No description available.

Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Includes bibliographical references (p. 228-244).

No description available.

published_or_final_version / Botany / Doctoral / Doctor of Philosophy

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

Previous studies in the population genetics of the oyster drill Thais clavigera show that snails from the west coast of Taiwan belong to the same population. However, the genotype frequency of arginine kinase (Ark) in large snails is different among sites in the west coast. In general, changes of temperature and desiccation caused by tidal cycle are the most important twp environmental factors affect genetic variation of intertidal organisms. In the present study, the relationship between the frequency of Ark genotype and tide was evaluated through the following experiments. It has been found that the frequencies of Ark genotype of snails, collected in August with the size range of 25-35mm, were correlated to tides. A higher grequency of Ark63/100 (0.47~0.56) was in the upper intertidal and a higher frequency of Ark63/63 (0.49~0.66) was at the lower end. Moreover, the genotype frequency also varied with size, i.e. more Ark63/63 in small snails (<25mm) and more Ark63/100 in large snails (>35mm). Laboratory desiccative experiments indicated that snails with genotype of Ark63/100 preferred in the areas of high water level and Ark63/63 in areas of low water level. The laboratory results were consistent with the field data. To compare the enzyme activity, there was no difference among the genotypes of Ark63/63, Ark63/100 and Ark100/100at temperatures of 18, 24 and 30¢J. In summary, the frequencies of Ark genotype varied with tide and size and factors such as temperature, desiccation and reproduction may play important roles in the relationship.

This study investigates the variations of flow field and water mass due to the influence of topographic effect in the Kaoping Submarine Canyon. The data used in this study are collected from five cruises of field observations using research vessel OR3. Instruments deployed include ship-board ADCP¡BCTD¡Btow-ADCP, moored ADCP and vertical arrays of temperature loggers. The collected data are analyzed through a variety of time series analysis technique, such as harmonic analysis¡Blow-pass filter¡BFFT and EOF analysis. The results show that (1) the flow in the Kao-ping Canyon was dominated by semi-diurnal tide. Harmonic analysis shows that both bottom layer and the shelf region are dominated by the M2 tide. The amplitude increases with canyon depth, and the major axis of tidal current align with canyon orientation. (2) Water mass are moving around by the oscillation tidal current along the canyon. During flood, surface water flow to southeast, while bottom flow is up canyon. During ebb, surface water goes to northwest, while bottom flow is down canyon. (3) The low-pass flows indicate a counter-clockwise rotation from surface down, which is explained due to bottom frictional effect. (4) EOF analysis of CTD profiles suggested that the first mode (semi-diurnal tide) can explain 88% of the variations.

Thesis (M.S.) in Zoology--University of Maine, 2002. / Includes vita. Includes bibliographical references (leaves 51-57).

No description available.

Although sand deposits are present on many intertidal rocky shores, their effects on species richness, zonation and trophic structure have often been overlooked. This study is the first to recognise sand as an important abiotic factor on South African rocky shores. Rocky shores in the eastern Cape Province of South Africa are subject to extensive sand inundation and are composed of two hard substrata of differing topographies. Four sites on one substratum and six on the other were sampled quantitatively using quadrats. The biota were identified, counted and/ or weighed to provide a matrix of species biomass and numbers in separate zones. This matrix was then analysed using ordination and classification. A total of 321 species were identified which is more than local rocky or sandy shores. While the intermediate disturbance hypothesis would predict high species richness on these shores, it does not fully explain this richness nor the distribution of species assemblages. Habitat heterogeneity, including the dynamics of sand deposits, is strongly influenced by substratum topography and is the most important factor generating species richness. Abrasion by sand (sand scour) causes local reductions in richness but the presence of semi-permanent sand deposits allows habitation by psammophilic and sand-dependent species. As a result the biota of a sand inundated rocky shore includes both a full rocky shore and a large sandy beach component. Substratum topography controls patterns of sand deposition and retention and community analysis showed that samples were clustered primarily according to species richness and secondarily according to substratum type. Ordination of species identified an arc of species assemblages of decreasing levels of sand tolerance. These corresponded to sample groupings so that th assemblages found in various habitats were characterised by particular levels of sand tolerance. The presence of sand has a negative effect on the biomass of primary producers and filter feeders but a positive effect on the biomass of deposit feeders. Because sand is retained to different degrees in different zones, trophic structure varies between zones and to a lesser extent, between rock types. In general, however, the trophic structure of sand inundated rocky shores is similar to that of non-inundated shores.