Popiela et al. (2015) Acta Botanica Gallica

Popiela A., Łysko A., Molnár V.A., Kącki Z., Lukács B. A.(2015): Elatine triandra Schkuhr (Elatinaceae) in Europe, with special emphasis on the central part of thecontinent. – Acta Botanica Gallica – Botany Letters 162 DOI:10.1080/12538078

Abstract

Elatine trianda Schkuhr is the most widespread species within the genus Elatine L.; it can be found in all continents, except Antarctica, but the majority of the locations have been recorded in Europe. The study is based on an extensive dataset of literature, herbaria and web data, which spans the period 1828–2012. The range of the species in Europe is disjunctive; it covers the southern and western parts of the Central European Plain and the northern shores of the Baltic Sea, it can also be found along some river valleys. In Central Europe many localities especially isolated ones in northern part of the range are historical now. According to the dataset we determined that E. triandra can be observed between May and October. We also found a remarkable historical decrease of observation time. We found that species observation has a near significant shift since 1828 that correlates to changes in environmental variables. Depending on the environmental conditions individuals of the taxon could develop in two forms: terrestrial and aquatic. The aquatic form is characterized by twice longer stems and internodes, and also almost twice longer lamina and petiola. E. triandra seeds show consistent characteristics both in terms of forms and populations. Our studies show that the best diagnostic feature, in addition to the construction of flowers, are size, shape and surface structure of seeds. In Central Europe E. triandra occurs exlusively in communities classified to the Isoëto-Nano-Juncetea, however the number of species characteristic for the class and lower syntax in patches decreases from north to south of the continent.

Keywords

chorology, ephemerophyte, Isoëto-Nano-Juncetea, phytogeography, vegetation, morphology, maps, phenology

Lovas-Kiss et al. (2015) Acta Societatis Botanicorum Poloniae

Lovas-Kiss Á., Sonkoly J., Vincze O., Green A.J., Takács A. & Molnár V. A. (2015): Strong potentialfor endozoochory by waterfowl in arare, ephemeral wetland plant species (Astragalus contortuplicatus, Fabaceae). – Acta Societatis Botanicorum Poloniae 84(3): 321–326.

Abstract

It was proposed previously that passive dispersal by migratory aquatic birds explain the widespread distribution of many wetland organisms. Several experimental studies have shown that many widespread wetland plant species can be readily dispersed within the guts of Anatidae. However, it is unclear whether plants with a more restricted distribution are able to disperse via waterbirds. This paper addresses the dispersal ability and germination ecology of the little-known Hungarian milkvetch Astragalus contortuplicatus, which occurs on banks of continental rivers and has a limited and unpredictable distribution. To test whether limited capacity for endozoochory by waterfowl could explain the sporadic appearance of this species, we force-fed ten captive mallards (Anas platyrhynchos) with 100 milkvetch seeds each. Droppings were collected for up to 45 h after feeding. Intact and viable seeds were found in the droppings of each mallard, and altogether 24.7% of seeds fed were recovered intact. The proportion of retrieved seeds that germinated (27.0%) was significantly higher than that of untreated control seeds (0.5%), but significantly lower than that of mechanically scarified seeds (96.0%). Retrieved seeds that germinated developed into healthy mature plants. Given the average flight velocity of mallards, seeds of A. contortuplicatus may travel up to 1600 km inside the digestive tract of migrating individuals. Our results suggest that avian vectors may be more important for the dispersal of rare higher plants (especially those with a hard seed-coat) than hitherto considered. Moreover, they suggest that rarity does not necessarily indicate limited dispersal ability, and may instead be explained by specific habitat requirements.

Keywords

Anas platyrhynchos, germination experiment, mallard, ornitochory, seed dispersal, seed ecology, seed viability

Molnár V. et al. (2015) Preslia

Molnár V.A., Sonkoly J., Lovas-Kiss A., Fekete R., Takács A., Somlyay L. & Török P. (2015): Seed of the threatened annual legume, Astragalus contortuplicatus, can survive over 130 years of dry storage. – Preslia 87(3): 319–328.

