Physical and Environmental Geography Commons^™

Analysis Of Small Lake Water Level Fluctuations By Remote Sensing In Twin Lake, Michigan., Eric Carballido

Masters Theses

Accurate analysis of lake level fluctuations is critical for water resources management. However, it remains a challenge to estimate lake level fluctuations in ungauged small lakes such as East Twin Lake. Located in Twin Lake, Michigan, East Twin Lake has experienced a drastic reduction in water surface area since 2020. To understand the nature of water level fluctuations in East Twin Lake, this study utilized a combination of Landsat and National Agriculture Imagery Program (NAIP) data to make surface water area estimations of East Twin Lake for the period of 1993-2022. In total, 27 years of water surface area estimations …

Linkages Between Atmospheric Circulation, Weather, Climate, Land Cover And Social Dynamics Of The Tibetan Plateau, Shobha Kumari Yadav

Graduate Theses, Dissertations, and Problem Reports

The Tibetan Plateau (TP) is an important landmass that plays a significant role in both regional and global climates. In recent decades, the TP has undergone significant changes due to climate and human activities. Since the 1980s anthropogenic activities, such as the stocking of livestock, land cover change, permafrost degradation, urbanization, highway construction, deforestation and desertification, and unsustainable land management practices, have greatly increased over the TP. As a result, grasslands have undergone rapid degradation and have altered the land surface which in turn has altered the exchange of heat and moisture properties between land and the atmosphere. But gaps …

Monitoring Bull Kelp (Nereocystis Leutkeana) Remotely At High Resolutions, Hannah E. Joss

Cal Poly Humboldt theses and projects

Bull kelp (Nereocystis leutkeana) is a foundational seaweed in nearshore, marine systems, traditionally supporting economically important fisheries, extracting nutrients in its vicinity, and sequestering carbon and transporting it great distances to subsidize shallow and deep-sea environments. Bull kelp is also a culturally important species for some indigenous peoples along the northeastern Pacific coastline and provides a harvestable product with growing demand. Global trends in kelp distribution show patterns of decline, and the immense loss of northern California bull kelp forests in response to climatic changes have highlighted the need for alternative sources of kelp, both for the product …

Geologic Mapping Of The Sparta 7.5-Minute Quadrangle In Northern Mississippi Via Remote Sensing, Traditional Geologic Survey, And Applied Geospatial Information Systems Methods, Rayford Dean Parnell

Theses and Dissertations

Traditional geologic mapping involves substantial time and labor in the field as geologic contacts are manually examined and interpreted. The processes of mapping geologic contacts can be condensed into a quicker and less laborious process using advances in remote sensing and GIS (geospatial information systems), including increased resolution and computerized data management and interpretation. Application of these advances reduces the costs and time of geologic mapping. The Sparta 7.5-minute quadrangle provides a mostly unaltered view of regional Paleocene and Upper Cretaceous geology due to its rural locale, lack of development, and stream topography. Recently LiDAR (Light Detection And Ranging) survey …

Influence Of Altitude And Scan Angle On Uas-Lidar Ground Height Measurement Accuracy In Juncus Roemerianus Scheele (Black Needle Rush)-Dominated Marshes, Michael Amelunke

Master's Theses

Coastal marshes are influenced by complex interactions among environmental and human factors. Marsh plant communities exist across subtle elevation gradients which are highly influenced by the local tidal regime. To better understand these dynamic conditions, improved methodologies for acquiring accurate elevation values are a necessity in marsh research and management. However, overestimation of marsh elevation values obtained from remote sensing is common due to vegetation characteristics. The goal of this study was to address this problem by determining the optimum altitude and scan angle for Light Detection and Ranging (LiDAR) collection using an Unmanned Aerial System (UAS) within Juncus roemerianus …

Short-Term 2d And 3d Geomorphic Change Detection At A Public Park On Lake Michigan Using Uas Remote Sensing Techniques, Scott Patrick Fitzgerald

Masters Theses

The high-water level of Lake Michigan (LM) in the past few years has led to significant periods of erosion and increased the risk to private property owners on the coast. To cope with this, many property owners on the coast of LM have constructed coastal protections, some opting for seawalls. Previous studies have assessed the effects of seawalls but disagreed on their impacts, and only laboratory studies were able to establish their range of influence. Using a different method to study their effects will be pertinent to understanding them.

