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The common reed die-back syndrome was formerly reported mostly in Central Europe and more recently in the Mediterranean basin. This study investigates a case of reed die-back in Central Italy through a Geographic Information System (GIS) diachronic survey and the analysis of macromorphological and ecological parameters. Data were recorded during field activities on ten plots randomly distributed according to two ecological statuses, permanently and temporarily flooded. Culm density, height and diameter, clumping habit, flowering head and dead apical bud number and rate were measured; for each plot, chemical parameters of sediments were analyzed. Information on interstitial waters for the flooded plots was also provided. Floristic-vegetational features of the reed-bed community such as the total vegetation cover, the species composition and abundance were estimated. Univariate and multivariate analyses were used to demonstrate differences between morphological traits of flooded and emerged stands and their relationships with the chemical features of sediment. Macromorphological traits differed according to the ecological status, with flooded stands showing patterns related to poor health status of Phragmites australis, such as high rates of clumping habit and dead apical bud rate, high culm density and, to a lesser extent, low culm diameter and flowering head rate. Sulfates were relatively abundant in the sediment of flooded stands and, together with some heavy metals, resulted in some of the mentioned traits. Our results showed a relationship between reed die-back and prolonged flooding and highlighted the potential role of some chemical parameters in affecting the growth of permanently flooded reeds. [ABSTRACT FROM AUTHOR]

We examined the concordance between vascular plants and macrofungi (grouped into trophic groups) in Mediterranean forest habitats (central Italy). Our goal was to test how consistently plant and fungi groups classify plots in a broadleaf deciduous forest dominated by Quercus cerris. Our hypothesis was that groups of plants can be used as surrogates for the classification of macrofungal communities. The test of concordance comprised two steps: (1) the plant species data sets were subjected to cluster analysis, to obtain three classifications based on presence of all plants, presence and frequency of only woody species; (2) Multiple Response Permutation Procedures (MRPP) was used to test the performance of each plant classification applied to the fungi data sets. Sample scores on the first PCA axis were used to investigate the relationships between compositional patterns. In the concordance analysis, the classification based on woody plants only provided better results than the classification obtained using both herbaceous and woody plants. Cross-tests gave the best results when the "woody plants" classification was applied to ectomycorrhizal fungi (EMF) and, to a certain extent, to humicolous saprotrophs (Sh). The ordination analysis suggested that the frequency of woody plants follows a similar spatial distribution to EMF and Sh fungal groups and is therefore expected to covariate along the same environmental gradients. Many EMF exhibit preferences for few (one or two) hosts. Significant associations were found among numerous EMF and woody plant species. Woody plants such as Sorbus domestica and Prunus spinosa appear to be associated with many EMF. The combination of a high frequency of Fraxinus oxycarpa and Quercus petraea seems to promote distinct assemblages of EMF and Sh fungi. Characteristic assemblages of fungi were found in association with certain tree and shrub combinations. [ABSTRACT FROM AUTHOR]

Landi, M. and Angiolini, C., 2015. Soil-plant relationships in Mediterranean salt marshes across dune-cultivated land gradient The relationships between soil factors and plant species were investigated in salt marshes on the west coast of central Italy along a dune-cultivated land gradient with similar topographic elevations. Plant community composition was quantified in three zones (marsh-dune border, central marsh, and marsh-cultivated land border) identified across the gradient. The results suggest that the distribution and variation in abundance 'performance' of plant species is mainly ruled by salinity and soil texture gradients (from sandy to silt-clay). Texture seemed to affect vegetation zonation in the marshes near sand dunes, since at the marsh-dune border the percentage of wind-blown sand increases. Variations in field capacity, total organic carbon, pH, and calcium carbonate did not appear to control the performance of plant species. Indications on the performance of six species are provided. Limbarda crithmoides increased with the amount of sand and was often located at the marsh-dune border. Elymus repens and Phragmites australis increased with decreasing salinity and were frequently found at marsh borders, however E. repens also increased with the amount of silt-clay. Sarcocornia fruticosa increased with salinity and silt-clay, while Halimione portulacoides increased with salinity and seemed less subject to changes in soil texture. Elymus pycnanthus increased with salinity and decreased with the amount of silt-clay, however, the ordination suggested that other factors may be determinant for this species. These species could be useful to map saline environments and to reconstruct an appropriate scenario in restoration projects of Mediterranean salt marshes. [ABSTRACT FROM AUTHOR]