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Assessment of the Potential Role of Blizzard Damage in the Spatial Distribution of Southern Pine Beetle Infestation in Unicoi County, Tennessee.Jennings, David Scott 04 May 2002 (has links)
The Southern Pine Beetle, or SPB, (Dendroctonus frontalis Zimmerman) is a bark beetle that is endemic to the Southern forest ecosystem. Beetle populations remain stable for years at a time; however, for reasons not fully understood the beetle undergoes accelerated population growth on approximate ten-year cycles, culminating in increased beetle activity. Although most trees can withstand a beetle assault when populations are reduced, healthy trees, and even pine species that are not generally attacked can become a host tree for millions of beetles during infestations.
Much of Appalachia was paralyzed by an unusually heavy snowstorm on January 27, 1998, resulting in major power failures and tremendous tree damage. Environmental hazards such as this storm have historically been a factor with southern pine beetle populations. This study hypothesizes that the blizzard of January 27, 1998, significantly increased the southern pine beetle population. The evidence, however, did not support this hypothesis.
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Spatial Analysis of Urbanization in the Salt Lake Valley: An Urban Ecosystem PerspectiveLowry, John H., Jr. 01 May 2010 (has links)
Because urban areas comprise a variety of biotic (e.g. people, trees) and abiotic (e.g. streets, water) components that interact and are often interdependent upon one another, it is helpful to study urban areas as urban ecosystems. Our goal in Chapter 2 is to measure and quantify the spatial and demographic structure of the urbanized portion of Salt Lake County, Utah. We use 18 metrics from four broad categories (density, centrality, accessibility, and neighborhood mix) to measure urban form for three age-based residential neighborhood types. Using analysis of variance (ANOVA) we test for differences in mean values for the 18 urban form metrics. We find measureable differences in the spatial and demographic characteristics of these neighborhoods, suggesting that the rate of urban sprawl in Salt Lake County has been holding steady, if not increasing, during the last 20 years. Chapter 3 seeks to better understand how spatial heterogeneity in urban tree canopy is related to household characteristics, urban form, and the geophysical landscape of residential neighborhoods. We consider neighborhood age a factor that moderates the relationship between these determinants of tree canopy, and the abundance of tree canopy observed. Using linear regression analysis with neighborhood age as interaction term, we assess the relationship between tree canopy and 15 determinants of tree canopy abundance at three neighborhood ages. We find that neighborhood age has a significant moderating effect on the relationship between several determinants of canopy cover and the abundance of canopy cover observed. While the urban forest provides many benefits to human well-being, it also consumes considerable quantities of water. An important question in Chapter 4 is to determine whether a growing urban forest increases overall residential irrigation demand, decreases demand, or has no apparent effect. Using a water demand model borrowed from agronomy, we estimate irrigation water demand based on the area of three residential landscape types and climatic factors. We project future residential water demand by generating residential landscape scenarios based on predicted urban forest canopy growth. We find that urban forest growth has the effect of stabilizing or potentially decreasing overall residential irrigation water demand.
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Investigating the Influence of Esri Story Map Design on Partcipation in Sustainability-Related ActivitiesAustin, Brittany Grace 01 April 2018 (has links)
Decades of scientific inquiry have conveyed evidence in support of sustainability efforts to mitigate some of the greatest challenges and dilemmas facing modern and future societies. The solutions to these dilemmas may not be achievable in the short-term, yet, through increased public participation in sustainable community development, smallscale, localized solutions can be obtained. This preliminary research explored the influence of Environmental Systems Research Institute (Esri) story map designs on participation in sustainability-related activities among individuals who expressed interest in sustainable lifestyles. Specifically, this exploratory study was designed to demonstrate the applicability of interactive web geographic information systems (GIS) applications as platforms for promoting experiential learning and improved public participation in targeted sustainability-related activities. Web GIS applications were produced using multiple Esri story map design templates to visualize the sustainability-related features (e.g., Farms & Food, Shops & Services, Groups) of Skagit County, Washington; Barron County, Wisconsin; and Warren County, Kentucky. Story map applications were distributed electronically in the study site locations using social media, email disbursement, and website placement. After viewing the story map, research participants completed a survey regarding their preferences among the story map designs and their current participation in sustainability initiatives or activities. Completed surveys from 104 respondents were analyzed to begin to better understand participant opinions of the story map designs and the influences of these designs on participation in sustainability related activities. While more survey data are needed to understand fully the influence of story maps on participation in sustainability-related activities, participants in this study indicated that story map applications can increase accessibility to sustainability-related information and enhance the likelihood of participation in future sustainability-related activities. Of the four story map designs evaluated as part of this exploratory study, the data suggest the shortlist design may be the best suited to inform and encourage participation in sustainability-related activities.