This research aims to use a higher temporal and spatial resolution …

Arctic Greening: Characterizing Tundra Vegetation From In-Situ And Remotely Sensed Observations, Shira Ann Ellenson

Graduate Student Theses, Dissertations, & Professional Papers

As the Arctic has warmed at twice the rate of the global average, vegetation productivity has also been increasing. While satellite remote sensing is useful for summarizing Arctic-wide trends, changes in tundra species heights, densities, composition, and distribution can be missed at coarse resolution. Smaller, plot-scale studies are necessary to better understand vegetation dynamics at fine scales occurring on the ground.

In 1995, high-resolution traditional aerial photographs and in-situ measurements of vegetation characteristics were taken at a series of plots established on the Alaskan North Slope. Repeat field surveys in 2021 revealed increases in plant cover for deciduous shrubs and …

Digital Earth: The Impact Of Geographic Technology Through The Ages, Mishka Vance Huq

Theses and Dissertations

Geographic technology encompasses a wide range of geographic knowledge, concepts, processes, and artifacts. Because of its interdisciplinarity and integration with other technologies, the paper examines the diffuse impacts of geographic technology within the evolving relationship between technological and societal developments over time.

Identifying Smokestacks In Remotely Sensed Imagery Via Deep Learning Algorithms, Kenneth Moss

Masters Theses

Locating smokestacks in remote sensing imagery is a crucial first step to calculating smokestack heights, which allows for the accurate modeling of dioxin pollution spread and the study of resulting health impacts. In the interest of automating this process, this thesis examines deep learning networks and how changes in input datasets and network architecture affect image detection accuracy. This initial image detection serves as the first step in automated object recognition and height calculation. While this is applicable to general land use classification, this study specifically addresses detecting smokestack images. Different dataset scenarios are generated from the massive Functional Map …

Airborne Observations Of Thermal Anisotropy From Urban Residential Neighbourhoods In Salt Lake City, Utah, Samantha J. Claessens

Electronic Thesis and Dissertation Repository

Urban surface temperatures are important variables in urban climatological processes. This thesis examines the directional variability of remotely sensed urban surface temperatures (thermal anisotropy or Λ) for three vegetated residential neighbourhoods in Salt Lake City, Utah, USA. Airborne thermal remote sensing using a thermal imager sampled the directional brightness temperature (DBT) at three times within a day for each site. Results indicate that temporal variability over a 20 – 30-minute flight was not negligible. Average DBT were then extracted from atmospherically corrected images and plotted on polar plots. For low density residential neighbourhoods Λ is increased with increasing tree-canopy coverage …

Responses Of Land Surface Phenology To Wildfire Disturbances In The Western United States Forests, Jianmin Wang

Electronic Theses and Dissertations

Land surface phenology (LSP) characterizes the seasonal dynamics in the vegetation communities observed for a satellite pixel and it has been widely associated with global climate change. However, LSP and its long-term trend can be influenced by land disturbance events, which could greatly interrupt the LSP responses to climate change. Wildfire is one of the main disturbance agents in the western United States (US) forests, but its impacts on LSP have not been investigated yet. To gain a comprehensive understanding of the LSP responses to wildfires in the western US forests, this dissertation focused on three research objectives: (1) to …

The Importance Of Landscape Position Information And Elevation Uncertainty For Barrier Island Habitat Mapping And Modeling, Nicholas Matthew Enwright

LSU Doctoral Dissertations

Barrier islands provide important ecosystem services, including storm protection and erosion control to the mainland, habitat for fish and wildlife, and tourism. As a result, natural resource managers are concerned with monitoring changes to these islands and modeling future states of these environments. Landscape position, such as elevation and distance from shore, influences habitat coverage on barrier islands by regulating exposure to abiotic factors, including waves, tides, and salt spray. Geographers commonly use aerial topographic lidar data for extracting landscape position information. However, researchers rarely consider lidar elevation uncertainty when using automated processes for extracting elevation-dependent habitats from lidar data. …

