Social and Behavioral Sciences Commons^™

Structural Equation Modeling Of Dynamics Of Nitrate Contamination In Groundwater, Zhi-Jun Liu, George R. Hallberg, George P. Malanson

George P Malanson

Most research on the temporal aspect of nitrate pollution in water resources has focused on surface water. Comprehensive studies on the dynamics of nitrate in ground water are lacking, especially on a drainage basin scale and for relatively long periods of time. In this study, structural equation modeling is applied in investigating the influences of climate, hydrology, and nitrogen management in agricultural production on nitrate concentration in the Big Spring Basin, Iowa, over a 10-year period. The study shows that for given hydrogeological settings, nitrogen management practices and climate are the two most important factors that affect nitrate dynamics. The …

Post-Fire Succession In Californian Coastal Sage Scrub: The Role Of Continual Basal Sprouting., George P. Malanson, W. E. Westman

George P Malanson

Dominant shrub species of coastal sage scrub in coastal southern Cali- fornia are able to produce shoots from their base on a continual basis in the absence of fire or other major defoliation. As a result, each shrub becomes a population of mixed-aged branches (ramets) and extends its duration in the canopy beyond the age of any of its above-ground phytomass, reduces the incidence of senescence, and per- mits an individual (genet) to survive during long fire-free intervals. A computer sim- ulation of succession in coastal sage scrub under differing fire intervals shows that continual basal sprouting may be significant …

Effects Of Terrain On Excessive Travel Distance By Snow Avalanches, George P. Malanson

George P Malanson

No abstract provided.

Transverse Pattern Of Vegetation On Avalanche Paths In The Northern Rocky Mountains, Montana., George P. Malanson, D. R. Butler

George P Malanson

No abstract provided.

Flood Frequency And The Assemblage Of Dispersal Types In Hanging Gardens Of The Narrows, Zion National Park, Utah, George P. Malanson, J. Kay

George P Malanson

No abstract provided.

Improving Environmental Simulation Models To Assess Climate Change Impacts, George P. Malanson, Marc P. Armstrong

George P Malanson

Increased levels of atmospheric carbon dioxide and other by-products of human civilization are expected to disrupt the global energy budget and induce climatic change, which will aIter the distribution of plant species and the composition of plant communities. In spite of the importance of these projected effects, our understanding of the processes leading to such changes needs to be strengthened. This paper addresses the need to improve models that are used to assess spatial aspects of the response of vegetation to anthropogenic climate change. Several modifications are suggested, each of which relates to changes in forest community composition that occur …

Identifying The Biodiversity Research Needs Related To Forest Fragmentation, George P. Malanson, John A. Kupfer, Scott B. Franklin

George P Malanson

No abstract provided.

Woody Debris, Sediment, And Riparian Vegetation Of A Subalpine River, Montana, Usa., George P. Malanson, D. R. Butler

George P Malanson

No abstract provided.

Farm Chemicals As Indicators Of Sediment Sources In Iowa Rivers, George P. Malanson, E. N. Nealson

George P Malanson

Determination of the source of sediment in rivers and streams is important in order to effectively implement a program to reduce its concentration. This project uses agricultural chemicals as indicators of current sources of sediment from farm fields in the Cedar River, Iowa watershed. We hypothesized that the relations of sediment, nitrogen, and phosphorous yields to precipitation would indicate whether sediment originated from erosion of fields or from channel bank erosion of floodplains. The changes in sediment, nitrate, and phosphorus in the channel in response to rainfall events were determined. In simple regressions, all three variables have similar slopes when …

Ordination Of Woody Vegetation In A Ouachita National Forest Watershed, George Malanson, Denise Marion

George P Malanson

Species response to competition and other environmental gradients has important implications for forest ecosystem managers who desire to both maintain diversity and provide a sustained flow of forest goods and services. Woody species on a 140-acre watershed in the Ouachita National Forest are ordinated with detrended correspondence analysis (DCA) and canonical correspondence analysis (CCA) to identify the important influences on species distribution at this scale. Species composition is found to respond primarily to a moisture gradient, and secondarily to competition with shortleaf pine (Pinus echinata Mill.). Centrifugal organization of species along gradients is suggested by the relative locations of species …

Habitat And Plant Distributions In Hanging Gardens Of The Narrows, Zion National Park, Utah, George P. Malanson

George P Malanson

No abstract provided.