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Assessing PPGIS Usability and its Relationship to Spatial Data Production: a Case StudyHitchins, Timothy Michael 12 September 2018 (has links)
Modern Geoweb-enabled PPGIS methodologies incorporate interactive map applications as the main driver for public engagement and data collection. However, little research explores exactly how the public interact with these applications to produce spatial data, a fact that contributes to criticisms of final data quality. Usability evaluation offers a solution for developing better PPGIS data production systems by identifying problems in the application interface for which the public engage. Drawing on a case study example of a PPGIS application developed to collect socio-spatial data from members of a random public, this paper addresses usability in a three-stage approach. First, controlled experimentation methods capture performance, preference, and data production metrics. Second, visual and statistical analysis of the captured usability data identify problems in the interface. Results indicate that users learned, became efficient, and were generally satisfied with the application, but also committed errors that may have affected data quality. Third, a solution-oriented critique of the application interface suggests new design options to mitigate future problems in similar applications. The paper ends by providing a conceptual framework for usability as it relates to PPGIS data production and incorporates it into an informed discussion on data quality and future research needs for maintaining the viability of PPGIS projects.
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GIS Spatial Analysis of Arctic Settlement Patterns: A Case Study in Northwest AlaskaJunge, Justin Andrew 05 September 2017 (has links)
In northwest Alaska, archaeologists hypothesize that environmental variability was a major factor in both growing coastal population density, with large aggregated villages and large houses, between 1000 and 500 years ago (ya), and subsequent decreasing population density between 500 ya and the contact era. After 500 ya people are thought to have dispersed to smaller settlements with smaller house sizes in coastal areas, and perhaps, upriver. This settlement pattern was identified through research at four site locations over 30 years ago. The changing geographic distribution of sites, associated settlement size, and house size has not been examined in detail. A more careful examination of changing northwest Alaskan settlement patterns is needed before larger questions about socio-economic organization can be addressed. I use Geographic Information Systems (GIS) to evaluate the evidence for a geographic redistribution of Arctic peoples during the Late Holocene.
The author constructed a database of settlement location and site attribute information, specifically the number of houses within each settlement and the size (m2). Data were collected from a dataset of Western Arctic National Parklands (WEAR), the Alaska Heritage Resource Survey (AHRS) database of archaeological sites in Alaska, 409 unpublished site reports and field notes curated by the National Park Service (NPS) and Bureau of Indian Affairs (BIA), and the results of recent fieldwork in northwest Alaska. A total of 486 settlements were identified within the northwest Alaska with 128 settlements having temporal and site attribute data.
The author incorporated settlement size data into a GIS database and then carried out global, Moran's I, local Moran's I, and local Getis-Ord spatial analyses to test whether settlement redistribution occurred and if key settlement locations shifted after 500 ya. The site attribute data (number of houses and average size of houses) are used to test the additional aspects of the proposed settlement pattern change after 500 ya. A total of 83 settlements with 465 houses are used to test if the average size of settlements and average house size changed after 500 ya.
The results of the spatial analyses indicate no statistically significant patterns in the spatial distribution of settlements. Site attribute analysis shows no statistical difference in the average number of houses per village or the average size of houses before or after 500 ya. The results of this work build our understanding of regional settlement patterns during the late Holocene. By testing settlement pattern change, i.e. settlement distribution, settlement size, and house size, future research into settlement pattern change can begin to evaluate likely causes for the observed changes. My method, specifically the use of GIS as a method for testing settlement pattern change, can be applied to other regions and temporal scales.
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Flood risk analysis for the Iowa Statewide Floodplain Mapping ProjectReith, Benjamin Samuel 01 December 2012 (has links)
Flooding is a major hazard in the Midwest, accounting for more economic damage than any other hazard. Recent major flooding events in Iowa have created a greater need for the monitoring of floodplain areas. The objective of this paper is to evaluate flood risk through the synthesis of geospatial data with flood maps for thirteen Hydrologic Unit Codes (HUC 8s) in southwest Iowa. Using ArcGIS, exposure of ecosystem services, population, and environmental hazards can be located within the 10, 50, 100, 500 year floodplains. Additionally, the effectiveness of hydric soils as a floodplain proxy is evaluated using SSURGO soil data. An overview of FEMA HAZUS-MH 2.0 flood loss estimation software is provided and a model of the East Nishnabotna HUC 8 is evaluated. An alternative economic loss framework based on an NED land use raster and structure data is compared for the region. This study aims to provide beneficial floodplain information for development and regulation decisions.
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Evaluation of Synthetic Unit Hydrograph Techniques For Utah Probable Maximum Flood DeterminationsShammet, Ashraf Mohammed 01 May 1995 (has links)
Every dam must be capable of safely passing a predetermined flood magnitude. For high-hazard dams, it is a common practice to require that this flood be the Probable Maximum Flood (PMF). The determination of the PMF starts with the determination of the Probable Maximum Precipitation (PMP). We used the generalized estimates of the PMP as outlined in Hydrometeorological Report (HMR) 49. In this study we used the storm event model approach to convert the PMP into PMF. Different synthetic unit hydrograph (SUH) techniques were then used in the conversion process. The Soil Conservation Service (SCS) curve number method was used to estimate the losses, and the U.S. Bureau of Reclamation (USBR) lag time relationship was used as the basis for estimating the time parameters for the different (SUH) methods.
