Wetland plants from archaeological sites of Ferrara and Argenta (Emilia-Romagna, N Italy)

In the context of the archaeobotanical studies aimed at palaeoecological reconstructions, archaeocarpological investigations play a relevant role because they can compensate for the lack of floristic information persisting at least until the 18th century AD when botanical collections started to be organized within herbaria (see Preston et al. 2004; Wolters et al. 2005). When well preserved, seeds and fruits (= s/f) can often be attributed to a specific or sometimes subspecific level. It is well known that wetlands contain palaeoecological archives that can provide accurate records of their own history (Muller et al. 2012). Wetlands are particularly suitable for preserving waterlogged s/f, a condition of optimal conservation which facilitates their identification. The city of Ferrara (10 m a.s.l.) grew up around a ford on the river Po about the 7th century AD and its territory, that include also Argenta, therefore has always been characterized by a relevant occurrence of water and wetlands. These deposits are characterized by widespread evidence of plants related to water, constituting a valuable archive to investigate habitats which currently have become very rare and threatened, if they have not completely disappeared. The term “wetland plant” is here adopted in the broadest sense to include all the plants occurring in permanently or seasonally wet environments. This paper aims to reveal the peculiarities of the medieval/rinascimental archaeocarpological floristic lists through a comparison with the flora currently in the area of Ferrara documented by Piccoli et al. (2014). The Ferrara checklists included historical floristic studies carried out over the last two centuries. ... As has already happened in case of deposits of the area of Modena (Bosi et al. 2015), also those of the area of Ferrara, although more markedly anthropogenic, provided significant information about biodiversity in the past with regard to the present one. There are some similarities between the species of wet environments of the two areas (e.g. Cicuta virosa, Baldellia ranuncoloides, Rumex hydrolaphatum, Cyperus flavescens), but in the area of Ferrara appear also different species (e.g. Isolepis setacea, Schoenoplectus supinus, Fimbrystilis annua). The carpological records reveal the previous presence of a taxon in a specific geographical area (Birks & Birks 2000). Highlighting the ecology of species we will be able to understand the possible causes explaining the presence or the demise of several taxa, considering also the palaeoecological reconstruction of the environment in which they have been found.