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Articles 3601 - 3630 of 6920
Full-Text Articles in Entire DC Network
Open-Source, Low-Cost Sensor For Custom Water Level Monitoring In Observation Wells And Piezometers, Leslie A. Mowbray
Open-Source, Low-Cost Sensor For Custom Water Level Monitoring In Observation Wells And Piezometers, Leslie A. Mowbray
Student Research Symposium
Many commercial sensors exist for monitoring water levels in piezometers and wells. However, these sensors tend to be expensive and contain proprietary hardware and software that make customization by users difficult. Recently, the vast open-source Arduino programming community has enabled the development of highly customizable, low cost sensors with the precision and accuracy needed for scientific research. Here, an ultrasonic distance sensor is developed to monitor the water level in a 2” piezometer with sub-centimeter resolution, powered by a lead-acid battery and solar cell to record sub-minute time increments for duration of days to weeks. This sensor was developed specifically …
Candy Flavorings In Tobacco, Jessica E. Brown, Wentai Luo, Lorne M. Isabelle, James F. Pankow
Candy Flavorings In Tobacco, Jessica E. Brown, Wentai Luo, Lorne M. Isabelle, James F. Pankow
Chemistry Faculty Publications and Presentations
Professor James F. Pankow reveals striking similarities between the patterns in the flavoring chemicals used in flavored tobacco products and those in popular candy and Kool-Aid products. The authors analyzed 12 artificially flavored candy and fruit drink products and compared them to 15 widely-available flavored tobacco products. They found significant overlap in the chemical signatures of the flavor chemicals. Several of the tobacco products contained flavor chemicals at much higher concentrations than in the non-tobacco products.
Assessing Hydrologic And Water Quality Sensitivities To Precipitation Changes, Urban Growth And Land Management Using Swat, Alexander Michael Psaris
Assessing Hydrologic And Water Quality Sensitivities To Precipitation Changes, Urban Growth And Land Management Using Swat, Alexander Michael Psaris
Dissertations and Theses
Precipitation changes and urban growth are two factors altering the state of water quality. Changes in precipitation will alter the amount and timing of flows, and the corresponding sediment and nutrient dynamics. Meanwhile, densification associated with urban growth will create more impervious surfaces which will alter sediment and nutrient loadings. Land and water managers often rely on models to develop possible future scenarios and devise management responses to these projected changes. We use the Soil and Water Assessment Tool (SWAT) to assess the sensitivities of stream flow, sediment, and nutrient loads in two urbanizing watersheds in Northwest Oregon, USA to …
Stochastic Order Relations Among Parallel Systems From Weibull Distributions, Nuria Torrado, Subhash C. Kochar
Stochastic Order Relations Among Parallel Systems From Weibull Distributions, Nuria Torrado, Subhash C. Kochar
Mathematics and Statistics Faculty Publications and Presentations
In this article, we focus on stochastic orders to compare the magnitudes of two parallel systems from Weibull distributions when one set of scale parameters majorizes the other. The new results obtained here extend some of those proved by Dykstra et al. (1997) and Joo and Mi (2010) from exponential to Weibull distributions. Also, we present some results for parallel systems from multiple-outlier Weibull models.
Modeling Historic Columbia River Flood Impacts, Lumas Helaire, Andrew Mahedy, Stefan A. Talke, David A. Jay
Modeling Historic Columbia River Flood Impacts, Lumas Helaire, Andrew Mahedy, Stefan A. Talke, David A. Jay
Civil and Environmental Engineering Faculty Publications and Presentations
The Lower Columbia River Estuary (LCRE) has undergone extensive modifications since the 19th century. Construction of dams, installation of jetties and dikes, dredging of the navigation channel and filling in of tidal wetlands have all contributed significantly to alterations in tidal dynamics and the flow regime, with consequences for habitat inundation and salinity intrusion. In this talk we discuss the development and implementation of a 19th century flow model for the LCRE, using a digital elevation model based on historic bathymetry. The model has been calibrated with recently rediscovered and digitized tide data from the 19th century. …
Impact Of Soil Moisture–Atmosphere Interactions On Surface Temperature Distribution, Alexis Berg, Benjamin R. Lintner, Kirsten L. Findell, Sergey Malyshev, Paul C. Loikith, Pierre Gentine
Impact Of Soil Moisture–Atmosphere Interactions On Surface Temperature Distribution, Alexis Berg, Benjamin R. Lintner, Kirsten L. Findell, Sergey Malyshev, Paul C. Loikith, Pierre Gentine
Geography Faculty Publications and Presentations
Understanding how different physical processes can shape the probability distribution function (PDF) of surface temperature, in particular the tails of the distribution, is essential for the attribution and projection of future extreme temperature events. In this study, the contribution of soil moisture–atmosphere interactions to surface temperature PDFs is investigated. Soil moisture represents a key variable in the coupling of the land and atmosphere, since it controls the partitioning of available energy between sensible and latent heat flux at the surface. Consequently, soil moisture variability driven by the atmosphere may feed back onto the near-surface climate—in particular, temperature. In this study, …
Portland State Magazine, Portland State University. Office Of University Communications
Portland State Magazine, Portland State University. Office Of University Communications
Portland State Magazine
PSU’s alumni magazine, published 2-3 times a year. In this issue: Writer and alumnus Mitchell Jackson found his voice and a path leading away from drug dealing and prison; launching a product is more complicated than you think; for it 50th anniversary, the School of Social Work shows off its alumni; “zombie viruses” could lead to better vaccines; life will never be the same for study abroad student Seth O’Malley; a new, independent governing board for Portland State; and more.
