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Abstract

Biological invasion is a crucial problem in the world because of its negative consequences for protected areas. The degradation stage of vegetation might affect the success of invasion. One of the most abundant and threatening invasive species is the common milkweed (Asclepias syriaca L.) which has invaded already 23 countries of Europe and in several habitat types its further spreading is promoted by climate change. Pannonian sand grassland is one of the most threatened habitat by common milkweed invasion. Therefore, invasion in sand grassland vegetation is an important issue. However, the effects of the invasive plant in the open sand grassland are rather controversial. In order to clarify the existing contradictory results, the study was carried out in a strictly protected area, near Fülöpháza (Hungary) in a reserve core area in a UNESCO biosphere reserve. Microcoenological study was applied to determinate the fine-scale community characteristics of non-invaded and invaded stands in natural and seminatural vegetation and data were processed by Juhász-Nagy's information theory models. Shannon diversity of species combinations (compositional diversity) which describes the ways of the coexistence of species, and the number of realized species combinations were used for measuring beta diversity. Differences between stands were analyzed by two-way ANOVA. The maximum compositional diversity of species and main life-forms (annuals, perennials and cryptogams) did not differ significantly between the non-invaded and invaded stands. In contrast, significantly larger characteristic areas of compositional diversity were detected in the invaded stands. Based on these results, it could be concluded that diversity of species combinations did not change but those values have shifted to coarser scales in case of invaded stands. The direction of this change suggests a kind of impoverishment in the presence of Asclepias. Thus, it is worth mentioning from the invasion management point of view that protection of the habitats against disturbance is a more cost-effective and successful way than protection against the establishment or extirpation of invasive species, since disturbance facilitates the invasions throughout the impoverishment of the community.

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Orvosi Hetilap
Authors: Zoltán Mátrai, Gusztáv Gulyás, Csaba Kunos, Ákos Sávolt, Emil Farkas, András Szollár, and Miklós Kásler

19 219 225 Medina-Franco, H., Soto-Germes, S., Ulloa-Gómez, J. L., et al.: Radiofrequency ablation of invasive breast carcinomas: a

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38 325 330 Bragg, T.B. and L.C. Hulbert. 1976. Woody plant invasion of unburned Kansas bluestem prairie. J. Range Manage. 29

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Daehler, C.C. 2003. Performance comparisons of co-occurring native and alien invasive plants: implications for conservation and restoration. Ann. Review Ecol. Syst. 34: 183–211. Daehler C

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Orvosi Hetilap
Authors: Anna Egresi, Gabriella Lengyel, and Krisztina Hagymási

J. Gastroenterol., 2010, 16 (10), 1171–1176. Usluer, G., Erben, N., Aykin, N., et al.: Comparison of non-invasive fibrosis markers and classical liver biopsy in chronic hepatitis C. Eur. J. Clin. Microbiol

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Balogh, L. (2001): Invasive alien plants threatening the natural vegetation of Őrség Landscape Protection Area (Hungary) . — In: Brundu, G., Brock, J., Camarda, I., Child, L. and Wade, M. (eds): Plant

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Physiology International
Authors: DN Nandakumar, P Ramaswamy, C Prasad, D Srinivas, and K Goswami

Introduction Glioblastoma (GBM) is the most common malignant primary brain tumor with an extremely invasive phenotype. Regardless of advances in current treatment regimens, prognosis remains poor with an overall survival rate

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CR : Invasive Enterobacter sakazakii disease in infants . Emerg Infect Dis 12 , 1185 – 1189 ( 2006 ) 29. Cahill SM , Wachsmuth IK

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Orvosi Hetilap
Authors: Zoltán Galajda, Géza Jakó, Ronald von Jakó, and Árpád Péterffy

Massetti, M., Buklas, D., Bichi, S. és mtsa: Minimally invasive thoracic retractors. Ann. Thorac. Surg., 2006, 81 , 2336–2337. Bichi S. Minimally invasive thoracic retractors

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CR475 Shibl, A.M., Memish, Z.A., Al-Kattan, K.M.: Antibiotic resistance and serotype distribution of invasive pneumococcal diseases before and after introduction of pneumococcal conjugate

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