La Grande barriera corallina australiana è seriamente in pericolo. A lanciare l'allarme giovedì è Terry Hughes, direttore dell'ARC Centre of Excellence for Coral Reef Studies, attraverso uno studio internazionale i cui risultati sono stati pubblicati sulla rivista Nature.
Gli esperti hanno studiato l'effetto di un'ondata di caldo marino del 2016, che ha causato lo sbiancamento e la morte di circa un terzo dei coralli esaminati. Dall'analisi dei dati raccolti, è emerso uno stretto legame fra la moria e le aree in cui l'esposizione al caldo è stata più estrema.
Il risultato è un "cambiamento radicale - si legge nel rapporto - nel mix di specie coralline in centinaia di banchi individuali. Comunità mature e diversificate si stanno trasformando in sistemi più degradati e rimangono solo le specie più resilienti".
Una realtà persa
Iscritta nel patrimonio mondiale dell'Unesco nel 1981, la Grande barriera si estende su una superficie di 348'000 chilometri quadrati, lungo la costa australiana nord-occidentale. Si tratta di una realtà particolarmente importante, se si considera che le barriere coralline coprono meno dello 0,2% della superficie oceanica e che ospitano il 30% delle specie animali e vegetali marine.
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