Searching For Biogeochemical Hot Spots In Three Dimensions: Soil C And N Cycling In Hydropedologic Settings In A Northern Hardwood Forest, Jennifer L. Morse, S F. Werner, Cody P. Gillin, Christine L. Goodale, Scott W. Bailey, Kevin J. Mcguire, Peter M. Groffman
Searching For Biogeochemical Hot Spots In Three Dimensions: Soil C And N Cycling In Hydropedologic Settings In A Northern Hardwood Forest, Jennifer L. Morse, S F. Werner, Cody P. Gillin, Christine L. Goodale, Scott W. Bailey, Kevin J. Mcguire, Peter M. Groffman
Environmental Science and Management Faculty Publications and Presentations
Understanding and predicting the extent, location, and function of biogeochemical hot spots at the watershed scale is a frontier in environmental science. We applied a hydropedologic approach to identify (1) biogeochemical differences among morphologically distinct hydropedologic settings and (2) hot spots of microbial carbon (C) and nitrogen (N) cycling activity in a northern hardwood forest in Hubbard Brook Experimental Forest, New Hampshire, USA. We assessed variables related to C and N cycling in spodic hydropedologic settings (typical podzols, bimodal podzols, and Bh podzols) and groundwater seeps during August 2010. We found that soil horizons (Oi/Oe, Oa/A, and B) differed significantly …
A Facile Route To Tailoring Peptide-Stabilized Gold Nanoparticles Using Glutathione As A Synthon, Rosina Ho Wu, Tan P. Nguyen, Grant W. Marquart, Thomas J. Miesen, Theresa Mau, Marilyn R. Mackiewicz
A Facile Route To Tailoring Peptide-Stabilized Gold Nanoparticles Using Glutathione As A Synthon, Rosina Ho Wu, Tan P. Nguyen, Grant W. Marquart, Thomas J. Miesen, Theresa Mau, Marilyn R. Mackiewicz
Chemistry Faculty Publications and Presentations
The preparation of gold nanoparticles (AuNPs) of high purity and stability remains a major challenge for biological applications. This paper reports a simple synthetic strategy to prepare water-soluble peptide-stabilized AuNPs. Reduced glutathione, a natural tripeptide, was used as a synthon for the growth of two peptide chains directly on the AuNP surface. Both nonpolar (tryptophan and methionine) and polar basic (histidine and dansylated arginine) amino acids were conjugated to the GSH-capped AuNPs. Ultracentrifugation concentrators with polyethersulfone (PES) membranes were used to purify precursor materials in each stage of the multi-step synthesis to minimize side reactions. Thin layer chromatography, transmission electron …
The Impact Of Surface Ligands And Synthesis Method On The Toxicity Of Glutathione-Coated Gold Nanoparticles, Bryan Harper, Federico Sinche, Meenambika Gowrishankar, Grant Marquart, Marilyn R. Mackiewicz, Stacey L. Harper
The Impact Of Surface Ligands And Synthesis Method On The Toxicity Of Glutathione-Coated Gold Nanoparticles, Bryan Harper, Federico Sinche, Meenambika Gowrishankar, Grant Marquart, Marilyn R. Mackiewicz, Stacey L. Harper
Chemistry Faculty Publications and Presentations
Gold nanoparticles (AuNPs) are increasingly used in biomedical applications, hence understanding the processes that affect their biocompatibility and stability are of significant interest. In this study, we assessed the stability of peptide-capped AuNPs and used the embryonic zebrafish (Danio rerio) as a vertebrate system to investigate the impact of synthesis method and purity on their biocompatibility. Using glutathione (GSH) as a stabilizer, Au-GSH nanoparticles with identical core sizes were terminally modified with Tryptophan (Trp), Histidine (His) or Methionine (Met) amino acids and purified by either dialysis or ultracentrifugation. Au-GSH-(Trp)2 purified by dialysis elicited significant morbidity and mortality at …
Anisotropy Of The Reynolds Stress Tensor In The Wakes Of Counter-Rotating Wind Turbine Arrays, Nicholas Michael Hamilton
Anisotropy Of The Reynolds Stress Tensor In The Wakes Of Counter-Rotating Wind Turbine Arrays, Nicholas Michael Hamilton
Dissertations and Theses
A wind turbine array was constructed in the wind tunnel at Portland State University in a standard Cartesian arrangement. Configurations of the turbine array were tested with rotor blades set to rotate in either a clockwise or counter-clockwise sense. Measurements of velocity were made with stereo particle-image velocimetry. Mean statistics of velocities and Reynolds stresses clearly show the effect of direction of rotation of rotor blades for both entrance and exit row turbines. Rotational sense of the turbine blades is visible in the mean spanwise velocity W and the Reynolds shear stress -[macron over vw]. The normalized anisotropy tensor was …
Copernicus’ Role In The Scientific Revolution: Philosophical Merits And Influence On Later Scientists, Jonathan Huston
Copernicus’ Role In The Scientific Revolution: Philosophical Merits And Influence On Later Scientists, Jonathan Huston
Young Historians Conference
