The water in the mangrove forest needs to refresh and be of good quality (salinity, dissolved oxygen, pH) in order for the mangroves and the organisms that are part of the mangrove habitat to flourish, like fish, sponges, anemones and mangrove oysters. The force behind the water circulation is the tidal flow; there is no river feeding the mangroves. The water moves through the roots as sheet flow, the channels and the lagoons. The growth of roots and accumulation of sediments reduce the capacity of the system to bring water in a timely fashion to all parts of the mangrove forest - especially the part farthest removed from the open ocean is most under stress.