmidt, L. Graf

National Drought Mitigation Center: Faculty Publications

Social factors, such as farming methods, have an impact on farm vulnerability to drought, but have received little research or policy attention. Some researchers and advocates have argued that sustainable agriculture systems are less vulnerable to climate risk than conventional systems because sustainable agriculture requires producers to have skills promoting adaptability. In this paper, we investigate producers’ perceptions on the use of sustainable agriculture in reducing drought risk, and what they believe would help them better adapt to drought. We surveyed and interviewed farmer members of two sustainable agriculture organizations in Nebraska, USA, during a multi-year drought period from 1999 …

Stable Isotopic Constraints Of The Turpan Basin In Northwestern China, Allen J. Schaen

Undergraduate Review

Stable isotopic analysis of sedimentary rocks can be used to reconstruct past geologic changes in the elevation and climate of topographic features such as mountain ranges and plateaus. The Tibetan Plateau is an ideal field laboratory for conducting this type of study because of the Plateau’s extreme topographic relief and relatively recent geologic growth. Here we present oxygen and carbon isotope compositions from a suite of sedimentary rock samples taken from the western Turpan Basin in northwestern China. This area of the basin collects sediment from weathering and erosion of the Bogda Shan located to the north. The goal of …

State Of The Climate In 2010, Jessica Blunden, Derek S. Arndt, Molly O. Baringer

United States Department of Commerce: Staff Publications

Several large-scale climate patterns influenced climate conditions and weather patterns across the globe during 2010. The transition from a warm El Niño phase at the beginning of the year to a cool La Niña phase by July contributed to many notable events, ranging from record wetness across much of Australia to historically low Eastern Pacific basin and near-record high North Atlantic basin hurricane activity. The remaining five main hurricane basins experienced below- to well-below-normal tropical cyclone activity. The negative phase of the Arctic Oscillation was a major driver of Northern Hemisphere temperature patterns during 2009/10 winter and again in late …

Partially Acetylated Sugarcane Bagasse For Wicking Oil From Contaminated Wetlands, Seungoon Chung, Makram T. Suidan, Albert D. Venosa

United States Environmental Protection Agency: Publications

Sugarcane bagasse was partially acetylated to enhance its oil-wicking ability in saturated environments while holding moisture for hydrocarbon biodegradation. The water sorption capacity of raw bagasse was reduced fourfold after treatment, which indicated considerably increased hydrophobicity but not a limited capability to hold moisture for hydrocarbon biodegradation. Characterization results by Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), X-ray diffraction (XRD), and surface area analyzer suggested that treated bagasse exhibited enhanced hydrophobicity and surface area. Oil wicking test results indicate that treated bagasse is more effective in wicking oil from highly saturated environments than raw bagasse and suggest that application …

Time-Lapse Three-Dimensional Inversion Of Complex Conductivity Data Using An Active Time Constrained (Atc) Approach, M. Karaoulis, A. Revil, D. D. Werkema, B. J. Minsley, W. F. Woodruff, A. Kemna

United States Environmental Protection Agency: Publications

Induced polarization (more precisely the magnitude and phase of impedance of the subsurface) is measured using a network of electrodes located at the ground surface or in boreholes. This method yields important information related to the distribution of permeability and contaminants in the shallow subsurface. We propose a new time-lapse 3-D modelling and inversion algorithm to image the evolution of complex conductivity over time.We discretize the subsurface using hexahedron cells. Each cell is assigned a complex resistivity or conductivity value. Using the finite-element approach, we model the in-phase and out-of-phase (quadrature) electrical potentials on the 3-D grid, which are then …

Estimating Age From Recapture Data: Integrating Incremental Growth Measures With Ancillary Data To Infer Age-At-Length, Mitchell J. Eaton, William A. Link

United States Geological Survey: Staff Publications

Estimating the age of individuals in wild populations can be of fundamental importance for answering ecological questions, modeling population demographics, and managing exploited or threatened species. Significant effort has been devoted to determining age through the use of growth annuli, secondary physical characteristics related to age, and growth models. Many species, however, either do not exhibit physical characteristics useful for independent age validation or are too rare to justify sacrificing a large number of individuals to establish the relationship between size and age. Length-at-age models are well represented in the fisheries and other wildlife management literature. Many of these models …