Detecting Coastal Marsh Change From Aerial Imagery Using Spectral And Textural Methods: Pascagoula River Estuary, Mississippi, 1955-2014, Margaret Claire Bell Waldron

Master's Theses

As sea level rise accelerates, coastal marsh ecosystems are increasingly vulnerable. Vertical accretion rates must exceed or keep pace with rates of sea level rise to prevent transition to open water or inland migration of marsh vegetation. While some marsh systems along the northern Gulf of Mexico coast have remained stable, others, e.g., the marshes of the Louisiana Gulf Coast, have experienced high rates of conversion to open water. This study examined the historical extent of intertidal marsh at the mouth of the Pascagoula River in Jackson County, Mississippi to determine whether marsh extent changed during the period 1955-2014 and …

Crown-Level Mapping Of Tree Species And Health From Remote Sensing Of Rural And Urban Forests, Fang Fang

Graduate Theses, Dissertations, and Problem Reports

Tree species composition and health are key attributes for rural and urban forest biodiversity, and ecosystem services preservation. Remote sensing has facilitated extraordinary advances in estimating and mapping tree species composition and health. Yet previous sensors and algorithms were largely unable to resolve individual tree crowns and discriminate tree species or health classes at this essential spatial scale due to the low image spectral and spatial resolution. However, current available very high spatial resolution (VHR) remote sensing data can begin to resolve individual tree crowns and measure their spectral and structural qualities with unprecedented precision. Moreover, various machine learning algorithms …

The Effect Of Sub-Facet Scale Geometry On Vertical Facet Temperatures In Urban Street Canyons, Rainer V.J. Hilland

Electronic Thesis and Dissertation Repository

Surface temperature plays a key role in many micro-scale urban processes. Walls comprise a significant percentage of the urban surface, yet are under-represented by many methods of thermal remote sensing and not considered in detail by micro-scale surface temperature mod- els. This thesis presents a novel method of mobile thermal observation performed in urban street canyons in London, ON that uses a thermal imager as well as a visual spectrum camera to provide dense spatial and temporal resolution of micro-scale wall temperature distributions. Images are manually classified by a series of nominal variables and the resulting data set discusses the …

Impact Of Drought On Land Cover Changes In Diné Bikéyah – A Study Through Remote Sensing, Anjanette A.J. Hawk

Geography ETDs

This study identifies land cover changes associated with a ten-year drought period and discusses the importance of vegetation change in Diné Bikéyah, a semi-arid land located in a remote part of the southwestern United States (US). This study concludes that drought produced slight changes in vegetation within a 540 km² study area in the Tselani-Cottonwood Chapter (TCC) in Diné Bikéyah. The data for this study consist of three Landsat images for the years 1998, 2002, and 2009. The methods used to analyze these Landsat images included image pre-processing, calculation of normalized difference vegetation index (NDVI) images, and supervised (maximum …

Greening Of The Arctic: Plot-Scale Analysis Of Interactions Between Climate, Vegetation, And Permafrost At Toolik Lake, Alaska (1995 - 2017), Brianna Rick

Graduate Student Theses, Dissertations, & Professional Papers

Air temperatures across the Arctic have increased in recent decades, and through complex feedbacks, vegetation and permafrost (frozen ground) are actively responding as climate warming continues. This study investigates the trends and interactions of observed air, soil-surface temperature (SST), and active-layer thickness (ALT) at Toolik Lake on the Alaskan North Slope between 1995 and 2017, as well as vegetation change over time.

