Research

River Deltas are predominantly coastal landforms that extend outward into the ocean. Over the past decades, they have experienced significant land loss due to anthropogenic activities such as subsurface fluid withdrawal and flood control structures. Coupled with climate warming, reduced sediment supply, and land subsidence, the rate of land loss is expected to accelerate in the future. To counteract the ongoing degradation of wetlands, sediment diversions–engineered channels designed to transport sediment-rich water to nourish inactive wetlands–have gained popularity. This nature-based solution aims to replicate natural delta-building processes; however, significant uncertainties remain due to gaps in our understanding of land-building mechanisms.

Under this theme, our research seeks to use process-based dynamics to unravel the fundamental mechanisms governing delta land-building processes. The knowledge learned from this research will provide us with insights for assessing wetland formation and long-term land sustainability.

Figure 1: Yellow River delta progradation through a summer of river flooding. In this 4 month period, the delta front moved forward more than 4 km and approximately 20 km² of new subaerial land was developed.

Group publications in this theme

1. Hariharan, J., Passalacqua, P., Xu, Z., Michael, H. A., Steel, E., Chadwick, A., Paola, C., & Moodie, A. J. (2022). Modeling the Dynamic Response of River Deltas to Sea-Level Rise Acceleration. Journal of Geophysical Research: Earth Surface, 127(9). doi: 10.1029/2022JF006762
2. Moodie, A. J., & Passalacqua, P. (2021). When does faulting-induced subsidence drive distributary network reorganization? Geophysical Research Letters, 48(22). doi: 10.1029/2021GL095053
3. Carlson, B. N., Nittrouer, J. A., Moodie, A. J., Kineke, G. C., Kumpf, L. L., Ma, H., Parsons, D. R., & Wang, H. (2020). Infilling Abandoned Deltaic Distributary Channels Through Landward Sediment Transport. Journal of Geophysical Research: Earth Surface, 125(2). doi: 10.1029/2019JF005254
4. Moodie, A. J., Nittrouer, J. A., Ma, H., Carlson, B. N., Chadwick, A. J., Lamb, M. P., & Parker, G. (2019). Modeling Deltaic Lobe-Building Cycles and Channel Avulsions for the Yellow River Delta, China. Journal of Geophysical Research: Earth Surface, 124(11), 2438–2462. doi: 10.1029/2019JF005220
5. Chadwick, A. J., Lamb, M. P., Moodie, A. J., Parker, G., & Nittrouer, J. A. (2019). Origin of a Preferential Avulsion Node on Lowland River Deltas. Geophysical Research Letters, 46(8), 4267–4277. doi: 10.1029/2019GL082491