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Remote sensing

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Evaluation Of Soil As A Risk Indicator For Human Leptospirosis In Coastal, Rural Ecuador, Chad Allen Weddell Sep 2015

Evaluation Of Soil As A Risk Indicator For Human Leptospirosis In Coastal, Rural Ecuador, Chad Allen Weddell

USF Tampa Graduate Theses and Dissertations

Leptospirosis, a zoonotic disease caused by pathogenic spirochete bacteria (family Leptospiraceae, genus Leptospira), is endemic in developing tropical regions of the world. It occurs in epidemics and is endemic in Ecuador where environmental conditions are ideal for maintenance. The role of soil as a long term reservoir has been previously been documented. Geographic Information System (GIS) and Remote Sensing (RS) technology was used in our study to further explore the role of soil as an environmental reservoir and its potential use as a static risk indicator for disease. Red, Green, Blue (RGB) spectral band data from known leptospire …

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Remote Sensing Estimates Of Stand-Replacement Fires In Russia, 2002–2011, Alexander Krylov, Jessica L. Mccarty, Peter Potapov, Tatiana Loboda, Alexandra Tyukavina, Svetlana Turubanova, Matthew Hansen Oct 2014

Remote Sensing Estimates Of Stand-Replacement Fires In Russia, 2002–2011, Alexander Krylov, Jessica L. Mccarty, Peter Potapov, Tatiana Loboda, Alexandra Tyukavina, Svetlana Turubanova, Matthew Hansen

Michigan Tech Research Institute Publications

The presented study quantifies the proportion of stand-replacement fires in Russian forests through the integrated analysis of Landsat and Moderate Resolution Imaging Spectroradiometer (MODIS) data products. We employed 30 m Landsat Enhanced Thematic Mapper Plus derived tree canopy cover and decadal (2001–2012) forest cover loss (Hansen et al 2013 High-resolution global maps of 21st-century forest cover change Science 342 850–53) to identify forest extent and disturbance. These data were overlaid with 1 km MODIS active fire (earthdata.nasa.gov/data/near-real-time-data/firms) and 500 m regional burned area data (Loboda et al 2007 Regionally adaptable dNBR-based algorithm for burned area mapping from …

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Quantitative Analysis Of Woodpecker Habitat Using High-Resolution Airborne Lidar Estimates Of Forest Structure And Composition, James E. Garabedian, Robert Mcgaughey, Stephen E. Reutebuch, Bernard R. Parresol, John C. Kilgo, Christopher E. Moorman, M. Nils Peterson Jan 2014

Quantitative Analysis Of Woodpecker Habitat Using High-Resolution Airborne Lidar Estimates Of Forest Structure And Composition, James E. Garabedian, Robert Mcgaughey, Stephen E. Reutebuch, Bernard R. Parresol, John C. Kilgo, Christopher E. Moorman, M. Nils Peterson

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

Light detection and ranging (LiDAR) technology has the potential to radically alter theway researchers and managers collect data onwildlife–habitat relationships. To date, the technology has fostered several novel approaches to characterizing avian habitat, but has been limited by the lack of detailed LiDAR-habitat attributes relevant to species across a continuum of spatial grain sizes and habitat requirements. We demonstrate a novel three-step approach for using LiDAR data to evaluate habitat based on multiple habitat attributes and accounting for their influence at multiple grain sizes using federally endangered red-cockaded woodpecker (RCW; Picoides borealis) foraging habitat data fromthe Savannah River Site (SRS) …

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Assessing The Performance Of A Northern Gulf Of Mexico Tidal Model Using Satellite Imagery, Stephen C. Medeiros, Scott C. Hagen, Naira Chaouch, Jesse Feyen, Marouane Temimi, John F. Weishampel, Yuji Funakoshi, Reza Khanbilvardi Nov 2013

Assessing The Performance Of A Northern Gulf Of Mexico Tidal Model Using Satellite Imagery, Stephen C. Medeiros, Scott C. Hagen, Naira Chaouch, Jesse Feyen, Marouane Temimi, John F. Weishampel, Yuji Funakoshi, Reza Khanbilvardi

Publications and Research

Tidal harmonic analysis simulations along with simulations spanning four specific historical time periods in 2003 and 2004 were conducted to test the performance of a northern Gulf of Mexico tidal model. A recently developed method for detecting inundated areas based on integrated remotely sensed data (i.e., Radarsat-1, aerial imagery, LiDAR, Landsat 7 ETM+) was applied to assess the performance of the tidal model. The analysis demonstrates the applicability of the method and its agreement with traditional performance assessment techniques such as harmonic resynthesis and water level time series analysis. Based on the flooded/non-flooded coastal areas estimated by the integrated remotely …

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Ground-Truthing Maxent In East Texas Rivers, David F. Ford May 2013