Time series between 1995 and 2017 at CALM site U12B, a 1 ha plot near Toolik Lake, reveal an increase (0.50 °C/decade) in mean summer (Jun-Aug) air temperatures and a decrease (­0.23 °C/decade) in mean summer SST. In …

A Study Of African Savanna Vegetation Structure, Patterning, And Change, Christoffer R. Axelsson

Electronic Theses and Dissertations

African savannas cover roughly half of the continent, are home to a great diversity of wildlife, and provide ecosystem services to large populations. Savannas showcase a great diversity in vegetation structure, resulting from variation in climatic, edaphic, topographic, and biological factors. Fires play a large role as savannas are the most frequently burned ecosystems on Earth. To study how savanna vegetation structure shifts with environmental factors, it is necessary to gather site data covering the full gradient of climatic and edaphic conditions. Several earlier studies have used coarse resolution satellite remote sensing data to study variation in woody cover. These …

Mapping And Risk Assessment Of Juniper Encroachment Into A Prairie Landscape, Kyle D. Kaskie

Electronic Theses and Dissertations

Juniper encroachment is a considerable threat to the prairie ecosystems of the Great Plains because it has the potential to alter native grasslands by changing soil characteristics, limiting herbaceous biomass, and hindering native community regeneration. Accurate maps of juniper cover and predictions of areas at risk for future expansion are needed to support proactive management measures. Therefore, our objectives are to: (1) Develop a practical workflow for large-scale juniper mapping using Landsat 8 Operational Land Imager (OLI) imagery and partial unmixing techniques, (2) Compare the classification accuracies from the resulting map based on different juniper density thresholds and different types …

Simulating The Impacts Of Land-Use Land-Cover Changes On Cropland Carbon Fluxes In The Midwest Of The United States, Zhengpeng Li

Electronic Theses and Dissertations

Understanding the major drivers of the cropland carbon fluxes is important for carbon management and greenhouse gas mitigation in agriculture. Past studies found that agricultural land-use and land-cover (LULC) changes, such as changes in cropland production technologies, tillage practices, and planted crop species, could have large impacts on carbon fluxes. However, the impacts remain highly uncertain at regional to global scales. Satellite remote sensing is commonly used to create products with geospatial information on LULC changes. This geospatial information can be integrated into biogeochemical models to simulate the spatial and temporal patterns of carbon fluxes. We used the General Ensemble …

Integrated (Remote Sensing, Gis, And Modeling) Hydrological Investigation And Landslide Susceptibility Studies In The Arabian Shield, Talal Ghazi Alharbi

Dissertations

An integrated approach (remote sensing, geographical information systems [GIS], and modeling) was applied to conduct a number of hydrologic and environmental investigations in the Arabian Peninsula (AP) aimed at: (1) identifying the spatial and temporal climate change–related variations in precipitation over the AP using readily available, remotely acquired global precipitation data sets; (2) investigating the nature of the factors controlling the observed climatic variations; (3) estimating the partitioning of precipitation over the Red Sea Hills watersheds into runoff , recharge, and initial losses using calibrated continuous rainfall runoff models (Soil Water Assessment Tool [SWAT]); (4) identifying landslide (largely caused by …

Prospects For An International Charter "Space And Major Disaster" Remote Sensing Response To Drought Disasters - An Anhui, China Case Study, Joseph Burkhead

Masters Theses

Remote sensing is often leveraged during the response phase of disaster management to improve the situational awareness of decision-makers. The International Charter "Space and Major Disaster" (Charter) provides remote sensing support to non-spacefaring nations facing disasters such as earthquakes, floods and tsunamis. However, the Charter has never activated for a major drought disaster. Since droughts affect over half of the nearly 3 billion people that suffer from natural disasters annually, this study seeks to determine whether satellite remote sensing can be effectively employed according to the intent, capabilities, and limitations of the Charter to benefit officials responding to a major …

Comparing Twenty-Four Years Of Forest Change In Two Communities Of Mexico's Meseta PuréPecha Using Multi-Spectral Satellite Imagery, Kevin Scott Martin

Dissertations and Theses

The Meseta Purépecha, a volcanic plateau in the Mexican state of Michoacan, is home to one of the most species-rich pine forests in the world. Recent increases in demand for forest products has put added pressure on these resources. Though existing research has suggested significant deforestation in the Meseta, there is little information identifying specific areas of decline. This study focuses on two indigenous communities in the Meseta--Pichátaro and Sevina. Both communities have long relied on wood as an economic resource. However, the two communities have reacted differently to increased demand for forest resources. The purpose of this study is …