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The aim of this study was to evaluate the efficiency of two expert systems in automatic classification of pre-defined yew (Taxus baccata L.) communities in the central and eastern of the Hyrcanian forests. Therefore, initial plant communities were recognized using Two-Way Indicator Species Analysis (TWINSPAN) based on floristic data of 408 releves with 400 m2 areas each. To determine representative species, the integrative results of Phi-coefficient index, constancy ratio, and the ratio of average cover were used. Five plant communities were introduced after transferring the initial communities to the Braun-Blanquet synthesis table. The assignment of releves into the fifth yew associations were done by functional and sociological species groups as two different automatic algorithms of expert system for vegetation classification. The results showed that all releves in the expert system based on functional species groups were correctly assigned to the target groups. This method was in 100% agreement with the existing yew syntaxa. However, 87 releves were not assigned to any of the five pre-defined yew associations, or they were assigned to more than one unit in the Cocktail method, which showed 78.7% agreement with the previously yew syntaxa. Finally, our results illustrate that application of expert system based on functional species groups is preferred to sociological species groups in automatically plant community classification due to the importance of consistency and flexibility of vegetation classifications and the correct assignment of releves to the target units. [ABSTRACT FROM AUTHOR]

Successional processes can be observed for many organisms and resources, but most studies of succession have focused on plants. A general framework has been proposed, advocating that successional patterns in species turnover are predominantly driven by competition, dispersal or abiotic limitation, and that the patterning of species accumulation over time gives clues to which process is most influential in a given system. We applied this framework to succession in communities of wood-living beetles, utilizing ephemeral resources in the form of 60 experimentally created dead aspen high stumps. High stumps were created at sun-exposed sites (high ambient temperature; favourable abiotic conditions) and shaded sites (low ambient temperature; abiotically limiting conditions). The sites were intermixed, ensuring similar dispersal opportunities. Beetle species richness and abundance were monitored with flight interception traps over four consecutive years. Consistent with predictions from the tested framework, several beetle functional groups accumulated species more slowly at the unfavourable shaded sites than at the favourable exposed sites. Species richness at the exposed sites increased rapidly to a plateau, consistent with a limiting effect of competition on community development. Similar results were obtained for beetle abundance and community structure. Part of the variance in beetle community structure was jointly explained by habitat and fungal community composition, suggesting that differences in the composition and developmental rate of fungal communities in the two habitats contributed to the observed patterns. Targeted experimental studies are now required to decisively establish what processes underlie the contrasting successional trajectories in the two environments. [ABSTRACT FROM AUTHOR]

Aims: To create a comprehensive, consistent and unequivocal phytosociological classification of European marsh vegetation of the class Phragmito‐Magnocaricetea. Location: Europe. Methods: We applied the Cocktail method to a European data set of 249,800 vegetation plots. We identified the main purposes and attributes on which to base the classification, defined assignment rules for vegetation plots, and prepared formal definitions for all the associations, alliances and orders of the class Phragmito‐Magnocaricetea using formal logic. Each formula consists of the combination of "functional species groups", cover values of individual species, and in the case of high‐rank syntaxa also of "discriminating species groups" created using the Group Improvement (GRIMP) method. Results: The European Phragmito‐Magnocaricetea vegetation was classified into 92 associations grouped in 11 alliances and six orders. New syntaxa (previously invalidly published according to the International Code of Phytosociological Nomenclature) were introduced: Bolboschoeno maritimi‐Schoenoplection tabernaemontani, Glycerio maximae‐Sietum latifolii, Glycerio notatae‐Veronicetum beccabungae, Schoenoplectetum corymbosi and Thelypterido palustris‐Caricetum elongatae. Based on a critical revision, some other syntaxa were rejected or excluded from the class Phragmito‐Magnocaricetea. Conclusions: This work provides the first consistent classification of the class Phragmito‐Magnocaricetea at the European scale, which is an important tool for nature conservation. Our classification largely respects previously existing concepts of syntaxa, but it also proposes modifications to the recently published EuroVegChecklist. This work also provides a protocol that can be used for extending the current classification to new syntaxa and geographical regions. [ABSTRACT FROM AUTHOR]

ABSTRACT Forest utilization usually has an impact on changes in forest structure and species composition. The species of trees selected and ecosystem management system that refer to biodiversity characteristics will be explained by better knowledge of Functional Species Group (FSG). The purpose of this study was to determine the composition of vegetation recovery based on FSG in production forest managed with silvicultural system known as Selective Cutting and Line Planting System (SCLP) and undisturbed forest known as Germplasm Preservation Areas (GPCA) in Central Kalimantan, Indonesia. The results showed that the proportion of climax group in the entire observation plots was greater than pioneer species group, i.e. climax 100 species and pioneer 59 species. Stand structure both climax and pioneer species group has inverse J shape curve. It means that the species composition of logged-over forest is still in balance condition, characterized with high index of diversity (H' > 3).

Aims Most vegetation classification systems developed for large areas include various inconsistencies. Therefore, we (1) propose a new consistent Cocktail-based approach to redefine the traditional phytosociological classification of species-poor vegetation; (2) apply it to create a classification protocol for aquatic vegetation; (3) implement this protocol in a computer expert system; and (4) test it with a data set previously classified using an older version of the Cocktail method. Methods The new approach uses formal logic to provide formal definitions of vegetation units. In the classification protocol for aquatic vegetation we defined consistent criteria for delimitation of associations according to the concepts that are predominantly used in phytosociology, based on species cover, dominance patterns and functional species groups. We applied these criteria in a computer expert system running in the JUICE 7.0 program, and applied them to a test data set of 12 171 vegetation plots from the Czech Republic containing at least one aquatic species. The new classification was compared with (1) the previous national Cocktail classification based on species cover values and in few cases on sociological species groups, and (2) a non-formalized expert-based classification. Results Thirteen functional species groups were created to build logical formulas of 64 aquatic associations and 5297 (44% of the total data set) vegetation plots were assigned to these associations, i.e. by 4% and 12% more than in the previous Cocktail and expert-based classifications, respectively. There was 94% and 83% classification agreement with the previous Cocktail and expert-based classification. Conclusions The new approach produces a formal, consistent and unequivocal classification of species-poor vegetation with several advantages over similar approaches. It provides not only a set of formal definitions of vegetation units, but also a set of rules for building such definitions. All associations with common characteristics are defined by structurally identical formulas, ensuring consistency of the classification. While similar approaches for species-rich vegetation use sociological species groups, which are not applicable to species-poor vegetation, the new approach introduces the use of functional species groups, which reflect vegetation physiognomy and spatial structure and, in combination with species dominance, enable the classification of species-poor vegetation in a similar manner as in traditional phytosociology. [ABSTRACT FROM AUTHOR]