The purpose of this study was to collect baseline data of juvenile scleractinian coral density, spatial variability, size variability, and species composition across the linear shore parallel hard bottom coral communities offshore Broward County, Florida. Adult coral population data was also collected and compared with that of the juvenile coral population to better understand the local coral demographics and potential factors that influence the population structure. The juvenile and adult coral data from the Broward County coral communities was then compared to a second study region 50 kilometers south to identify latitudinal changes in the coral population structure. The results of this study found that the densities and the list of coral species observed within the Broward County study region did fall within the range of densities found in other studies completed along the southern portion of the Florida Reef Tract and the Caribbean. Despite having similar species richness to other Caribbean studies, there was an overwhelming dominance of only a few species. This was also found in the adult coral population in the Broward study region. The densities of both the juvenile and adult coral populations were significantly positively correlated as well as their number of species observed across the sites in the Broward County study region. Additionally, the highly dominant species found in the juvenile population were in the adult population. Despite increasing coral density and diversity with decreasing latitude found in other studies conducted along the Florida Reef Tract, the results from this study were not as clear. Density of corals and the number of coral species did increase from north to south on the Outer reef however there was a significant decrease in the depth of the sample sites. On the Pavement habitat the density of juvenile corals increased from north to south however the number of coral species did not increase. The density and number of species of adult corals did not increase on the Pavement habitat with decreasing latitude as well making the results unclear.

No description available.

Coral reefs are important to sustain marine ecosystems and provide a reliable resource for studying past climate. Corals are increasingly challenged by changing environments. The marginal corals of Hong Kong provide a natural laboratory to study the combination of environmental conditions controlling coral distribution and growth. Salinity and pH were found to impact corals in studies of coral distribution, extension, and culture. Hong Kong corals have low extension rates (1.2-11.4 mm/yr) and do not colonize in areas of low in salinity and pH. Ten years of instrumental records showed extension related positively to summer salinity and dissolved oxygen. Winter seawater temperature was inversely related to extension, while chlorophyll a showed positive relationship in autumn and winter. Culture results show low salinity negatively impacted coral calcification, photosynthesis, and extension. Corals exhibited reduced growth, paling and bleached. In contrast, coral growth increased under high pCO2, but corals decalcified in dark indicating underlying mechanisms may be altering coral physiology. The boron isotope (δ11B) proxy in corals is able to reconstruct past seawater pH when the pH of the extracellular calcifying fluid (ECF) is considered. A pH offset (ΔpH) was recorded in reconstructed pHsw due to ion pumping to ensure the ECF is saturated with respect to aragonite. By incorporating carbon isotopes (δ13C) into the δ11B-ΔpH relationship, δ11B can be corrected to remove ECF processes and reconstruct seawater pH. Culture results indicated δ11Baxial from axial tip recorded pH similar to other studies while low salinity impacted δ11Bbasal at the base. The different relationship shown from the same colony within the same cultured conditions suggested vital effects with differing coral metabolisms. δ11Baxial and δ11Bbasal related to extension but insignificantly. The large isotopic offset between δ11Baxial and δ11Bbasal indicated different growth mechanisms could possibly affected boron incorporation. The δ11B variation within a coral colony suggested careful and precise sampling for pH reconstructions is important. / published_or_final_version / Earth Sciences / Doctoral / Doctor of Philosophy

Thesis (Ph. D.)--Oregon State University, 2007. / Printout. Includes bibliographical references. Also available on the World Wide Web.

The chemical constituents of organic extracts of two Formosan soft corals Sinularia leptoclados and Sinularia nanolobata were studied. Investigation on S. leptoclados has led to the isolation of eight norditerpenes (1-8), including four new compounds, scabrolide A (1), leptolide A (2), leptolide B (3), leptolide C (4) and four know compounds (5-8), (11, 12)-epileptolide (5), ineleganolide (6), (1R*,5R*,8R*,10S*,11S*)¡V11¡Vhydroxyl¡V1¡Visopropenyl¡V8¡Vmethyl¡V3,6¡Vdioxo¡V5,8¡Vepoxycyclotetradec¡V12¡Vene¡V10,12¡Vcarbolactone (7) and (1R*,5R*,8R*,10S*,11R*)¡V11¡Vhydroxyl¡V1¡Visopropenyl¡V8¡Vmethyl¡V3,6¡Vdioxo¡V5,8¡Vepoxycyclotetradec¡V12¡Vene¡V10,12¡Vcarbolactone (8). Also, investigation on the chemical constituents of S. nanolobata has led to the isolation of two new compounds (9-10), nanolobatallin A (9) and nanolobatallin B (10). The structures of the new metabolites were determined on the basis of spectroscopic analyses, including MS, IR, 1D and 2D NMR. The cytotoxicities of the isolates against the NUGC, HONE-1, KB and Hepa59T/VGH cancer cell lines were studies. Compounds 7, 8 and 10 showed moderate cytotoxicity against KB and Hepa59T/VGH cancer cell lines. Compound 9 exhibited moderate cytotoxicity against Hepa59T/VGH cancer cells.

Thesis (doctoral)--Tallinn Technical University, 2001. / Includes bibliographical references (p. 59-64).

No description available.

No description available.

Effects of variation in eutrophication and in Diadema antillarum densities (grazing pressure) on the abundance and life history characteristics of Favia fragum on seven reefs along the west coast of Barbados were investigated. Densities of D. antillarum were negatively correlated with eutrophication levels, and interpretations of their effects have been made simultaneously. Abundance of F. fragum was lower on more eutrophic reefs with lower D. antillarum densities. This may result from effects of eutrophication and of D. antillarum on algal cover on reefs. Macrophytic algae were more abundant, and crustose coralline algae less abundant, on eutrophic reefs with lower D. antillarum densities; and macrophytic algal cover was negatively correlated with crustose coralline algal cover across reefs. F. fragum abundance was positively correlated with crustose coralline algal cover, and F. fragum occurred less frequently on reef areas where macrophytic algae were abundant. High eutrophication and low D. antillarum density (grazing pressure) may therefore reduce F. fragum abundance by increasing the cover of macrophytic algae relative to crustose coralline algae on reefs. Neither planulation periodicity, colony fecundity, nor polyp fecundity in F. fragum differed at different eutrophication levels and D. antillarum densities. Moreover, adult growth and adult mortality did not differ with eutrophication levels and D. antillarum densities on reefs. However, growth of juveniles appeared slower and mortality higher on eutrophic reefs with low D. antillarum densities. Moreover, larvae of F. fragum preferred to settle on crustose coralline algae than on turf algae (macrophytic algae), and the former are comparatively scarce on eutrophic reefs with low D. antillarum densities. The results suggest that the negative correlation between adult abundance of F. fragum and eutrophication levels/grazing pressure (D. antillarum densities) on Barbados reefs are caused primarily by effects

Thesis (Ph.D.) -- McMaster University, 1998. / Includes bibliographical references (leaves 148-150). Also available via World Wide Web.