Ground-Truthing Maxent In East Texas Rivers, David F. Ford

Biology Theses

Unionid mussels are a guild of freshwater, sedentary filter-feeders, which play a critical role in freshwater systems. Mussels are currently experiencing a global decline in both species richness and abundance, due to invasive species, human alteration of water systems, and climate change. In North America, which is considered to have the highest global diversity of bivalve species, native mussels are currently declining rapidly with at least 37 species considered to already be extinct. If extant mussel species are to be preserved, then it is vital that conservation efforts be prioritized towards areas in which they are likely to be found. …

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Low Mortality In Tall Tropical Trees, R. Q. Thomas, J. R. Kellner, D. B. Clark, D. R. Peart Apr 2013

Low Mortality In Tall Tropical Trees, R. Q. Thomas, J. R. Kellner, D. B. Clark, D. R. Peart

Dartmouth Scholarship

The dynamics of the tallest trees in tropical forests are of special interest due to their carbon content, canopy dominance, and the large canopy gaps created when they die. Known ecological mechanisms that may influence tall tree survival lead to conflicting predictions. Hydraulic stress and exposure to high winds and desiccation should increase death rates, yet the tallest trees have the greatest access to light and escape damage caused by falling boles and branches. The uncertainty in tall tree mortality rates has been difficult to address due to their low density, which makes mortality rates challenging to estimate accurately. Here, …

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Landscape Configuration And Urban Heat Island Effects: Assessing The Relationship Between Landscape Characteristics And Land Surface Temperature In Phoenix, Arizona, John Patrick Connors, Christopher S. Galletti, Winston T. L. Chow Feb 2013

Landscape Configuration And Urban Heat Island Effects: Assessing The Relationship Between Landscape Characteristics And Land Surface Temperature In Phoenix, Arizona, John Patrick Connors, Christopher S. Galletti, Winston T. L. Chow

Research Collection School of Social Sciences

The structure of urban environments is known to alter local climate, in part due to changes in land cover. A growing subset of research focuses specifically on the UHI in terms of land surface temperature by using data from remote sensing platforms. Past research has established a clear relationship between land surface temperature and the proportional area of land covers, but less research has specifically examined the effects of the spatial patterns of these covers. This research considers the rapidly growing City of Phoenix, Arizona in the United States. To better understand how landscape structure affects local climate, we explored …

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Hyperspectral Remote Sensing Of Water Quality In Lake Atitlan, Guatemala, Africa Ixmucane Flores Cordova Jan 2013

Hyperspectral Remote Sensing Of Water Quality In Lake Atitlan, Guatemala, Africa Ixmucane Flores Cordova

Theses

Lake Atitlan in Guatemala is a vital source of drinking water. The deteriorating conditions of water quality in this lake threaten human and ecological health as well as the local and national economy. Given the sporadic and limited measurements available, it is impossible to determine the changing conditions of water quality. The goal of this thesis is to use Hyperion satellite images to measure water quality parameters in Lake Atitlan. For this purpose in situ measurements and satellite-derived reflectance data were analyzed to generate an algorithm that estimated Chlorophyll concentrations. This research provides for the first time a quantitative application …

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A Survey Of Invasive Exotic Ants Found On Hawaiian Islands: Spatial Distributions And Patterns Of Association, Camie Frandsen Martin Dec 2012

A Survey Of Invasive Exotic Ants Found On Hawaiian Islands: Spatial Distributions And Patterns Of Association, Camie Frandsen Martin

Theses and Dissertations

An intensive sampling of all ant species encountered on 6 Hawaiian Islands: Big Island, Maui, Oahu, Kauai, Molokai, and Lanai took place between 1988 and 1996. Species presence and absence was recorded at each site. Using remote sensing, variables were added insitu and used throughout my analysis. Species accumulation curves suggest that sampling was comprehensive. There is a significant trend between island area and species richness which validates the Theory of Island Biogeography for invasive species. Islands were found to be significantly nested by area, order, and tourism. Cluster analysis shows a link between elevation, land-use and island, and species …

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Operational Meris-Based Nir-Red Algorithms For Estimating Chlorophyll-A Concentrations In Coastal Waters — The Azov Sea Case Study, Wesley J. Moses, Anatoly A. Gitelson, Sergey Berdnikov, Vladislav Saprygin, Vasily Povazhnyi Jan 2012

Operational Meris-Based Nir-Red Algorithms For Estimating Chlorophyll-A Concentrations In Coastal Waters — The Azov Sea Case Study, Wesley J. Moses, Anatoly A. Gitelson, Sergey Berdnikov, Vladislav Saprygin, Vasily Povazhnyi

