Phylogeny,biogeography and ecological diversification of Sarcocornia (Salicornioideae,Amaranthaceae)

Background and Aims Sarcocornia comprises about 28 species of perennial succulent halophytes distributed worldwide, mainly in saline environments of warm-temperate and subtropical regions. The genus is characterized by strongly reduced leaves and flowers, which cause taxonomic difficulties; however, species in the genus show high diversity in growth form, with a mat-forming habit found in coastal salt marshes of all continents. Sarcocornia forms a monophyletic lineage with Salicornia whose species are all annual, yet the relationship between the two genera is poorly understood. This study is aimed at clarifying the phylogenetic relationship between Sarcocornia and Salicornia, interpreting biogeographical and ecological patterns in Sarcocornia, and gaining insights into putative parallel evolution of habit as an adaptation to environmental factors.Methods A comprehensively sampled and dated phylogeny of Sarcocornia is presented based on nuclear ribosomal DNA (external transcribed spacer) and chloroplast DNA (atpB-rbcL, rpl32-trnL) sequences; representative samples of Salicornia were also included in the analyses. To infer biogeographical patterns, an ancestral area reconstruction was conducted.Key Results The Sarcocornia/Salicornia lineage arose during the Mid-Miocene from Eurasian ancestors and diversified into four subclades: the Salicornia clade, the American Sarcocornia clade, the Eurasian Sarcocornia clade and the South African/Australian Sarcocornia clade. Sarcocornia is supported as paraphyletic, with Salicornia nested within Sarcocornia being sister to the American/Eurasian Sarcocornia clade. The American and the South African/Australian Sarcocornia clade as well as the Salicornia clade were reconstructed to be of Eurasian origin. The prostrate, mat-forming habit arose multiple times in Sarcocornia.Conclusions Sarcocornia diversified in salt-laden environments worldwide, repeatedly evolving superficially similar prostrate, mat-forming habits that seem advantageous in stressed environments with prolonged flooding, high tidal movement and frost. Some of these prostrate-habit types might be considered as ecotypes (e.g. S. pacifica or S. pillansii) while others represent good ecospecies (e.g. S. perennis, S. decumbens, S. capensis), hence representing different stages of speciation.     

A quality of life in chronic combat related posttraumatic stress disorder--a study on Croatian War veterans

The main objective of this study was to examine an association of various symptoms in chronic combat-related post traumatic stress disorder (PTSD) and the quality of life in this population. 248 Croatian male war veterans all diagnosed with chronic PTSD were consecutively enrolled in this study as they showed up at the routine check-up. They were given self report questionnaires Trauma Symptom Inventory (TSI-A) evaluating different PTSD symptoms and WHO Quality of Life-BREF assessing four different domains of the quality of life. After independent sample t- test was performed, the presence of each symptom defined by Trauma Symptom Inventory indicated the impairment of all four quality of life domains in a group of subject suffering from it, except of intrusive experience not being associated with the lesser quality in social domain. All quality of life domains were significantly correlated with various PTSD symptoms; however Pearson correlation factors ranged from small to medium value. As expected, PTSD symptoms are associated with lesser quality of life in the affected population. The further research is needed to show possible causal relationship between PTSD and, especially, physical health of these patients.     

AFLPs are incompatible with RAPD and morphological data in Pennisetum purpureum (Napier grass)

Accessions of Pennisetum purpureum in agricultural research centres in sub-Saharan Africa were genotyped using Amplified Fragment Length Polymorphisms (AFLPs) using primer combinations MluI/MseI. Cluster analyses of resulting bands suggested that the samples could be grouped into five large and five small-sized clusters. Principal coordinate analysis revealed two major clusters being well separated, with bulk of the samples forming one, poorly structured cluster. Our analyses failed to reveal the regional groupings found in previous studies using a subset of our sample universe and based on RAPDs as well as morphological and agronomical data. The inability of the AFLP data to clearly demarcate accessions is ascribed to either the presence of high levels of genetic uniformity, or non-optimal primers and/or bad germplasm management practices. The re-registration of all accessions, based on DNA barcoding, is suggested as a means to resolve the lingering problems regarding the identity of accessions.     

Plant communities of trampled habitats in North Korea

Abstract. A syntaxonomic study of trampled plant communities in North Korea is presented. Analytic and synthetic methods of the Braun-Blanquet approach together with a numeric-syntaxonomical analysis (cluster analysis and principal coordinate analysis ordination) were employed. With the exception of the Bryo-Saginetum japonicae, all the associations, such as the Artemisio asiaticae-Plantaginetum asiaticae, Plantagini depressae-Polygonetum avicularis, Polygono avicularis-Potentilletum costatae, Eragrostio multicaulis-Plantaginetum depressae, Euphorbio maculatae-Centipedetum minimae, Digitario pectiniformis-Eleusinetum indicae and Setario viridis-Chlorisetum virgatae, are described for the first time. Some communities also include a number of subassociations. Trampled communities are found along edges of paths and in cracks among paving stones. Soils vary from loamy to sandy and skeletal. A phenomenon of seasonality in expression of ruderal communities was observed in North Korea. It is assumed that this seasonality is controlled by pattern of precipitation showing distinct climatic seasons (e.g. pre-monsoon and post-monsoon periods). The ruderal vegetation seasonality is supposed to become more pronounced towards tropical regions. Several mesophilous or slightly hygrophilous European species occur frequently in North Korean trampled communities including Chenopodium glaucum, C. ficifolium and Potentilla supina. Their occurrence in trampled habitats is hypothesized as being related to high air humidity and associated wet climate.     

Classification of vegetation: Past,present and future

Abstract. This paper is a report on the past, status-quo and perspectives of vegetation classification, still a major occupation of many vegetation scientists. The history of vegetation classification is discussed against a background of several controversial issues such as the problem of continuum vs. discontinuum, naturalness vs. arbitrariness of the nature of plant communities, universality vs. ad hoc character of syntaxonomic schemes, as well as classical versus numerical approaches to data analysis for classification purposes. The development of the methodology of vegetation science and the present image of vegetation classification is documented by a bibliometric analysis of the publication record of four majorjournals: Journal of Vegetation Science, Vegetatio, Phytocoenologia and Tuexenia. This analysis revealed a persisting controversy between traditional and numerical approaches to vegetation classification. A series of important changes in vegetation science (foundation of new journals, change of editorial policy by the established, important meetings) punctuate a period called the ‘Innovation period’. Several trends in the development of methods of vegetation systematics are summarized under the headings formalism, pluralism, functionalism, pragmatism and indeterminism. Some new features, such as the development and improvement of numerical tools, use of large data banks and attempts to summarize the theory of vegetation classification are discussed. The new growth-form system of Barkman initiated a revival of physiognomy-based vegetation classification. Within this framework the use of the character-type concept and the development of new numerical methods for studying the hierarchical structure of character-set types seems to be a promising approach. The achievements of population biology and ecophysiology have affected vegetation science by emphasizing the functionality of species within plant communities. The use of guilds and other functional groups has experienced an increasing interest from vegetation scientists. Applied in vegetation science, fuzzy-set theory has bridged the techniques of classification and ordination of plant communities.     

Common data standards for recording relevés in field survey for vegetation classification

Abstract. In the framework of the European Vegetation Survey common data standards are proposed for recording phytosociological relevés for syntaxonomical classification. The authors wish to establish the notion that common data standards for recording phytosociological data can only be advantageous for advancing the credibility and application of vegetation science, and may stimulate other projects.