Abstract

Long-term seed viability is of crucial importance for short-lived species, since persistent seed banks can buffer the fluctuations in the establishment of plants from year to year. Temporarily flooded habitats are an unpredictable environment for plants, and for some species the only chance they have of surviving is the formation of persistent seed banks. Astragalus contortuplicatus is an annual species of periodically flooded habitats and is considered an endangered species in Hungary. Altogether 1993 seeds of this species were tested in a germination experiment: 1200 were freshly harvested and 793 were collected from herbarium specimens of various ages. Seed viability was tested using the germination method. The freshly harvested seeds were used for selecting the best out of seven frequently used dormancy-breaking methods for this species. The highest percentage of germination was recorded for the combined treatment of scarification and light. Thus, this method was used to test the viability of the seeds collected from herbarium specimens. The oldest seeds that germinated were 131 years old. Until now there are no records of seeds of herbaceous legumes germinating that are more than 100 years old. This record is the 9th oldest of all the literature records of viable seeds originating from biological collections. All the seeds that germinated developed into healthy, fertile plants, the seeds of which also readily germinated. Fitted linear regression showed a significant negative relationship between seed age and percentage germination. Based on this linear regression the calculated theoretical maximum viability is 309 years. Our results suggest that seeds of A. contortuplicatus stored in collections can be successfully used in this species’ reintroduction for conservation purpose, to areas in which the plants were collected.

Keywords

biological collections, Fabaceae, hard seeds, herbarium, Hungary, physical dormancy, scarification, persistence, seed longevity, seed storage

Deák et al. (2015) Ecological Complexity

Deák, B., Valkó, O., Török, P., Kelemen, A., Tóth, K., Miglécz, T., Tóthmérész, B. (2015): Reed cut, habitat diversity and productivity in wetlands. Ecological Complexity 22: 121-125.

Highlights

• We tested the effects of winter cutting versus abandonment on wetland diversity.
• Winter cutting decreased habitat diversity and structural heterogeneity.
• Unmanaged wetlands harboured high amount of biomass in heterogeneous distribution.
• Diversity of vegetation types correlated positively with all biomass fractions.
• Intensive reed cut decreases wetland diversity by overriding edaphic conditions.

Abstract
There is a conflict between nature conservation and thatching industry regarding the management of reedbeds. On one hand, reedbeds are of an economical importance by providing thatching material, on the other hand, they harbour several endangered species. Reedbeds are typically managed by winter cutting, but its impacts on biodiversity are poorly understood. Our aim was to study the effects of winter cutting on the habitat diversity and structural heterogeneity of wetlands in a lowland alkali landscape (East-Hungary). We tested the following hypotheses: (i) Both diversity of plant species and habitat diversity are lower in winter cut wetlands compared to unmanaged stands. (ii) The distribution of biomass (green biomass, litter and standing dead biomass) is more homogeneous in winter cut wetlands compared to unmanaged ones. We found that winter cutting decreased habitat diversity and structural heterogeneity at multiple scales. Number of plant species and all measures of habitat diversity (number of patches, vegetation types and the length of vegetation margins) had lower scores in cut wetlands than in unmanaged ones. We found that unmanaged wetlands harboured high amount of accumulated biomass and they also maintained high habitat diversity likely due to the heterogeneous distribution of the biomass. In unmanaged wetlands, biomass accumulation did not decrease habitat diversity and also contributed to a higher structural heterogeneity. In cut wetlands, expansion of reed was an important driver of the decrease in habitat diversity and structural heterogeneity. Reed expansion likely overrode fine-scale edaphic conditions (hydrology and salinity) in shaping vegetation patterns; thus we suggest to avoid intensive winter cutting.

