• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 48
  • Tagged with
  • 50
  • 50
  • 15
  • 14
  • 13
  • 12
  • 11
  • 11
  • 10
  • 10
  • 9
  • 9
  • 8
  • 8
  • 7
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A preliminary report on the ecology of plants and animals of the St. Marks wildlife refuge.

Stevens, Rollin R. Unknown Date (has links)
No description available.
2

Influence of Soil Disturbance and Fire on the Distribution of Caesar’s Weed (Urena Lobata) in Pine Flatwoods

Unknown Date (has links)
Novel disturbances can increase the vulnerability of pine flatwoods to exotic species such as Caesar’s weed (Urena lobata), a plant that has invaded many ecosystems. To understand Caesar’s weed response to disturbance, a factorial field manipulation was used to quantify invasion success. Influence of feral swine (Sus scrofa) on the presence of seeds in the area was analyzed. The effect of heat on Caesar’s weed germination was also quantified. A winter fire and mechanical soil disturbance had no statistical effect on the spread of Caesar’s weed. However, in feral swine disturbed soils Caesar’s weed was more likely to be husked and experience less competition from seeds of other species. Low levels of seed heating increased germination. This data can provide information about the influences of fire and soil disturbances on the spread of Caesar’s weed, as well as how fire intensity levels can affect the spread of invasive Caesar’s weed. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection
3

Development and application of a new comprehensive image-based classification scheme for coastal and benthic environments along the southeast Florida continental shelf

Unknown Date (has links)
The coastal (terrestrial) and benthic environments along the southeast Florida continental shelf show a unique biophysical succession of marine features from a highly urbanized, developed coastal region in the north (i.e. northern Miami-Dade County) to a protective marine sanctuary in the southeast (i.e. Florida Keys National Marine Sanctuary). However, the establishment of a standard bio-geomorphological classification scheme for this area of coastal and benthic environments is lacking. The purpose of this study was to test the hypothesis and answer the research question of whether new parameters of integrating geomorphological components with dominant biological covers could be developed and applied across multiple remote sensing platforms for an innovative way to identify, interpret, and classify diverse coastal and benthic environments along the southeast Florida continental shelf. An ordered, manageable hierarchical classification scheme was developed to incorporate the categories of Physiographic Realm, Morphodynamic Zone, Geoform, Landform, Dominant Surface Sediment, and Dominant Biological Cover. Six different remote sensing platforms (i.e. five multi-spectral satellite image sensors and one high-resolution aerial orthoimagery) were acquired, delineated according to the new classification scheme, and compared to determine optimal formats for classifying the study area. Cognitive digital classification at a nominal scale of 1:6000 proved to be more accurate than autoclassification programs and therefore used to differentiate coastal marine environments based on spectral reflectance characteristics, such as color, tone, saturation, pattern, and texture of the seafloor topology. In addition, attribute tables were created in conjugation with interpretations to quantify and compare the spatial relationships between classificatory units. IKONOS-2 satellite imagery was determined to be the optimal platform for applying the hierarchical classification scheme. However, each remote sensing platform had beneficial properties depending on research goals, logistical restrictions, and financial support. This study concluded that a new hierarchical comprehensive classification scheme for identifying coastal marine environments along the southeast Florida continental shelf could be achieved by integrating geomorphological features with biological coverages. This newly developed scheme, which can be applied across multiple remote sensing platforms with GIS software, establishes an innovative classification protocol to be used in future research studies. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
4

The distribution and dynamics of small mammals, reptiles and amphibians in a mosquito impounded salt landscape

Hite, Walter George 01 April 2001 (has links)
No description available.
5

Distribution and Diversity of Benthic Foraminifera Within the Nearshore Ridge Complex off Pompano Beach, Broward County, Florida.

Unknown Date (has links)
Benthic foraminifera are exceptional organisms with distinctive features that allow for interpretation of both past and present environmental conditions. Some benthic foraminifera are widely distributed while some are restricted to specific environments due to their way of life. Foraminiferal assemblages south of Biscayne Bay and north of Cape Canaveral have previously been investigated; however, a gap exists in data covering a transitional zone along the Florida coast between the tropical waters of the western Atlantic and the cooler coastal waters along the North American coast. The purpose of this study was to collect baseline data on the benthic foraminifera of the small marine environment off of Pompano Beach that falls within this zone. This environment has a very particular relict reef system that includes a near-shore ridge complex, the unique foraminiferal assemblage of which has not been documented. Thirteen rubble samples were collected from this near shore ridge complex between October 2013 and April 2015 from depths of 2.5m – 9m. Abundances and diversity indices were calculated, and multivariate analysis and SHEBI analysis carried out to summarize baseline data for the area. Substrate types and seasonal collections were compared with foraminiferal abundances to determine if benthic foraminifera diversity varied between the four substrate types found on the near-shore ridge and between wet and dry seasons in Florida. Results revealed a variation in abundances for both substrates and seasons with the dominant genera being Quinqueloculina, Laevipeneroplis, and Archaias. Multivariate analysis displayed dissimilarities between substrates colonized by corals and those that were uncolonized. Comparison of studies from surrounding areas revealed fewer, however similar, species and different dominant genera. Overall, this area has proven to be a different environment compared to surrounding coastal areas and merits further investigation. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
6

