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• The role of soil seed bank in restoration and dynamics of Hungarian plant communities

  116-135

  Réka Kiss

  Views:

  133

  Soil seed bank has an important role in maintaining plant populations and communities, in regeneration processes, and also provides information about the history of the studied site, the past land use practices, the biotic and abiotic changes and about the current degradation degree. In Hungary there are many researchers related to the seed bank, but from the last few years we do not have a comprehensive work about the results of these works. My goal is to report on the results of former seed bank researches in Hungary and also to highlight the missing topics and further research opportunities. The review is based on 49 articles, the oldest one dates back to 1922, the newest one was published in 2015. Most of the studies use greenhouse or laboratory germination tests to determine the viability of seeds. The earliest studies, which examined the weed seed bank of farmland soils found, that the seed bank was much higher than the total seed bank found on natural and semi-natural habitats studied later. Researchers found the lowest seed bank density in forests. Disturbed sites and former agricultural sites had higher seed bank densities than sites without agricultural use. Most part of seed bank was located in the upper soil layer in all studied communities. In most studies usually a small similarity was detected between the composition of soil seed bank and aboveground vegetation, which suggests that the seed bank has a subordinate role in regeneration processes. Seed bank type classification is lacking from the three-quarter of Hungarian flora species, despite that it is essential for protecting species and communities and for developing proper protection against invasive and alien species.

• Specific variability and ecological meaning of seed weights

  295-330

  Judit Sonkoly

  Attila Molnár V.

  Péter Török

  Views:

  189

  There is an almost twelve order of magnitude difference in the seed weight of recent plant species. Studying the causes, patterns and consequences of this high variability is a crucial issue in plant ecology. In this paper we summarise the main conclusions of the studies in this topic to get a broad and general view of the possible explanations of high variability in seed weights and its consequences on dispersal, seed predation, seed bank formation, germination, establishment and plant growth, and on the structure and function of plant communities. Because of the extremely high number of papers published in this topic, we aimed at to concentrate on papers published in highranked international journals in the last few decades, having a special focus on publications from the Carpathian Basin. It was found that growth form, body size, genom size, latitude and light availability are responsible for the detected high variability in the seed weights of species. Infra-individual variability is mostly caused by the effects of the position on the maternal plant and the seed size – seed number trade-off. The effect of dispersal by wind or by seed predators on the variability of seed weights and its ecological consequences are the most studied. Predicting persistence on the basis of seed size and seed shape also has been a popular research topic lately. Studying the effects of seed weight variability on the structure of plant communities is also becoming more and more important, but no general conclusions could be drawn yet.

• Discovery of a new large population of Prunus tenella on a young old-field suggests remarkable regeneration ability of the species

  32-38

  Balázs Deák

  Tibor Orcsik

  Ádám Bede

  Orsolya Valkó

  Views:

  329

  Kurgans are ancient burial mounds built by nomadic steppic cultures across Eurasia.
  These monuments are important cultural landmarks, and often also preserve the remnants of dry grasslands even in intensively used agricultural landscapes. In the past centuries, many kurgans have been ploughed and their vegetation has been destroyed. Due to their recent inclusion in the agrienvironmental schemes in Hungary, crop production has been ceased on many kurgans in the past years. Here we present an interesting botanical discovery which we made during our country-scale survey of spontaneously recovering grasslands on kurgans. We discovered a large population of approximately 15,000 shoots of the protected loess grassland plant Prunus tenella Batsch (syn.: Amygdalus nana L.) on the Fekete-halom kurgan near Tiszainoka, in the centre of the Great Hungarian Plain. The mound had been used as an intensive cropland until 2014. Most probably, the plants could re-establish from some hidden shoots that could persist in the refuge provided by the concrete elements of a geodesic mark, and after the cessation of ploughing it could expand onto the north and west-facing slopes of the mound by sprouting and by germination from the persistent soil seed bank. Besides the conservation importance of this floristic discovery, it also suggests that spontaneous regeneration can be an effective restoration measure and that kurgans abandoned from agricultural cultivation can serve as suitable habitats for rare and endangered species.