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An Appraisal Of Experiences Of Climate Change And Adaptive Response To Heat Stress By Farmers In Rural Ghana, Kwasi Frimpong Jan 2015

An Appraisal Of Experiences Of Climate Change And Adaptive Response To Heat Stress By Farmers In Rural Ghana, Kwasi Frimpong

Theses: Doctorates and Masters

With the increase in average global temperatures, heat-related illnesses and deaths have unfolded as occupational and health issues. Periods of high to extreme temperatures are becoming more common and are a leading cause of weather-related deaths in many countries. In agricultural settings of African countries, heat stress is a major concern as many smallholder farmers work outdoors with limited access to cooling systems even in their resting and living environments. This study, conducted in the Bawku East part of Northern-East Ghana in 2013, examines, in the context of climate change, the trends and impacts of heat stress on smallholder farmers, …


Boundaries Of Governance: Social Responsibility In Mining In Western Australia, Gemma L. Broderick Jan 2015

Boundaries Of Governance: Social Responsibility In Mining In Western Australia, Gemma L. Broderick

Theses: Doctorates and Masters

This research investigated the boundaries of governance of social responsibility in three multinational mining organisations based in Perth, Western Australia. The mining industry has economic, environmental and social impacts, both positive and negative. While most of the attention of the media and supporters in government seems to focus on the positive impacts, a growing concern regarding the social implications of mining is clearly evident in public discourse and the academic literature. In response to public concern, the mining industry has adopted terms such as ‘sustainability’, ‘sustainable development’, ‘social licence to operate’ and ‘social responsibility’. Such phrases are widely used in …


Strengthening Confidence In Climate Change Impact Science, Mary I. O'Connor, Johnna M. Holding, Carrie V. Kappel, Carlos M. Duarte, Keith Brander, Christopher J. Brown, John F. Bruno, Lauren Buckley, Michael T. Burrows, Benjamin S. Halpern, Wolfgang Kiessling, Pippa Moore, John M. Pandolfi, Camille Parmesan, Elvira S. Poloczanska, David S. Schoeman, William J. Sydeman, Anthony J. Richardson Jan 2015

Strengthening Confidence In Climate Change Impact Science, Mary I. O'Connor, Johnna M. Holding, Carrie V. Kappel, Carlos M. Duarte, Keith Brander, Christopher J. Brown, John F. Bruno, Lauren Buckley, Michael T. Burrows, Benjamin S. Halpern, Wolfgang Kiessling, Pippa Moore, John M. Pandolfi, Camille Parmesan, Elvira S. Poloczanska, David S. Schoeman, William J. Sydeman, Anthony J. Richardson

Research outputs 2014 to 2021

Aim: To assess confidence in conclusions about climate-driven biological change through time, and identify approaches for strengthening confidence scientific conclusions about ecological impacts of climate change. Location: Global. Methods: We outlined a framework for strengthening confidence in inferences drawn from biological climate impact studies through the systematic integration of prior expectations, long-term data and quantitative statistical procedures. We then developed a numerical confidence index (Cindex) and used it to evaluate current practices in 208 studies of marine climate impacts comprising 1735 biological time series. Results: Confidence scores for inferred climate impacts varied widely from 1 to 16 (very low to …


Above- And Belowground Biomass And Soil Respiration In A Low-Input Perennial Biofuel Production System, Jordan Young, Jessica Abernathy, Kenneth Elgersma Jan 2015

Above- And Belowground Biomass And Soil Respiration In A Low-Input Perennial Biofuel Production System, Jordan Young, Jessica Abernathy, Kenneth Elgersma

Undergraduate Student Work

Backgroud

  • Global climate change largely depends on the atmospheric carbon balance, of which soil respiration is a significant component.
  • Native perennial prairie vegetation is being tested as an alternative to corn for renewable biofuel production.
  • Mixtures of this vegetation are considered ‘carbon negative’ because net CO2 sequestration exceeds atmospheric release1.
  • Studies have shown that aboveground biomass and the rate of carbon sequestration are both increased by planting a diverse mixture of species versus a monoculture1.

