Thalassia testudinium

Thalassia testudinium

                

             Thalassia testudinium is the dominant sea grass in Southeast Florida, as well as the Florida gulf coast. It is known for the wider blades as compared to the shoal grass, and a functional root system. Several factors, such as temperature, salinity, and water depth can limit the distribution of this particular species. T. testudinium prefers water that is less turbid, and an area that sunlight can reach them to photosynthesize. Turtle grass are not adapted to being exposed out of water, but it is mostly found in shallow water. It is usually associated with patch reefs, where the grass is found in between the individual patches of coral.  With the patch reefs, the fish species within the reef can use the turtle grass as a food source at night. A lot of herbivory takes place in this habitat.

Since the turtle grass has an established root system, it is considered a plant, not a type of algae. In algae, air bladders are attached to a stipe, which is further attached to holdfast to anchor the algae to a hard substrate. The turtle grass does not have air bladders, or a hold fast. It has an established root to help adjust to the high wave action that can be present in some ecosystems. The turtle grass has evolved from land plants, and is a vascular plant because of this. When observing the turtle grass, the plant has leaves (blades), and can potentially have flowers for reproduction. The marine algae is not a vascular plant, and do not have leaves and flowers.   

Turtle grass can reproduce both vegetative and by sexual reproduction. 
on. The main propagative method is the increase in length of the rhizomes. It results in an increase in length of the sea grass bed. In the marine environment, the turtle grass is a flowering plant. Many of the turtle grass plants produce small flowers at the base of the leaves. Male and female flowers grow on separate plants. The seeds from the flowers are viviparous, and can start new patches of sea grass. But the main preferred reproduction method, is a form of asexual reproduction (vegetative).     

T. testudinium is used for a food source, and a main nesting area for fish. The turtle grass is the main source of food for the green sea turtle, hence the name “turtle grass,” and other herbivorous fish. The green sea turtle’s jaws are serrated to help the turtle easily chew this primary food source contributing to the herbivory in the area. Because this is an important food source it turns the turtle’s tissue green. It provides breeding grounds for a variety of fish to reproduce. T.testudinium is also a food source for grazing parrot fish that can be found on the reef, proving its importance to whole food web. If harvesting were to occur, this important part of the ecosystem would be lost, and it will have greater affects involving the many marine organisms.

                As a habitat, turtle grass offers food, shelter, and essential nursery areas to commercial, recreational species of fish, and countless invertebrates. It produces high biodiversity among juvenile fish because this habitat has less predators, and is used as a nursery. When turtle grass dies, they contribute to the detritus found in this habitat used by the bottom dwellers such as different species of crustaceans. T.testudinium provides more structure to the habitat compared to the sandy bottoms, providing more species diversity. Turtle grass is important to the food webs because it is primary producer in the ecosystem, if harvested the primary consumers will be affected. 

https://www.sms.si.edu/IRLSpec/Thalas_testud.htm
http://www.iucnredlist.org/details/173346/0
http://eol.org/pages/1089018/details