Diet and foraging ecology of diamondback terrapins (Malaclemys Terrapin) in south Florida

Unknown Date (has links)
Dietary resource use for diamondback terrapins (Malaclemys terrapins) in subtropical mangrove habitats in south Florida creeks and islands was examined to elucidate long-term individual foraging strategies. Fecal analysis revealed seven categories of food items with gastropods, crabs, and bivalves being the most dominant food items respectively. Non-metric multidimensional scaling revealed differences in habitat, but not terrapin size class. Stable isotope analysis confirmed the findings, identifying habitat and site differences in δ13C and δ15N values for both terrapins and their prey. Bi-plots of terrapin and potential prey δ 13C and δ 15N values revealed potential dietary sources previously undetermined by fecal analysis. Comparisons of scute and blood isotope data revealed significant differences in δ13C indicating potential shifts in either food resources and/or habitat use through the time period recorded in the scute tissue. These tissue comparisons represent a powerful tool for estimating long term foraging strategies for a key estuarine species. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
7

The Diversity and Abundance of the Benthic Macroinvertebrates in an Oligo-Mesotrophic Central Florida Lake

Spence, Jeffrey F. 01 April 1981 (has links) (PDF)
Benthic macroinvertebrates and physicochemical parameters were sampled monthly in Spring Lake, Florida from July, 1978, to June, 1979. Spring Lake is a slightly acidic, sand bottom lake located in the sandhill region of the Central Highlands. While submersed vegetation is not dense, the lake does contain an abundance of the endemic submersed plant Mayaca aubletii. The littoral zone is dominated by plants belonging to the genera Panicum, Nuphar, Hydrocotyle, Nymphaea, Satittaria, and Typha. The benthic macroinvertebrates collected consisted of 51 species; approximately 50 percent were in the family Chironomidae. The annual mean number of individuals was 947/m2. The mayfly Hexagenia munda Orlando was the most numerous species (18.4 percent of the annual mean); the Chironomidae was the most numerous family (31.6 percent of the annual mean). The annual mean value for the Simpson's Index was 0.25 while the annual mean value for the Shannon Index was 2.60.
8

Sea turtle nutrient inputs to dune vegetation : a stable isotope analysis

Plog, Laura Beth 01 January 2004 (has links)
No description available.
9

A habitat suitability model for wading birds in a large subtropical lake: linking hydrologic fluctuations and nesting

Unknown Date (has links)
Anthropogenic hydrologic alterations can affect the quality of lake littoral zone habitats for wading birds, such as the great egret (Ardea alba), snowy egret (Egretta thula), and white ibis (Eudocimus albus). One such lake in Florida, Lake Okeechobee, has experienced a marked decline in wading bird nesting since the 1970’s, concomitant with changes in lake level management. It’s hypothesized that a reduction in foraging habitat has led to the nesting decline; however, there is little quantitative evidence of this link. A habitat suitability model was developed for Lake Okeechobee wading birds that incorporate the spatial and temporal dynamics of environmental factors that affect wading bird foraging and tests whether foraging habitat is linked to numbers of nests. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
10

Postglacial expansion of Rhizophora Mangle l. In the Caribbean Sea and Florida

Unknown Date (has links)
The Last Glacial Maximum (LGM) was a period of massive range contraction for numerous taxa, including the water-dispersed mangrove species, Rhizophora mangle L. Following the LGM, R. mangle expanded poleward via propagule transport by ocean currents. In this study, we use microsatellite loci to characterize the genetic structure of nine R. mangle populations and compare potential expansion pathways that resulted in the colonization of the Florida peninsula and Caribbean islands. Results show comparatively greater genetic connectivity between the Caribbean mainland and Florida, a similar pattern between West Africa and Caribbean islands, and substantial admixture on the island of San Salvador, the Bahamas. We conclude that Florida and Caribbean island R. mangle populations were likely recolonized via different expansion pathways. Estimates of recent migration rates are low and populations are structured into three regions (Caribbean mainland, Caribbean islands, Florida). These findings provide insight for future management and conservation initiatives. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

Page generated in 0.0849 seconds