Jumat, 30 Juni 2017


 Jakarta, June 30, 2017 (Antara) - The El Nino natural phenomenon, which has increased water temperatures in many coral reef regions across the globe between 2015 and 2018, has triggered coral bleaching in many countries, including in Australia's Great Barrier Reef and in Indonesia.
        The National Oceanic and Atmospheric Administration (NOAA) of the United States has even declared the environmental disaster as the longest and most widespread coral bleaching event in recorded history.
        In Indonesia, the first signs of bleaching were reported in April 2016, and El Niño has impacted Indonesian coral reefs since 2015, according to a report published on www.biogeosciences.net. 
   However, a team of researchers studying Indonesian corals found that it is not the increase in rising water temperatures that caused the recent die-off of most corals globally but rather the decreasing sea level.
        While conducting a census of coral biodiversity in the Bunaken National Park, located in the northwest tip of Sulawesi (Indonesia), in late Feb 2016, the researchers noticed widespread occurrences of dead massive corals. Similar surveys carried out in the springs of 2014 and 2015 found the corals to be alive and thriving.
        The clear link between mortality and sea level fall also calls for a refinement of the hierarchy of El Niño impacts and their consequences on coral reefs, the report stated.

        The El Nino Southern Oscillation (ENSO) is a periodic shift in the ocean atmosphere system in the tropical Pacific that impacts weather around the world. El Nino is characterized by unusually warm ocean temperatures in the central to eastern equatorial Pacific. It happens every 3 to 7 years (5 years on average) and typically lasts nine months to two years. It is associated with floods, droughts, and other global disturbances.
        The Indonesian Institute of Sciences (LIPI) recently confirmed that El Nino occurring during the period between 2015 and 2016 had caused widespread coral bleaching across the Indonesian waters.   
   The condition of coral reefs in the country had deteriorated slightly in late 2016, although it had improved steadily since 1993, Dirhamsyah, head of the Oceanography Research Center of LIPI, noted in early June 2017.
         He warned that coral bleaching might occur more frequently due to climate change and global warming.
        Other factors affecting the country's coral reefs include destructive fishing activities using explosives, water pollution, and development activities in the coastal areas.
         LIPI has released a report on the latest condition of Indonesian coral reefs in 2017.
         Based on data from verification and analyses conducted in 108 locations and 1,064 stations across the Indonesian waters, it is reported that 6.39 percent of the country's coral reefs are still in excellent condition, 23.40 percent in good condition, 35.06 percent in moderate condition, and 35.15 percent in bad condition.
        The measurement of the condition is based on the living coral reef coverage percentage: the excellent category has coverage of 76-100 percent; the good category has a coverage of 51-75 percent; the moderate has a coverage of 26-50 percent; and bad category has a coverage of 0-25 percent.
         Suharsono, a senior researcher at the LIPI Oceanography Research Center, explained that the Indonesian coral reefs extend from the Sabang waters in Indonesia's westernmost province of Aceh to the Merauke waters in the easternmost province of Papua. 
   The highest distribution concentration is in the central and eastern Indonesian waters, including the waters of Sulawesi, Papua, Nusa Tenggara, and Maluku, which is also called the coral triangle core.
        Based on the latest satellite imagery mapping, Indonesia's coral reefs are spread across an area of 25 thousand square kilometers, or around 10 percent of the world's coral reef measuring 284,300 square kilometers, and constitute about 34 percent of the coral reefs in the coral triangle region, spanning 73 thousand square kilometers, according to a report of COREMAP-CTI LIPI in 2016.ii
   "As the center of the world's coral triangle, Indonesia has the highest number of coral reef species on the planet,  569 species from 82 families and 15 tribes,  out of the total 845 coral reef species in the world," he revealed.ii
   He cited as an example that Indonesia has 94 species of Acropora corals (Acropora sp), or 70 percent of the 124 found across the world. Caribbean has only three species.
        With regard to the Fungiidae family, the world has 43 species, and 41 of them, or around 90 percent, are in Indonesia.
        Among endemic species of coral reefs found in Indonesia are Acropora suharsonoi, Isopora togeanensis, Acropora desalwi, Indophyllia macasserensis, and Euphyllia baliensis.
        Moreover, Indonesia has a limited distribution of coral reefs that are also found in the Indian and Pacific oceans, such as Acropora kasuarini, Acropora rudis, and Acropora turtuosa.
        Coral reefs are not just beautiful but also crucial for maintaining the food supply of millions of people living along the coast all over the world. ***4***

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