Search results for " grasslands"
showing 10 items of 29 documents
Proposals for improvement of Annex I of Directive 92/43/ EEC: Central Italy
2021
The main purpose of the 92/43/EEC Habitats Directive is to contribute to the conservation of biodiversity, understood as habitat types and species of the flora and fauna of the European Union. To achieve this goal, natural and semi-natural biodiversity as a whole must be recognized and included in its annexes. As for the conservation of biotopes, named habitat types, Italy is unfortunately lacking as it the Annex I does not include important ecosystems that are typical of its territory, rare for biogeographical reasons or threatened. Therefore, the opportunity to identify a first list of significant habitats for central Italy is discussed here. For each of the new proposed types (new habita…
Floristic and phytosociological features of the Brachypodium rupestre communities in Italy
2018
The pale green dense Tor-grass (Brachypodium rupestre) tufts are a quite distinctive aspect of the Italian grassland pattern of the colline and submontane belts. B. rupestre is used to be found in secondary grasslands both in natural environments and in some aspects of the post-coltural environments such as forest clearances, abandoned terraced and extensive pastures. In northern Italy (Alps, Prealps and northern Apennines) B. rupestre has only sporadically been considered in the grasslands syntaxonomic frameworks. On the contrary it occurs in those regarding the central Italy where several semi-natural and post-coltural grassland associations (e.g. Polygalo flavescentis-Brachypodietum, Gal…
A phytosociological analysis of the Brachypodium rupestre (Host) Roem. & Schult. communities of Sicily.
2018
A phytosociological study on the Brachypodium rupestre grasslands in Sicily is presented. These grasslands form discontinuous secondary stands dynamically linked to the deciduous oak woods, which are widespread within the upper-colline, submontane and lower montane belts (800-1400 m) of the Tyrrhenian side of the northern Sicily and in the Sicani mountains. In the study area B. rupestre grasslands were mainly found in colluvial plains or drainage lines where relatively deep and mesic soils occur. In this paper 42 phytosociological relevés were performed and statistically analysed. Two new associations were described and classified in the alliance Polygalo mediterraneae-Bromion erecti (Brome…
Origin and evolution of the Mediterranean dry grasslands.
2007
In the Mediterranean region, three main structural types of dry grasslands can be recognized: those dominated by perennial caespitose grasses (wintergreen perennial dry grasslands, Lygeo-Stipetea), those dominated by thermoxerophilous therophytes (ephemeral dry grasslands, Tuberarietea guttatae), those dominated by chamaephytes, thistles and relatively small hemicryptophytes (summergreen perennial dry grasslands, Festuco-Brometea). All three kinds are commonly represented all over the Mediterranean territories, especially in the dry most areas. Relevant physiognomic, adaptive and floristic differences are featuring the three mentioned typologies. Lygeo-Stipetea and Festuco-Brometea may grad…
Low effective population sizes and limited connectivity inxerothermic beetles: implications for the conservation ofan endangered habita
2014
Fragmentation and isolation may have detrimental effects on the viability of populations. Xerothermic grasslands, which are extra-zonal analogues of steppes, are among Europe's most endangered natural environments. Information about connectivity between the remaining habitat patches is critical for effective conservation planning. However, very little is known about the actual levels of isolation of individual xerothermic patches at the inter-regional and local scale. In this study, 16 microsatellite loci were used to investigate genetic diversity, structuring, effective sizes (Ne), and connectivity among populations of the weevil Centricnemus leucogrammus at various geographic scales. Anal…
The Lygeo-Stipetea class in Sicily
2009
On the origin and evolution of the Mediterranean dry grasslands.
2006
A synthesis on the functional types of Mediterranean dry grasslands is outlined. Three different types are outlined: wintergreen perennial dry grasslands, wintergreen ephemeral dry grasslands, summergreen perennial dry grasslands. The first type is the most primitive, including several relict species, often characterized by very disjoint, sometimes anfi-saharian distribution ranges. The second type is resulting from an evolutionary trend towards short-lived life strategy, triggered by climatic and topographic perturbations that affected the Mediterranean region in the Plio- and Pleistocene. The third type, only marginally occurring in the Mediterranean region, is deriving from Holarctic and…
An “Uncertainty Principle” for the Mediterranean annual dry grasslands
2009
Preliminary results of diachronic researches on the spatial arrangement and species richness in Mediterranean annual dry grasslands (Tuberarietea guttatae) demonstrated that the patchiness resulted minimized and the temporal stability maximized at elevations offering the best compromise between the summer drought stress and the winter cold stress. Moreover, the temporal stability of the Mediterranean annul dry grasslands could not necessarily be related with their demographic inertia, meaning that the turnover and rearrangement of species within the community do not necessarily implicate significant changes in the average species composition over time. On the other hand, the survival chance…
Impressions from the 4th EDGG Research Expedition to Sicily: community composition and diversity of Mediterranean grasslands.
2012
Effects of temperatures on the spatial arrangement in Mediterranean annual dry grasslands
2009
Some preliminary results of diachronic researches on the spatial arrangement and species richness in Mediterranean annual dry grasslands belonging to the class Tuberarietea guttatae are presented. Our results are based on 12 permanent plots, set in three places at different heights in Southern and Central Sardinia. Sites were chosen to have annual species richness and plant density not significantly different. The relationship between patchiness and temporal stability was investigated at the scale of the square plots. We used the mean abundance divided by the SD in abundance (S = xm/r), as the measure of temporal stability of populations (Tilman 1999) and the Shannon-Wiener index to evaluat…