Research Question:

How does the diversity of biofuel vegetation mixtures affect soil respiration, aboveground biomass and belowground biomass?


Land Use/Land Cover Changes And Regional Climate Over The Loess Plateau During 2001-2009 – Part Ii., Rezaul Mahmood Jan 2015

Land Use/Land Cover Changes And Regional Climate Over The Loess Plateau During 2001-2009 – Part Ii., Rezaul Mahmood

School of Natural Resources: Faculty Publications

No abstract provided.


Do Water Buffalo Facilitate Dispersal Of Invasive Alien Tree Species Acacia Nilotica In Bekol Savanna Baluran National Park?, Sutomo Jan 2015

Do Water Buffalo Facilitate Dispersal Of Invasive Alien Tree Species Acacia Nilotica In Bekol Savanna Baluran National Park?, Sutomo

Research outputs 2014 to 2021

Invasion of Acacia nilotica in Baluran National Park, East Java Province, Indonesia, has caused significant loss to savanna cover which is the main natural feature of the park. This study aimed to describe whether water buffalo may play a role in the dispersal of Acacia nilotica seed in Bekol Savanna usinganalysis of buffalo stools/scats, observations and seed experiments. In total there were 30 plots set up around the Bekol Savanna to collect buffalo stools. In addition,A. nilotica pods matured from its trees were collected, as controls. Germination tests were conducted on seeds that were extracted from the collected stools …


Effects Of Ambient Coarse, Fine, And Ultrafine Particles And Their Biological Constituents On Systemic Biomarkers: A Controlled Human Exposure Study, Ling Liu, Bruce Urch, Raymond Poon, Mieczyslaw Szyszkowicz, Mary Speck, Diane R. Gold, Amanda J. Wheeler, James A. Scott, Jeffrey R. Brook, Peter S. Thorne, Frances S. Silverman Jan 2015

Effects Of Ambient Coarse, Fine, And Ultrafine Particles And Their Biological Constituents On Systemic Biomarkers: A Controlled Human Exposure Study, Ling Liu, Bruce Urch, Raymond Poon, Mieczyslaw Szyszkowicz, Mary Speck, Diane R. Gold, Amanda J. Wheeler, James A. Scott, Jeffrey R. Brook, Peter S. Thorne, Frances S. Silverman

Research outputs 2014 to 2021

Background: Ambient coarse, fine, and ultrafine particles have been associated with mortality and morbidity. Few studies have compared how various particle size fractions affect systemic biomarkers. Objectives: We examined changes of blood and urinary biomarkers following exposures to three particle sizes. Methods: Fifty healthy nonsmoking volunteers, mean age of 28 years, were exposed to coarse (2.5–10 μm; mean, 213 μg/m3) and fine (0.15–2.5 μm; mean, 238 μg/m3) concentrated ambient particles (CAPs), and filtered ambient and/or medical air. Twenty-five participants were exposed to ultrafine CAP (< 0.3 μm; mean, 136 μg/m3) and filtered medical air. Exposures lasted 130 min, separated by ≥ 2 weeks. Blood/urine samples were collected preexposure and 1 hr and 21 hr postexposure to determine blood interleukin-6 and C-reactive protein (inflammation), endothelin-1 and vascular endothelial growth factor (VEGF; vascular mediators), and malondialdehyde (lipid peroxidation); as well as urinary VEGF, 8-hydroxy-deoxy-guanosine (DNA oxidation), and malondialdehyde. Mixed-model regressions assessed pre- and postexposure differences. results: One hour postexposure, for every 100-μg/m3 increase, coarse CAP was associated with increased blood VEGF (2.41 pg/mL; 95% CI: 0.41, 4.40) in models adjusted for O3, fine CAP with increased urinary malondialdehyde in single- (0.31 nmol/mg creatinine; 95% CI: 0.02, 0.60) and two-pollutant models, and ultrafine CAP with increased urinary 8-hydroxydeoxyguanosine in single- (0.69 ng/mg creatinine; 95% CI: 0.09, 1.29) and two-pollutant models, lasting < 21 hr. Endotoxin was significantly associated with biomarker changes similar to those found with CAPs. conclusions: Ambient particles with various sizes/constituents may influence systemic biomarkers differently. Endotoxin in ambient particles may contribute to vascular mediator changes and oxidative stress.


