title: Suitability of the ALien Biotic IndEX (ALEX) for assessing invasion of macroalgae across different Mediterranean habitats.
abstract: The ALien Biotic IndEX (ALEX) has been recently proposed to evaluate biological invasions in soft-bottom macro-invertebrate assemblages. The present paper proposes the use of ALEX in sessile assemblages of Mediterranean hard bottom habitats and tests it along gradients of invasion. For five invasive macroalgae a variable number of case studies per each of four habitats were examined from the available data sets. For each case study samples were attributed to four levels of invasion depending on the abundance of the invading macroalgae. Results showed that the application of ALEX to sessile assemblages of hard bottoms allows to qualify the level of invasion along the considered gradients. Moreover, the decline of index values matched the impact of invasion on species number of the assemblages. Results also suggest that the concurrent use of ALEX and indices of benthic quality status can be a valuable tool to assess biopollution in hard bottom habitats.
authors.affiliation: Dipartimento di Scienze della Natura e del Territorio, Università di Sassari, Via Piandanna 4, 07100 Sassari, Italy. Electronic address: lpiazzi@uniss.it.
authors.forename: Luigi
authors.initials: L
authors.lastname: Piazzi
authors.affiliation: Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA ex ICRAM), Roma, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Gennaro
authors.affiliation: Dipartimento di Scienze della Natura e del Territorio, Università di Sassari, Via Piandanna 4, 07100 Sassari, Italy.
authors.forename: Giulia
authors.initials: G
authors.lastname: Ceccherelli
mesh_terms: D000818:Animals; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods*; D058865:Introduced Species; D007558:Italy; D008522:Mediterranean Sea; D012624:Seaweed / Q000145:classification / Q000502:physiology*
keywords: Biological pollution; Ecological status; Hard bottom; Impact; Invasion; Macroalgae