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State-of-the-Art for Assessing Earthquake Hazards in the United States: Report 11, Imagery in Earthquake Analysis

Description: Partial abstract: "Recent advances in the fields of remote sensing, engineering geology, seismology, and earthquake engineering have developed a need for a systematic comprehensive review of the basic principles and methods of applying remote sensing for evaluation of earthquake hazards and seismic risk. This paper responds to this need by reviewing basic concepts, summarizing essential, state-of-the-art knowledge of theory and instrumental methods, establishing procedures evaluations, and discussing representative case histories that illustrate earthquake hazard evaluations that are based on remote sensing analysis."
Date: December 1978
Creator: Glass, Charles E. & Slemmons, David B.
Partner: UNT Libraries Government Documents Department

The Influence of Urban Green Spaces on Declining Bumble Bees (Hymenoptera: Apidae)

Description: Bumble bees (Bombus spp.) are adept pollinators of countless cultivated and wild flowering plants, but many species have experienced declines in recent decades. Though urban sprawl has been implicated as a driving force of such losses, urban green spaces hold the potential to serve as habitat islands for bumble bees. As human populations continue to grow and metropolitan areas become larger, the survival of many bumble bee species will hinge on the identification and implementation of appropriate conservation measures at regional and finer scales. North Texas is home to some the fastest-growing urban areas in the country, including Denton County, as well as at least two declining bumble bee species (B. pensylvanicus and B. fraternus). Using a combination of field , molevular DNA and GIS methods I evaluated the persistence of historic bumble bee species in Denton County, and investigated the genetic structure and connectivity of the populations in these spaces. Field sampling resulted in the discovery of both B. pensylvanicus and B. fraternus in Denton County's urban green spaces. While the relative abundance of B. fraternus in these spaces was significantly lower than historic levels gleaned from museum recors, that of B. pensylvanicus was significantly higher. Statistical analyses found that both bare ground and tree cover surrounding sample sites were negatively associated with numbers of bumble bee individuals and hives detected in these green spaces. Additionally, limited genetic structuring of bumble bee populations was detected, leading to the conclusion that extensive gene flow is occurring across populations in Denton County.
Date: May 2016
Creator: Beckham, Jessica Lorene
Partner: UNT Libraries

Prioritizing Riparian Cooridors for Water Quality Protection in Urbanizing Watersheds

Description: This article describes the design of a GIS and remote sensing based analysis tool called the Water Quality Corridor Management model to identify and prioritize highly functioning riparian ecosystems for the preservation of steam corridor conditions.
Date: May 21, 2010
Creator: Atkinson, Samuel F.; Hunter, Bruce & English, April
Partner: UNT College of Arts and Sciences

Use of Satellite Imagery and GIS to Model Brood-Rearing Habitat for Rio Grande Wild Turkey Populations Occurring in the Western Cross Timbers Region of Texas

Description: Remote sensing and GIS have become standard tools for evaluating spatial components of wildlife habitats. These techniques were implemented to evaluate Rio Grande wild turkey (Meleagris gallopavo) poult-rearing habitat in the Western Cross Timbers region of Texas. Texas Parks and Wildlife (TPWD) random roving turkey counts for 1987-1989 and 1998-2000 were selected, indicating locations where hens with poults were observed. Satellite imagery from 1988 and 1999 was classified and then processed with Patch Analyst. To add robustness, stream, road and census population densities were also evaluated for each turkey location. Analysis of the 1988 canopy cover image, comparing observed locations with randomly-selected habitat cells (N = 20) indicated significant differences (p <.05) for patch edge variables. Mean patch edge was significantly greater for habitat locations where hens with poults were observed than for those selected at random. Spatial data for 1999 did not indicate a significant difference (p < .05) between sampling groups (observed vs. random, N = 30). Significant differences (p <.05) did occur for turkey locations observed in both 1988 and 1999 (N = 7). This demonstrates the adaptability of wild turkey hens, as habitats change over time, hens continued to visit the same locations even though the habitat had significantly changed for select spatial variables.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: August 2002
Creator: Miller, Christopher J.
Partner: UNT Libraries

Use of GIS and Remote Sensing Technologies to Study Habitat Requirements of Ocelots, Leopardus pardalis, in south Texas