Analytical Pyrolysis Principles And Applications To Environmental Science, Michael A. Kruge Jan 2015

Analytical Pyrolysis Principles And Applications To Environmental Science, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Over the past half century, analytical pyrolysis has proven itself to be an effective means for the semiquantitative characterization of complex macromolecular organic substances. It has been demonstrated that instruments such as Py-FID, Py-MS, and in particular, Py-GC/MS can provide valuable geochemical insights when applied to a wide variety of problems in environmental science. The more widespread use of analytical pyrolysis methods in the evaluation of environmental pollution is recommended, because of their relatively low cost and information-rich results.

Pyrolysis is the heating of organic substances in an inert, oxygen-free atmosphere, thereby avoiding combustion. When performed on a large scale, …


Resource Nexus: Water, Energy, Food: Water Forum And Technology Roadmap, Rabi Mohtar, Rudolph A. Rosen Jan 2015

Resource Nexus: Water, Energy, Food: Water Forum And Technology Roadmap, Rabi Mohtar, Rudolph A. Rosen

Water Resources Science and Technology Book and E-Book Publications and Reports (Archived)

The Texas A&M University System and Area 41 co-hosted with Texas A&M University-San Antonio the Resource Nexus: Water Forum. Centering on the WEF Nexus Initiative of Texas A&M University, the two-day event held November 17-18, 2015, in San Antonio, Texas, focused on expanding the scope of the Water, Energy, Food (WEF) Nexus dialogue. Topics included identifying and responding to local, state, national and global challenges and opportunities relative to water resources in research, education, outreach and policy implementation. Other topics included holistic solutions to water security in Texas, and engaging stakeholders at home and worldwide in dialogues that will lead …


Participatory Conservation Of Coastal Habitats: The Importance Of Understanding Homeowner Decision Making To Mitigate Cascading Shoreline Degradation, Steven B. Scyphers, Steven J. Picou, Sean P. Powers Jan 2015

Participatory Conservation Of Coastal Habitats: The Importance Of Understanding Homeowner Decision Making To Mitigate Cascading Shoreline Degradation, Steven B. Scyphers, Steven J. Picou, Sean P. Powers

University Faculty and Staff Publications

Along densely populated coasts, the armoring of shorelines is a prevalent cause of natural habitat loss and degradation. This article explores the values and decision making of waterfront homeowners and identifies two interlinked and potentially reversible drivers of coastal degradation. We discovered that: (1) misperceptions regarding the environmental impacts and cost-effectiveness of different shoreline conditions was common and may promote armoring; and (2) many homeowners reported only altering their shorelines in response to damage caused by armoring on neighboring properties. Collectively, these findings suggest that a single homeowner’s decision may trigger cascading degradation along a shoreline, which highlights the necessity …


The Role Of Citizens In Detecting And Responding To A Rapid Marine Invasion, Steven B. Scyphers, Sean P. Powers, J. Lad Akins, J. Marcus Drymon, Charles W. Martin, Zeb H. Schobernd, Pamela J. Schofield, Robert L. Shipp, Theodore S. Switzer Jan 2015

The Role Of Citizens In Detecting And Responding To A Rapid Marine Invasion, Steven B. Scyphers, Sean P. Powers, J. Lad Akins, J. Marcus Drymon, Charles W. Martin, Zeb H. Schobernd, Pamela J. Schofield, Robert L. Shipp, Theodore S. Switzer

University Faculty and Staff Publications

Documenting and responding to species invasions requires innovative strategies that account for ecological and societal complexities. We used the recent expansion of Indo-Pacific lionfish (Pterois volitans/miles) throughout northern Gulf of Mexico coastal waters to evaluate the role of stakeholders in documenting and responding to a rapid marine invasion. We coupled an online survey of spearfishers and citizen science monitoring programs with traditional fishery-independent data sources and found that citizen observations documented lionfish 1–2 years earlier and more frequently than traditional reef fish monitoring programs. Citizen observations first documented lionfish in 2010 followed by rapid expansion and proliferation in …


