Anche la Svizzera è minacciata dalle specie invasive che stanno mettendo a rischio la biodiversità. Ma anche la sicurezza alimentare. A lanciare l'allarme è il Consiglio mondiale della biodiversità, con un rapporto pubblicato lunedì.
"Il problema è sottovalutato", ha dichiarato Sven Bacher, ecologo dell'Università di Friburgo, uno degli 85 autori dello studio. Delle 37'000 specie alloctone presenti in tutto il mondo, circa 3'500 sono classificate come invasive. Esse sono state una delle principali cause dell'estinzione per il 60% delle 1'000 specie scomparse finora. Nel 16% dei casi sono state l'unico motivo.
Tra gli "invasori" che in Svizzera hanno fortemente modificato gli ecosistemi regionali, lo studio cita la cozza quagga, un mollusco originario del lago d'Aral, ormai ampiamente diffuso nei bacini elvetici (dal lago di Costanza al Ceresio).
Gli studiosi stimano a livello mondiale danni per 374 miliardi di franchi all'anno, visto l'impatto sull'agricoltura e sulla selvicoltura.
RG 07.00 del 21.11.22: il servizio di Maria Jannuzzi
RSI Svizzera 21.11.2022, 08:24
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