School of Natural Resources: Faculty Publications

We present here results that strongly support the use of MERIS-based NIR-red algorithms as standard tools for estimating chlorophyll-a (chl-a) concentration in turbid productive waters. The study was carried out as one of the steps in testing the potential of the universal applicability of previously developed NIR-red algorithms, which were earlier calibrated using a limited set of MERIS imagery and in situ data from the Azov Sea and the Taganrog Bay, Russia, and data that were synthetically generated using a radiative transfer model. We used an extensive set of MERIS imagery and in situ data collected over …

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Nesting In The Clouds: Evaluating And Predicting Sea Turtle Nesting Beach Parameters From Lidar Data, Kristina H. Yamamoto Jan 2012

Nesting In The Clouds: Evaluating And Predicting Sea Turtle Nesting Beach Parameters From Lidar Data, Kristina H. Yamamoto

Electronic Theses and Dissertations

Humans' desire for knowledge regarding animal species and their interactions with the natural world have spurred centuries of studies. The relatively new development of remote sensing systems using satellite or aircraft-borne sensors has opened up a wide field of research, which unfortunately largely remains dependent on coarse-scale image spatial resolution, particularly for habitat modeling. For habitat-specialized species, such data may not be sufficient to successfully capture the nuances of their preferred areas. Of particular concern are those species for which topographic feature attributes are a main limiting factor for habitat use. Coarse spatial resolution data can smooth over details that …

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Linking Hydroperiod With Water Use And Nutrient Accumulation In Wetland Tree Islands, Xin Wang May 2011

Linking Hydroperiod With Water Use And Nutrient Accumulation In Wetland Tree Islands, Xin Wang

Open Access Dissertations

Many large terrestrial ecosystems have patterned landscapes as a result of a positive feedback system between vegetation communities and environmental factors. One example is tree island habitats in the Florida Everglades. Although they only occupy a small portion of the Everglades landscape, tree islands are important features as the focus of nutrient accumulation and wildlife biodiversity in the Everglades ecosystem. The hardwood hammock community on the elevated head of tree island habitats can accumulate high phosphorus concentration in the otherwise P-limited Everglades ecosystem. In this dissertation, I examined two hypotheses derived from the chemohydrodynamic nutrient accumulation model, which suggests that …

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Remote Estimation Of Gross Primary Production In Maize, Yi Peng, Anatoly A. Gitelson, Galina Keydan, Donald C. Rundquist, Bryan Leavitt, Shashi B. Verma, Andrew E. Suyker Jul 2010

Remote Estimation Of Gross Primary Production In Maize, Yi Peng, Anatoly A. Gitelson, Galina Keydan, Donald C. Rundquist, Bryan Leavitt, Shashi B. Verma, Andrew E. Suyker

School of Natural Resources: Faculty Publications

There is a growing interest in the estimation of gross primary productivity (GPP) in crops due to its importance in regional and global studies of carbon balance. We have found that crop GPP was closely related to its total chlorophyll content, and thus chlorophyll can be used as a proxy of GPP in crops. In this study, we tested the performance of various vegetation indices for estimating GPP. The indices were derived from spectral data collected remotely but at close-range over a period of eight years, from 2001 through 2008. The results show that chlorophyll indices, based on near infrared …

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Spectral Analysis Of Charcoal On Soils: Implications For Wildland Fire Severity Mapping Methods, Alistair M.S. Smith, Jan U. H. Eitel, Andrew T. Hudak Jan 2010

Spectral Analysis Of Charcoal On Soils: Implications For Wildland Fire Severity Mapping Methods, Alistair M.S. Smith, Jan U. H. Eitel, Andrew T. Hudak

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

Recent studies in the Western United States have supported climate scenarios that predict a higher occurrence of large and severe wildfires. Knowledge of the severity is important to infer long-term biogeochemical, ecological, and societal impacts, but understanding the sensitivity of any severity mapping method to variations in soil type and increasing charcoal (char) cover is essential before widespread adoption. Through repeated spectral analysis of increasing charcoal quantities on six representative soils, we found that addition of charcoal to each soil resulted in linear spectral mixing. We found that performance of the Normalised Burn Ratio was highly sensitive to soil type, …

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Synoptic Monitoring Of Gross Primary Productivity Of Maize Using Landsat Data, Anatoly A. Gitelson, Andrés Viña, Jeffrey G. Masek, Shashi Verma, Andrew E. Suyker Apr 2008

Synoptic Monitoring Of Gross Primary Productivity Of Maize Using Landsat Data, Anatoly A. Gitelson, Andrés Viña, Jeffrey G. Masek, Shashi Verma, Andrew E. Suyker

School of Natural Resources: Faculty Publications

There is a growing interest in monitoring the gross primary productivity (GPP) of crops due mostly to their carbon sequestration potential. Both within- and between-field variability are important components of crop GPP monitoring, particularly for the estimation of carbon budgets. In this letter, we present a new technique for daytime GPP estimation in maize based on the close and consistent relationship between GPP and crop chlorophyll content, and entirely on remotely sensed data. A recently proposed chlorophyll index (CI), which involves green and near-infrared spectral bands, was used to retrieve daytime GPP from Landsat Enhanced Thematic Mapper Plus (ETM+) data. …