Reinterpretation Of Relations Between Vegetation Removal And Water Yield, George P. Malanson, D. P. Post

George P Malanson

While the relation between vegetation clearance and increasing streamflow appears to be strong for data aggregated among geographic regions, results are equivocal in local areas. Earlier data are re-analyzed to consider the role of hydroclimatology. While vegetation clearance increases absolute streamflow, the proportional change is not significant. Residuals of regressions of absolute and proportional change in streamflow on vegetation clearance are related to precipitation, with positive and negative slopes, respectively. A few outliers with high responses are important in creating a pattern, and hydroclimatology is a better predictor of change in streamflow than is vegetation clearance for aggregate data. With …

Peasant Farming: Commoning Through Co-Production For Future Generations, Luigi Russi

Luigi Russi

The chapter examines the rift existing between peasant modes of production and the productionist paradigm in agriculture. While the former is based on co-production - i.e. the material negotiation of symbiotic relationships with ecological cycles - the latter attempts to format agriculture so as to make it amenable to a standard of control comparable to that of factory processes. By re-opening developmental possibilities that are closed off by the productionist paradigm, peasant co-production enacts instances of situated counterwork and commoning, through which new forms of ecological intergenerational justice can be attained.

Community-Level Characteristics Associated With Variations In Rates Of Homelessness Among Families And Single Adults, Jamison D. Fargo, Ellen A. Munley, Thomas H. Byrne, Ann Elizabeth Montgomery, Dennis P. Culhane

Dennis P. Culhane

Analysis Of The Spatial And Temporal Dynamics Of Street Hawking: A Case Study Of The Accra Metropolitan Area, Alex Owusu Barimah, Stephen Abrokwah, Stephen Frimpong

Stephen Frimpong

To the street hawker, it is a means of making a living but to the managers of the metropolis, street hawking is a menace. These differences in perception have led to a game plan tied to spatio-temporal diurnal traffic regimes. While the city authorities plan may be to evict the street hawkers, the plan of the hawkers is to outwit the city authorities through make-shift hawking patterns in order to make a living. The difference in the two positions can be characterized by the city manager’s need for clean and less congested city streets, and the hawker’s desire to sell …

Walking In The Land Of Cars: Automobile-Pedestrian Accidents In Hillsborough County, Florida, Marc Aaron Poling

Marc A Poling

Analyses of traffic accidents are often focused on the characteristics of the accident event and hence do not take into account the broader neighborhood contexts in which accidents are located. This thesis seeks to extend empirical analyses of accidents by understanding the link between accidents and their surroundings. The case study for this thesis is Hillsborough County, Florida, within which the city of Tampa is located. The Tampa Bay region ranks very high in terms of accident rates within U.S. metropolitan areas and is also characterized by transport policies which favor private automobiles over mass transit options, making it an …

Quantitative Assessment Method Of Illegal Dumping În Small Rivers. Case Study: Neamt County, Romania, Florin C. Mihai

Florin C MIHAI

Poor waste management facilities from Romanian rural areas lead to uncontrolled waste disposal on improper sites. These bad practices are frequently in the the proximity of built-up areas , therefore, the small rivers inside these areas are susceptible to waste dumping. The paper aims to develop a quantitative assessment method of waste disposed into such small rivers from extra Carpathian region of Neamț county. The lack of organized waste collection services from 2003 lead to high values of waste disposed in such rivers frequently over 15 t/yr for each one. Despite some improvements compared to 2003 the small rivers inside …

Parcel-Level Redevelopment Strategies For Distressed Neighborhoods, Michael P. Johnson Jr., Justin Hollander

Michael P. Johnson

Certain distressed neighborhoods cannot support traditional residential-focused development. For these communities, we develop decision models for acquisition and redevelopment of chronically vacant lands and structures for primarily non-residential and greening uses. We address social benefits and costs of redevelopment strategies, parcel clustering to exploit economies of scale, and conflicting values among stakeholders. We illustrate our models using data from Baltimore, MD.

