Current Search: environmental variation (x)
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- Title
- EFFECTS OF REAL ESTATE CYCLES ON RESIDENTIAL AMENITY VALUES FOR WATER RESOURCES.
- Creator
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Hillard, Amy, Milon, Walter, University of Central Florida
- Abstract / Description
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Little research has been conducted on the effects of housing price cycles on preferences for environmental landscape attributes over time (Cho, Kim, & Roberts, 2011). If the economic value of scarce resources like water resource amenities depends on consumer preferences, then it is useful to address possible effects of cyclical variation in the housing market on these values. This issue is addressed in the primary research question for this thesis: Did the 2007-2009 recession and consequent...
Show moreLittle research has been conducted on the effects of housing price cycles on preferences for environmental landscape attributes over time (Cho, Kim, & Roberts, 2011). If the economic value of scarce resources like water resource amenities depends on consumer preferences, then it is useful to address possible effects of cyclical variation in the housing market on these values. This issue is addressed in the primary research question for this thesis: Did the 2007-2009 recession and consequent real estate bust affect marginal willingness to pay for water resource amenities for properties in proximity to the lower St. Johns River (SJR) in Duval County, FL? Prior published studies on the most recent real estate cycle were used to evaluate the timing of housing market impacts during the most recent recession. Also, sales price and sales volume distributions for Duval County were evaluated to compare trends. Based on prior research and results, three separate hypotheses were generated and tested using the hedonic pricing method for residential properties in Duval County. The first hypothesis was that the recent recession impacted the implicit prices of water resource amenities for residential properties in proximity to the SJR. Two separate regression models were developed to test different recession periods (2007-2012 and 2008-2012) based on sample data. Time fixed effect binary variables were used to construct recession interaction effects with water related amenities (proximity to the SJR as well as tributary and riverfront properties). Results showed that during the recession period, sales prices for houses further away from the river experienced a greater negative impact than those closer to the river. This result is similar to research by Cohen, Coughlin, and Lopez (2012) who suggest that, higher priced or high tier residential houses (in this case, those closer to river) tend to hold their value more than low tier residential houses. Also, consistent with research by Bin, Czajkowski, Jingyuan, and Villarini (2015), sales prices for tributary and riverfront homes were not impacted by the recession. A second hypothesis was developed to test whether sales prices for houses in Duval County recovered to pre-recession levels. A regression model was constructed with a separate recession interaction effect variable for 2013-2015 and results indicated that the housing market did not make a full recovery from the recession. A final hypothesis was developed on the significance of interaction variables water quality indicator Chlorophyll-A and a recession effects binary variable. All water quality interaction variables introduced within the model were not significant at the 1% or 5% levels. Future research might include testing interactions with parcel land area and recession time effects and also examining other water quality indicators including Secchi Disk, dissolved oxygen, or turbidity. It may also be useful in the future to use an alternative method of measuring implicit prices of environmental characteristics, such as the repeat sales method.
Show less - Date Issued
- 2015
- Identifier
- CFH0004890, ucf:45423
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH0004890
- Title
- TREEFROG (HYLA SQUIRELLA) RESPONSES TO RANGELAND MANAGEMENT IN SEMI-TROPICAL FLORIDA, USA.
- Creator
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Windes, Kathryn, Fauth, John, University of Central Florida
- Abstract / Description
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As urban areas expand, agricultural lands become increasingly important habitat for many species. Compared to some types of agricultural land-use, ranchlands provide vast expanses of minimally modified habitat that support many threatened and endangered species. Conservation biologists can promote ecologically sound management approaches by quantifying the effects of agricultural practices on resident species. I examined the effects of pasture management, cattle grazing, and landscape...
Show moreAs urban areas expand, agricultural lands become increasingly important habitat for many species. Compared to some types of agricultural land-use, ranchlands provide vast expanses of minimally modified habitat that support many threatened and endangered species. Conservation biologists can promote ecologically sound management approaches by quantifying the effects of agricultural practices on resident species. I examined the effects of pasture management, cattle grazing, and landscape characteristics on both adult and larval treefrogs in a ranchland in south-central Florida. I experimentally determined optimal deployment of artificial treefrog shelters constructed of polyvinylchloride (PVC) pipe to efficiently sample adult treefrogs (Chapter 1). Seventy-two shelters were hung on oak trees (Quercus virginiana) and cabbage palm trees (Sabal palmetto) with smooth trunks or boots (residual palm fronds), at all possible combinations of three heights (2, 3, and 4 m), four compass directions (N, S, E, and W) and two water levels (with or without 10 cm). Shelter residence was completely dominated by the Squirrel Treefrog, Hyla squirella (N = 65). Significantly fewer H. squirella were found in shelters on palms with boots than on smooth palms or oak trees (0.29 ñ 0.21 [mean ñ 1 SE hereinafter] versus 1.3 ñ 0.21 and 1.1 ñ 0.21, respectively), and shelters with water had slightly more H. squirella than those without (1.5 ñ 0.19 versus 0.88 ñ 0.19, respectively). Orientation and height did not affect the number of treefrogs encountered; thus, the optimal protocol is to deploy shelters on either smooth palms or oak trees, with water, at 2 m height for easy sampling, and in random compass orientations. I used this protocol to sample H. squirella in woodlots surrounding twelve wetlands and examined how time, frog stage and sex, and landscape features influenced treefrog survival, recapture and site fidelity (Chapter 2). I deployed 15 shelters/ha of woodlot within a 100 m buffer around each wetland. I sampled shelters three times during the fall breeding season, removed all shelters to force frogs to overwinter in natural refugia, and replaced shelters for the final spring sampling. During sampling periods, I sexed, measured, and individually marked each frog using visual implant elastomer (VIE) tags. I used Program MARK to build linear models that included either gender group (female, male or juvenile) or life history stage (adult, juvenile) and either time (sampling interval 1, 2, or 3) or season (fall, spring). I used the most informative model as a null model to assess effects of landscape covariates on survival and recapture. Females had higher survival than either males or juveniles, for which estimates were similar (0.867 vs 0.741 and 0.783, respectively). Survival did not vary over time, although there was some support for an effect of season, with lower survival during the final over-wintering period than in the fall intervals (relative variable importance: group = 0.730; stage = 0.134; time = 0.200; season = 0.310). Adults had higher recapture rates than juveniles (average recapture 0.214 vs 0.102), and recapture for both stages varied over time, with highest recapture in sampling interval two (relative variable importance: group = 0.262; stage = 0.514; time = 0.513; season = 0.229). Hyla squirella was extremely site loyal; no individuals moved between sampling sites, and 95% of recaptured individuals were in their original shelter. Strong terrestrial site fidelity calls into question the traditional ÃÂ"ponds as patchesÃÂ" metapopulation view of treefrog population dynamics. Area of woodlot within 250 m was the most important landscape variable in explaining additional variation in both survival and recapture. Frogs had higher survival and lower recapture in larger woodlots, indicating that intact, contiguous woodlots are higher quality habitat than more fragmented woodlots. Neither survival nor recapture varied with wetland grazing treatments or between pasture types. Finally, I experimentally assessed the effects of cattle grazing and pasture management on larval H. squirella. I selected four wetlands: two in semi-natural pastures (SN) and two in intensively managed pastures (IM). One wetland in each pasture type was fenced so that it was released from cattle grazing (R). I collected three clutches of H. squirella eggs (Clutches A, B, and C) and reared tadpoles in the laboratory until Gosner stage 25. In each wetland, I deployed a total of 50 tadpoles from each clutch into 105 L pens constructed of plastic laundry baskets and mesh window screening. Clutch significantly affected tadpole survival, with Clutch A having the highest percent survival, followed by Clutch B and finally Clutch C (41.66, 32.11 à53.95 [mean, 95% confidence limits hereinafter]; 9.00, 6.76 à11.88; 2.89, 2.02 à4.01, respectively). Wetland type also affected survival, with SN wetlands supporting significantly higher survival than IM wetlands (SN-R: 53.95, 32.88 à88.13; SN-G: 18.95, 11.30 à31.36 vs IM-R: 7.32, 4.13 à12.49; IM-G: 1.09, 0.29 à2.39). Genetic variation in survival confirms the potential for H. squirella to adapt to rangeland management, but extremely low survival of some clutches indicates that few clutches may be able to survive in low quality wetlands, such as IM-G wetlands. Higher survival in SN pasture wetlands suggest this is a superior habitat and future management objectives should conserve semi-natural pastures and limit further modification of intensively managed pastures, including removing woodlots near wetlands.
Show less - Date Issued
- 2010
- Identifier
- CFE0003178, ucf:48592
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003178
- Title
- FACTORS AFFECTING PREDATION OF MARINE TURTLE EGGS BY RACCOONS AND GHOST CRABS ON CANAVERAL NATIONAL SEASHORE, FL.
- Creator
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Brown, Justin, Roth, James, University of Central Florida
- Abstract / Description
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Changes in abundance of interactive species can have cascading, community-wide effects (Soulé et al. 2003). Raccoons (Procyon lotor) prey on a competitor for marine turtle eggs, the Atlantic ghost crab (Ocypode quadrata). Conservation of marine turtles often includes managing raccoons--the most obvious egg predator--which may have broader ecological effects, and unknown effects on egg predation. Neither the relationship between raccoons and ghost crab density nor the effects of ghost...
Show moreChanges in abundance of interactive species can have cascading, community-wide effects (Soulé et al. 2003). Raccoons (Procyon lotor) prey on a competitor for marine turtle eggs, the Atlantic ghost crab (Ocypode quadrata). Conservation of marine turtles often includes managing raccoons--the most obvious egg predator--which may have broader ecological effects, and unknown effects on egg predation. Neither the relationship between raccoons and ghost crab density nor the effects of ghost crab density on egg predation are well understood. I studied raccoon-ghost crab interactions and the effects of environmental variation on their activity during the 2007 marine turtle nesting season on Canaveral National Seashore, FL. My goal was to model predator activity and identify efficient management strategies to reduce egg predation. Raccoon activity increased with increasing habitat diversity and edge of the dominant cover type, coastal strand. Raccoon activity increased locally and became less variable near segments of beach accessed for human recreation, but activity was greater on undeveloped beach, where habitat diversity and edge were greater. Ghost crab density and size were primarily affected by sand characteristics and recreation but decreased with increasing raccoon activity in June, which may have contributed to sustained declines in ghost crab density. Hatching success of marine turtles decreased with increasing ghost crab egg predation, suggesting ghost crabs are an important cause of egg mortality and not merely scavengers on unhatched eggs. Egg predation by ghost crabs was unrelated to ghost crab density or size, likely a result of monitoring limitations, but raccoon activity increased with increasing egg predation by ghost crabs, supporting previous research and experimental evidence suggesting ghost crabs can facilitate secondary nest predation by raccoons. This indirect interaction has strong implications for marine turtle conservation, because its strength may increase with increasing ghost crab density, potentially negating the effects of raccoon removal.
Show less - Date Issued
- 2009
- Identifier
- CFE0002667, ucf:48235
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002667