Nicolaus Copernicus' publication of De Revolutionibus Orbium Coesltium marks the beginning of a revolution in the field of astronomy and physics. Within 150 years, a heliocentric system became almost universally accepted in the scientific community. Copernicus’ model was significant not because it of its scientific merit, but because of its ideological appeal to scientists during the 16th through 18th century. This paper explores the philosophical foundations of Copernicus' model, and examines his influence in later work of four significant astronomers and physicists, Brahe, Kepler, Galileo, and Newton.
Interpretation Of Chemical Environments By Rna And The Implications To The Origins Of Life, Brian Larson
Interpretation Of Chemical Environments By Rna And The Implications To The Origins Of Life, Brian Larson
Dissertations and Theses
We describe the initial realization of behavior in the biosphere, which we term behavioral chemistry. If molecules are complex enough to attain a stochastic element to their structural conformation in such a way as to radically affect their function in a biological (evolvable) setting, then they have the capacity to behave. This circumstance is described here as behavioral chemistry, unique in its definition from the colloquial chemical behavior. This transition between chemical behavior and behavioral chemistry need be explicit when discussing the root cause of behavior, which itself lies squarely at the origins of life and is the foundation of …
Associations Between Input And Outcome Variables In An Online High School Bioinformatics Instructional Program, Douglas S. Lownsbery
Associations Between Input And Outcome Variables In An Online High School Bioinformatics Instructional Program, Douglas S. Lownsbery
Dissertations and Theses
Quantitative data from a completed year of an innovative online high school bioinformatics instructional program were analyzed as part of a descriptive research study. The online instructional program provided the opportunity for high school students to develop content understandings of molecular genetics and to use sophisticated bioinformatics tools and methodologies to conduct authentic research. Quantitative data were analyzed to identify potential associations between independent program variables including implementation setting, gender, and student educational backgrounds and dependent variables indicating success in the program including completion rates for analyzing DNA clones and performance gains from pre-to-post assessments of bioinformatics knowledge. Study results …
Relationships Between Environmental Governance And Water Quality In A Growing Metropolitan Area Of The Pacific Northwest, Usa, Heejun Chang, Paul R. Thiers, Noelwah R. Netusil, J. Alan Yeakley, Gretchen Rollwagen-Bollens, Steve Bollens, Sonia Singh
Relationships Between Environmental Governance And Water Quality In A Growing Metropolitan Area Of The Pacific Northwest, Usa, Heejun Chang, Paul R. Thiers, Noelwah R. Netusil, J. Alan Yeakley, Gretchen Rollwagen-Bollens, Steve Bollens, Sonia Singh
Geography Faculty Publications and Presentations
We investigate relationships between environmental governance and water quality in two adjacent growing metropolitan areas in the western US. While the Portland, Oregon and Vancouver, Washington metro areas share many common biophysical characteristics, they have different land development histories and water governance structures, providing a unique opportunity for examining how differences in governance might affect environmental quality. We conceptualize possible linkages in which water quality influences governance directly, using monitoring efforts as a metric, and indirectly by using the change in the sale price of single-family residential properties. Governance may then influence water quality directly through riparian restoration resulting from …
Household Water Demand And Land Use Context: A Multilevel Approach, Elizabeth Yancey Breyer
Household Water Demand And Land Use Context: A Multilevel Approach, Elizabeth Yancey Breyer
Dissertations and Theses
Urban water use arises from a mix of scale-dependent biophysical and socioeconomic factors. In Portland, Oregon, single-family residential water use exhibits a tightly coupled relationship with summertime weather, although this relationship varies with land use patterns across households and neighborhoods. This thesis developed a multilevel regression model to evaluate the relative importance of weather variability, parcel land use characteristics, and neighborhood geographic context in explaining single-family residential water demand patterns in the Portland metropolitan area. The model drew on a high-resolution panel dataset of weekly mean summer water use over five years (2001-2005) for a sample of 460 single-family households …
Learning Two-Input Linear And Nonlinear Analog Functions With A Simple Chemical System, Peter Banda, Christof Teuscher
Learning Two-Input Linear And Nonlinear Analog Functions With A Simple Chemical System, Peter Banda, Christof Teuscher
Computer Science Faculty Publications and Presentations
