Sediment Dynamics and morphology data from Meinmahla Island, Ayeyarwady Delta, Myanmar

Abstract

Vegetated mid-channel islands play an important though poorly understood role in the sediment dynamics and morphology of tide-dominated deltas. Meinmahla Island is a mangrove-forest preserve at the mouth of the Bogale distributary, in the Ayeyarwady Delta, Myanmar. In this relatively unaltered environment, sediment dynamics can be directly connected to morphology. Field measurements of morphology, hydro- and sediment-dynamics from 2017–2019 provide insight into the fundamental processes governing the evolution of this mid-distributary island. Water depth, salinity, and turbidity were monitored semi-continuously, and velocity profilers with turbidity and salinity sensors were deployed seasonally in low-connectivity (dead-end) and high-connectivity (flow-through) tidal channels of the island. The morphologic evolution was evaluated using grain size, 210Pb geochronology in 1-m-long cores, remote sensing, and surveys of channel networks.