Description: The goals of this study were to use Geographic Information Systems (GIS) and remote sensing technologies to gain a better understanding of habitat requirements of a population of ocelots in south Texas, and then apply this knowledge to form a predictive model to locate areas of suitable habitat in Willacy and Cameron counties, Texas. Satellite imagery from August 1991 and August 2000 were classified into four land cover types: closed canopy, open canopy, water, and urban/barren. These classified images were converted into digital thematic maps for use in resource utilization studies and modeling. Location estimates (762 from 1991 and 406 from 2000) were entered into a GIS in order to extract information about home range and resource selection. Each animal's home range was calculated using both Minimum Convex Polygon (MCP) and Kernel home range estimators (95% and 50%). Habitat parameters of interest were: soil, land cover, human density, road density, and distance to closest road, city and water body. Ocelots were found to prefer closed canopy and avoid open canopy land cover types. Ocelots preferred soils known to support thorn scrub, an indication of the importance of this habitat. Landscape metrics associated with habitat used by ocelots were determined through the use of Patch Analyst, an extension for ArcView 3.2. Contrary to expectations, ocelots utilized areas with greater fragmentation than random areas available for use. However, this use of highly fragmented areas was an indication of the degree of fragmentation of suitable habitat in the area. Further investigation of patch size selection indicated that ocelots used large sized patches disproportionately to availability, indicating a preference for larger patches. A model was created using the resource selection and habitat preference GIS database from 1991. This model was used to identify areas of “optimal”, ”sub-optimal”, and “unsuitable” habitat for ocelots in 2000. ...
Date: August 2002
Creator: Jackson, Victoria L.
Partner: UNT Libraries

Archeological Testing at Fort St. Leon, Plaquemines Parish, Louisiana

Description: This report describes archaeological testing at a site known as Fort St. Leon in Louisiana. Studies were made of levee building, geomorphology, and comparison of archival maps and aerial photographs, which contribute to the understanding of human activity as well as geological processes at the site.
Date: May 1983
Creator: Gilmore, Kathleen & Noble, Vergil
Partner: UNT Institute of Applied Sciences

Capability and cost assessment of the major forest nations to measure and monitor their forest carbon

Description: According to the Executive Summary, the aims and objective of this report are to provide an assessment of national capacity and capability in 25 tropical countries for measuring and monitoring forest as a requirement for reporting on REDD under IPCC guidelines. This paper was commissioned by the United Kingdom Office of Climate Change as background work to its report 'Climate Change: Financing Global Forests' (the Eliasch Review).
Date: April 7, 2008
Creator: Harcastle, P. D.; Baird, David & Harden, Virginia
Partner: UNT Libraries

Comparison of IKONOS Derived Vegetation Index and LiDAR Derived Canopy Height Model for Grassland Management.

Description: Forest encroachment is understood to be the main reason for prairie grassland decline across the United States. In Texas and Oklahoma, juniper has been highlighted as particularly opportunistic. This study assesses the usefulness of three remote sensing techniques to aid in locating the areas of juniper encroachment for the LBJ Grasslands in Decatur, Texas. An object based classification was performed in eCognition and final accuracy assessments placed the overall accuracy at 94%, a significant improvement over traditional pixel based methods. Image biomass was estimated using normalized difference vegetation index (NDVI) for 1 meter resolution IKONOS winter images. A high correlation between the sum of NDVI for tree objects and field tree biomass was determined where R = 0.72, suggesting NDVI sum of a tree area is plausible. However, issues with NDVI saturation and regression produced unrealistically high biomass estimates for large NDVI. Canopy height model (CHM) derived from 3-5m LiDAR data did not perform as well. LiDAR typically used for digital elevation model (DEM) production was acquired for the CHM and produced correlations of R = 0.26. This suggests an inability for this particular dataset to identify juniper trees. When points that registered a tree height where correlated with field values, an R = 0.5 was found, suggesting denser point spacing would be necessary for this type of LiDAR data. Further refining of the methods used in this study could yield such information as the amount of juniper tree for a given location, fuel loads for prescribed burns and better information for the best approach to remove the juniper and ultimately management juniper encroachment into grasslands.
Date: December 2009
Creator: Parker, Gary
Partner: UNT Libraries

Integrated Land Ecosystem-Atmosphere Processes Study: Science Plan and Implementation Strategy

Description: The iLEAPS Science Plan and Implementation Strategy defines the scientific objectives and key research issues of the land-atmosphere project of the International Geosphere-Biosphere Programme. It also outlines a strategy for addressing the key research questions. The scope of iLEAPS research spans from molecular level processes - such as synthesis of volatile organic compounds in vegetation - to Earth System science issues, climate and global change. iLEAPS research emphasises the importance of connections, feedbacks and teleconnections between the numerous processes in the land-atmosphere interface. Due to the complexity and wide range of scientific issues, iLEAPS stresses the need for increased integrative approaches and collaboration, involving scientists from various disciplines, experimentalists and modellers, and international research projects and programmes.
Date: 2005
Creator: Integrated Land Ecosystem-Atmosphere Processes Study
Partner: UNT Libraries

