The current environmental concerns revolve around the ecological imbalance caused by the seaweed species Kappaphycus alvarezii in the Gulf of Mannar Marine National Park, off the coast of Tamil Nadu. Dead coral reefs, a crucial part of the marine ecosystem, have been observed near the uninhabited Kurusadai Island, primarily due to the introduction of this seaweed species for commercial cultivation.
Understanding Seaweed and Its Significance
Seaweed refers to various species of marine algae and plants that thrive in water bodies ranging from rivers to seas and oceans. These can be minuscule or large enough to create underwater forests. Predominantly found along shorelines worldwide, seaweed is a common dietary staple in Asian countries.
Seaweed is vital as it serves numerous ecological and economic advantages such as providing nutrition, promoting economic growth through its applicability in manufacturing, acting as bioindicators by absorbing surplus nutrients and heavy metals, supplying oxygen and nutrients to other marine life forms, among others.
Seaweed Production in India
In 2021, India cultivated approximately 34,000 tonnes of seaweed, with the central government allocating Rs 600 crore to increase production to 11.85 million tonnes by 2025. Currently, around 750 farmers are engaged in seaweed farming, primarily focusing on cultivating Kappaphycus. Regions in Tamil Nadu, such as Ramanathapuram, are active in seaweed farming, and the future growth of this industry includes plans for a dedicated seaweed park in the state.
The Impact of Kappaphycus alvarezii Seaweed
Despite its benefits, the Kappaphycus alvarezii seaweed has proven harmful as it has pervaded six out of the 21 islands of the Gulf of Mannar Marine National Park, causing significant damage to local coral reefs. The International Union for Conservation of Nature lists Kappaphycus alvarezii as one of the world’s 100 most invasive species, and its adverse effects are noticeable in various parts of the world such as Hawaii, Venezuela, Tanzania, Panama, and Costa Rica.
Gulf of Mannar: An Ecological Overview
Situated between southeastern India and western Sri Lanka, the Gulf of Mannar is an inlet of the Indian Ocean renowned for its pearl banks and sacred chank (a gastropod mollusk). This gulf is also home to the Gulf of Mannar Marine National Park, established in 1982 under the Wildlife (Protection) Act, 1972. The park encompasses a wide variety of ecosystems including coral reefs, mangroves, mudflats, creaks, seagrasses, seaweeds, estuaries, sandy strands and saline grasslands, marshy areas, and rocky shores.
Corals: Their Importance and Threats
Corals play a crucial role in providing habitat for marine life, shielding against storms, and supporting livelihoods through fisheries and tourism. However, their existence is threatened by the invasive Kappaphycus alvarezii seaweed species, posing a significant challenge to the delicate ecosystem of the Gulf of Mannar Marine National Park.
Exam Context
Understanding the importance and threats posed to coral reefs is essential, as evidenced by relevant questions in the UPSC Civil Services Examination. In recent years, questions have focused on topics related to Bioreock technology used in the restoration of damaged coral reefs, symbiotic relationships of different species, the global distribution of coral reefs, and the impact of global warming on the coral life system.
