Consolata Siniscalco

Inventory of the non‐native flora of Italy

Abstract In this paper we present a comprehensive inventory of the non‐native vascular flora of Italy, which was produced within the project “A survey of the Italian non‐native flora”, funded by the Italian Ministry for the Environment. Previously published floristic accounts were the main source of information. Historical records were critically revised and integrated with recent literature, data from herbaria and some unpublished information, so as to obtain a complete, up‐to‐date catalogue of the non‐native vascular plant species that occur spontaneously in Italy. The inventory lists 1023 non‐native species and subspecies, which account for 13.4% of all the Italian flora. The Italian non‐native flora was divided, according to its residence time, into 103 archaeophytes and 920 neophytes. According to its current invasion status, it was classified into 437 casual (42.7% of all non‐native) and 524 established taxa, the latter being divided into 361 naturalized non‐invasive (35.3%) and 163 invasive taxa (15.9%). The inventory includes a group of 62 species (6.1%) that lack recent records (i.e. since 1950). By combining local expertise into a unified, nationwide scheme using a standardized method and terminology, the inventory provides the essential scientific basis for the development of plant invasion research and management in the country.

Vegetation dynamics and arbuscular mycorrhiza in old-field successions of the western Italian Alps

Abstract The relationships between vegetational and arbuscular mycorrhizal (AM) dynamics were investigated in an old-field succession in the western Italian Alps. Vegetation and AM colonization were determined in eight sites corresponding to different stages of successional dynamics: (a) a field under cultivation; (b) fields abandoned for 1, 2 and 3 years supporting ruderal vegetation; (c) grasslands; (d) shrublands; (e) early wood communities; (f) mature woods. AM colonization was evaluated on the roots of representative plants from each community. The data thus obtained, together with those from the literature, were then used to calculate the plant community mycorrhizal index. This index provides qualitative and quantitative information concerning the relative percentage of non-mycorrhizal, AM and ectomycorrhizal plant cover in an entire plant community. The AM inoculum potential of each site was also determined using a bait approach. Farming disturbance temporarily reduced soil infectivity. Non-mycorrhizal ruderal annuals dominated after 1 year abandonment and covered 90–100 % of the surface. After 2 or 3 years, a rapid change to AM-colonized competitive and competitive-ruderal perennials was observed. The increase in AM inoculum was associated with an increase in floristic richness and equitability in the community. AM were also dominant in the shrublands and early wood communities, but gave way to ectomycorrhizal species in the mature woods. The observed AM inoculum potentials are in accordance with these findings. The results of this study further emphasize the need to take into account AM infection in plans for the renaturalization of degraded areas.

Phenology and carbon dioxide source/sink strength of a subalpine grassland in response to an exceptionally short snow season

Changes in snow cover depth and duration predicted by climate change scenarios are expected to strongly affect high-altitude ecosystem processes. This study investigates the effect of an exceptionally short snow season on the phenology and carbon dioxide source/sink strength of a subalpine grassland. An earlier snowmelt of more than one month caused a considerable advancement (40 days) of the beginning of the carbon uptake period (CUP) and, together with a delayed establishment of the snow season in autumn, contributed to a two-month longer CUP. The combined effect of the shorter snow season and the extended CUP led to an increase of about 100% in annual carbon net uptake. Nevertheless, the unusual environmental conditions imposed by the early snowmelt led to changes in canopy structure and functioning, with a reduction of the carbon sequestration rate during the snow-free period.

Remote estimation of grassland gross primary production during extreme meteorological seasons

a b s t r a c t Different models driven by remotely sensed vegetation indexes (VIs) and incident photosynthetically active radiation (PAR) were developed to estimate gross primary production (GPP) in a subalpine grass- land equipped with an eddy covariance flux tower. Hyperspectral reflectance was collected using an automatic system designed for high temporal frequency acquisitions for three consecutive years, includ- ing one (2011) characterized by a strong reduction of the carbon sequestration rate during the vegetative season. Models based on remotely sensed and meteorological data were used to estimate GPP, and a cross-validation approach was used to compare the predictive capabilities of different model formula- tions. Vegetation indexes designed to be more sensitive to chlorophyll content explained most of the variability in GPP in the ecosystem investigated, characterized by a strong seasonal dynamic. Model performances improved when including also PARpotential defined as the maximal value of incident PAR under clear sky conditions in model formulations. Best performing models are based entirely on remotely sensed data. This finding could contribute to the development of methods for quantifying the temporal variation of GPP also on a broader scale using current and future satellite sensors.

The Relationship between Airborne Pollen Grains and Unusual Weather Conditions in Turin (Italy) in 1989, 1990 and 1991

Abstract A quantitative and qualitative study was made of the pollination patterns of 14 taxa of special significance for the atmosphere of Turin (northern Italy). Particular attention was paid to the years 1989, 1990 and 1991, since there were marked climatic abnormalities during this period, especially in the form of an increase in the mean temperature for February and March compared with the means for 1803–1988. The onset dates of the principal pollination period (PPP) and the thermal sums (T sums) for 1989–91, both from 1st January and over the 30 days prior to the onset of pollination, were compared with the corresponding data for 1984–1988, published in a previous study. The amount of pollen collected for each taxon in each year was calculated. In 1989–91, the dates for the onset of pollination were almost always earlier than in the years when temperatures lay within the mean range, although they were not always accompanied by constant T sum values close to those of 1984–88. In some cases, the T sum...