Evaluating The Long-Term Effects Of Logging Residue Removals In Great Lakes Aspen Forests, Michael I. Premer Jan 2015

Evaluating The Long-Term Effects Of Logging Residue Removals In Great Lakes Aspen Forests, Michael I. Premer

Dissertations, Master's Theses and Master's Reports

Commercial aspen (Populus spp.) forests of the Great Lakes region are primarily managed for timber products such as pulp fiber and panel board, but logging residues (topwood and non-merchantable bolewood) are potentially important for utilization in the bioenergy market. In some regions, pulp and paper mills already utilize residues as fuel in combustion for heat and electricity, and progressive energy policies will likely cause an increase in biomass feedstock demand. The effects of removing residues, which have a comparatively high concentration of macronutrients, is poorly understood when evaluating long-term site productivity, future timber yields, plant diversity, stand dynamics, and …


On Underestimation Of Global Vulnerability To Tree Mortality And Forest Die-Off From Hotter Drought In The Anthropocene, Craig D. Allen, David D. Breshears, Nate G. Mcdowell Jan 2015

On Underestimation Of Global Vulnerability To Tree Mortality And Forest Die-Off From Hotter Drought In The Anthropocene, Craig D. Allen, David D. Breshears, Nate G. Mcdowell

United States Geological Survey: Staff Publications

Patterns, mechanisms, projections, and consequences of tree mortality and associated broadscale forest die-off due to drought accompanied by warmer temperatures—‘‘hotter drought’’, an emerging characteristic of the Anthropocene—are the focus of rapidly expanding literature. Despite recent observational, experimental, and modeling studies suggesting increased vulnerability of trees to hotter drought and associated pests and pathogens, substantial debate remains among research, management and policy-making communities regarding future tree mortality risks. We summarize key mortalityrelevant findings, differentiating between those implying lesser versus greater levels of vulnerability. Evidence suggesting lesser vulnerability includes forest benefits of elevated [CO2] and increased water-use efficiency; observed and modeled increases …


At-Grade Stabilization Structure Impact On Surface Water Quality Of An Agricultural Watershed, Kyle R. Minks, Matthew D. Ruark, Birl Lowery, Fred W. Madison, Dennis Frame, Todd D. Stuntebeck, Matthew J. Komiskey, George J. Kraft Jan 2015

At-Grade Stabilization Structure Impact On Surface Water Quality Of An Agricultural Watershed, Kyle R. Minks, Matthew D. Ruark, Birl Lowery, Fred W. Madison, Dennis Frame, Todd D. Stuntebeck, Matthew J. Komiskey, George J. Kraft

United States Geological Survey: Staff Publications

Decades of farming and fertilization of farm land in the unglaciated/Driftless Area (DA) of southwestern Wisconsin have resulted in the build-up of P and to some extent, N, in soils. This build-up, combined with steep topography and upper and lower elevation farming (tiered farming), exacerbates problems associated with runoff and nutrient transport in these landscapes. Use of an at-grade stabilization structure (AGSS) as an additional conservation practice to contour strip cropping and no-tillage, proved to be successful in reducing organic and sediment bound N and P within an agricultural watershed located in the DA. The research site was designed as …


Toxicity Reference Values For Chlorophacinone And Their Application For Assessing Anticoagulant Rodenticide Risk To Raptors, Barnett A. Rattner, Katherine E. Horak, Rebecca S. Lazarus, Sandra L. Schultz, Susan Knowles, Benjamin G. Abbo, Steven F. Volker Jan 2015

Toxicity Reference Values For Chlorophacinone And Their Application For Assessing Anticoagulant Rodenticide Risk To Raptors, Barnett A. Rattner, Katherine E. Horak, Rebecca S. Lazarus, Sandra L. Schultz, Susan Knowles, Benjamin G. Abbo, Steven F. Volker