The objectives of this study were 1) to evaluate the theoretical and empirical basis for the SUH methods that are commonly used for Utah PMF determinations; 2) to compare the PMF determinations for representative Utah watersheds based on alternative SUH methods using Geographic Information System (GIS) techniques, and to explore the effects of parameter uncertainty ; and 3) to make recommendations for the selection and use of SUH methods for Utah PMF determinations.
An interactive PMF modeling system was formulated. The modeling system processes the different databases and estimates the parameters required for HEC 1 model input to produce the PMF hydrograph. Five SUHs were used, tbe SCS, Clark, Snyder, USBR, and the Corps of Engineers (COE) LA valley S-graph. Seven representative Utah high-hazard dam sites were selected and used in the evaluation of the five SUH techniques, focusing on their procedure, practice and applicability, and analytical and empirical evaluations.
GIS procedures proved to be a very efficient and flexible means for obtaining rainfall-runoff model inputs. Deviation of the site-specific time-area curve from the default curve in HEC 1 leads to errors in the peak flow estimate. In the absence of suitable events for site-specific development of unit hydrographs, the USBR SUH technique is to be used, but careful consideration should be given to the appropriateness of the use of local storm K, values for Utah local storm PMFs.
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GIS model for assessment of land use and urban development effects on stormwater runoff: Puhinui Catchment case studyKrpo, Ana Unknown Date (has links)
As local authorities are becoming more interested in the assessment of pollutant loads, this study offers a Geographic Information System (GIS) model for assessing nonpoint source of pollution for two scenarios: the current and ultimate stage of urbanization. The Puhinui Catchment, Manukau City, has been used as a case study in developing and testing this model. This catchment has all the attributes of a "typical" urban area and gives a good representation of the effects of land use on the receiving waters of Puhinui Stream and its estuary. Annual mass contaminant loadings were calculated by firstly assessing the physical characteristics of the Puhinui catchment (case study catchment) and secondly describing the nature of storm water quality and calculating the annual mass contaminant loadings.GIS is used to multiply the annual runoff volume by a mean pollutant concentration to acquire an average annual pollutant load. The annual runoff volume is calculated from the drainage area, runoff coefficient and annual rainfall. To calculate the total mean pollutant load, the pollutant loads for all land use types within the catchment are summed and the process is applied for each pollutant. This GIS model determines the connection of typical pollutant concentrations with land uses in the catchment and offers a characterisation of nonpoint source pollution in that catchment. This model can be used for, identifying catchment areas that contribute considerably to the pollution of waterways, determining the appropriate treatment of the storm water runoff for particular sub catchment, storm water quality improvement prioritization and cost-benefit analysis, selecting locations for water-quality monitoring stations, improvement in maintenance practices, assessment of proposed development environmental effects.
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Spatial information sharing for better regional decision makingWeyman, Tamara R., University of Western Sydney, College of Health and Science, School of Natural Sciences January 2007 (has links)
The overall aim of this research project was to determine whether a technological spatial innovation, such as online spatial portal (OSP), would provide an effective mechanism to support better policy dialogue between the technical capacity and decision making spheres within and between local government, enabling improved policy development and application. This was addressed by using a qualitative, multi-methodological research methodology to examine both current theory and the practical experiences and opinions of local government professionals. The literature review focused on the emerging theory field of ‘policy dialogue’ - the local governance and the importance of spatial information (SI) and geographic information systems (GIS) for supporting decisions. The interview analysis of sample Greater Western Sydney (GWS) council professionals confirmed the complexity of local government policy. A significant issue that hindered policy development across the participating local governments was the occurrence of silo cultures within internal and external relationships between council officers. The second interview phase with GWS council professionals, followed by a demonstration of an OSP concept (GWSspatial), identified the applications, opportunities and challenges for the development and use of a technological spatial innovation. The key applications identified were- sharing and knowledge management of SI, immediate management of SI, immediate online access and integration of local/regional SI, and analysis opportunities to facilitate purposeful dialogue and informed decision making by council professionals within a region. Policy framework case studies were conducted at three scales: the Pitt Town development – at LGA level; Bushfire emergency management – at cross jurisdictional level; and the Sydney Metropolitan Strategy - at regional level. The catalysts, which trigger the need, acceptance and commitment of decision makers, thereby supporting the key applications of a technological spatial innovation include disaster response, critical environment management challenges and regional land use planning and management. / Doctor of Philosophy (PhD)
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The integration of GPS and GIS in transportation applicationsZito, Rocco January 2002 (has links)
No description available.
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