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LAND USE EFFECTS ON LAKE WATER QUALITY IN CENTRAL FLORIDA
Title
LAND USE EFFECTS ON LAKE WATER QUALITY IN CENTRAL FLORIDA.
Creator
Seiler, Jonathan, Weishampel, John F., University of Central Florida
Abstract / Description
ABSTRACT Land use affects the water quality of lakes. Different land use types yield different effects due to varying amounts and constituents of runoff. In this study, the effects of surrounding land use on the water quality of 50 lakes in Seminole County, Florida was assessed. Using GIS, I placed buffers of 100 and 500 m around each lake. The percentages of land use type were calculated within these buffers for 1990 and 1995. An ordination of lakes was done using Canonical Correspondence...
Show moreABSTRACT Land use affects the water quality of lakes. Different land use types yield different effects due to varying amounts and constituents of runoff. In this study, the effects of surrounding land use on the water quality of 50 lakes in Seminole County, Florida was assessed. Using GIS, I placed buffers of 100 and 500 m around each lake. The percentages of land use type were calculated within these buffers for 1990 and 1995. An ordination of lakes was done using Canonical Correspondence Analysis (CCA) to determine if the surrounding land use patterns were adequate to describe the trophic status of the lakes. Correlations between land use and water quality were found to be significant for the 1990 100 and 500 m buffers. Inter-set correlations showed that among land use types: residential, urban, agriculture, hardwoods, and wetlands were the most influential in determining water quality in that they had the most positive or negative correlation with the WA scores depending on the year and buffer zone. Excessively drained and very poorly drained soils were the most influential of the soil types. A Discriminant Function Analysis (DFA) was also performed to determine which land use and soil variables were effective in discriminating between oligotrophic, mesotrophic, and eutrophic lakes. Wetlands and very poorly drained soil were the most effective in discriminating between the groups of lakes. A multiple regression analysis was performed that determined correlations for 1990 and change in land use 100 m buffers contributed to our understanding of the relationship between land use and water quality. Effects of land use on water quality need to be considered when attempting to restore a lake or subjecting it to future land development.
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Date Issued
2004
Identifier
CFE0000138, ucf:46174
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0000138
Factors limiting native species establishment on former agricultural lands
Title
Factors limiting native species establishment on former agricultural lands.
Creator
Weiler-Lazarz, Annalisa, VonHolle, Mary, Quintana-Ascencio, Pedro, Neill, Christopher, Nickerson, David, University of Central Florida
Abstract / Description
Restoration of abandoned, nonnative species-dominated agricultural lands provides opportunities for conserving declining shrubland and grassland ecosystems. Land-use legacies, such as elevated soil fertility and pH from agricultural amendments, often persist for years and can favor nonnative species at the expense of native species. Understanding the factors that limit native species establishment on abandoned agricultural lands can provide important insights for restoration and conservation...
Show moreRestoration of abandoned, nonnative species-dominated agricultural lands provides opportunities for conserving declining shrubland and grassland ecosystems. Land-use legacies, such as elevated soil fertility and pH from agricultural amendments, often persist for years and can favor nonnative species at the expense of native species. Understanding the factors that limit native species establishment on abandoned agricultural lands can provide important insights for restoration and conservation of native species on human-modified lands. I conducted two field experiments on abandoned agricultural lands: a former pasture on Martha's Vineyard, MA and a former citrus grove at Merritt Island National Wildlife Refuge (MINWR) in Titusville, FL. In these experiments I tested how soil chemical properties affect native and nonnative species abundance and how different methods of removing nonnative, invasive species affect native and nonnative species abundance. In the first experiment, specifically I tested how restoration treatments affect competition between existing nonnative agricultural plant species and native plant species that are targets for sandplain grassland restoration on Martha's Vineyard, MA. At MINWR, I examined how lowering soil fertility with carbon additions and lowering soil pH by applying sulfur affects nonnative species richness and cover (in two former citrus groves that were historically scrub/scrubby flatwoods. Overall, I found that biotic factors, such as competition with nonnative species, play a stronger role in limiting native species establishment than soil chemical properties. Likewise, control of nonnative, invasive species is most effective with mechanical treatments to physically reduce cover, rather than altering soil chemical properties.