United States Geological Survey: Staff Publications

Despite widespread use and benefit, there are

growing concerns regarding hazards of second-generation

anticoagulant rodenticides to non-target wildlife which

may result in expanded use of first-generation compounds,

including chlorophacinone (CPN). The toxicity of CPN

over a 7-day exposure period was investigated in American

kestrels (Falco sparverius) fed either rat tissue mechanically-

amended with CPN, tissue from rats fed Rozol bait

(biologically-incorporated CPN), or control diets (tissue

from untreated rats or commercial bird of prey diet)

ad libitum. Nominal CPN concentrations in the formulated

diets were 0.15, 0.75 and 1.5 µg/g food wet weight, and

measured concentrations averaged 94 …


Decadal Re-Evaluation Of Contaminant Exposure And Productivity Of Ospreys (Pandion Haliaetus) Nesting In Chesapeake Bay Regions Of Concern, Rebecca S. Lazarus, Barnett A. Rattner, Peter C. Mcgowan, Robert C. Hale, Sandra L. Schultz, Natalie K. Karouna-Renier, Mary Ann Ottinger Jan 2015

Decadal Re-Evaluation Of Contaminant Exposure And Productivity Of Ospreys (Pandion Haliaetus) Nesting In Chesapeake Bay Regions Of Concern, Rebecca S. Lazarus, Barnett A. Rattner, Peter C. Mcgowan, Robert C. Hale, Sandra L. Schultz, Natalie K. Karouna-Renier, Mary Ann Ottinger

United States Geological Survey: Staff Publications

The last large-scale ecotoxicological study of ospreys (Pandion haliaetus) in Chesapeake Bay was conducted in 2000-2001 and focused on U.S. EPA-designated Regions of Concern (ROCs; Baltimore Harbor/ Patapsco, Anacostia/middle Potomac, and Elizabeth Rivers). In 2011-2012, ROCs were re-evaluated to determine spatial and temporal trends in productivity and contaminants. Concentrations of p,p'-DDE were low in eggs and below the threshold associated with eggshell thinning. Eggs from the Anacostia/ middle Potomac Rivers had lower total PCB concentrations in 2011 than in 2000; however, concentrations remained unchanged in Baltimore Harbor. Polybrominated diphenyl ether flame retardants declined by 40%, and five alternative …


Interactive Effects Of Climate Change With Nutrients, Mercury, And Freshwater Acidification On Key Taxa In The North Atlantic Landscape Conservation Cooperative Region, Alfred E. Pinkney, Charles T. Driscoll, David C. Evers, Michael J. Hooper, Jeffrey Horan, Jess W. Jones, Rebecca S. Lazarus, Harold G. Marshall, Andrew Milliken, Barnett A. Rattner, John Schmerfeld, Donald W. Sparling Jan 2015

Interactive Effects Of Climate Change With Nutrients, Mercury, And Freshwater Acidification On Key Taxa In The North Atlantic Landscape Conservation Cooperative Region, Alfred E. Pinkney, Charles T. Driscoll, David C. Evers, Michael J. Hooper, Jeffrey Horan, Jess W. Jones, Rebecca S. Lazarus, Harold G. Marshall, Andrew Milliken, Barnett A. Rattner, John Schmerfeld, Donald W. Sparling

United States Geological Survey: Staff Publications

The North Atlantic Landscape Conservation Cooperative LCC (NA LCC) is a public–private partnership that provides information to support conservation decisions that may be affected by global climate change (GCC) and other threats. The NA LCC region extends from southeast Virginia to the Canadian Maritime Provinces. Within this region, the US National Climate Assessment documented increases in air temperature, total precipitation, frequency of heavy precipitation events, and rising sea level, and predicted more drastic changes. Here, we synthesize literature on the effects of GCC interacting with selected contaminant, nutrient, and environmental processes to adversely affect natural resources within this region. Using …


Global Change And Conservation Triage On National Wildlife Refuges, Fred Johnson, Mitchell J. Eaton, Gerard Mcmahon, Raye Nilius, Michael R. Bryant, Dave Case, Julien Martin, Nathan Wood, Laura Taylor Jan 2015

