Seagrasses are found worldwide in shallow lagoons and are widely recognised as a valuable resource to both humans and the surrounding environments. In the Cayman Islands seagrasses are home to valuable fish and invertebrates, help keep waters clear and beautiful, stabilise local sediments, slow erosion of shorelines, and provide food to animals tourists like to see (or eat). Notable animals that make their homes in Cayman seagrasses include the green sea turtle, southern stingray, and queen conch.
All of the positive services seagrasses perform for humans and the environment are called ecosystem services. Dollar amounts are used to value ecosystem services because humans very often profit from the environment through harvest of fish, tourism, and real estate sales. In addition to value from fishing and tourism profit, the presence of seagrass environments can prevent the loss of assets during storms and preserve the value of a coastal property by helping water clarity and retaining sand.
Seagrasses are thought to rank among the top three most valuable habitats in terms of ecosystem services they provide. Unfortunately, seagrass cover worldwide is decreasing due to pollution, coastal development, disease, and general human disturbances such as boat propeller scars and dredging. As the importance of seagrass beds becomes more widely known the hope is that more protective regulations will be put in place for these areas in order to preserve the rich diversity, immense productivity, and natural shoreline protection they offer coastal areas across the globe.
Despite the obvious benefits of seagrass meadows they are one of the most understudied systems in the world. Current research at the Central Caribbean Marine Institute is focusing on seagrass meadows in the Cayman Islands in order to assess the growth of both seagrasses and calcifying algae in the shallow lagoons. Calcifying algae share habitat with seagrasses and are able to build calcium carbonate skeletons much like corals. Much of the sand in the Caribbean originated as algal tissue and thus calcifying algae are regarded as a very important part of the carbon cycle. The looming beast of ocean acidification (see What’s Hot March 2011 p94) on the horizon threatens the calcification process and will have unknown effects of seagrasses. Thus, protecting, understanding, and studying seagrass meadows in the context of global change is more important now than ever.
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