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Date Issued
2012
Identifier
CFE0004323, ucf:49462
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0004323
Hydromorphology of the Econlockhatchee River
Title
Hydromorphology of the Econlockhatchee River.
Creator
Baker, John, Wang, Dingbao, Hagen, Scott, Chopra, Manoj, University of Central Florida
Abstract / Description
Climate change and human activities alter the hydrologic systems and exerted global scale impacts on our environment with significant implications for water resources. Climate change can be characterized by the change of precipitation and temperature, and both precipitation pattern change and global warming are associated with the increase in frequency of flooding or drought and low flows. With increasing water demand from domestic, agricultural, commercial, and industrial sectors, humans are...
Show moreClimate change and human activities alter the hydrologic systems and exerted global scale impacts on our environment with significant implications for water resources. Climate change can be characterized by the change of precipitation and temperature, and both precipitation pattern change and global warming are associated with the increase in frequency of flooding or drought and low flows. With increasing water demand from domestic, agricultural, commercial, and industrial sectors, humans are increasingly becoming a significant component of the hydrologic cycle. Human activities have transformed hydrologic processes at spatial scales ranging from local to global. Human activities affecting watershed hydrology include land use change, dam construction and reservoir operation, groundwater pumping, surface water withdrawal, irrigation, return flow, and others. In this thesis, the hydromorphology (i.e., the change of coupled hydrologic and human systems) of the Econlockhatchee River (Econ River for short) is studied. Due to the growth of the Orlando metropolitan area the Econ basin has been substantially urbanized with drastic change of the land cover. The land use / land cover change from 1940s to 2000s has been quantified by compiling existing land cover data and digitizing aerial photography images. Rainfall data have been analyzed to determine the extent that climate change has affected the river flow compared to land use change. The changes in stream flow at the annual scale and low flows are analyzed. The Econ River has experienced minimal changes in the amount of annual streamflow but significant changes to the amount of low flows. These changes are due to urbanization and other human interferences.
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Date Issued
2013
Identifier
CFE0005126, ucf:50692
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0005126
Response of Streamflow and Sediment Loading in the Apalachicola River, Florida to Climate and Land Use Land Cover Change
Title
Response of Streamflow and Sediment Loading in the Apalachicola River, Florida to Climate and Land Use Land Cover Change.
Creator
Hovenga, Paige, Medeiros, Stephen, Wang, Dingbao, Kibler, Kelly, University of Central Florida
Abstract / Description
Located in Florida's panhandle, the Apalachicola River is the southernmost reach of the Apalachicola-Chattahoochee-Flint (ACF) River basin. Streamflow and sediment drains to Apalachicola Bay in the Northern Gulf of Mexico, directly influencing the ecology of the region, in particular seagrass and oyster production. The objective of this study is to evaluate the response of runoff and sediment loading in the Apalachicola River under projected climate change scenarios and land use / land cover ...
Show moreLocated in Florida's panhandle, the Apalachicola River is the southernmost reach of the Apalachicola-Chattahoochee-Flint (ACF) River basin. Streamflow and sediment drains to Apalachicola Bay in the Northern Gulf of Mexico, directly influencing the ecology of the region, in particular seagrass and oyster production. The objective of this study is to evaluate the response of runoff and sediment loading in the Apalachicola River under projected climate change scenarios and land use / land cover (LULC) change. A hydrologic model using the Soil Water Assessment Tool (SWAT) was developed for the Apalachicola region to simulate daily discharge and sediment load under present (circa 2000) and future conditions (circa 2100) to understand how the system responds over seasonal and event time frames to changes in climate, LULC, and coupled climate / LULC. These physically-based models incorporate a digital elevation model (DEM), LULC, soil maps, climate data, and management controls. Long Ashton Research Station-Weather Generator (LARS-WG) was used to create downscaled stochastic temperature and precipitation inputs from three Global Climate Models (GCM), each under Intergovernmental Panel on Climate Change (IPCC) carbon emission scenarios for A1B, A2, and B1. Projected 2100 LULC data provided by the United States Geological Survey (USGS) EROS Center was incorporated for each corresponding IPCC scenario. Results indicate climate change may induce seasonal shifts to both runoff and sediment loading, acting to extend periods of high flow and minimum sediment loadings or altering the time at which these events occur completely. Changes in LULC showed minimal effects on flow while more sediment loading was associated with increased agriculture and urban areas and decreased forested regions. A nonlinear response for both streamflow and sediment loading was observed by coupling climate and LULC change into the hydrologic model, indicating changes in one may exacerbate or dampen the effects of the other. Peak discharge and sediment loading associated with extreme events showed both increases and decreases in the future, with variability dependent on the GCM used. Similar behavior was observed in the total discharge resulting from extreme events and increased total sediment load was frequently predicted for the A2 and A1B scenarios for simulations involving changes in climate only, LULC only, and both climate and LULC. Output from the individual GCMs predicted differing responses of streamflow and sediment loading to changes in climate on both the seasonal and event scale. Additional region-specific research is needed to better optimize the GCM ensemble and eliminate those that provide erroneous output. In addition, future assessment of the downscaling approach to capture extreme events is required. Findings from this study can be used to further understand climate and LULC implications to the Apalachicola Bay and surrounding region as well as similar fluvial estuaries while providing tools to better guide management and mitigation practices.
