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1.
Abstract

Vertical zonation of vegetation in Italy. – A revision of the scientific terms used by Italian botanists for the vertical zonation of vegetation reveals some inconsistencies and allows to propose an alignement with the nomenclature used in English and proposed already during the International Botanical Congress of 1910: Belt (ital.: fascia) for the topographical zonation and zone (ital.: zona) for the geographical zonation. Italy belongs to two zones: the mediterranean and the medioeuropean one. A scheme of vegetation belts in both of the zones is proposed. The indications subalpine and montane are substituted by boreal and subatlantic.  相似文献   

2.
Summary

Purpose of this paper is to point out the residues of Quercus Ilex woods in the hilly region of Murgia di Putignano (Puglia) which lies inside the distribution area of Q. trojana, now the main wood-forming tree-species of this territory.

Fourteen different small Q. Ilex stands are mentioned, as marked on alleged map. One of them (n° 1 on the map) has been more carefully studied through a whole year, and all plants growing in it have been collected.  相似文献   

3.
Summary

The Author has studied the vegetation of the Ossero pools (the large and the small one) analising especially the formation which are characteristic of them.

In the level partion of the large pool the following formations — starting from the beach — are to be noted: Salicornia herbacea L., Hordeum marinum Huds., Inula viscosa All. and Artemisia coerulescens L.

The Salicornia herbacea L. formation is sensibly homogencus in that portion of its area in which, owing to the high saline concentration of the soil, no other pecies is able to grow. In the remaining portion with a lower saline concentration, other species accompagny Salicornia herbacea.

The Hordeun marinum Huds. formation comprises that portion of the pool which, being but little above the sea level, is invaded by high tides during the winter time. The saline concentation of the soil is here lower than in the area of the Salicornia herbacea formation. On the sea side Hordeum marinum is mixed to Salicornia herbacea; on the opposite side it accompanies annual species with brief life cycle.

The Inula viscosa All. formation which is generally characteristic of the newly formed ground in the Ossero pound is only occasional and consequently unstable.

Last of all the Artemisia coerulescens formation is much more stable than that of Inula viscosa, although established in a ground of similar origin, but with a greater humus content.

Of special interest are two small lakes which are situated on the border of the large pool. Thir vegetation is composed by typically laky species.

The author compares the succession of formation described above with that of the other coast marsh in the mediterranean region, especially at Campora, Arbe (see Morton 1915).

Here is, however, the succession of formations not so regular as in the large pool of Ossero. Nevertheless, both Campora and Ossero are to be classified as « Formation des Meeresstrandes» (Morton).

Crypsis aculeata Ait., Hordeum marinum Huds., and Medicago litoralis Rohde found at Ossero were not known for the flora of Cherso.

The vegetation of the small pool at Ossero (which only rarely invaded by the sea water) does not show the regular succession of formations which is typical of the large pool it comprises two main groups of species, namely: 1) those living between the beach and the pool, and 2) those extending from the pool to the inland.

Some species present in the large pool (among them Crypsis aculeata, Hordeum marinum, Medicago litoralis) are not represented in the flora of the small pool and vice versa.  相似文献   

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Abstract

Vegetation of the ponds in the zone of Olbia (northeast Sardinia). – The present paper contains a study on the vegetation of the ponds and marshes in the neighbourhood of Olbia. The following well determined associations have been ascertained: Chaetomorpho-Ruppietum, Salicornietum fruticosae, Arthrocnemeto-Limoniastretum monopetali, Juncetum maritimi, Scirpetum maritimi, Caricetum divisae, Schoeneto-Plantaginetum crassifoliae. Furthermore, some other consociations have been observed (with: Pholiurus incurvas and Triglochin bulbosum; Juncus subulatus; Scirpus setaceus and Spergularia rubra; Agropyrum elongatum and Spartina juncea).

