Thesis (M.S.)--State University of New York at Binghamton, Geological Sciences & Environmental Studies Department, 2007. / Includes bibliographical references.

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Currently it is common practice to conduct the environmental analysis of river water on randomly collected samples. Since rivers are considered to be continuously mixing, these waters are assumed to be homogeneous and therefore, the samples representative. This sampling parameter study was established to test that assumption.Three proximal points were established on the White River at Muncie, Indiana and sampled daily for twenty-five days. The samples were monitored for twenty-one different constituents: Alkalinity, chloride, color, calcium hardness, magnesium hardness, total hardness, total iron, ammonia nitrogen, nitrate nitrogen, nitrite nitrogen, dissolved oxygen, pH, orthophosphate, total phosphate, specific conductance, sulfate, turbidity, and temperature, using the Hach DR/EL-2 water analysis kit.The results indicated that thorough mixing is present and that homogeneity does exist for some constituents. However, the data also indicate that for some constituents homogeneity within the river does not exist. The significance of sampling frequency and the correlation of some of the interrelated chemical changes which occurred during the study are also discussed.

During the past decades, the systematic investigation of the morphodynamics of meandering rivers mostly involved the theoreticalanalytical methodology. The development of analytical models enabled the definition of equilibrium conditions, stability and evolution of river meanders and to investigate the interaction between planform and bedform processes and mechanisms. In recent years the new branch of remote sensing applied to river morphodynamics has been constantly developing simultaneously to the rapid increase of computational and satellite resources. The remote sensing analysis xiii is nowadays employed in a wide range fields in geophysics; for this reason, the past years have seen the prolific development of numerous algorithms for remote sensing analysis. However, remote sensing of meandering river morphodynamics has not been consistently integrated with morphodynamic modelling so far. There is a lack of sophisticated algorithms for the extraction of extensive morphodynamic information from the available remotely sensed data; this gap prevented researchers from seeking systematic validation of analytical models to define their range of applicability, and to exploit their potential for improved insight on observations in real world meandering rivers. The evolutionary dynamics of the channel width, at local and bend scale, as well as the dynamics of bars in meandering rivers represent two major unsettled issues in our present understanding of river meandering dynamics. In this thesis I first provide a systematic methodology for the automated extraction of meandering river morphodynamic information from multitemporal, multispectral remotely sensed data, coded in the PyRIS software. Moreover, I develop an analytical model to investigate the long-term planform evolution of periodic sequences of meander bends incorporating spatio-temporal variations of channel curvature, width and slope. A first model component predicts the temporal evolution of the channel width and slope based on a novel treatment of the sediment continuity at the reach scale. A second model component is a fully analytical, evolutionary model of periodic meanders with spatially and temporally oscillating width accounting for nonlinear feedbacks in flow and sediment transport by means of a twoparameters perturbation approach. Application of the PyRIS software to several long reaches of freeflowing meandering rivers allows me to develop a consistent set of observations on the temporal and spatial evolution of channel width and curvature with unprecedented level of detail. Furthermore, model outcomes indicate that meander-averaged width and slope invariably decrease during meander development, and that the temporal adjustment of the hydraulic geometry is controlled by the ratio between the evolutionary timescales of planform and riverbed, quantified from the analyzed meandering rivers dataset. The nonlinear perturbation model indicates that width and curvature co-evolve according to a hysteretic behavior in time and predicts that the meander belt width dramatically decreases when the meander resonance threshold is crossed. The modelling approach predicts wider-at-bend meanders when the bank pull is dominant with respect to bar push, which in turn promotes meander bends that are wider at inflections. Analytical modeling and remote sensing analysis are mostly integrated through a statistical approach; bend-scale evolutionary analysis xiv of planform descriptors such as channel width, width oscillations and curvature in large pristine meandering rivers exhibit good agreement with the outcomes of the proposed analytical models. Finally, the integration between analytical modeling and remote sensing analysis allows me to identify the key processes controlling the interaction between migrating sediment bars and planform-driven steady point bars. The conditions for the formation of migrating bars in meandering rivers are mostly related to the production of sediment supply by the basin, contrarily to the widespread idea that meandering rivers exhibiting migrating bars typically display lower values of the channel curvature.