Evaluating Emergency Management After An Event: Gaps And Suggestions, Neil Dufty

Neil Dufty

Post-event evaluations of emergency management are critical to help emergency service providers and communities learn to build disaster resilience. This paper identifies five main types of formal post-event evaluations of emergency management that are used in Australia. It argues that these evaluations should be more consistent in their conduct and approach, more comprehensive in scope, and better timed. The paper also suggests that post-event evaluation reports should be released particularly to the affected communities.

Internal And External Commuting And Their Role In Explaining Demographic Change In Nonmetropolitan Areas: A Case Study Of Simcoe County, Ontario, 1971-1991, Robert Gregory Atkinson

Robert G. Atkinson

Since the 1970's, nonmetropolitan areas have grown at rates in excess of those experienced by metropolitan areas. Two opposing arguments have been put forth in attempting to explain such a trend. Such arguments focus on the processes of counterurbanisation and metropolitan overspill. This paper ascertains to what extent these processes determine population change in Simcoe County, Ontario, between the years of 1971 and 1991. Associated physical factors, such as metropolitan distance and accessibility, settlement size, and settlement form, are all assessed. Emphasis, however, is placed on an examination of internal and external commuting patterns and their role in explaining recent …

Tb182: Agricultural Land Changes In Maine: A Compilation And Brief Analysis Of Census Of Agriculture Data, 1850-1997, Soeun Ahn, William B. Krohn, Andrew J. Plantinga, Timothy J. Dalton

William B. Krohn

The purpose of this study is to compile the best available long-term historical information on agricultural land use in Maine and to briefly analyze these data to develop a statewide description of Maine's land use history from the mid-1800s to present. Our emphasis is on compiling statistically based information and, in particular, land use data reported in the Census of Agriculture. Objectives were (1) to compile available statewide data on agricultural land and land cover (LULC) in Maine, 1850-1997; (2) to examine temporal and spatial patterns in the LULC of Maine; and (3) to discuss the implications of the major …

Monte Carlo Simulations Of Electromagnetic Wave Scattering From A Random Rough Surface With Three-Dimensional Penetrable Buried Object: Mine Detection Application Using The Steepest-Descent Fast Multipole Method, Magda El-Shenawee, Carey Rappaport, Michael Silevitch

Carey Rappaport

We present a statistical study of the electric field scattered from a three-dimensional penetrable object buried under a two-dimensional random rough surface. Monte Carlo simulations using the steepest-descent fast multipole method (SDFMM) are conducted to calculate the average and the standard deviation of the near-zone scattered fields. The SDFMM, originally developed at the University of Illinois at Urbana–Champaign, has been modified to calculate the unknown surface currents both on the rough ground and on the buried object that are due to excitation by a tapered Gaussian beam. The rough ground medium used is an experimentally measured typical dry Bosnian soil …

Monte Carlo Simulations Of Electromagnetic Wave Scattering From A Random Rough Surface With Three-Dimensional Penetrable Buried Object: Mine Detection Application Using The Steepest-Descent Fast Multipole Method, Magda El-Shenawee, Carey Rappaport, Michael Silevitch

Michael B. Silevitch

We present a statistical study of the electric field scattered from a three-dimensional penetrable object buried under a two-dimensional random rough surface. Monte Carlo simulations using the steepest-descent fast multipole method (SDFMM) are conducted to calculate the average and the standard deviation of the near-zone scattered fields. The SDFMM, originally developed at the University of Illinois at Urbana–Champaign, has been modified to calculate the unknown surface currents both on the rough ground and on the buried object that are due to excitation by a tapered Gaussian beam. The rough ground medium used is an experimentally measured typical dry Bosnian soil …

Experimental Validation Of A Numerical Forward Model For Tunnel Detection Using Cross-Borehole Radar, Arvin Farid, Jose A. Martinez-Lorenzo, Akram N. Alshawabkeh, Carey M. Rappaport

Jose Martinez-Lorenzo

The goal of this research is to develop an experimentally validated two-dimensional(2D) finite difference frequency domain (FDFD) numerical forward model to studythe potential of radar-based tunnel detection. Tunnel detection has become a subject of interest to the nation due to the use of tunnels by illegal immigrants, smugglers, prisoners, assailants, and terrorists. These concerns call for research to nondestructively detect, localize, and monitor tunnels. Nondestructive detection requires robust image reconstruction and inverse models, which in turn need robust forward models. Cross-Well Radar (CWR) modality is used for experimentation to avoid soil-air interface roughness. CWR is not a versatile field technology …

