Assessing Urban Expansion and Hotspots of Land Use and Land Cover (LULC) Change in the Tri-Cities, Tennessee.
Location
D.P. Culp Center Ballroom
Start Date
4-5-2024 9:00 AM
End Date
4-5-2024 11:30 AM
Poster Number
148
Name of Project's Faculty Sponsor
Ingrid Luffman
Faculty Sponsor's Department
Geosciences
Competition Type
Competitive
Type
Poster Presentation
Presentation Category
Science, Technology and Engineering
Abstract or Artist's Statement
Bristol, Johnson City, and Kingsport, Tennessee, collectively known as the Tri-Cities, have experienced notable Land Use and Land Cover (LULC) changes, with urban expansion leading to increased developed land and population growth in the last two decades. The Tri-Cities (Bristol, Kingsport, and Johnson City) city footprints have increased by 15% in land area since 2000, concurrent with heightened urban development. This study assesses the urban expansion and Land Use and Land Cover (LULC) changes of the Tri-Cities and examines hotspots of built-up areas and transitions from vegetation to built-up in Tri-Cities, Tennessee, from 2001 to 2021. LULC data at a 30m resolution for 2001 and 2021 were downloaded from the National Land Cover Database (NLCD) and city boundary data were obtained from the Tri-City Development Council. The urban landscape in the Tri-Cities region reflects dynamic city boundary expansions for Johnson City, Kingsport, and Bristol. Kingsport notably led in urban expansion with a remarkable 18%, while Bristol's boundary increment remained more conservative at 7%. LULC change was evaluated within the city footprints using change detection analysis based on nine land use classes. Low, medium, and high-intensity developed land were categorized as built-up areas, while forest, shrub, herbaceous, pasture, and croplands were classified as vegetation land among the land use types. Change detection analysis highlights a transformation in land use classes, with open water, forest, and cultivated areas experiencing loss, while developed land, barren land, shrubland, herbaceous land, and wetlands exhibit gains. Notably, 3.7% of cultivated lands shifted to developed areas, signifying a loss of productive farmland. Northwestern Johnson City, southeastern Kingsport, and southwestern Bristol experienced the most significant increases in developed land converted from cultivated areas, emphasizing the urbanization trend. Nearest Neighbor Index (NNI) analysis was employed for spatial clustering detection, with cluster locations identified using the Nearest Neighbor Hierarchical Clustering (NNHC) method, defining a cluster as 25 points in a one-mile radius. Kernel Density Estimation (KDE) with a quartic kernel and 1-mile bandwidth was used to create a heat map of LULC changes from vegetation to built-up. LULC change from 2001 to 2021 yields NNI values of 0.3182 for built-up areas and 0.2157 for converted built-up areas from vegetation land, indicating spatial clustering across the Tri-Cities region. KDE reveals intense built-up areas throughout the study region, with hotspots at recent annexation boundaries. Johnson City and Bristol demonstrate distinct patterns of vegetation-to-built-up change along these annexation limits, while Kingsport displays comparatively lower hotspot intensity despite significant urban expansion. This LULC conversion increases impervious areas, reducing infiltration rates and contributing to urban flooding. These findings will provide valuable insights for future research on the potential effects of LULC change on flooding in Tri-Cities, Tennessee.
Assessing Urban Expansion and Hotspots of Land Use and Land Cover (LULC) Change in the Tri-Cities, Tennessee.
D.P. Culp Center Ballroom
Bristol, Johnson City, and Kingsport, Tennessee, collectively known as the Tri-Cities, have experienced notable Land Use and Land Cover (LULC) changes, with urban expansion leading to increased developed land and population growth in the last two decades. The Tri-Cities (Bristol, Kingsport, and Johnson City) city footprints have increased by 15% in land area since 2000, concurrent with heightened urban development. This study assesses the urban expansion and Land Use and Land Cover (LULC) changes of the Tri-Cities and examines hotspots of built-up areas and transitions from vegetation to built-up in Tri-Cities, Tennessee, from 2001 to 2021. LULC data at a 30m resolution for 2001 and 2021 were downloaded from the National Land Cover Database (NLCD) and city boundary data were obtained from the Tri-City Development Council. The urban landscape in the Tri-Cities region reflects dynamic city boundary expansions for Johnson City, Kingsport, and Bristol. Kingsport notably led in urban expansion with a remarkable 18%, while Bristol's boundary increment remained more conservative at 7%. LULC change was evaluated within the city footprints using change detection analysis based on nine land use classes. Low, medium, and high-intensity developed land were categorized as built-up areas, while forest, shrub, herbaceous, pasture, and croplands were classified as vegetation land among the land use types. Change detection analysis highlights a transformation in land use classes, with open water, forest, and cultivated areas experiencing loss, while developed land, barren land, shrubland, herbaceous land, and wetlands exhibit gains. Notably, 3.7% of cultivated lands shifted to developed areas, signifying a loss of productive farmland. Northwestern Johnson City, southeastern Kingsport, and southwestern Bristol experienced the most significant increases in developed land converted from cultivated areas, emphasizing the urbanization trend. Nearest Neighbor Index (NNI) analysis was employed for spatial clustering detection, with cluster locations identified using the Nearest Neighbor Hierarchical Clustering (NNHC) method, defining a cluster as 25 points in a one-mile radius. Kernel Density Estimation (KDE) with a quartic kernel and 1-mile bandwidth was used to create a heat map of LULC changes from vegetation to built-up. LULC change from 2001 to 2021 yields NNI values of 0.3182 for built-up areas and 0.2157 for converted built-up areas from vegetation land, indicating spatial clustering across the Tri-Cities region. KDE reveals intense built-up areas throughout the study region, with hotspots at recent annexation boundaries. Johnson City and Bristol demonstrate distinct patterns of vegetation-to-built-up change along these annexation limits, while Kingsport displays comparatively lower hotspot intensity despite significant urban expansion. This LULC conversion increases impervious areas, reducing infiltration rates and contributing to urban flooding. These findings will provide valuable insights for future research on the potential effects of LULC change on flooding in Tri-Cities, Tennessee.