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Date Issued
2015
Identifier
CFE0006326, ucf:51543
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0006326
EVALUATION OF CLIMATIC AND ECOHYDROLOGICAL EFFECTS ON LONGWAVE RADIATION AND EVAPOTRANSPIRATION
Title
EVALUATION OF CLIMATIC AND ECOHYDROLOGICAL EFFECTS ON LONGWAVE RADIATION AND EVAPOTRANSPIRATION.
Creator
Rizou, Maria, Nnadi, Fidelia, University of Central Florida
Abstract / Description
Modern tools, nontraditional datasets and a better understanding of the interaction between climate and ecohydrology are continuously being developed as today's society is in critical need for improving water management, predicting hydrometeorological hazards and forecasting future climate. In particular, the study of the intra- and inter-annual variations in grass productivity and evapotranspiration caused by variations in precipitation/soil moisture and other biophysical factors is of...
Show moreModern tools, nontraditional datasets and a better understanding of the interaction between climate and ecohydrology are continuously being developed as today's society is in critical need for improving water management, predicting hydrometeorological hazards and forecasting future climate. In particular, the study of the intra- and inter-annual variations in grass productivity and evapotranspiration caused by variations in precipitation/soil moisture and other biophysical factors is of great significance due to their relation to future climatic changes. The research presented here falls in three parts. In the first part of the dissertation, a land use adaptable model, based on the superposition of the temperature and water vapor pressure effects, is proposed for the effective clear sky emissivity. Ground radiometer and meteorological data, applicable in the subtropical climate of Saint Johns River Water Management District, Florida, were utilized for the model development over the spring season of 2004. The performance of this model was systematically evaluated by pertinent comparisons with previously established models using data over various land covers. The second part of the thesis investigates the dynamics of evapotranspiration with respect to its significant environmental and biological controls over an unmanaged bahia grassland. Eddy correlation measurements were carried out at a flux tower in Central Florida over the annual course of 2004. The main focus was on the sensitivity of the water vapor flux to wetness variables, namely the volumetric soil water content and the current precipitation index. It was shown that the time scales involved with the dynamics of evapotranspiration were on the order of six days, suggesting that depletion of the soil moisture was mostly responsible for the temporal fluctuations in evapotranspiration. Finally, simple models for the Priestley-Taylor factor were employed in terms of water availability, and the modeled results closely matched the eddy covariance flux values on daily time scale during all moisture conditions. In the third part of this work, the partitioning between latent and sensible heat fluxes was systematically examined with respect to biophysical factors. It was found that the seasonal variations in leaf area index, soil water content and net radiation were reflected in a strong seasonal pattern of the energy balance. Calculations of the bulk parameters, namely Priestley-Taylor parameter and decoupling coefficient, indicated that evapotranspiration of this grassland was controlled by water supply limitations and surface conductance. At an annual basis, the cumulative evapotranspiration was 59 percent of the precipitation received at the site. The results of this research complemented with other studies will promote better understanding of land-atmosphere interactions, accurate parameterizations of hydroclimatic models, and assessment of climate impact of grassland ecosystems.
