Doctoral Dissertation Research: Roles of Tributaries, Floodplains, and the Anabranching Channels on Suspended Sediment Transport Patterns

University Of Texas At Austin, Austin TX

Investigators

Abstract

NATIONAL SCIENCE FOUNDATION GEOGRAPHY SPATIAL SCIENCES (GSS) PROGRAM ABSTRACT Large rivers play an important role in the transport of eroded materials, biogeochemical cycles, sustenance of complex ecosystems, biodiversity of their environments, and providing a variety of socio-economic services for humans. Despite their natural and economic importance, developing a fuller understanding of large river processes has been difficult because of the physical and mechanistic complexities of such processes. This doctoral dissertation research project will use innovative methods that include the integration of remotely sensed data with hydrogeomorphologic data to advance basic understanding of sediment distribution patterns in the complex fluvial environments associated with large rivers. The project will provide new insights into the morphodynamics of large rivers by characterizing the spatiotemporal patterns of sediment transport and identifying the hydrosedimentary interactions in channel floodplain systems. Project results will be useful for addressing a broad range of water resources management issues, wetlands preservation ecology problems, and local policy-making questions. The project also will strengthen institutional ties between U.S. and Brazilian universities and scientific centers, and it will incorporate educational outreach to local U.S. schools for support of underrepresented K-12 students in the science. As a Doctoral Dissertation Research Improvement award, this award also will provide support to enable a promising student to establish a strong independent research career. Because sediment plays a major role in the hydrophysical, ecological, and biogeochemical functions of any channel-floodplain system, the assessment of sediment transport and mapping of sedimentary environments over multi-temporal scales have been areas of focus for river scientists across multiple disciplines. The doctoral student whose dissertation research will be supported by this award will focus on two core questions: (1) What are the spatiotemporal patterns of sediment transport at major confluences along an anabranching main river channel? (2) What are the sediment transport, deposition patterns, and sediment budgets in the floodplains? The student will answer these questions by conducting field surveys, geomorphic mapping, and in-situ sample collection at several sites along the Amazon River. He will integrate these field data with remote sensing-derived products to model and characterize the macroscale sediment transport mechanisms in the channel-floodplain systems of the river. Outcomes from this research project would be useful to a global understanding of riverine anabranching patterns as well as shedding new light on the morphodynamics and environmental mechanisms of large river systems around the world.