Biogeographia – The Journal of Integrative Biogeography

Citizen science projects are able to collect massive amounts of data engaging thousands of motivated volunteers. Moreover web-based communities are a powerful way to promote citizen involvement. This paper describes Acta Plantarum (www.actaplantarum.org), an open source project born in 2007, aiming at the study of spontaneous Italian flora and hosting one of the most popular floristic web-based communities in Italy. Participation in the project is free and takes place, upon registration, by posting pictures and contributions in a discussion forum. This represents the heart of the website together with IPFI (Index Plantarum Florae Italicae), a complete nomenclatural database of Italian flora species created to archive all the botanical information. Over the years, thanks to the participation of amateur botanists from all Italian regions, a relevant amount of floristic records has been accumulated in Acta Plantarum. A new utility now allows the retrieval of floristic records stored in the forum through automatic and semi-automatic functions. As of 30 June 2020, Acta Plantarum had 1,793 active members and 74,188 floristic records were automatically or manually extracted, covering about 70% of the specific and subspecific taxa occurring in Italy. An appropriate validation process ensures reliability of data that can be extremely useful to the general audience, policy makers, amateur and professional botanists. Acta Plantarum results confirm the fundamental role of amateurs to develop large floristic databases and to increase floristic knowledge both at local and national level.