Global Change And Conservation Triage On National Wildlife Refuges, Fred Johnson, Mitchell J. Eaton, Gerard Mcmahon, Raye Nilius, Michael R. Bryant, Dave Case, Julien Martin, Nathan Wood, Laura Taylor

United States Geological Survey: Staff Publications

National Wildlife Refuges (NWRs) in the United States play an important role in the adaptation of social-ecological systems to climate change, land-use change, and other global-change processes. Coastal refuges are already experiencing threats from sea-level rise and other change processes that are largely beyond their ability to influence, while at the same time facing tighter budgets and reduced staff. We engaged in workshops with NWR managers along the U.S. Atlantic coast to understand the problems they face from global-change processes and began a multidisciplinary collaboration to use decision science to help address them. We are applying a values-focused approach to …


A Bird’S- Eye View Of The Usa National Phenology Network: An Off-The-Shelf Monitoring Program, Jherime Kellerman, Caroline A. F. Enquist, Diana L. Humple, Nathaniel E. Seavy, Alyssa Rosemartin, Renée L. Cormier, Lorianne Barnett Jan 2015

A Bird’S- Eye View Of The Usa National Phenology Network: An Off-The-Shelf Monitoring Program, Jherime Kellerman, Caroline A. F. Enquist, Diana L. Humple, Nathaniel E. Seavy, Alyssa Rosemartin, Renée L. Cormier, Lorianne Barnett

United States Geological Survey: Staff Publications

Phenology is central to the biology and ecology of organisms and highly sensitive to climate. Differential responses to climate change are impacting phenological synchrony of inter- acting species, which has been implicated in the decline of migratory birds that rely on seasonal resources. However, few studies explicitly measure phenology of seasonal habitat resources on the breeding and wintering grounds and at stopover sites. While avian monitoring methods are widely standardized, methods of monitoring resource phenology can be highly variable and difficult to integrate. The USA National Phenology Network (USA- NPN) has developed standardized plant and animal phenology protocols and a …


Is Shallow Water A Suitable Surrogate For Assessing Efforts To Address Pallid Sturgeon Population Declines?, T R. Gemeinhardt, N.J C. Gosch, D M. Morris, M L. Miller, T L. Welker, J L. Bonneau Jan 2015

Is Shallow Water A Suitable Surrogate For Assessing Efforts To Address Pallid Sturgeon Population Declines?, T R. Gemeinhardt, N.J C. Gosch, D M. Morris, M L. Miller, T L. Welker, J L. Bonneau

United States Army Corps of Engineers, Omaha District

It is hypothesized that slow, shallow water habitats benefit larval pallid sturgeon Scaphirhynchus albus; however, testing this hypothesis is difficult, given the low number of larval pallid sturgeon present in large rivers. In contrast, relatively large numbers of age-0 shovelnose sturgeon Scaphirhynchus platorynchus have been sampled, providing a potentially useful baseline to assess the importance of slow, shallow water to age-0 sturgeon of both species (hereafter age-0 sturgeon) in the lower Missouri River. Thus, we investigated the potential relationships between the prevalence of shallow water <1.5m and the age-0 sturgeon catch rates at multiple scales. Age-0 sturgeon were usually sampled in water >1.5 m, and catch rates were usually highest in the upper half [i.e. river kilometer …


Monthly Land Cover-Specific Evapotranspiration Models Derived From Global Eddy Flux Measurements And Remote Sensing Data, Yuan Fang, Ge Sun, Peter Caldwell, Steven G. Mcnulty, Asko Noormets, Jean-Christophe Domec, John King, Zhiqiang Zhang, Xudong Zhang, Guanghui Lin, Guangsheng Zhou, Jingfeng Xiao, Jiquan Chen Jan 2015

Monthly Land Cover-Specific Evapotranspiration Models Derived From Global Eddy Flux Measurements And Remote Sensing Data, Yuan Fang, Ge Sun, Peter Caldwell, Steven G. Mcnulty, Asko Noormets, Jean-Christophe Domec, John King, Zhiqiang Zhang, Xudong Zhang, Guanghui Lin, Guangsheng Zhou, Jingfeng Xiao, Jiquan Chen