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The Decline Of Fowler's Toad (Bufo Fowleri) In Southern Louisiana: Molecular Genetics, Field Experiments And Landscape Studies, Laura Sanders Vogel Aug 2007

The Decline Of Fowler's Toad (Bufo Fowleri) In Southern Louisiana: Molecular Genetics, Field Experiments And Landscape Studies, Laura Sanders Vogel

LSU New Orleans Theses and Dissertations

Two of the most pervasive threats to species biodiversity are invasive species and habitat loss and degradation. Invasive species are often relatively insensitive to disturbance and many expand their range into disturbed and fragmented habitats. This dissertation uses an interdisciplinary approach to investigate how anthropogenic habitat disturbance is precipitating a range expansion in an invasive toad species, Bufo nebulifer, which is driving a decline in its native congener, B. fowleri. I employed a remote sensing and GIS study using historical data to compare changes in the two species distributions and habitat changes, a molecular genetic study to identify interspecific hybrids …

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Environmental Variability In The Florida Keys: Impacts On Coral Reef Health, Inia M. Soto Jan 2006

Environmental Variability In The Florida Keys: Impacts On Coral Reef Health, Inia M. Soto

USF Tampa Graduate Theses and Dissertations

I examined the hypothesis that high variability in Sea Surface Temperature (SST) and ocean color are associated with higher coral cover and slower rates of decline of coral cover within the Florida Keys National Marine Sanctuary (FKNMS). Synoptic SST time series maps, covering the period 1994-2005, were constructed for the FKNMS with data collected using the National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR) satellite sensors. The SST data were compared with coral cover time series assessments at 36 sites conducted by the Coral Reef and Evaluation Monitoring Program (CREMP; 1996-2005), sponsored by the Environmental Protection …

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Censusing And Modeling The Dynamics Of A Population Of Eastern Hemlock (Tsuga Canadensis L.) Using Remote Sensing, W. Robert Lamar Dec 2003

Censusing And Modeling The Dynamics Of A Population Of Eastern Hemlock (Tsuga Canadensis L.) Using Remote Sensing, W. Robert Lamar

Graduate Theses, Dissertations, and Problem Reports (ETD)

A population of eastern hemlock (Tsuga canadensis L.) was censused from the ground using traditional field methods and from the air using large scale, high-resolution, aerial imagery in the early spring of 1997, 1998 and 1999. A manual crown survey map of the population, prepared from aerial imagery, was compared to a traditional field census. Over 60% of the individuals measured on the ground were not detected in the aerial census. Tree size, crown density and crown position all played roles in determining a crown's visibility from the air. Nearly all large, upper canopy hemlocks were visible in the aerial …

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Linear Unmixing Of Hyperspectral Signals Via Wavelet Feature Extraction, Jiang Li Dec 2002

Linear Unmixing Of Hyperspectral Signals Via Wavelet Feature Extraction, Jiang Li

Theses and Dissertations

A pixel in remotely sensed hyperspectral imagery is typically a mixture of multiple electromagnetic radiances from various ground cover materials. Spectral unmixing is a quantitative analysis procedure used to recognize constituent ground cover materials (or endmembers) and obtain their mixing proportions (or abundances) from a mixed pixel. The abundances are typically estimated using the least squares estimation (LSE) method based on the linear mixture model (LMM). This dissertation provides a complete investigation on how the use of appropriate features can improve the LSE of endmember abundances using remotely sensed hyperspectral signals. The dissertation shows how features based on signal classification …

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Seasonal Comparison Of Remotely Sensed Relative Forest Ecosystem Temperature Zones With Topography And Forest Biomass In The Clear Springs Wilderness Area Of The Shawnee National Forest, Daniel Unger Apr 2000

Seasonal Comparison Of Remotely Sensed Relative Forest Ecosystem Temperature Zones With Topography And Forest Biomass In The Clear Springs Wilderness Area Of The Shawnee National Forest, Daniel Unger

Faculty Presentations

The use of thermal infrared data to delineate seasonal relative forest ecosystem temperature zones as a tool for forest ecological studies was analyzed. Analysis involved: (1) delineating relative seasonal forest ecosystem temperature zones within the Clear Springs Wilderness Area of the Shawnee National Forest using Landsat Thematic Mapper thermal infrared data; and, (2) quantifying the effect of topography and forest biomass on relative forest ecosystem temperature zones within seasons. Results indicate that slope was statistically uncorrelated with relative temperature zones within any season, aspect was statistically correlated with relative temperature zones during fall and winter, and forest biomass was statistically …

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