1,720,970 research outputs found
Contribution to the knowledge of red algae (Rhodophyta) of some watercourses in Central Italy.
No full textA first study of the algal flora of the Tiber River basin (Italy)
No full textThe floristic composition and spatial distribution of algal communities in 97 stations in the Tiber River and its tributaries were studied. A total of 128 taxa were found, belonging mainly to the Chlorophyta, Bacillariophyta and Cyanophyta. Filamentous algae (Cladophora glomerata, Vaucheria geminata, Oedogonium sp. and Spirogyra spp.) were the most common and abundant species. Melosira varians, Cocconeis pediculus, Gomphonema olivaceum, Cyclotella meneghiniana, Fragilaria crotonensis, Leptolyngbya valderiana and several species of Oscillatoria were also widely distributed but they were not important in terms of biomass. Spatial variations of species richness were found, with the middle and upstream sections showing a wider range of taxa than the downstream sections. Chamaesiphon incrustans and Lemanea fluviatilis were found only in the upstream sections of some watercourses of the basin in fast-flowing, cool, well-oxygenated waters, while Stigeoclonium tenue and Ulva flexuosa was recorded exclusively in downstream sections with slow-flowing, warm and eutrophic waters
Temporal floristic variations as indicator of environmental changes in the Tiber River in Rome
No full textA comparison of the actual vascular flora of the Tiber in Rome with a similar floristic survey of the 1970s was carried out. Changes in species richness, floristic composition and structure occurred in the last 30 years were described and dynamics of
abundance of each species was estimated. The total number of species decreased from 604 in 1975–1981 to 501 till date. The composition of the Tiber flora has partially changed. There has been a decrease in therophytes on the riverbed and an increase in hydrophytes especially eutrophic ones. Most of
Mediterranean species and those associated with
undisturbed land have been replaced by widely distributed, ruderal and alien species, as human
influences have increased. The floristic variations
were used as indicator to evaluate the effect of human
impact on the development of site and to describe the main changes in river management and bank use occurred locally over the last decades
Le piante vascolari come biondicatori della qualità fluviale. S.It.E., 22-25 Settembre, Viterbo
No full textRisultati preliminari di uno studio sulla bioindicazione delle acque interne attraverso analisi comparative su macroinvertebrati e piante vascolari.“Indici Diatomee e Macrofite”,28/05/2005, Trento, Agenzia provinciale per la protezione dell’ambiente
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Comunità animali e vegetali e qualità delle acque: un contributo all’attuazione della Direttiva 2000/60/CE in Italia. Rapporto ISTISAN.ISSN 1123-3117, 06/37, N° 4.
No full textAnalisi ecologica delle diverse componenti macrofitiche come bioindicatori della qualità delle acque: applicazioni al bacino del Fiume Tevere
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