1 and details about their development in Giosan et al , 2006a and

1 and details about their development in Giosan et al., 2006a and Giosan et al., 2006b. Similar long term redistribution solutions requiring no direct intervention Pifithrin-�� mw of humans beyond the partial abandonment of some delta regions can also be envisioned for other wave-dominated deltas around the world and even for the current Balize lobe of the Mississippi. Our sediment flux investigations for the Danube delta included core-based sedimentation rates for depositional environments of the fluvial

part of the delta plain and chart-based sedimentation rates estimates for the deltaic coastal fringe. They provide a coherent large-scale analysis of the transition that Danube delta experienced from a natural to a human-controlled landscape. Akt inhibitor One major conclusion of our study may be applicable to other deltas: even if far-field anthropogenic controls such as dams are dominantly controlling how much sediment is reaching a delta, the trapping capacity of delta plains is so small in natural conditions that a slight tipping of the sediment partition balance toward the plain and away from the coastal fringe can significantly increase sedimentation rates to compete with the global acceleration of the sea level rise. We also provide a

comprehensive view on the natural evolution for the Danube delta coast leading to new conceptual ideas on how wave-dominated deltas or lobes develop and then decay. Although a majority of fluvial sediment reaches the coast, at some point in a delta’s life the finite character of that sediment source would become limiting. After that new lobe development would be contemporary with another lobe being abandoned. In those conditions, we highlight the crucial role that morphodynamic feedbacks

at the river mouth play in trapping sediment near the coast, thus, complementing the fluvial sedimentary input. Wave reworking during abandonment of such wave-dominated deltas or lobes would provide sediment downcoast but also result in the creation of transient barrier island/spit Anacetrapib systems. On the practical side, we suggest that a near-field engineering approach such as increased channelization may provide a simple solution that mimics and enhances natural processes, i.e., construction of a delta distributary network maximizing annual fluvial flooding, delta plain accretion, and minimization of delta coast erosion. However, the large deficit induced by damming affects the coastal fringe dramatically. Although the rates of erosion at human-relevant scale (i.e., decades) are relatively small compared to the scale of large deltas, in other deltas than Danube’s where infrastructure and/or population near the coast are substantial, hard engineering protection structures may be inevitable to slow down the coastal retreat.

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