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The grasslands dominated by Bromus erectus and/or Brachypodium rupestre cover large areas on sandstone and marl-clay-sandstone substrata (limestone is excluded), of the Apennines and pre-Apennines between Pistoia and Arezzo provinces (Tuscany, Central Italy). Our investigation was focused on to 71 unpublished relevés and 45 literature relevés from Tuscany and surrounding areas, reporting the original relevés of Astragalo monspessulani-Brometum erecti, Centaureo bracteatae-Brometum erecti and Ononido masquillerii-Brometum erecti. The relevés were submitted to exploratory multivariate analysis, allowing to detect nine distinct groups. Their consistence was verified by mean of NMDS against Ellenberg/Pignatti indicator values, and CCA constrained against chorotypes and growth forms. Diagnostic species of the definitive groups resulting from the analysis were chosen according to species fidelity, based on the φ coefficient of association. The analysis splits the data set in two main subclusters; the first one (A) includes few relevés of low altitude, thermophilous conenoses, interpreted as a transition between the submediterranean aspects of Festuco-Brometea class and other Mediterranean herbaceous and shrubby classes; the second subcluster (B) includes most of the data set and can be clearly subdivided in pioneering, mesoxerophilous communities (B1 and B2a groups) and mesophilous communities (B2b group). The relevés of clusters B1 and B2a are referred to Coronillo minimae-Astragaletum monspessulanii association and to three other groups: Plantago argentea-Carex caryophyllea communities, Tragopogon samaritani-Bromus erectus communities, Festuco trachyphyllae-Brometum erecti ass. nova. The mesophilous group (B2b) includes the original Centaureo bracteatae-Brometum erecti and Ononido masquillerii-Brometum erecti relevés, together with a slightly differentiated community; due to the non-relevant differences between these grassland types from floristic, ecological and chorological perspectives, we propose herewith to treat them as three subassociations of Centaureo bracteatae-Brometum erecti (typicum, ononidetosum masquillerii and linetosum cathartici). Post-cultural grasslands in human-disturbed areas were also detected. All these communities can be attributed to Polygalo mediterraneae-Bromenion erecti suballiance (Bromion alliance), even if a clear subdivision between the mesoxerophilous pioneer aspects and the more mesophilous and evolved ones can be noted. IzvlečekTravišča v katerih prevladujeta vrsti Bromus erectus in/ali Brachypodium rupestre pokrivajo velike površine na podlagi iz peščenjaka in laporasto-glinastega peščenjaka (apnenec je izključen) na Apeninih in območju pred njimi med provincama Pistoia in Arezzo (Toskana, srednja Italija). Naša raziskava je bila osredotočena na 71 neobjavljenih in 45 objavljenih vegetacijskih popisov iz Toskane in sosednjih območij. Originalni popisi opisujejo asociacije Astragalo monspessulani-Brometum erecti, Centaureo bracteatae-Brometum erecti in Ononido masquillerii-Brometum...

Invasive alien plants are a major threat to biodiversity and they contribute to the unfavourable conservation status of habitats of interest to the European Community. In order to favour implementation of European Union Regulation no. 1143/2014 on invasive alien species, the Italian Society of Vegetation Science carried out a large survey led by a task force of 49 contributors with expertise in vegetation across all the Italian administrative regions. The survey summed up the knowledge on impact mechanisms of invasive alien plants in Italy and their outcomes on plant communities and the EU habitats of Community Interest, in accordance with Directive no. 92/ 43/EEC. The survey covered 241 alien plant species reported as having deleterious ecological impacts. The data collected illustrate the current state of the art, highlight the main gaps in knowledge, and suggest topics to be further investigated. In particular, the survey underlined competition as being the main mechanism of ecological impact on plant communities and Natura 2000 habitats. Of the 241 species, only Ailanthus altissima was found to exert an ecological impact on plant communities and Natura 2000 habitats in all Italian regions; while a further 20 species impact up to ten out of the 20 Italian administrative regions. Our data indicate that 84 out of 132 Natura 2000 Habitats (64%) are subjected to some degree of impact by invasive alien plants. Freshwater habitats and natural and semi-natural grassland formations were impacted by the highest number of alien species, followed by coastal sand dunes and inland dunes, and forests. Although not exhaustive, this research is the first example of nationwide evaluation of the ecological impacts of invasive alien plants on plant communities and Natura 2000 Habitats.

The effects of productivity on the parameters of the species–area curve were investigated in this paper using two data sets on terrestrial plant communities: (1) one including 48 plots in 12 experimental sites on ploughed, formerly cultivated fields in the Siena region, Italy, and (2) one including 40 plots in hay meadows in the Bremen region, Germany. In both regions, species presence of vascular plants was recorded in nested plots ranging in size from 0.004 to 256 m2 and 0.001 to 1000 m2, respectively. Productivity was estimated as dry standing biomass. In the Siena data set, species richness showed a humped-back relation to biomass in the plot sizes up to 1 m2. For the larger plot sizes, no significant correlations were found. In the Bremen data set, positive relation between species number and biomass was observed at the smallest spatial scale (0.001 m2), whereas the relation disappeared or tended to be negative for the larger plot sizes. In general, the slopes z of the log species–log area curves (SAC) were negatively related to biomass in both data sets, while the intercept c increased with biomass in the Siena data set and was unrelated to biomass in the Bremen data set. The relationship between c and z was negative in the Siena data set and positive in the Bremen data set. The above results differed somewhat depending on which plot sizes were considered for the calculation of the SAC. Literature data confirmed that there are no clear patterns in the inter-correlations between productivity, small scale and large scale species richness. Sites differing in productivity and in the slopes and intercepts of SAC may thus give rise to different species richness–productivity relationships. There can be one possible relation between species richness and biomass at one spatial scale (e.g. humped-back) and another type of relation, even opposite, at another spatial scale. This suggests that the properties of species–area curves do not respond in a uniform way to the changes in productivity, but depend on the type of habitat or plant community and its particular properties. The parameter of the SAC can then hardly be used as scale-independent parameter to investigate the effects of ecological factors, such as productivity, on species richness. The lack of clear patterns in the relations between small scale and large scale species richness implies that the predictions of the species-pool hypothesis may fail when applied to plot sizes as dealt with in this study

The shrublands growing on siliceous and/or calcium-poor substrata of the hilly and mountainous areas of north-western and central Italy were studied. This secondary vegetation is dominated by several acidophilous shrubs like Ulex europaeus, Cytisus scoparius, Erica arborea, E. scoparia and Calluna vulgaris. The synecology, synchorology and syntaxonomy of this vegetation was studied using multivariate methods, and discussed in comparison with similar types described in other zones of the Italian peninsula. Two new subassociations are proposed here: Erico arboreae-Arbutetum unedonis genistetosum germanicae and Calluno-Sarothamnetum ericetosum scopariae. Calluno-Sarothamnetum is typified; the Sarothamnion alliance is discussed and referred to Cytisetea scopario-striati. The presence of Calluno-Ulicetea and Cytisetea scopario-striati classes is discussed, and a syntaxonomical scheme is proposed.