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Evapotranspiration (ET) is arguably the most uncertain ecohydrologic variable for quantifying watershed water budgets. Although numerous ET and hydrological models exist, accurately predicting the effects of global change on water use and availability remains challenging because of model deficiency and/or a lack of input parameters. The objective of this study was to create a new set of monthly ET models that can better quantify landscape-level ET with readily available meteorological and biophysical information. We integrated eddy covariance flux measurements from over 200 sites, multiple year remote sensing products from the Moderate Resolution Imaging Spectroradiometer (MODIS), and statistical modelling. Through examining …


Scarification And Gap Size Have Interacting Effects On Northern Temperate Seedling Establishment, John L. Willis, Michael B. Walters, Kurt W. Gottschallk Jan 2015

Scarification And Gap Size Have Interacting Effects On Northern Temperate Seedling Establishment, John L. Willis, Michael B. Walters, Kurt W. Gottschallk

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

After decades focused on promoting economically valuable species, management of northern temperate forests has increasingly become focused on promoting tree species diversity. Unfortunately, many formerly common species that could contribute to diversity including yellow birch (Betula alleghaniensis Britton.), paper birch (Betula papyrifera Marsh), eastern hemlock (Tsuga canadensis L.), and eastern white pine (Pinus strobus L.) are now uncommon in the seedling layer, raising concerns about our ability to use these species to increase diversity. In this study, two related seed addition experiments conducted in 45 variably-sized harvest gaps (unharvested to 6500 m^2) in adjacent mesic northern hardwood stands, Emmet County, …


Neural Network Analysis On The Effect Of Heat Fluxes On Greenhouse Gas Emissions From Anaerobic Swine Waste Treatment Lagoon, N. Lovanh, J. Loughrin, M. Rysz, A. I. Quintanar, B. T. Oh, Rezaul Mahmood Jan 2015

Neural Network Analysis On The Effect Of Heat Fluxes On Greenhouse Gas Emissions From Anaerobic Swine Waste Treatment Lagoon, N. Lovanh, J. Loughrin, M. Rysz, A. I. Quintanar, B. T. Oh, Rezaul Mahmood

School of Natural Resources: Faculty Publications

No abstract provided.


Seagrass Meadows As A Globally Significant Carbonate Reservoir, I Mazarrasa, N Marbà, O Serrano, C E. Lovelock, Paul S. Lavery, J W. Fourqurean, H Kennedy, M A. Mateo, D Krause-Jensen, A D. Steven, C M. Duarte Jan 2015

Seagrass Meadows As A Globally Significant Carbonate Reservoir, I Mazarrasa, N Marbà, O Serrano, C E. Lovelock, Paul S. Lavery, J W. Fourqurean, H Kennedy, M A. Mateo, D Krause-Jensen, A D. Steven, C M. Duarte

Research outputs 2014 to 2021

There has been growing interest in quantifying the capacity of seagrass ecosystems to act as carbon sinks as a natural way of offsetting anthropogenic carbon emissions to the atmosphere. However, most of the efforts have focused on the particulate organic carbon (POC) stocks and accumulation rates and ignored the particulate inorganic carbon (PIC) fraction, despite important carbonate pools associated with calcifying organisms inhabiting the meadows, such as epiphytes and benthic invertebrates, and despite the relevance that carbonate precipitation and dissolution processes have in the global carbon cycle. This study offers the first assessment of the global PIC stocks in seagrass …


Correlation Analysis Of Climatic Variables, Migration And Dengue Cases In Southeast Florida, Brunilda Lugo Jan 2015

Correlation Analysis Of Climatic Variables, Migration And Dengue Cases In Southeast Florida, Brunilda Lugo

Walden Dissertations and Doctoral Studies

Dengue fever is a debilitating, viral, mosquito-borne disease occurring in tropical and subtropical areas in the world. The majority of dengue cases in the United States were acquired in endemic areas by travelers or immigrants. However, in recent years, autochthonous (locally acquired) dengue cases have been diagnosed in Florida. The purpose of this study was to find an association between potential risk factors and the expansion of dengue fever in the United States. Guided by the eco-bio-social framework, which offers a broad assessment of risk factors for the illness, a retrospective design was used with archival data to correlate changes …


