What is Seagrass

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"What is Seagrass"
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Seagrass and importance

Seagrasses are angiosperms and perform a wide spectrum of biological, physical, ecological, social and commercial functions in the marine environment.  Seagrass ecosystems play an important role in nutrient cycling and in the food web. Seagrass ecosystems provide nursery grounds for many commercial and recreational fish and crustacean species. These species find protection against predators and feed on epiphytes growing on seagrass and organic matter. Seagrass leaves act as a filter by allowing any sediments suspended in water to fallout into the seagrass meadow. Extensive root systems of seagrass stabilize sediments and prevent sediment movement. Well developed seagrass meadows reduce sand erosion and maintain high water quality. Further, seagrass ecosystems support biodiversity by providing support for diverse communities and perform ecosystem function such as, catchment-seagrass link, trophic subsidies, carbon storage and landscape ecology.

Seagrass ecosystems provide a diversity of ecosystem services which are difficult to quantify. Ecosystem services of seagrass are listed in the table below. If seagrass ecosystems are damaged, ecosystem services get damaged and may not be adequately restored. Seagrass ecosystems are rich ecosystems, capable of providing a range of ecosystems functions, goods and services. According to the literature use values of seagrass ecosystems could be divided into direct-use values and indirect-use values. The direct-use values are based on conscious use of environmental assets in consumption and production activities. This category would include all the products derived from the natural resource either on or off site. This category also includes non-consumptive services such as recreation, tourism, research and education and aesthetic benefits provided by the presence of the natural resource. Seagrass ecosystems can be directly used as raw materials, cosmetics, fertilizer and handicrafts.

Indirect-use values are based on the contributions of natural resources to human life support. Their values derive from supporting or protecting economic values. As these contributions to human welfare is not marketed and are usually not rewarded financially, more difficult to evaluate. Storm buffering, sediment control, water quality improvements, nutrient cycling and organization of biodiversity are some examples of indirect-use values. Seagrass ecosystems improve the surrounding environment by purifying water and increasing off-shore fishery resources.

Non-use values involve no tangible current interaction (no production, consumption of life support linkages). These benefits are derived from information, knowledge that environmental asset exists for the individual concerned or others. Individuals do not need to use or intend to use the resource either directly or indirectly to derive values from the resource. Seagrass provides non-use economic values by enlarging aesthetic views and enriching cultural values.

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