A pollen calendar from turin (1981–1988) with reference to geography and climate

Abstract This paper describes a pollen survey from Turin based on 25 taxa of interest. The survey took place between 1981 to 1988 recording pollen types and amounts. Pollen was collected using a Hirst spore trap. A pollen calendar was constructed using 10 day means: aerosporological data were then compared to the urban vegetation and flora. Pollen distribution was analysed in relation to temperature, calculated as the taxons yearly specific temperature sum. The situation in Turin was then compared to other central European and Mediterranean stations: results were found to be more comparable with the former.

Short-term signals of climate change in Italian summit vegetation: observations at two GLORIA sites

Abstract Short-term changes occurring in high mountain vegetation were analysed using the data from two Italian sites already part of the GLobal Observation Research Initiative in Alpine environments (GLORIA – central Apennines and southwestern Alps). The study focused on a set of floristic (endemics), structural (life forms) and ecological (thermic vegetation indicator) variables. Vegetation data were collected according to the GLORIA multi-summit standardized method during the last decade. The re-visitation revealed a moderate decrease in regional endemic flora and significant variations in structural and ecological parameters. The increase in caespitose hemicryptophytes in both sites, in suffruticose chamaephytes in the central Apennines and in rosette-forming hemicryptophytes in the southwestern Alps emerged, highlighting the rapid responses of the alpine vegetation to climate warming. The increase in perennial life forms is related with the expansion of graminoids and small woody plants. These life forms seem to be most suitable to face climate warming in Italian summits. The increase in the thermic vegetation indicator exceeds the mean European summits increment, and this is due to the expansion of thermophilic species. Short-term analyses with fine spatial and temporal resolutions are still necessary to improve our understanding concerning species behaviour in high-elevation ecosystems.

The relationship between vegetation and pollen deposition in soil and in biological traps

Abstract The patterns of pollen deposition in the upper layers of the soil and in biological traps (mosses and lichens) in relation to the widespread and well known vegetational types of the Alps is investigated. The communities studied are beach woods, pine woods (Pinus cembra, P. sylveslris) and alpine pastures. Quantitative correlations between the pollen spectra and the vegetation have been calculated and over, under and equi-represented species delimited. Since representativity differs, in some cases, from that recorded in the literature it is suggested that it would be useful to continue the study in order to improve our understanding of actual pollen deposition and, as a consequence, of the interpretation of fossil pollen data.

Indigenous microfungi and plants reduce soil nonylphenol contamination and stimulate resident microfungal communities

Nonylphenol, the most abundant environmental pollutant with endocrine disrupting activity, is also toxic to plants and microorganisms, but its actual impact in the field is unknown. In this study, diversity of culturable soil microfungal and plant communities was assessed in a disused industrial estate, at three sites featuring different nonylphenol pollution. Although soil microfungal assemblages varied widely among the sites, no significant correlation was found with point pollutant concentrations, thus suggesting indirect effects of soil contamination on microfungal assemblages. The potential of indigenous fungi and plants to remove nonylphenol was assessed in mesocosm experiments. Poplar plants and a fungal consortium consisting of the most abundant strains in the nonylphenol-polluted soil samples were tested alone or in combination for their ability to reduce, under greenhouse conditions, nonylphenol levels either in a sterile, artificially contaminated sand substrate, or in two non-sterile soils from the original industrial area. Introduction of indigenous fungi consistently reduced nonylphenol levels in all substrates, up to ca. 70% depletion, whereas introduction of the plant proved to be effective only with high initial pollutant levels. In native non-sterile soil, nonylphenol depletion following fungal inoculation correlated with biostimulation of indigenous fungi, suggesting positive interactions between introduced and resident fungi.

Systematic studies on some species of the genus Artemisia: biomolecular analysis

ABSTRACT The internal transcribed spacers (ITS) of the ribosomal DNA gene of 11 taxa of the genus Artemisia were sequenced and compared with other 14 species taken from GenBank. The aims of this study are to clarify phylogenetic relationships for 25 taxa within the genus Artemisia, and to highlight the phylogenetic position of some species of geobotanical interest from the Alps or from other European areas. The results support the monophyly of the genus Artemisia, and the presence of the five main clades, corresponding to the morphologically based sections, Absinthium, Artemisia, Seriphidium, Dracunculus and Tridentatae. Only A. annua and A. genipi are not classified in the section in which they were traditionally included: A. annua is assigned to Seriphidium and not Artemisia, and A. genipi to Absinthium and not Artemisia. The basal structure of the tree differed in the 45 equally parsimonious MP trees, and thus appeared as a polytomy in the consensus tree. This does not allow us to completely solve the relationships among the clades. The molecular data are complementary with the morphological and biogeographical information and all are essential to draw valid conclusions on the relative closeness of the various taxa.