L’anfibio cieco si adatta con successo alle sorgenti esterne mostrando condizioni fisiche migliori rispetto alle grotte
La ricerca appena pubblicata su Hydrobiologia da Springer Nature rappresenta una pietra miliare nella comprensione del comportamento ecologico del Proteus anguinus.
Lo studio condotto nel sistema carsico classico dell’Italia nord-orientale ha analizzato 76 esemplari attraverso tecniche di cattura-marcatura-ricattura per oltre quattro anni, comparando le condizioni di vita tra 40 sorgenti e 8 grotte.[1][2]
Metodologia innovativa per la biospeleologia italiana
Il team di ricerca, composto da Benedetta Barzaghi, Giorgio Grassi, Thomas Creanza, Magdalena Gajdošová, Veronica Zampieri, Stefano Lapadula, Matteo Galbiati, Gergely Balázs, Danilo Borgatti, Valentina Balestra, Valeria Messina, Edgardo Mauri, Gentile Francesco Ficetola e Raoul Manenti, ha implementato un approccio sperimentale senza precedenti nella biospeleologia italiana.
L’indagine ha utilizzato l’Indice di Massa Scalata (SMI) come parametro principale per valutare le condizioni corporee degli animali, una metodologia già consolidata per altri vertebrati acquatici ma mai applicata sistematicamente al Proteus anguinus.[3][4][5][1]
Gli esemplari catturati nelle sorgenti hanno mostrato un SMI significativamente superiore rispetto a quelli delle grotte, senza differenze significative nella frequenza di lesioni corporee.
Questa scoperta contraddice l’ipotesi che l’esposizione a habitat esterni comporti necessariamente maggiori rischi per questi anfibii specializzati.[6][3]
Biodiversità trofica e strategie adattive nelle sorgenti carsiche
La ricerca ha documentato una maggiore abbondanza e diversità trofica negli ambienti sorgentizi rispetto alle grotte.
Questi habitat di transizione, definiti ecotoni carsici, offrono risorse alimentari più abbondanti che compensano l’eventuale incremento del rischio di predazione.
Il comportamento di fedeltà al sito osservato negli individui monitrati suggerisce che il Proteus anguinus abbia sviluppato strategie comportamentali specifiche per sfruttare questi ambienti particolari.[7][8][1]
L’analisi della distribuzione spaziale ha rivelato che gli esemplari non utilizzano le sorgenti in modo casuale, bensì selezionano specificamente quelle con caratteristiche idroperiodiche favorevoli e minore presenza di predatori potenziali.
Questa selettività ambientale dimostra una plasticità ecologica precedentemente sottovalutata nella specie.[9][3]
Implicazioni per la conservazione degli stigobionti
I risultati confermano l’importanza ecologica critica delle sorgenti carsiche per la conservazione delle specie stgobiontiche.
Questi habitat non rappresentano semplici punti di emergenza idrica, ma veri e propri hotspot di biodiversità che supportano reti trofiche complesse e interazioni specifiche tra specie.
La scoperta evidenzia come gli ambienti di grotta e le sorgenti costituiscano un sistema ecologico integrato piuttosto che habitat separati.[10][11][1]
La ricerca fornisce inoltre elementi fondamentali per comprendere le risposte adattive del Proteus anguinus ai cambiamenti ambientali.
In un contesto di crescente pressione antropica sugli ecosistemi carsici, la capacità di utilizzare habitat alternativi potrebbe rappresentare un fattore cruciale per la sopravvivenza a lungo termine della specie.[12][13]
Prospettive future per la ricerca speleologica
Lo studio apre nuove prospettive per la biospeleologia italiana, suggerendo che molte specie sotterranee potrebbero avere ecologie più complesse di quanto precedentemente riconosciuto.
L’approccio metodologico sviluppato potrà essere applicato ad altre specie stgobiontiche per valutare l’importanza relativa di diversi tipi di habitat carsici.[7][10]
La ricerca evidenzia inoltre l’necessità di proteggere non solo le grotte ma l’intero sistema carsico, includendo le sorgenti e le zone di transizione.
Questa visione ecosistemica rappresenta un cambio di paradigma nella conservazione degli ambienti ipogei, passando dalla protezione di singole cavità alla salvaguardia di network ecologici complessi.[13][10]
Le implicazioni dello studio si estendono oltre la biologia del Proteus anguinus, fornendo un modello per comprendere come gli organismi specializzati possano adattarsi a gradienti ambientali estremi e sfruttare nicchie ecologiche apparentemente ostili.
Questa conoscenza risulta particolarmente rilevante nell’attuale scenario di cambiamenti climatici e alterazioni ambientali che interessano gli ecosistemi carsici europei.[11][13]
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