Temperature - Estuaries
Another important variable is temperature. The temperature of estuary keeps on fluctuating it heats up and cools down more rapidly under prevailing atmospheric conditions. Another reason for this variation is fresh water input. Temperature also varies vertically. The surface waters have the greatest temperature range and the deeper waters the smallest.
All the variation i.e. the salinity the texture of substrate, temperature, organic matter content and available oxygen is controlled by wave action and currents. The wave action in the estuaries is small. As a result there is deposition of fine sediments and development of rooted plants.