1,721,115 research outputs found
Species Richness Estimation As A Tool For Biodiversity Evaluation And Monitoring In Nature Reserves
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Long-term effects of climate and phosphorus fertilisation on serpentine vegetation
No full textThe long-term effects of phosphorus fertilisation and climate on serpentine plant communities in Tuscany, central Italy have been investigated by using data from a 12 year before-after control-impact (BACI) experiment. Using the point quadrat method, data on plant communities were collected in June of each year from 1994 to 2005 in eight 2 × 2 m plots, four fertilised with phosphorus and four used as controls. Climatic data were obtained from a nearby meteorological station and summarised in 24 variables. Phosphorus addition significantly affected vegetation cover of both vascular and cryptogamic vegetation but did not influence species richness. The effects on species composition were clear but not marked, and consisted in promoting the abundance of some species already present in the community but not leading to the colonisation of other species. Interannual climate differences affected vegetation cover in the fertilised plots but not in the control ones, while climate affected the species richness values of different/various life-forms in both groups of plots, with more evident effects in the fertilised one. The effects of climate on plant community composition were weak once both the variability among individual plots and the successional dynamics were subtracted from the variance in species composition
Le specie aliene vegetali nel sistema di aree protette della Provincia di Siena: dati quantitativi per il loro monitoraggio
No full textRelationships between vegetation and morphology in the Radicofani calanchi (southern Tuscany)
No full textThe vegetation of the calanchi of Radicofani (southern Tuscany) is described on the basis of 50 phytosociological relevés carried out in areas with uniform erosion. Twelve vegetation types were identified. The pioneer vegetation (Parapholido-Artemisietum cretaceae) was only found in extreme environments with severe erosion. Grasslands dominated by Elytrigia atherica and those dominated by Dactylis hispanica, Phalaris coerulescens and Hedysarum coronarium were associated with deposition area. Grasslands of Bromus erectus and those dominated by Brachypodium rupestre were found on several morphologies. Scrub communities at different stages of evolution were also recorded on different morphological types, whereas woods with Ulmus minor and woods dominated by Quercus pubescens and Q. cerris were recorded along impluvium lines and on original slops respectively. Pioneer coenoses linked to moist environments were found on valley floors
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