Global Wetland Distribution and Functional Characterization: Trace Gases and the Hydrologic Cycle

Description: The IGBP Wetlands workshop (Santa Barbara, CA, USA,16-20 May 1996) was held for the purpose of identifying data and research needs for characterizing wetlands in terms of their role in biogeochemical and hydrologic cycles. Wetlands cover only about 1% of the Earth's surface, yet are responsible for a much greater proportion of biogeochemical fluxes between the land surface, the atmosphere and hydrologic systems. They play a particularly important function in processing methane, carbon dioxide, nitrogen, and sulphur as well as in sequestering carbon. Considerable progress has been made in the past 10 years regarding wetlands and methane: a global digital dataset of wetlands (Matthews and Fung 1987) was produced and global observations of methane have been combined with global three-dimensional atmospheric modelling (Fung et al. 1991) to constrain modelled fluxes of methane from high-latitude wetlands. Furthermore, significant advances have been made in understanding the biogeochemical processes that control fluxes of methane and other trace gases. The progress has made clear that present wetland classification schemes do not accurately reflect their roles in these processes because they have been based on wetland attributes such as dominant plant types which do not reflect differences in the functions of wetlands regarding biogeochemical cycles. Further, traditional wetland classifications cannot be distinguished on the basis of global remotely sensed observations. Consequently, it has been impossible to accurately quantify the distribution of key fluxes on the basis of observed land cover. The workshop developed a wetland parameterization scheme based on observable quantities to better incorporate wetlands into global land surface characterization schemes so that the relation between land cover and biogeochemical fluxes can be more accurately determined. An improved understanding of this relation will make it possible to better use observed or historical changes in land cover to infer changes in biogeochemical fluxes, including the cycles ...
Date: 1998
Creator: Sahagian, Dork & Melack, John
Partner: UNT Libraries

On-Road Remote Sensing of Motor Vehicle Emissions: Associations between Exhaust Pollutant Levels and Vehicle Parameters for Arizona, California, Colorado, Illinois, Texas, and Utah

Description: On-road remote sensing has the ability to operate in real-time, and under real world conditions, making it an ideal candidate for detecting gross polluters on major freeways and thoroughfares. In this study, remote sensing was employed to detect carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxide (NO). On-road remote sensing data taken from measurements performed in six states, (Arizona, California, Colorado, Illinois, Texas, and Utah) were cleaned and analyzed. Data mining and exploration were first undertaken in order to search for relationships among variables such as make, year, engine type, vehicle weight, and location. Descriptive statistics were obtained for the three pollutants of interest. The data were found to have non-normal distributions. Applied transformations were ineffective, and nonparametric tests were applied. Due to the extremely large sample size of the dataset (508,617 records), nonparametric tests resulted in "p" values that demonstrated "significance." The general linear model was selected due to its ability to handle data with non-normal distributions. The general linear model was run on each pollutant with output producing descriptive statistics, profile plots, between-subjects effects, and estimated marginal means. Due to insufficient data within certain cells, results were not obtained for gross vehicle weight and engine type. The "year" variable was not directly analyzed in the GLM because "year" was employed in a weighted least squares transformation. "Year" was found to be a source of heteroscedasticity; and therefore, the basis of a least-squares transformation. Grouped-years were analyzed using medians, and the results were displayed graphically. Based on the GLM results and descriptives, Japanese vehicles typically had the lowest CO, HC, and NO emissions, while American vehicles ranked high for the three. Illinois, ranked lowest for CO, while Texas ranked highest. Illinois and Colorado were lowest for HC emissions, while Utah and California were highest. For NO, Colorado ranked highest ...
Access: This item is restricted to the UNT Community Members at a UNT Libraries Location.
Date: May 2003
Creator: Dohanich, Francis Albert
Partner: UNT Libraries

Habitat Fragmentation by Land-Use Change: One-Horned Rhinoceros in Nepal and Red-Cockaded Woodpecker in Texas

Description: This research focuses on the spatial analysis of the habitat of two vulnerable species, the one-horn rhinoceros in the grasslands of southern Nepal, and the red-cockaded woodpecker in the Piney woods of southeast Texas, in the USA. A study sites relevant for biodiversity conservation was selected in each country: Chitwan National Park in Nepal, and areas near the Big Thicket National Preserve in Texas. Land-use differs in the two study areas: the first is still undergoing agrarian development while the second is in a technological phase and undergoing urbanization processes. Satellite remote sensing images were used to derive land-cover maps by supervised classification. These maps were then processed by Geographic Information Systems methods to apply habitat models based on basic resources (food and cover) and obtain habitat suitability maps. Several landscape metrics were computed to quantify the habitat characteristics especially the composition and configuration of suitable habitat patches. Sensitivity analyses were performed as the nominal values of some of the model parameters were arbitrary. Development potential probability models were used to hypothesize changes in land-use of the second study site. Various scenarios were employed to examine the impact of development on the habitat of red-cockaded woodpecker. The method derived in this study would prove beneficial to guide management and conservation of wildlife habitats.
Date: December 2010
Creator: Thapa, Vivek
Partner: UNT Libraries