The authors have also taken into consideration the present distribution of the vegetation in relation to the modifications due to the fact that this area has been reclaimed.  相似文献   

7.
Abstract

On the use of characteristic specific combination to compare vegetational types. – A comparison between ordination and classification of phyto-sociological types using synthetic tables and characteristic specific combination of Raabe was made. The results of classification and ordination are very similar in both the cases, so that we can propose the characteristic specific combination of Raabe as a good method to limit the number of species when the vegetational types have to be classified.  相似文献   

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Abstract

Preliminary studies on the marine phythobenthic communities in the Straits of Sicily and adjacent islands. — The results of algological researches carried out by the Gruppo di Algologia of the S.B.I. in the Straits of Sicily and adjacent islands are reported. 288 species have been collected, 275 of which have been identified: 160 were Rhodophyta, 62 Phaeophyta, 32 Chlorophyta, 16 Cyanophyta and 2 Angiospermae. The vegetational research leads to the following conclusions: 1 - the harbour areas (Pantelleria, Malta: loc. 1 and 11) show a nitrophile vegetation, particulary near La Valletta where an almost pure population of Pterocladia pinnata is found; 2 - there are important biogeographical differences between Pelagie islands (Lampedusa, Linosa) and Pantelleria. In fact the former ones have an algal flora composed mostly of eastern mediterranean species, whilst the latter shows strong affinities with the north-african basin, as is demonstrated by the rich well developed belt of Cystoseira sedoides; 3 - several species of atlantic origin, such as Callophyllis laciniata, Peyssonnelia coriacea, P. inamoena and Castagnea chordariaeformis, have been found on the banks (loc. 3, 6, 7).  相似文献   

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Abstract

A method to quantify the dynamic schemes of vegetation based on information functions.—The dynamic schemes of vegetation as proposed by Braun-Blanquet have been never quantified with the aim to give indirect measures of the probability of transition between the types. This work presents a method that quantifies the arrows between the types by means of a redundancy measure. This is calculated by comparing the phytosociological types two by two. Redundancy, as proposed here, measures the similarity between the tables not only based on species composition but also on the basis of species cooccurrence. The method relies on the assumption that in a succession the higher is the redundancy between the types, that are presumably in sequence, the higher is the probability and then the velocity of transition from one type to another one. An example is given with data from coastal dune grasslands of the Venice Lagoon.  相似文献   

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Abstract

The genus Amanita Pers. ex Fr. in Rome neighbourood. — The presence of the genus Amanita in Rome neighbourood, small district, with vegetation and soil diversified, has been studied. The list includes 30 entities (A. caesarea, A. argentea°, A. nivalis, A. vaginata, A. vaginata var. cinerea°, A. fulva, A. crocea°, A. umbrinolutea°, A. lividapallescens°, A. strangulata, A. junquillea, A. eliae°, A. muscaria, A. pantherina, A. alba, A. phalloides, A. phalloides var. alba, A. verna, A. virosa, A. citrina, A. citrina var. alba°, A. porphyria°, A. rubescens, A. spissa. A. excelsa, A. aspera, A. vittadini, A. codinae°, A. strobiliformis, A. boudieri°), 11 new also for latium (°), among these A. codinae and A. vaginata var. cinerea hitherto not found in Italy. At last, the genus in whole region is examined.  相似文献   

15.
Abstract

The vegetation of Lucania: an outline. – The vegetation of Lucania is outlined on the basis of the existing literature and of personal observations. After a short review of the botanical literature a new subdivision of this region is proposed taking into consideration both geological and botanical criteria. The various plant formations are described, among them: the vegetation of the sandy beaches along the Ionian Sea; the Policoro Forest on the coastal plain; the Lygeum spartum stands on the clays; the Quercus cents forests, and the Fagus silvatica ones (comprising the two associations Aquifolio-Fagetum and Asyneumati-Fagetum); the relict Abies alba stands; the summit prairies; the Pinus leucodermis stands.  相似文献   

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Summary

After having summarly described the ecological conditions of the area of the Roman Province which are studied by the author, he lists the plants collected and adds some critical remarks on the taxonomy. He gives a list of a few taxa, which must be regarded as having been found for the first time in Lazio, or are infrequent in this Province.

The author describes the vegetation of some pastures and woods by means of statistical investigations. Finaly he takes into consideration the reciprocal influence exerted by the various plant-communities.  相似文献   

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