Keywords
Biomass, Landscape, Management, Margin, Marsh, Phragmites

Löki et al. (2015) Willdenowia

Löki V., Tökölyi J., Süveges K., Lovas-Kiss Á., Hürkan K., Sramkó G. & Molnár V. A. (2015): The orchid flora of Turkish graveyards: a comprehensive survey. Willdenowia 45(2): 231–243.

Abstract
Graveyards are widely known among orchidologists as finding places of several orchid species in Turkey, including some very rare and localised ones. Graveyards provide places that are less strongly affected by landscape-altering human activities than other habitats because of their special cultural roles and religious privileges. In this study we performed a comprehensive survey of Turkish graveyards as orchid habitats. In total, 300 graveyards were studied in 30 provinces of Turkey in 2014. 84 orchid taxa (almost half of the known Turkish orchid flora) were found in 208 graveyards. From the studied provinces two south-southwestern provinces (Muğla, Antalya) emerged as peaks of species richness. This finding is in accordance with the overall biogeographical pattern of orchid diversity in Turkey. Our survey also contributes new floristic data to the orchid flora of Turkey. We documented salep collection in 10 graveyards from six provinces involving nine species. Altogether, we found orchids in 69% of the inspected graveyards, allowing us to conclude that the occurrence of orchids in Turkish graveyards is not a rare phenomenon. Thus, graveyards can be important refuges for orchids in the changing economical and agricultural circumstances of Turkey.

Keywords
Asia minor, cemetery, flora of Turkey, Near East, Orchidaceae, salep, SW Asia

E. Vojtkó et al. (2015) Acta Biologica Hungarica

E. Vojtkó A., Sonkoly J., Lukács B. A. & Molnár V. A. (2015): Factors affecting reproductive success in three entomophilous orchid species in Hungary. Acta Biologica Hungarica 66(2): 231–241.

Abstract
The reproductive success of orchids is traditionally estimated by determining the fruit-set of individuals. Here, we investigated both the fruit and the seed production of three orchid species and the factors that may affect individual fruit-set, like pollination strategy, individual traits or the annual amount of precipitation. The species (Dactylorhiza sambucina (L.) Soó, Dactylorhiza majalis (Rchb.) P. F. Hunt & Summerhayes and Platanthera bifolia (L.) L. C. M. Richard) were studied in three consecutive years (2010–2012) in the Bükk Mountains, Hungary. All the three species were proved to be non-autogamous by a bagging experiment. Data analyses showed significant differences between seed numbers but not between fruit-sets of species. There was no statistical difference in individual reproductive success between wet and dry years however, the effect of the annual amount of precipitation is significant on the population level. Comparison of published fruit-set data revealed accordance with our results in P. bifolia, but not in D. sambucina and D. majalis. We assume that the surprisingly high fruit-set values of the two Dactylorhiza species may be due to the fact that the pollination crisis reported from Western European countries may not be an actual problem in the Bükk Mountains, Hungary.

Keywords
Dactylorhiza majalis, Dactylorhiza sambucina, fruit-set, Platanthera bifolia, pollination crisis

Molnár V. et al. (2015) Applied Ecology and Environmental Research

Molnár V. A., Löki V., Takács A., Schmidt J., Tökölyi J., Bódis J. & Sramkó G. (2015): No evidence for historical declines in pollination success in Hungarian orchids. Applied Ecology and Environmental Research 13(4): 1097–1183.

Abstract
Pollination crisis (the decline of pollinator populations) is a global phenomenon which threatens biodiversity, human welfare and economy. The degree to which different plant populations/species are affected by pollination crisis is still unclear. In this study, long-term herbarium dataset was used to quantify the reproduction rate of Hungarian orchids between 1853 and 2008. We quantified fruit-set rate of 663 specimens belonging to 27 species. Data were available from an average of 10.3±9.3 localities, 76.5±43.2 years, and 23.4±25.6 specimens per species. Herbarium data were validated with field-observed data in case of the different pollination strategies. According to our results, the reproductive success of the vast majority of orchid species has not changed during time and pollination crisis is not apparent in Hungary at least until the end of the 20th century.