Thermal Identification of Clandestine Burials: A Signature Analysis and Image Classification Approach

Description: Clandestine burials, the interred human remains of forensic interest, are generally small features located in isolated environments. Typical ground searches can be both time-consuming and dangerous. Thermal remote sensing has been recognized for some time as a possible search strategy for such burials that are in relatively open areas; however, there is a paucity of published research with respect to this application. This project involved image manipulation, the analyses of signatures for "graves" of various depths when compared to an undisturbed background, and the use of image classification techniques to tease out these features. This research demonstrates a relationship between the depth of burial disturbance and the resultant signature. Further, image classification techniques, especially object-oriented algorithms, can be successfully applied to single band thermal imagery. These findings may ultimately decrease burial search times for law enforcement and increase the likelihood of locating clandestine graves.
Date: December 2010
Creator: Servello, John A.
Partner: UNT Libraries

Applications of Remote Sensing and GIS to Modeling Fire for Vegetative Restoration in Northern Arizona

Description: An accurate fire model is a useful tool in predicting the behavior of a prescribed fire. Simulation of fire requires an extensive amount of data and can be accomplished best using GIS applications. This paper demonstrates integrative procedures of using of ArcGIS™, ERDAS Imagine™, GPS, and FARSITE© to predict prescribed fire behavior on the Kaibab-Paiute Reservation. ArcGIS was used to create a database incorporating all variables into a common spatial reference system and format for the FARSITE model. ArcGIS Spatial Analyst was then used to select optimal burn sites for simulation. Our predictions will be implemented in future interagency efforts towards vegetative restoration on the reservation.
Date: August 2003
Creator: Hardison, Tanya
Partner: UNT Libraries

Analysis of the One-Horned Rhinoceros (Rhinoceros Unicornis) Habitat in the Royal Chitwan National Park, Nepal.

Description: This study analyzes the remaining suitable habitat of the one-horned rhinoceros, Rhinoceros unicornis, in Royal Chitwan National Park of Nepal. An April 2003 Landsat image was classified into eight land cover types: wetland, sand, water, mixed forest, sal forest, agriculture, settlement, and grassland. This image was converted into habitat suitability maps using cover, food, and water. The rhinoceros prefers grassland habitat with oxbow lakes and closed canopy during the monsoon season. Nominal values of five parameters were used to create a map of habitat suitability index. The map was categorized into four habitat classes: highly unsuitable, unsuitable, moderately suitable habitat, and suitable. Landscape metrics, patch metrics and class metrics associated with habitat were determined through the use of FRAGSTATS.
Date: December 2005
Creator: Thapa, Vivek
Partner: UNT Libraries

Quantifying Forest Vertical Structure to Determine Bird Habitat Quality in the Greenbelt Corridor, Denton, Tx

Description: This study presents the integration of light detection and range (LiDAR) and hyperspectral remote sensing to create a three-dimensional bird habitat map in the Greenbelt Corridor of the Elm Fork of the Trinity River. This map permits to examine the relationship between forest stand structure, landscape heterogeneity, and bird community composition. A biannual bird census was conducted at this site during the breeding seasons of 2009 and 2010. Census data combined with the three-dimensional map suggest that local breeding bird abundance, community structure, and spatial distribution patterns are highly influenced by vertical heterogeneity of vegetation surface. For local breeding birds, vertical heterogeneity of canopy surface within stands, connectivity to adjacent forest patches, largest forest patch index, and habitat (vegetation) types proved to be the most influential factors to determine bird community assemblages. Results also highlight the critical role of secondary forests to increase functional connectivity of forest patches. Overall, three-dimensional habitat descriptions derived from integrated LiDAR and hyperspectral data serve as a powerful bird conservation tool that shows how the distribution of bird species relates to forest composition and structure at various scales.
Date: August 2013
Creator: Matsubayashi, Shiho
Partner: UNT Libraries