The current biochemical information processing systems behave in a predetermined manner because all features are defined during the design phase. To make such unconventional computing systems reusable and programmable for biomedical applications, adaptation, learning, and self-modification baaed on external stimuli would be highly desirable. However, so far, it haa been too challenging to implement these in real or simulated chemistries. In this paper we extend the chemical perceptron, a model previously proposed by the authors, to function as an analog instead of a binary system. The new analog asymmetric signal perceptron learns through feedback and supports MichaelisMenten kinetics. The results …
A Missing Piece In The Sustainability Movement: The Human Spirit, Deborah S. Peterson
A Missing Piece In The Sustainability Movement: The Human Spirit, Deborah S. Peterson
Educational Leadership and Policy Faculty Publications and Presentations
The sustainability movement, committed to the health of our natural world, is making a critical contribution to society. While many agree the sustainability movement should focus on the natural world, recent articles call for an additional focus on human welfare. This article proposes that a missing piece of the sustainability movement is a discussion of the role of the human spirit. By focusing narrowly on an examination of the state of the natural world, we are neglecting to incorporate the deep and enduring power of the human spirit to transform our natural and human-made environment and to support change agents …
The Effectiveness Of Forest Collaborative Groups At Reducing The Likelihood Of Project Appeals And Objections In Eastern Oregon, Brent M. Summers
The Effectiveness Of Forest Collaborative Groups At Reducing The Likelihood Of Project Appeals And Objections In Eastern Oregon, Brent M. Summers
Environmental Science and Management Professional Master's Project Reports
Collaborative planning has been used as a tool to address wicked natural resource conflicts and engage those affected by federal land management agency decisions. The United States Forest Service (USFS) is mandated by law to involve the public on project-level planning. In Oregon, Forest Collaborative Groups have been engaging with the USFS to involve stakeholders who are concerned with the activities on National Forests. It is widely believed that these groups are reducing project-level appeals and objections (appeals); however, there is no empirical evidence to validate these beliefs. National Environmental Protect Act (NEPA) document data were collected from the USFS …
An Analysis Of The Practical Dpg Method, Jay Gopalakrishnan, Weifeng Qiu
An Analysis Of The Practical Dpg Method, Jay Gopalakrishnan, Weifeng Qiu
Mathematics and Statistics Faculty Publications and Presentations
We give a complete error analysis of the Discontinuous Petrov Galerkin (DPG) method, accounting for all the approximations made in its practical implementation. Specifically, we consider the DPG method that uses a trial space consisting of polynomials of degree p on each mesh element. Earlier works showed that there is a "trial-to-test" operator T, which when applied to the trial space, defines a test space that guarantees stability. In DPG formulations, this operator T is local: it can be applied element-by-element. However, an infinite dimensional problem on each mesh element needed to be solved to apply T. In practical computations, …
Modelling Rainwater-Harvesting System Reliability Based On Historical Precipitation Data For Portland, Mrinali Mathur
Modelling Rainwater-Harvesting System Reliability Based On Historical Precipitation Data For Portland, Mrinali Mathur
Civil and Environmental Engineering Master's Project Reports
Rainwater harvesting can ease the water availability problems for many parts of the world where water is not easily available. It is also a solution for minimizing stormwater runoff and better managing sewers by preventing combined sewers to overflow. The goal of this project is to calculate the reliability of rainwater harvesting systems and provide optimum size of the storage tank using historical records for Portland specific rain pattern. A simple water balance approach for historical data is used to calculate the reliability by which rainwater harvesting system can be used as a means of irrigating gardens in Portland. The …
Research & Strategic Partnerships: Quarterly Review, Volume 1, Issue 3, Portland State University. Research & Strategic Partnerships
Research & Strategic Partnerships: Quarterly Review, Volume 1, Issue 3, Portland State University. Research & Strategic Partnerships
Portland State Research Magazine
This edition of RSP Quarterly Review focuses on programs that connect Portland State’s education researchers with their community partners. Improving STEM (Science Technology Engineering and Math) education has emerged as a critical component of technology- dominated economic development across the U.S., including here in Oregon.
