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Fishponds of Hawai‘i
A field guide to the damselflies and dragonflies
A Field Guide to the Orchids of Great Britain and Ireland
A History of the Molecular Revolution
The Psychology of Boredom
A Natural History

Abstract

Mantle vegetation includes plant communities dominated mostly by shrubs and occurs in habitats where the typical tree layers meet difficulties to evolve. This study was conducted in three areas of Bulgaria – Western Balkan Range, Western Sredna Gora Mt. and the Fore-Balkan. Numerical classification and ordination were performed by PC-ORD and JUICE software packages. Diagnostic species were determined by calculating the Phi-coefficient. Two associations and one plant community of the Berberidion alliance were recognized – Corno-Ligustretum Horvat ex Trinajstić ---amp--- Z. Pavletić 1991, Pruno spinosae-Ligustretum vulgaris Tüxen 1952 and Elytrigia repens-Crataegus monogyna community. The latter considered as a successional stage of shrub encroachment into the grasslands. Its species composition is very close to that of the ass. Corno-Ligustretum. The species composition of ass. Pruno-Ligustretum represents a mixture of species characteristic for dry and mesic grasslands, fringe and forest vegetation. The Crataego-Prunetea class is still poorly studied in Bulgaria and much more data from all regions in the country have to be collected.

Abstract

Echinophora spinosa L., a perennial member of the Apiaceae (Umbelliferae) family is known to be native to southern Europe and Algeria. More recently this taxon was collected from Tabarka (Jendouba-Kroumiria, North-Western of Tunisia) and is reported as a new species for the terrestrial flora of Tunisia. It is described and illustrated and notes on its ecology and phytosociological remarks are provided.

Abstract

Based on hierarchical classification of more than 300 phytosociological relevés of basophilic black and (or) Scots pine communities in the Southern, Eastern and Southeastern Alps we described a new association Rhodothamno chamaecisti-Pinetum sylvestris, into which we classify stands that have until now been discussed in the framework of subassociations Fraxino orni-Pinetum nigrae pinetosum sylvestris, laricetosum deciduae and (partly) caricetosum humilis, and are floristically slightly similar also to certain forms of the association Erico-Pinetum sylvestris. The stands of the new association are for now classified into Natura 2000 habitat type Southeastern-European Pinus sylvestris forests (91R0), within it we propose a special habitat subtype Southeastern-Alpine Scots pine forests, and into a new forest site type Southeastern-Alpine Scots pine forest. At the contact of the Julian and Dinaric Alps we described a new subassociation Genisto januensis-Pinetum sylvestris campanuletosum cespitosae, which comprises also a Natura 2000 species Primula carniolica.

Abstract

The study presents a floristic-sociological classification of the forest vegetation of Kyiv urban area. We identified 18 syntaxa within 7 classes, 7 orders, 8 alliances, and 3 new associations were allocated (Aristolochio clematitis-Populetum nigrae, Galio aparines-Aceretum negundi, Dryopterido carthusianae-Pinetum sylvestris). We analyzed vegetation data using quantitative approaches of ordination and phytoindication. Considering many relevés of transitional nature in the collected data on urban forests, the clustering algorithm of DRSA (Distance-Ranked Sorting Algorithm) was applied to classify vegetation matrix. Large-scale comparative floristic analysis of syntaxa from different regions and countries have been conducted and summarized in differentiating tables.