Correlations Between Childhood Obesity And Obesogenic Environmental Variables Within Durham County, North Carolina, Eureka Capri Daye Jan 2015

Correlations Between Childhood Obesity And Obesogenic Environmental Variables Within Durham County, North Carolina, Eureka Capri Daye

Walden Dissertations and Doctoral Studies

The application of geographic information systems was used to map obesogenic conditions by zip code tabulation areas in Durham County, North Carolina and evaluated associations between those conditions and the understudied area of early childhood obesity. Of the thirty one percent of the children in Durham County, North Carolina who were considered obese in 2010, four hundred and thirty three (1:5) 2 - 4 year old children who received supplemental nutrition services for women, infants and children were obese with BMI levels greater or equal to the 95th percentile and were used as the criterion variable in the study (N=433). …


A Gis Assessment Of Ecoregion Representation In Chile's Existing And Proposed Integrated Network Of Protected Areas, Jessica Schutz Jan 2015

A Gis Assessment Of Ecoregion Representation In Chile's Existing And Proposed Integrated Network Of Protected Areas, Jessica Schutz

Graduate Student Theses, Dissertations, & Professional Papers

Chile's state designated protected areas are reported to show representation bias and to be unable to meet conservation goals. Private protected areas are considered an important tool to resolve these issues, which has led to support for increasing the role of private protected areas in Chile and creating an integrated public-private protected area network. But the validity of the capacity of private protected areas to fix Chile's state protected area network bias, and the advantage of creating an integrated protected area network, have not been assessed. This study uses the most recent data on Chile's state, private, and international protected …


Effect Of Neighborhood Features On Bmi Of African American Adolescents In South Los Angeles, Francisca Omelogo Obiora Jan 2015

Effect Of Neighborhood Features On Bmi Of African American Adolescents In South Los Angeles, Francisca Omelogo Obiora

Walden Dissertations and Doctoral Studies

Childhood obesity is a major national and worldwide public health crisis. The occurrence of childhood obesity, caused to large extent by an imbalance between caloric intake and caloric expenditure, has increased in the last 30 years. Although the prevalence of obesity has stabilized in recent years, it remains a top public health concern in the United States, especially in urban centers. The purpose of this study was to examine the associations between diet, physical activity, and the built environment in relation to the mean body mass index (BMI) of adolescents aged 12 to 17 years living in South Los Angeles, …


Financial Statement Disclosure Of Carbon Footprint Costs In The Airline Industry, Carol Anne Tuck-Riggs Jan 2015

Financial Statement Disclosure Of Carbon Footprint Costs In The Airline Industry, Carol Anne Tuck-Riggs

Walden Dissertations and Doctoral Studies

Unaccountable corporate polluters profit short term at the expense of global economic sustainability. The purpose of the study was to determine if carbon dioxide (CO2) penalties on the airline emissions would result in financial statement disclosure and emission mitigation. Contributing to environmental accounting, the study was based in corporate social responsibility with a conceptual framework based on economically-centered CO2 studies. A random sample of 69 global airlines, taken from the International Air Transport Association (IATA) and the International Civil Aviation Organization (ICAO) memberships, was stratified between EU bound and non-EU bound airlines. The research questions explored (a) the frequency mean …


Factors Affecting Emergency Manager, First Responder, And Citizen Disaster Preparedness, Tiffany Cooks Jan 2015

Factors Affecting Emergency Manager, First Responder, And Citizen Disaster Preparedness, Tiffany Cooks

Walden Dissertations and Doctoral Studies

Despite the increased frequency of natural and man-made disasters, there is a problem in the level of preparedness of emergency managers, responders, and citizens to address them. The purpose of this grounded theory study was to explore the factors that affect these groups' preparedness to inform the development of better emergency plans to handle emergency incidences. The conceptual framework for the study was knowledge management, which was used with a grounded theory approach. The study was guided by primary research questions that focused on understanding psychological, material, temporal, organizational, and other factors that affect the preparedness of emergency managers, first …