Le terre emerse, percorse da innumerevoli strade, sono eccessivamente spezzettate e offrono aree troppo piccole per sostenere la presenza di fauna selvatica e biodiversità. È quanto emerge da uno studio pubblicato venerdì 16 sulla rivista Science, e ripreso da National Geographic.
Sebbene le aree senza strade costituiscano l'80% della superficie terrestre, queste sono divise in 600'000 pezzi, di cui oltre la metà ha un'estensione inferiore al chilometro quadrato. L'80% dei 'lotti' è grande meno di 5 chilometri quadrati, mentre solo il 7% supera i 100.
Tra gli impatti associati alla presenza di strade, gli esperti evidenziano deforestazione e frammentazione di habitat, aumento della mortalità della fauna selvatica, inquinamento chimico e acustico. Questi impatti, avvertono, in futuro potrebbero interessare una porzione più ampia del Pianeta, poiché una parte consistente delle superfici libere da strade non ricade in aree protette.
In base a un altro studio, pubblicato sulla rivista Plos Biology, da qui al 2050 nel mondo verranno costruiti altri 25 milioni di chilometri di strade. Per questo gli scienziati hanno creato un sistema di mappature che mostra le aree più idonee a ospitarle.
ANSA/Dek
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