Abstract
Habitat classification is a crucial point for legal and applied implications related to nature conservation in Europe. European Directives (Habitat, Inspire, NEC) impose a common nomenclatural equipment to set management practices and networks for biodiversity conservation. As for the protection of species nomenclatural question is almost limited to cases of taxonomic revision, in the case of habitats far been lacking an official and shared nomenclature with comparative descriptions of the units to protect or assess. A consistent habitat classification is today still controversial, affecting the rationale in species assessments, dynamics and, ultimately, nature conservation policies. A system hardly consistent with the need of a unifying product at the continental scale has therefore established. The CORINE Biotopes first, the revision of Palaearctic and EUNIS, and nomenclatures derived from them (in particular those of the habitats of Annex 1 of the Habitats Directive) have sought to meet precisely this need. Many countries rely on this nomenclature for the definition of habitats on national territories. Europe is setting up a review of EUNIS nomenclature in order to make it more consistent with both the territorial reality and the methodology innovations. In particular has emerged noticeable need to use large database to make descriptions more consistent. In this direction global initiatives for the organization of large databases (GIVD, GBIF and, in Europe, European Vegetation Archive) received institutional recognition entering as processing tools also in legal framework (see the “Review of EUNIS classification”, “The Red List of European Habitats” Project). The availability and use of larger databases covering larger areas has no merely quantitative advantages. It provides a solid basis for taxonomical consensus since it often considers the total range of the involved species and inevitably leads to a revision not only of taxonomy but also triggers a sound reassessment of their systematic. Our experience with the current, established classification procedures, points out, when applied to large vegetation databases (although restricted to the national level), their powerful synergism in reducing bias in syntaxonomy, producing a much more sound system of biogeographically consistent units. A federated database of about 19000 georeferenced relevés from vegetation databases “BVN/ISPRA” and “GVD/La Sapienza”, participates in these initiatives. Applications that see already implicated the data contained in the archive aim to: formulate a EUNIS classification and mapping valid nationwide from field data also by integrating all available information at site (environmental parameters) and species (functional traits) level; develop niche models and predictive maps associated, to assess the resilience of species and communities to pollution related global changes. The goal is to identify procedures and protocols integrated to support institutional activities on the protection of biodiversity in different fields at both national and European scale.