Seagrass beds can be found along the coast in many different regions. These beds are found in the shallows, where the grasses that grow there can get enough sunlight to produce the nutrients they need to grow and thrive.
Seagrass beds provide food and shelter for a number of different shellfish, fish and insects. They're also home to a number of other plants.
Seagrasses are - as the name suggests - the most recognizeable plants that grow in the seagrass beds along the coastal waters of the world. There are more than 50 different varieties of seagrasses, each one of which requires sunlight and nutrients in order to carry out photosynthesis, just like their land-locked cousins.
Because seagrasses require as much sunlight as those plants that grow on land, there is a limit to the depth at which they can take root. They also require high water clarity, and this makes them a good monitor of water pollution levels. Seagrasses help in keeping natural particles out of the water, as their roots trap sediment and sand particles. In doing so, seagrasses also help stabilize the sea floor by preventing erosion.
Seagrasses provide a nursery environment for many small fish and shellfish, as well as providing shelter from predators. Animals as large as manatees graze on the seagrasses.
Seagrass beds are excellent places for different types of macroalgae to attach themselves. There are a number of different types of macroalgae, which have no roots with which to attach themselves to the sea floor but can grow around seagrasses.
Because of their ability to carry out photosynthesis, macroalgae are excellent producers of oxygen and sugars. These sugars are, in turn, a food source for the many fish that make their home in the shelter of the seagrass beds. Macroalgae also remove phosphates and nitrates from the waters, helping to keep the water clear for other plants and animals.
Macroalgae come in a variety of colors, shapes and sizes. Different species include the halimeda, caulerpa and maiden's hair.
Diatoms are microscopic, single-celled plants that make up a large portion of both saltwater and freshwater marine life. They are one of the components of plankton, which is in turn one of the fundamental building blocks of marine life.
Like macroalgae, diatoms produce sugars as a byproduct of organic carbon fixation. This makes them another food source for the young fish and crustaceans that are born and raised in seagrass beds. As well as being a food source, they are also a major producer of oxygen.
Diatoms are either free-floating organisms, or can adhere to seagrasses and other permanent structures in the seagrass beds.
The fossil record states that diatoms have been around since at least the Lower Cretaceous period.