Cross-Well Radar. I: Experimental Simulation Of Cross-Well Tomography And Validation, Arvin Farid, Akram N. Alshawabkeh, Carey M. Rappaport

Akram N. Alshawabkeh

This paper explains and evaluates the potential and limitations of conducting cross-well radar (CWR) in sandy soils. Implementing the experiment and data collection in the absence of any scattering object, and in the presence of an acrylic plate [a representative of dielectric objects, such as dense nonaqueous phase liquid (DNAPL) pools, etc.], as a contrasting object in a water-saturated soil is also studied. To be able to image the signature of any object, more than one pair of receiving and transmitting antennas are required. The paper describes a method to achieve repeatable, reliable, and reproducible laboratory results for different transmitter-receiver …

Experimental Validation Of A Numerical Forward Model For Tunnel Detection Using Cross-Borehole Radar, Arvin Farid, Jose A. Martinez-Lorenzo, Akram N. Alshawabkeh, Carey M. Rappaport

Akram N. Alshawabkeh

The goal of this research is to develop an experimentally validated two-dimensional(2D) finite difference frequency domain (FDFD) numerical forward model to studythe potential of radar-based tunnel detection. Tunnel detection has become a subject of interest to the nation due to the use of tunnels by illegal immigrants, smugglers, prisoners, assailants, and terrorists. These concerns call for research to nondestructively detect, localize, and monitor tunnels. Nondestructive detection requires robust image reconstruction and inverse models, which in turn need robust forward models. Cross-Well Radar (CWR) modality is used for experimentation to avoid soil-air interface roughness. CWR is not a versatile field technology …

Cross-Well Radar. Ii: Comparison And Experimental Validation Of Modeling Channel Transfer Function, Arvin Farid, Sophia H. Zhan, Akram N. Alshawabkeh, Carey M. Rappaport

Carey Rappaport

Close agreement between theory and experiment is critical for adequate understanding and implementation of the cross-well radar (otherwise known as cross-borehole ground penetrating radar) technique, mentioned in a previous paper by the authors. Comparison of experimental results to simulation using a half-space dyadic Green’s function in the frequency domain requires development of transfer functions to transform the experimental data into a compatible form. A channel transfer function (CTF) was developed to avoid having to model the transmitting and receiving characteristics of the antennas. The CTF considers electromagnetic wave propagation through the intervening media only (soil in this case) and hence …

Cross-Well Radar. I: Experimental Simulation Of Cross-Well Tomography And Validation, Arvin Farid, Akram N. Alshawabkeh, Carey M. Rappaport

Carey Rappaport

This paper explains and evaluates the potential and limitations of conducting cross-well radar (CWR) in sandy soils. Implementing the experiment and data collection in the absence of any scattering object, and in the presence of an acrylic plate [a representative of dielectric objects, such as dense nonaqueous phase liquid (DNAPL) pools, etc.], as a contrasting object in a water-saturated soil is also studied. To be able to image the signature of any object, more than one pair of receiving and transmitting antennas are required. The paper describes a method to achieve repeatable, reliable, and reproducible laboratory results for different transmitter-receiver …

Experimental Validation Of A Numerical Forward Model For Tunnel Detection Using Cross-Borehole Radar, Arvin Farid, Jose A. Martinez-Lorenzo, Akram N. Alshawabkeh, Carey M. Rappaport

Carey Rappaport

The goal of this research is to develop an experimentally validated two-dimensional(2D) finite difference frequency domain (FDFD) numerical forward model to studythe potential of radar-based tunnel detection. Tunnel detection has become a subject of interest to the nation due to the use of tunnels by illegal immigrants, smugglers, prisoners, assailants, and terrorists. These concerns call for research to nondestructively detect, localize, and monitor tunnels. Nondestructive detection requires robust image reconstruction and inverse models, which in turn need robust forward models. Cross-Well Radar (CWR) modality is used for experimentation to avoid soil-air interface roughness. CWR is not a versatile field technology …

Electromagnetic Waves In Contaminated Soils, Arvin Farid, Akram N. Alshawabkeh, Carey M. Rappaport

Carey Rappaport

No abstract provided.