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The Effects Of Urbanization On Cypress (taxodium Distichum) In Central FloridaMcCauley, Lisa A 01 January 2011 (has links)
Urbanization is accelerating in the United States and is contributing to fragmentation of natural habitats, causing changes in species composition and declines in native species. Human population growth in Orlando is typical of growth in the southeastern United States and throughout the range of cypress (Taxodium distichum). Orlando has numerous isolated cypress wetlands, called cypress domes, and many remain among the current urbanized area. This makes Orlando ideal to study the effects of urbanization on cypress domes. Specifically, I tested how urbanization and its effects on fragmentation, hydrology, and fire regime) affected (a) the numbers and spatial pattern of cypress domes in central Florida and (b) the recruitment of cypress within cypress domes. Analysis of historical loss found over 3,000 cypress domes identified in images from1984, of which 26% were lost or degraded (i.e., no longer cypressdominated) by 2004. Due to changed land use, many remaining cypress domes, formerly surrounded by natural lands, have become surrounded by urban lands causing spatial clustering and homogenization. Surprisingly, I found that both natural and urban cypress domes showed lower recruitment than agricultural cypress domes, where the natural fire regime has not been altered. The probability of cypress recruitment in cypress domes urbanized for more than 20 years is very low. Previous to that, cypress tends to recruit on the edge of cypress domes where there is less competition and hydrological conditions are more favorable. I estimate that only ~50% of the current cypress domes are recruiting and the existence of those wetlands are tied to the lifespan of the current adults. By 2104, I estimate that ~89% of the cypress domes currently recruiting will fail to recruit. I believe that reducing urban sprawl and restoring the natural fire iii regime to natural cypress domes will mitigate the current fate of cypress domes. Without this, cypress in isolated wetlands in central Florida, and providing Orlando urbanization is typical, throughout urbanized areas of the range, could be at risk. Cypress in urban areas will be then relegated to riparian zones and with unknown consequences for the species that utilize the former cypress dome habitat
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Spatial and Temporal Mapping of the Evolution of the Miami-Fort Lauderdale-West Palm Beach Metropolitan Statistical Area (MSA)Unknown Date (has links)
Urbanization is a fundamental reality in the developed and developing countries
around the world creating large concentrations of the population centering on cities and
urban centers. Cities can offer many opportunities for those residing there, including
infrastructure, health services, rescue services and more. The living space density of
cities allows for the opportunity of more effective and environmentally friendly housing,
transportation and resources. Cities play a vital role in generating economic production
as entities by themselves and as a part of larger urban complex. The benefits can provide
for extraordinary amount of people, but only if proper planning and consideration is
undertaken.
Global urbanization is a progressive evolution, unique in spatial location while
consistent to an overall growth pattern and trend. Remotely sensing these patterns from
the last forty years of space borne satellites to understand how urbanization has
developed is important to understanding past growth as well as planning for the future. Imagery from the Landsat sensor program provides the temporal component, it
was the first satellite launched in 1972, providing appropriate spatial resolution needed to
cover a large metropolitan statistical area to monitor urban growth and change on a large
scale. This research maps the urban spatial and population growth over the Miami – Fort
Lauderdale – West Palm Beach Metropolitan Statistical Area (MSA) covering Miami-
Dade, Broward, and Palm Beach counties in Southeast Florida from 1974 to 2010 using
Landsat imagery. Supervised Maximum Likelihood classification was performed with a
combination of spectral and textural training fields employed in ERDAS Image 2014 to
classify the images into urban and non-urban areas. Dasymetric mapping of the
classification results were combined with census tract data then created a coherent
depiction of the Miami – Fort Lauderdale – West Palm Beach MSA. Static maps and
animated files were created from the final datasets for enhanced visualizations and
understanding of the MSA evolution from 60-meter resolution remotely sensed Landsat
images. The simplified methodology will create a database for urban planning and
population growth as well as future work in this area. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection
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