Osmb Final Report, Task 7: Online Atlas Of Oregon Lakes - Aquatic Invasive Species Interface, Rich Miller, Mark D. Sytsma
Osmb Final Report, Task 7: Online Atlas Of Oregon Lakes - Aquatic Invasive Species Interface, Rich Miller, Mark D. Sytsma
Center for Lakes and Reservoirs Publications and Presentations
In order to educate a broad cross section of the public about Aquatic Invasive Species (AIS) distributions and survey efforts in Oregon’s lakes and reservoirs, database connections were created to display AIS information on the Online Atlas of Oregon Lakes (aol.research.pdx.edu/). The connections allowed for the dynamic display of AIS survey records stored in three separate databases: the Center for Lakes and Reservoir’s Oregon Aquatic Plant and Mussel Databases and the iMapInvasives database. AIS survey records collected by the Center for Lakes and Reservoirs were also reported to the iMapInvasives database.
Streamflow Modeling Of Johnson Creek Subwatersheds Using The Precipitation Runoff Modeling System, Theophilus Matthew Malone
Streamflow Modeling Of Johnson Creek Subwatersheds Using The Precipitation Runoff Modeling System, Theophilus Matthew Malone
Civil and Environmental Engineering Master's Project Reports
Johnson Creek, in the Portland, Oregon metropolitan region, has several pollutants on the U.S. Environmental Protection Agency's (EPA) 303(d) list including excess heat, low dissolved oxygen, and harmful bacteria. Understanding streamflow response to precipitation events is an important component to evaluating water quality trends and calculating the Total Maximum Daily Load (TMDL) for pollutants of concern. Investigating the streamflow-precipitation relationship on the subwatershed scale can give insight to the hydrologic response of a given watershed. However, developing rating curves for several subwatersheds can be cost and time prohibitive. The objective of this project was to develop a hydrologic model using …
Near-Surface Internal Melting: A Substantial Mass Loss On Antarctic Dry Valley Glaciers, Matthew J. Hoffman, Andrew G. Fountain, Glen E. Liston
Near-Surface Internal Melting: A Substantial Mass Loss On Antarctic Dry Valley Glaciers, Matthew J. Hoffman, Andrew G. Fountain, Glen E. Liston
Geology Faculty Publications and Presentations
The McMurdo Dry Valleys, southern Victoria Land, East Antarctica, are a polar desert, and melt from glacial ice is the primary source of water to streams, lakes and associated ecosystems. Previous work found that to adequately model glacier ablation and subsurface ice temperatures with a surface energy-balance model required including the transmission of solar radiation into the ice. Here we investigate the contribution of subsurface melt to the mass balance of (and runoff from) Dry Valley glaciers by including a drainage process in the model and applying the model to three glacier sites using 13years of hourly meteorological data. Model …
Serial Transfer Can Aid The Evolution Of Autocatalytic Sets, Wim Hordijk, Nilesh Vaidya, Niles Lehman
Serial Transfer Can Aid The Evolution Of Autocatalytic Sets, Wim Hordijk, Nilesh Vaidya, Niles Lehman
Chemistry Faculty Publications and Presentations
Background: The concept of an autocatalytic set of molecules has been posited theoretically and demonstrated empirically with catalytic RNA molecules. For this concept to have significance in a realistic origins-of-life scenario, it will be important to demonstrate the evolvability of such sets. Here, we employ a Gillespie algorithm to improve and expand on previous simulations of an empirical system of self-assembling RNA fragments that has the ability to spontaneously form autocatalytic networks. We specifically examine the role of serial transfer as a plausible means to allow time-dependent changes in set composition, and compare the results to equilibrium, or "batch" scenarios. …
Osmb Final Report, Task 4: Oregon Lake Watch, Angela L. Strecker, Rich Miller, Vanessa Morgan
Osmb Final Report, Task 4: Oregon Lake Watch, Angela L. Strecker, Rich Miller, Vanessa Morgan
Center for Lakes and Reservoirs Publications and Presentations