Seventeen species of chaetognaths belonging to nine genera and three families were recognized from the samples collected in estuaries of Tamshui River and Kaoping River from February 2003 to November 2003. In Tamshui River estuary, eleven species belonging to eight genera and three families were recorded, with the mean abundance of 807 ¡Ó 1154 ind./100m3, while in Kaoping River estuary, fourteen species belonging to nine genera and three families were identified, with the mean abundance of 1601 ¡Ó 2796 ind./100m3. The three most dominant species in both estuaries were Flaccisagitta enflata, Aidanosagitta crassa and A. neglecta, and together they comprised ¡Ö95¢Mof the total chaetognaths. The abundance of chaetognaths showed apparent seasonal changes, higher abundance in February in Tamshui River estuary and in May in Kaoping River estuary. The abundance of chaetognaths showed no significant correlation with temperature in both estuaries, but displayed higher relationships to salinity and copepods. The body length¡]BL¡^ of Flaccisagitta enflata showed significant seasonal and spatial differences, with larger in both February and May in Tamshui River estuary but only in May in Kaoping River estuary. Aidanosagitta crassa showed significantly larger in BL in February than in other months in Tamshui River estuary, but it was not in Kaoping River estuary. The stage I of chaetognaths dominated in this study area and occupied ¡Ö80¢Mof the total count. Other stages mostly presented in February in Tamshui River estuary and in May in Kaoping River estuary. Only Fl. enflata was found to have gut content, all copepods, in February and May. The estimated daily predation impact on the standing stock of copepods ( by number ) was insignificant, only ¡Õ1¢H in both estuaries.

The microbial diversity of branches of Kaoping River at Lao-Nong Basin with altitudes from 100-2204m and Nantzuhien Basin with altitudes from 100-654m were studied. We used combining methods of bacterial, chemical and biotechnological to explore microbial diversity at the two basins to provide a reference for the environmental ecology of Kapoing River. It is the foundation for practicable environmental care. The results show the following: (1) The temperature in Tianchin at Lao-Nong Basin was lower(16.3¢J) than the rest of sampling sites(22-28¢J). (2) The temperature in Minsheng at Nantzuhsien Basin is lower(21.5¢J)than the of sampling sites(24-33¢J); other factors such as pH value, total organic carbon, and total organic nitrogen, varied according to different locations. In the microbacterial composition quantitatively, among all microorganisms, the bacteria content was the highest. Each gram of soil contain about 106~109 CFU at Lao-Nong Basin and 105~109 CFU at Nantzuhsien Basin, where as others such as the contents of actinomycetes and fungi were lower. Using 16s rDNA DGGE (denaturing gradient gel electrophoresis)analysis, the soil bacterial community composition at the two basin districts had discoverd that the microbial diversites at Nantzuhsine Basin were more abundant than those at Lao-Nong Basin. In regard to seasonal changes, our data agreed with traditional data. In the warm season, the microbial content is higher, and the community composition is also more abundant. The weather change in a short time period, such as a rainstorm and a quick shift of temperature seriously affected the number of bacteria. When the rain pours steadily down, it caused some degree of drop in bacteria number. However, when the rain stop, the microbacterial content and community composition gradually retured to original forms.

Thesis--University of Wisconsin. / Vita. Photocopy of typescript. Ann Arbor, Mich. : University Microfilms International, 1977. -- 22 cm. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 821-835).

Thesis (M.A. in National Security Affairs)--Naval Postgraduate School, June 2003. / Thesis advisor(s): T.V. Paul, James Russel. Includes bibliographical references (p. 97-100). Also available online.