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Date Issued
2008
Identifier
CFE0002279, ucf:47851
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0002279
Relating ancient Maya land use legacies to the contemporary forest of Caracol, Belize
Title
Relating ancient Maya land use legacies to the contemporary forest of Caracol, Belize.
Creator
Hightower, Jessica, Weishampel, John, Quintana-Ascencio, Pedro, VonHolle, Mary, Chase, Arlen, University of Central Florida
Abstract / Description
Human land use legacies have significant and long lasting impacts across landscapes. However, investigating the impacts of ancient land use legacies ((>)400 years) remains problematic due to the difficulty in detecting ancient land uses, especially those beneath dense canopies. The city of Caracol, one of the most important Maya archaeological sites in Belize, was abandoned after the collapse of the Maya civilization (ca. A.D. 900), leaving behind numerous structures, causeways, and...
Show moreHuman land use legacies have significant and long lasting impacts across landscapes. However, investigating the impacts of ancient land use legacies ((>)400 years) remains problematic due to the difficulty in detecting ancient land uses, especially those beneath dense canopies. The city of Caracol, one of the most important Maya archaeological sites in Belize, was abandoned after the collapse of the Maya civilization (ca. A.D. 900), leaving behind numerous structures, causeways, and agricultural terraces that persist beneath the dense tropical forest of western Belize. LiDAR (Light Detection and Ranging) technology enables detection of below canopy Maya archaeological features, providing an ideal opportunity to study the effects of ancient land use legacies on contemporary tropical forest composition. LiDAR also provided us with a detailed record of the 3-dimensional forest structure over the 200 km2 study area. This allowed the investigation how ancient land uses continue to impact both forest composition, in terms of tree species, and forest structure. I recorded tree species over four land use categories: 1) structures, 2) causeways, 3) terraced, and 4) non-terraced land. Using non-metric multidimensional scaling (NMS) and multi-response permutation procedures (MRPP) to test for differences between the classes, I found significantly distinct tree communities associated with the presence of terraces and the underlying topography. Terraced slopes appear to function as micro-valleys on the side of a hill, creating an environmental "bridge" between slope and valley tree communities. Tree species composition over causeways and structures was also found to be significantly different from terraced and non-terraced plots. Forest structure was assessed by extracting LiDAR points for terraced (n=150) and non-terraced (n=150) 0.25 ha plots. I calculated average canopy height, canopy closure, and vertical diversity from the height bins of the LiDAR points, using slope, elevation, and aspect as covariates. Using PerMANOVA I determined that forest structure over terraces was significantly different from non-terraced land. Terraces appear to mediate the effect of slope, resulting in less structural variation between slope and non-sloped land. These results led to the conclusion that human land uses abandoned (>)1000 years ago continue to impact the contemporary forests.
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Date Issued
2012
Identifier
CFE0004250, ucf:49497
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0004250
Land use effects on energy and water balance-developing a land use adapted drought index
Title
Land use effects on energy and water balance-developing a land use adapted drought index.
Creator
Cheng, Chi-Han, Nnadi, Fidelia, Chopra, Manoj, Wang, Dingbao, Sumner, David, University of Central Florida
Abstract / Description
Climate change is expected to increase the frequency, intensity and duration of droughts in all parts of the United States (US). Snow packs are disappearing earlier in the spring and summer, with reduced stream-flow. Lower reservoir levels, higher temperatures, and greater precipitation variability have been observed. Drought events in the US have threatened drinking water supplies for communities in Maryland and Chesapeake Bay as observed in 2001 through September 2002; Lake Mead in Las...
