Streams and Rivers – Definition
Rivers usually begin as small mountain or hill streams where steep gradients produce fast flowing water conditions where loose rocks and stones are formed by continuous erosion.
Pebbles and gravel accumulate in places but vegetation is scarce or non-existent.
Most streams are tributaries of rivers. Once the river reaches flatter lowland areas, water flow decreases, sediment is deposited and vegetation becomes increasingly frequent.
The lower reaches of rivers are tidal where conditions are heavily influenced by tides and fluctuating levels of salinity.
Reedbeds are present in places along the fringes of the river muddy banks are exposed at low tide.