Abstract:
River deltas, home to almost half a billion people around the world, are important coastal depositional systems. Valuable natural resources, fertile grounds, and convenient locations for trade have proven deltaic land to become hot spots for urbanization, industrialization, and food production over the last few decades. In this Dissertation the following research questions are investigated: (1) what remote sensing-based algorithms are most efficient in river delta shoreline detection? (2) what changes do we observe of shorelines of individual deltas historically? (3) how is human modification on river delta plains contributing to delta plain erosion? (4) are changes in fluvial sediment flux to the delta are directly linked to decadal changes in delta morphology? A novel multifaceted research approach is used that combines (1) remote sensing analysis of past delta morphology changes, (2) numerical modeling of fluvial sediment fluxes, and (3) GIS/Statistical analysis of shoreline migration rates to answer the intricacies of the aforesaid spatio-temporal questions. This study (a) provides recommendations on different shoreline extraction techniques and make the transfer of knowledge to lesser studied deltaic systems done informatively, (b) provides quantitative understandings of historical shoreline change rates of deltas, (c) quantitative understandings of delta plain erosion from humans having modified delta plains from their pristine conditions, and (d) how shoreline mobility is informed based on riverine fluvial sediment, overall, at a global scale. The outcomes of this study yield several novel insights and scientific advancements of delta morphology changes of the last four decades, and not only transforms our analytical capabilities for studying human influences on river deltas, globally, but also provide a predictive platform that could assist decision makers to make better informed decisions for long-term sustainability of deltas.
