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Abstracts of volume 72, no. 1, 2000

Chytrý M. (2000): Formalized approaches to phytosociological vegetation classification. - Preslia, Praha, 72: 1-29. [In Czech]
The current theory and methods of phytosociological vegetation classification are divided into two major types: imperfectly formalized approaches, which build classifications without explicit description of the classification process, and formalized approaches, which aim at precise definitions of classification criteria and algorithms, thus yielding repeatable classifications. These two approaches are not antagonistic, as each of them is better applicable in different situations. As a rule, the imperfectly formalized approach is invaluable in fine-scale classifications at the landscape level, whereas the formalized approach is superior for large-scale vegetation surveys. In this paper, application of the formalized methods of vegetation classification in phytosociology is reviewed. First, classification criteria used in vegetation classification are evaluated. Second, possibilities for formalizing the phytosociological field sampling procedure are discussed, including the sample plot choice, spatial arrangement and size. Third, formalized approaches to data analysis are reviewed, including concepts of character species, sociological species groups, fidelity, hierarchy of classification units, deductive classification method, numerical classification, and nomenclature rules. Finally, recent developments of formalized classification are summarized with respect to large-scale vegetation surveys, phytosociological databases, analysis of large datasets and expert systems.

Dubyna D. V. & Neuhäuslová Z. (2000): Salt meadows (Festuco-Puccinellietea) of the Biryuchij Island Spit in the Azov Sea, Ukraine. - Preslia, Praha, 72: 31-48.
Phytosociological and ecological characteristics of salt meadows (class Festuco-Puccinellietea) of the Biryuchij Island Spit (Azov Sea, Ukraine) are given. The following associations have been studied in detail: (1) Plantagini salsae-Juncetum gerardii, on temporarily waterlogged solanchak-like soils in narrow depressions with relatively low calcium content, (2) Scorzonero parviflorae-Taraxacetum bessarabici influenced by grazing and trampling, in shallow depressions, with relatively low salt content. (3) Artemisio santonicae-Elytrigietum elongatae in mown sites, covering moderate elevations behind the coastal ridge, with calcium-rich, temporarily drying out soils. (4) Tripolio vulgaris-Aeluropetum littoralis occurs on moister soils of lower positions, moderately to highly saline. Two subassociations were recorded (5) Puccinellietum giganteae occurs on soils with different degrees of salinization and different texture, with an ecological optimum in temporarily flooded sites of degraded solonchaks. Plantagini salsae-Juncetum gerardii, Artemisio santonicae- Elytrigietum elongatae and Tripolio vulgaris-Aeluropetum littoralis are described as new associations in the present paper.

Balátová-Tuláčková E. (2000): Contribution to the knowledge of Molinietalia communities in the Moravskoslezské Beskydy Mts (NE Moravia). - Preslia, Praha, 72: 49-72. [In German]
The West Carpathian Moravskoslezské Beskydy Mts, mostly built from Godul Flysh, are poor in communities of the order Molinietalia. They occur on slopes or in river valleys permanently influenced by underground water or springs. Eight associations of the alliance Calthion were found, i. e. Chaerophyllo hirsuti-Calthetum, Chaerophyllo hirsuti-Crepidetum paludosae, Scirpetum sylvatici (occurring frequently), Angelico- Cirsietum palustris, Cirsietum rivularis (the most widespread community), Filipendulo-Menthetum longifoliae, Lysimachio vulgaris- Filipenduletum (both rarely occur in marginal parts of the studied territory) and Chaerophyllo hirsuti-Filipenduletum. Particular associations are characterized by properties of the topmost part of the soil profile and by their species richnes. Cirsietum rivularis and Scirpetum sylvatici were divided in the highest number of subassociations. Importance of the moist to moist-wet communities of the Molinietalia order for mountain regions is discussed.

Fiala K. (2000): Proportion of living biomass in the total dry mass of belowground organs of various plant communities. - Preslia, Praha, 72: 73-85.
Proportion of living belowground plant biomass estimated for various types of meadows, grass stands of clear-cut areas, sedge stands of wetlands and for Cuban savannas and forests is reviewed. Analysis was done using a staining technique and laborious visual separation of living belowground biomass from soil cores and blocks. The differences in the amount of living belowground plant biomass are mostly associated with the type of plant community. The highest amounts of living belowground biomass (1100 to 2300 g.m -2) were recorded most frequently in the unmown moist meadow stands (percentage of living belowground biomass was over 60%) and in mountain grass stands of clear-cut sites (66-95%). A lower percentage and amount of living biomass was found in the driest habitat (23%, 860 g.m-2) and in several wetlands (10-13%, about 500 g.m-2 or less). Mown meadows were characterized by a lower percentage of living belowground biomass and lower dry mass of total and living belowground plant parts. Living belowground biomass of 433 and 517 g.m-2 (34 and 50%) was recorded in natural savannas, while 745 (74%), and 512 to 1122 g.m- 2 (39-65%) was recorded, respectively, in the anthropogenic savanna stands dominated by Axonopus compressus and Paspalum notatum. The percentage of living fine roots in the total dry mass of fine roots of Cuban forests varies considerably: 41 and 47% (554-758 g.m- 2) in mangrove forests, 30 and 56% (64-90 g.m- 2) in evergreen broad-leaved mountain forests and 23 and 49% (87- 200 g.m-2) in semideciduous lowland forests. Both the proportion of living plant organs in total belowground dry mass and the amount of belowground plant necromass vary greatly, which may reflect differences in root mortality and the decomposition rate of dead belowground plant parts associated with various habitat conditions.

Kirschner J. & Zázvorka J. (2000): New names of taxa included in the 6th volume of “Flora of the Czech Republic”. - Preslia, Praha, 72: 87-89.

Three new combinations are given to validate new names used in the 6th volume of Flora of the Czech Republic (“Květena České republiky”), i. e. Orobanche alba subsp. major, Phelipanche purpurea subsp. bohemica (Orobanchaceae) and Centaurium litorale subsp. compressum (Gentianaceae).


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