Water and Sediment Dynamics

The rise and fall of tides in waterways that snake through the forests is one of the most conspicuous features of mangrove ecosystems. The movements of water and sediment into and out of mangrove estuaries are facilitated by tides and, to a lesser extent, waves. Tidal and wave energy in any estuary constitutes an auxiliary energy subsidy; tides allow mangrove forests to store and pass on new fixed carbon and benefits animals adapted to make use of subsidized energy. Tides do the work of bringing nutrients, food, and sediments to mangroves and their food webs, as well as exporting waste products. This subsidy is an advantage in that organisms do not have to expend energy on these processes and can shunt more energy to grow and reproduce. For the most recent and exhaustive treatment of the role of physical processes in mangroves, I refer the reader to Mazda et al. (2007).