Demographic Responses Of Least Terns And Piping Plovers To The 2011 Missouri River Flood—A Large-Scale Case Study, Michael J. Anteau, Mark H. Sherfy, Terry L. Shaffer, Rose J. Swift, Dustin L. Toy, Colin M. Dovichin

United States Geological Survey: Publications

2011 led to substantial changes in abundance and distribution of unvegetated sand habitat. This river system is a major component of the breeding range for interior Least terns (Sternula antillarum; “terns”) and piping plovers (Charadrius melodus; “plovers”), both of which are Federally listed ground-nesting birds that prefer open, unvegetated sand and gravel nesting substrates on sandbars and shorelines. The 2011 flood inundated essentially all tern and plover nesting habitat during 2011, but it had potential to generate post-flood habitat conditions that favored use by terns and plovers in subsequent years. We compared several tern and plover demographic parameters during the …

The Role Of Demographic Compensation Theory In Incidental Take Assessments For Endangered Species, Conor P. Mcgowan, Mark R. Ryan, Michael C. Runge, Joshua J. Millspaugh, Jean Fitts Cochrane

United States Geological Survey: Staff Publications

Many endangered species laws provide exceptions to legislated prohibitions through incidental take provisions as long as take is the result of unintended consequences of an otherwise legal activity. These allowances presumably invoke the theory of demographic compensation, commonly applied to harvested species, by allowing limited harm as long as the probability of the species’ survival or recovery is not reduced appreciably. Demographic compensation requires some density-dependent limits on survival or reproduction in a species’ annual cycle that can be alleviated through incidental take. Using a population model for piping plovers in the Great Plains, we found that when the population …

Selenium In Birds, Harry M. Ohlendorf, Gary H. Heinz

United States Geological Survey: Staff Publications

Selenium (Se) is a metalloid trace element that birds and other wildlife need in small amounts for good health. The main purpose of this chapter is to interpret tissue concentrations of Se. However, because food is the main source of Se accumulation for birds and other wildlife, and because dietary concentrations for effects on bird reproduction have been reported, we also provide interpretive information on Se in the diet.

Se deficiencies in domestic poultry and livestock occur in some parts of the world and must be corrected by additions of Se to the diet. However, the range of dietary concentrations …

History Of Wildlife Toxicology And The Interpretation Of Contaminant Concentrations In Tissues, Barnett A. Rattner, Anton M. Scheuhammer, John E. Ellott

United States Geological Survey: Staff Publications

The detection and interpretation of contaminants in tissues of wildlife belongs to the field of toxicology, a scientific discipline with a long, intriguing, and illustrious history (reviewed by Hayes 1991, Gallo 2001, Gilbert and Hayes 2006, Wax 2006). We review its history briefly, to provide a context for understanding the use of tissue residues in toxicology, and to explain how their use has developed over time. Because so much work has been conducted on mercury, and dioxins and polychlorinated biphenyls (PCBs), separate case histories are included that describe the evolution of the use of tissue concentrations to assess exposure and …

Droughtscape, Winter 2011, Kelly Smith

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Register for the U.S. Drought Monitor Forum

La Niña Brings Southeast, Southwest Drought

International Efforts

Drought Returns in 2010

Impacts Emerge “Before” Summer Drought in East

October-December Quarterly Impacts Summary

Climate Adaptation for Local Government

NDMC Elicits Missouri River Basin Recollections

Woudenberg Coordinates Educational Booklet

Predicting The Ancient Occurrence Of Evaporites Using Paleoclimate Modelling, Amiratu Yamusah