Show moreClimate change is expected to increase the frequency, intensity and duration of droughts in all parts of the United States (US). Snow packs are disappearing earlier in the spring and summer, with reduced stream-flow. Lower reservoir levels, higher temperatures, and greater precipitation variability have been observed. Drought events in the US have threatened drinking water supplies for communities in Maryland and Chesapeake Bay as observed in 2001 through September 2002; Lake Mead in Las Vegas in 2000 through 2004; Peace River and Lake Okeechobee in South Florida in 2006; and Lake Lanier in Atlanta, Georgia in 2007. ENSO influences the climate of Florida; where El Ni(&)#241;o years tend to be cooler and wetter, while La Ni(&)#241;a years tend to be warmer and drier than normal in the fall through the spring, with the strongest effect in the winter. Both prolonged heavy rainfall and drought potentially have impacts on land uses and many aspects of Florida's economy and quality of life. Drought indices could integrate various hydrological and meteorological parameters and quantify climate anomalies in terms of intensity, duration, and spatial extent, thus making it easier to communicate information to diverse users. Hence, understanding local ENSO patterns on regional scales and developing a new land use drought index in Florida are critical in agriculture and water resources planning and managements. Current drought indices have limitations and drawbacks such as calculation using climate data from meteorological stations, which are point measurements. In addition, weather stations are scarce in remote areas and are not uniformly distributed. Currently used drought indices like the PDSI and the Standardized Precipitation Index (SPI) could not fully demonstrate the land use effects. Other limitations include no single index that addresses universal drought impact. Hence, there is a renewed interest to develop a new (")Regional Land Use Drought Index (RLDI) that could be applied for various land use areas and serve for short term water resources planning. In this study, the first and second research topics investigated water and energy budgets on the specific and important land use areas (urban, forest, agriculture and lake) in the State of Florida by using the North American Regional Reanalysis (NARR) reanalysis data. NARR data were used to understand how drought events, EI Ni(&)#241;o, La Ni(&)#241;a, and seasonal and inter-annual variations in climatic variables affect the hydrologic and energy cycle over different land use areas. The results showed that the NARR data could provide valuable, independent analysis of the water and energy budgets for various land uses in Florida. Finally, the high resolution land use (32km(&)#215;32km) adapted drought indices were developed based on the NARR data from 1979 to 2002. The new regional land use drought indices were developed from normalized Bowen ratio and the results showed that they could reflect not only the level of severity in drought events resulting from land use effects, but also La Ni(&)#241;a driven drought impacts.
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Date Issued
2012
Identifier
CFE0004344, ucf:49410
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0004344
THE EFFECTS OF URBANIZATION ON THE STRUCTURE, QUALITY, AND DIVERSITY OF CYPRESS PLANT COMMUNITIES IN CENTRAL FLORIDA
Title
THE EFFECTS OF URBANIZATION ON THE STRUCTURE, QUALITY, AND DIVERSITY OF CYPRESS PLANT COMMUNITIES IN CENTRAL FLORIDA.
Creator
Knickerbocker, Courtney, Quigley, Martin, University of Central Florida
Abstract / Description
The integrity of wetland ecosystems is largely determined by hydrological functionality, degree of connectivity to like ecosystems, and permeability to external influence. Land use changes in upland areas adjacent to wetland ecosystems may influence hydrology and connectivity while introducing novel biotic and abiotic materials. There is an increasing trend toward the use of remote assessment techniques to determine the degree of impact of external influences on adjacent wetlands. Remote...
Show moreThe integrity of wetland ecosystems is largely determined by hydrological functionality, degree of connectivity to like ecosystems, and permeability to external influence. Land use changes in upland areas adjacent to wetland ecosystems may influence hydrology and connectivity while introducing novel biotic and abiotic materials. There is an increasing trend toward the use of remote assessment techniques to determine the degree of impact of external influences on adjacent wetlands. Remote assessment and predictive capabilities are provided by indices such as the Landscape Development Intensity Index (LDI) (Brown and Vivas 2005) which may be beneficial in determining site condition, and which have the added benefit of providing a quantitative gradient of human impact. This study assessed the predictive ability of the LDI in cypress ecosystems, by testing its correlations with plant community metrics including an index of floral quality calculated using coefficients of conservatism (CC)(Cohen et al. 2004), plant species diversity, and fluctuation in community composition assessed by changes in the wetland status and native status of component plant species. LDI was also compared against an independent measure of disturbance which was used to construct an a priori disturbance gradient. Overall, diversity measures showed little correlation with any of the disturbance indices, while CC scores were significantly correlated. Models were constructed in an attempt to explain each of the variables of plant community response to development in the surrounding landscape. The length of time since the development of the land adjacent to the cypress domes was a predictor of plant community response only when included in models with other variables. LDI was the strongest predictor in all models except where increases in land use associated with hydrological changes helped predict or better predicted proportions of exotic and upland species.
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Date Issued
2009
Identifier
CFE0002576, ucf:48280
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0002576