The Oregon Lake Watch (OLW) volunteer monitoring program was resurrected after over a decade in hibernation. The new program was designed to educate the public about threats of aquatic invasive species (AIS), provide early detection of AIS invasions, and provide long term water quality data for the better management of Oregon’s lakes and reservoirs. Protocols were created for citizen scientists to survey for AIS, collect temperature and water clarity data, and record the data through an online data entry portal. An OLW website was developed to educate about AIS and provide survey protocols and identification materials to volunteers. AIS surveys …
Four Decades Of Systems Science Teaching And Research In The Usa At Portland State University, Wayne Wakeland
Four Decades Of Systems Science Teaching And Research In The Usa At Portland State University, Wayne Wakeland
Complex Systems Faculty Publications and Presentations
Systems science is defined in general fashion, and a brief background is provided that lists some of the systems science-related societies, conferences, journals, research institutes, and educational programs. The Systems Science Graduate Program at Portland State University in Portland, OR, USA, is described in detail, including its history, curriculum, students, faculty, and degrees granted. Dissertation topics are summarized via word diagrams created from dissertation titles over the years. MS degrees, student placement, and undergraduate courses are also mentioned, and future plans for the program are described including its support for sustainability education.
The Role Of Network Position For Peer Influences On Adolescents' Academic Engagement, Price Mccloud Johnson
The Role Of Network Position For Peer Influences On Adolescents' Academic Engagement, Price Mccloud Johnson
Dissertations and Theses
Academic engagement has been found to significantly predict students' future achievement. Among adolescents, the peer context becomes an increasingly important point of socialization and influence on beliefs and behavior, including academic engagement. Previous research suggests that those peers with whom an adolescent spends much of their time significantly predict change in engagement over time (Kindermann, 2007). Bronfenbrenner's ecological systems theory (Bronfenbrenner & Morris, 1998) postulates that exosystem effects (those influencing factors that are not directly connected to individuals) play an important role in development, and social network theorists have suggested that the position one occupies within the greater network is …
Assessing The Homogenization Of Urban Land Management With An Application To Us Residential Lawn Care, Colin Polsky, J. Morgan Grove, Chris Knudson, Peter M. Groffman, Neil D. Bettez, Jeannine Cavender-Bares, Sharon J. Hall, James B. Heffernan, Sarah E. Hobbie, Kelli L. Larson, Jennifer L. Morse, Christopher Neill, Kristen C. Nelson, Laura A. Ogden, Jarlath O'Neil-Dunne, Diane E. Pataki, Rinku Roy Chowdhury, Meredith K. Steele
Assessing The Homogenization Of Urban Land Management With An Application To Us Residential Lawn Care, Colin Polsky, J. Morgan Grove, Chris Knudson, Peter M. Groffman, Neil D. Bettez, Jeannine Cavender-Bares, Sharon J. Hall, James B. Heffernan, Sarah E. Hobbie, Kelli L. Larson, Jennifer L. Morse, Christopher Neill, Kristen C. Nelson, Laura A. Ogden, Jarlath O'Neil-Dunne, Diane E. Pataki, Rinku Roy Chowdhury, Meredith K. Steele
Environmental Science and Management Faculty Publications and Presentations
Changes in land use, land cover, and land management present some of the greatest potential global environmental challenges of the 21st century. Urbanization, one of the principal drivers of these transformations, is commonly thought to be generating land changes that are increasingly similar. An implication of this multiscale homogenization hypothesis is that the ecosystem structure and function and human behaviors associated with urbanization should be more similar in certain kinds of urbanized locations across biogeophysical gradients than across urbanization gradients in places with similar biogeophysical characteristics. This paper introduces an analytical framework for testing this hypothesis, and applies the framework …