Earth & Environmental Sciences Theses - Archive

Evaporites are climatic indicators that depend on two main variables: mean annual temperature and mean annual precipitation. This study constructs a model that predicts the localities of ancient evaporites based on paleo- temperature and paleo- precipitation data. A climate envelope, a bivariate plot of temperature and precipitation, is constructed by intersecting the modern temperature and precipitation with climate data obtained from Fast Ocean Atmosphere Model (FOAM). Modern evaporites have a limited extent hence in this research, the yermosols- solonchak soil type was used as a proxy. The predictions were made for 16 time intervals. These were plotted on paleogeographic reconstructions …

Tapeworms Of Elasmobranchs, Part Iii: A Monograph On The Phyllobothriidae (Platyhelminthes, Cestoda), Timothy R. Ruhnke

Bulletin of the University of Nebraska State Museum (1924–2023)

This monograph aims to provide information on the taxonomic status of all genera associated with the tetraphyllidean family Phyllobothriidae. Full treatments of the three valid species of the type genus, Phyllobothrium, in addition to the 47 valid species of Clistobothrium, Crossobothrium, Marsupiobothrium, Monorygma, Nandocestus, Orectolobicestus, Orygmatobothrium, Paraorygmatobothrium, Ruhnkecestus, and Scyphophyllidium are provided, as is a taxonomic history of the family. Of the valid genera historically associated with the family, only Phyllobothrium is considered to be an unambiguous member of the family. The genera Bibursibothrium, Calyptrobothrium, Cardiobothrium, Clistobothrium, Crossobothrium, Doliobothrium, Flexibothrium, Marsupiobothrium, Monorygma, Nandocestus, Orectolobicestus, Orygmatobothrium, Paraorygmatobothrium, Ruhnkecestus, Scyphophyllidium …

Communications And 'Forestructures' At The Geological Intersection Of Caves And Subsurface Water Flow: Hermeneutics And Parochialism, Lee J. Florea, H. L. Vacher

Geology Faculty Publications

The direction of cave and karst science throughout its history has been partly determined by communication—or, more commonly, the lack of communication—between non-scientist cavers and non-caving physical geologists writing about karst. Within each community, advancement of ‘cave awareness’ occurred through a hermeneutic circle in which ‘forestructures’ guided progress. One result was regionalism of speleo-genetic theories developed within karst science because of the weight of evidence placed upon local or regional observations. Many speleogenetic theories of the mid-1900s suffer from this parochialism, failing to take into account findings from karst of different geologic settings. During the past half-century, the accumulated worldwide …

Landscapes And Soils Of The Lake Grace District, D N. Sawkins

Bulletins 4000 -

The publication aims to provide readers with the principles underlying the formation of local landscapes and soils, and the ability to identify landscapes and their associated soils.

Variations In Concentrations And Compositions Of Polycyclic Aromatic Hydrocarbons (Pahs) In Coals Related To The Coal Rank And Origin, Susanne Laumann, Vesna Micic Batka, Michael A. Kruge, Christine Achten, Reinhard Sachsenhofer, Jan Schwarzbauer, Thilo Hofmann

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The release of unburnt coal particles and associated polycyclic aromatic hydrocarbons (PAHs) may cause adverse impacts on the environment. This study assessed variations in the concentration and composition of PAHs in a set of fifty coal samples from eleven coal basins worldwide. The maximum PAH concentrations at high volatile bituminous rank were recorded in samples from a single basin. Considering the entire sample, the highest PAH concentrations were in fact found outside of this rank range, suggesting that the maceral composition and thus the coal's origin also influenced PAH concentrations. The examination of the PAH compositions revealed that alkylated 2-3 …

Proceedings Of The 2011 International Conference On Karst Hydrogeology And Ecosystems, Jason Samuel Polk, Leslie A. North

Environmental Sustainability Books

Jointly sponsored by the Hoffman Environmental Research Institute, the National Cave & Karst Research Institute, and the International Association of Hydrogeologists, the 2011 International Conference on Karst Hydrogeology and Ecosystems was held at Western Kentucky University in Bowling Green, Kentucy on 8-10 June 2011. Topics include karst geomorphology, engineering and modeling, isotope geochemistry, and cultural and educational aspects of karst environments.