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The main objective of this study is an assessment of the potential of applying land use optimization methods for minimizing the sediment yield from catchments. The study area is the Siran watershed, a subwatershed of the Tarbela watershed in Pakistan which drains directly into the Tarbela reservoir. It has an area of 4Ub sq. miles and receives 47.82 inches annual average precipitation. The main land use practices on the Siran Watershed are agriculture, rangeland grazing and forestry. A stochastic model for simulating daily precipitation and another for simulating daily maximum temperatures are developed for the area. The synthetic daily precipitation events are transformed into daily streamflows by the soil moisture counting streamflow model using the synthetic daily maximum temperatures as input. The streamtlow model, called the Generalized Streamflow Simulation System, is modified and used for simulating baseflow recessions. The stochastic precipitation model, the stochastic temperature model and the deterministic streamflow models were combined with the deterministic sediment yield model for simulating sediment yield from the watershed. The modified Universal Soil Loss Equation was used for simulating sediment yield. Parameters at these models were determined from data taken on the Siran Watershed. A linear program was used for land use optimization to minimize sediment yield and maximize watershed production. Both optimization processes ended up with the same land use areas allocating the Maximum area for forests. The expected sediment yield was reduced by 2.5 times and production of watershed was doubled. Optimization of crops was accomplished by maximizing the production of agriculture lands. This resulted in the allocation of major agriculture land areas for apple orchards. By adopting the final optimized land use practices, the sediment yield can be reduced to half and watershed production can be increased six times. The results of the present study are encouraging and indicate that application of land use optimization methods for reducing sediment yields nave great potential on the study area and on other subwatersheds of the Tarbela and Manyla Watersheds. The methodology developed in this study can provide a useful tool for watershed managers to reduce sediment yields and increase the income of the local inhabitants by maximizing the agriculture production in other parts of the country.

On average, one percent of reservoir storage capacity is lost annually to sediment deposition in reservoirs. Several methods for sediment removal do exist, but most are inefficient and costly in terms of money or water usage. One method known as siphoning has been shown to adequately remove sediment, but present knowledge is lacking to optimize this method for removal. Three relationships for sediment transport in a pipe were compared against data collected from a physical model resembling a reservoir siphoning system. None of the three accurately predicted the physical model results. However, some trends among the relationships were observed, indicating that with additional modification to the relationships, parameters could possibly be developed to design a prototype system.

This dissertation presents the detailed results of investigations into the coastal geomorphological effects and sedimentation processes associated with a recent large tsunami event which took place on the 12th December 1992 in Flores, Indonesia, and the stratigraphical and sedimentological study of a widespread sand layer preserved in coastal sedimentary sequences along the eastern coast of Scotland representing a low-frequency, high-energy marine event, which took place at circa 7,000 radiocarbon years B.P. With modern alalogues, established in this dissertation, of both tsunami and storm surge sedimentary characteristics and sedimentation processes as the key, together with high-resolution sedimentological evidence obtained from the circa 7,000 radiocarbon years B. P. event, competing hypotheses of the likely causes of the marine flooding by either a tsunami or storm surge event are tested. It is concluded that the circa 7,000 B. P. marine flooding event was a tsunami, believed to have been generated by one of the world's largest submarine landslides in the Norwegian Sea - the Second Storegga Slide. The particle size composition of tsunami sediments is found to vary from well sorted to poorly sorted and is controlled by both the characteristics of the source sedement (local coastal sediments) and sedimentation processes associated with tsunami inundation. Tsunami sediments deposited on land are believed to form continuous and discontinuous sedimentary sheets ascending up to levels distinctively higher than contemporary sea levels and to contain a general landward-fining trend and multiple sets of grading (fining-upward) sequences, reflecting spatial changes in particle size composition. A conceptual model of coastal tsunami sedimentation is established including processes of seaward and landward sediment movements, episodic rapid deposition, sediment accumulation and erosion.

Thesis (M.Sc.)--University of Waikato, 2007. / Title from PDF cover (viewed March 18, 2008) Includes bibliographical references.

Thesis (doctoral)--Université de Rennes, 2004. / Includes bibliographical references (p. 197-209). Also available on the World Wide Web.

Thesis (M.S.)--University of North Carolina at Wilmington, 2004. / Includes bibliographical references (leaves : [75]-77).

Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 325-351). Available also in a digital version from Dissertation Abstracts.

Thesis (M.A.)--Miami University, Dept. of Geography, 2008. / Title from first page of PDF document. Includes bibliographical references (p. 44-49).