A Storm Water Runoff Investigation Using Gis and Remote Sensing

Description: Environmental controls are becoming more and more expensive to implement, so environmental management is becoming more technologically advanced and efficient through the adoption of new techniques and models. This paper reviews the potential for storm water runoff for the city of Denton, Texas and with the main objective to perform storm water runoff analyses for three different land use datasets; each landuse dataset created with a different methodology. Also analyzed was the difference between two North Central Texas Council of Governments land use datasets and my own land use dataset as a part of evaluating new and emerging remote sensing techniques. The results showed that new remote sensing techniques can help to continually monitor changes within watersheds by providing more accurate data.
Date: August 2012
Creator: Jennings, Laura
Partner: UNT Libraries

Modelling land use change and nonpoint source pollution potential using remote sensing and geographic information system technology

Description: In this study Geographic Information System (GIS) technology was integrated with remote sensing techniques in order to determine the potential for nonpoint source pollution in the Lake Palestine and Cedar Creek Reservoir watersheds of North Central Texas. The Universal Soil Loss Equation was used to determine soil erosion potential from the watersheds, and export coefficients were used to estimate nutrient loadings into the reservoirs.
Date: August 1990
Creator: Walker, Scott William
Partner: UNT Libraries

A comparison of universal soil loss equation results using a remote sensing/GIS technique to results obtained using a field survey technique

Description: Digital satellite remote sensing and Geographic Information Systems (GIS) have been used in conjunction with the Universal Soil Loss Equation (USLE) to model soil erosion potential within watersheds. This study compared erosion estimates calculated by the remote sensing method to results obtained in the field by soil conservationists using conventional methods.
Date: December 1990
Creator: Hunter, Bruce Allan
Partner: UNT Libraries

Estimating nonpoint source pollution in north Texas watersheds through remote sensing and geographic information systems

Description: Monitoring nonpoint source pollution in a large area is often impractical. However, estimating nonpoint pollution through use of empirical models such as the Universal Soil Loss Equation (USLE) provides a basis for identifying problem areas, and setting management priorities. The purpose of this study was to determine the feasibility of using Landsat imagery and existing geographic data to estimate the effects of land use changes on water quality in four North Texas watersheds over a twelve year period.
Date: December 1989
Creator: Groome, Kristina M. (Kristina Martin)
Partner: UNT Libraries

Preliminary Applications of Landsat Images and Aerial Photography for Determining Land-Use, Geologic, and Hydrologic Characteristics--Yampa River Basin, Colorado and Wyoming

Description: From abstract: "This study used Landsat images and small-scale color and color-infrared photographs for selected geologic, hydrologic, and land-use applications within the Yampa River Basin" in Colorado and Wyoming. It includes maps, tables, and a glossary.
Date: October 1978
Creator: Heimes, Frederick J.; Moore, Gerald K. & Steele, Timothy Doak
Partner: UNT Libraries Government Documents Department

Application of Thermal Imagery and Aerial Photography to Hydrologic Studies of Karst Terrane in Missouri

Description: From abstract: Planning waste-disposal facilities and impoundments is complicated by karst carbonate terrane in the Ozarks. Thermal imagery (8-13 micrometer wavelength) and color infrared photography aid in identifying losing streams, sinkholes and hydrologic conditions encouraging collapse. Imagery and photography were acquired in Greene and Reynold Counties, Mo., in March 1972 and June 1973. Differences in thermal levels correlating with losing and gaining reaches of Logan Creek valley, Reynolds County, were not visually apparent in predawn March imagery but statistical analysis of predawn magnetic-tape data indicated greater variance in emitted energy from the losing reach than from the gaining reach.
Date: September 1977
Creator: Harvey, E. J.; Williams, J. H. & Dinkel, T. R.
Partner: UNT Libraries Government Documents Department

Ground-Water Resources of Chester County, Pennsylvania

Description: From purpose and scope: This report provides basic information on the ground-water resources of Chester County, Pennsylvania, which is an area of about 760 square miles (1970 meters) in southeastern Pennsylvania. It discusses the availability and quality of the water in the water-bearing units in the county and the relation of the ground water to surface water.
Date: September 1977
Creator: McGreevy, Laurence J. & Sloto, Ronald A.
Partner: UNT Libraries Government Documents Department

An Analysis of the Habitat of the Greater One-Horned Rhinoceros Rhinoceros Unicornis (Mammalia: Perissodactyla: Rhinocerotidae) at the Chitwan National Park, Nepal

Description: This article uses geographic information systems and landscape-level data obtained from remote sensing sources to build a habitat suitability index model for the Greater One-horned Rhinoceros.
Date: August 14, 2013
Creator: Thapa, Vivek; Acevedo, Miguel F. & Limbu, Kul P.
Partner: UNT College of Engineering