Keywords
herbaria, natural history collections, Orchidaceae, pollination crisis, pollination mode

Boda et al. (2015) Journal of Insect Conservation

Réka Boda, Csaba Bereczki, Adrienne Ortmann-Ajkai, Péter Mauchart, Bálint Pernecker, Zoltán Csabai (2015): Emergence behaviour of the red listed Balkan Goldenring (Cordulegaster heros Theischinger, 1979) in Hungarian upstreams: vegetation structure affects the last steps of the larvae. Journal of Insect Conservation 19(3): 547-557.

Abstract
In odonates, the emergence behaviour and finding suitable substrates for successful molting may influence the next generation and ultimately can determine the survival of the entire population. Understanding emergence behavior of endangered species and those granted special conservation status is particularly important. Despite this, little is known about the life history and emergence behaviour of Cordulegaster heros, a characteristic inhabitant of headwater streams. We hypothesised that the taxonomic composition and structure of the vegetation significantly affect the travel distance to the emergence site and the substrate choice. Two stream sections with different riparian zone vegetation were surveyed for exuviae in the emergence periods in two consecutive years, supported with detailed vegetation mapping. Significant differences were found between the vegetation characteristics at the two sites and differences were also found between emergences in edge zones within a site, indicating that the importance of vegetation structure operates within the scale of sites as well as between sites. At the site with more diverse vegetation, smaller horizontal but higher vertical travel distances and more varied emergence substrate choice were found. Habitat composition and complexity appears to determine the emergence behaviour of C. heros, so for the successful conservation of this species we recommend choosing appropriate forest management regimes and even maintaining riparian forests in near-pristine condition.

Keywords
Odonata, Exuviae, Travel distances, Emergence-site selection and preference, Vegetation grid mapping

Boda et al. (2015) Hydrobiologia

Réka Boda, Csaba Bereczki, Bálint Pernecker, Péter Mauchart, Zoltán Csabai (2015): Life history and multiscale habitat preferences of the red-listed Balkan Goldenring, Cordulegaster heros Theischinger, 1979 (Insecta, Odonata), in South-Hungarian headwaters: does the species have mesohabitat-mediated microdistribution? Hydrobiologia, DOI: 10.1007/s10750-015-2317-y

Abstract
Life cycle and microdistribution patterns of Cordulegaster heros, a charismatic species for nature conservation, are poorly known. Life history characteristics and multiscale habitat preferences of the larvae were followed for one year in monthly intervals by systematic samplings in eight headwaters, which resulted in data on 2562 individuals. We hypothesized that meso- and microhabitat complexity play an important role in forming the population structure and microdistribution of the species. Based on the distribution of the consecutive larval instars, duration of later stages and time of molt and emergence, the larval development of C. heros in the Mecsek Mountains lasts for at least three, but with a maximum of four years. All three levels of the multi-habitat structure [habitat (sites), and meso- (riffle/pool sequence) and microhabitats (biotic and different particle-sized abiotic types)] have significant effects on the spatial distribution of the larvae. Densities and population structures vary among the sites, but mesohabitat type and microhabitat diversity (heterogeneity within a pool or riffle) govern the microdistribution. C. heros prefers pools with small or medium microhabitat heterogeneity and higher proportion of small particle-sized substrates, especially in younger stages. Older larvae are less sensitive for these effects.

Keywords
Odonata, Larvae, Life cycle, Spatial microdistribution, Meso- and microhabitat preference

Deák et al. (2015) Basic and Applied Ecology

Balázs Deák, Orsolya Valkó, Péter Török, András Kelemen, Tamás Miglécz, Szilárd Szabó, Gergely Szabó, Béla Tóthmérész (2015): Micro-topographic heterogeneity increases plant diversity in old stages of restored grasslands. Basic and Applied Ecology, in press. doi:10.1016/j.baae.2015.02.008

Abstract

It is a truism in ecology that environmental heterogeneity increases diversity. Supporting field studies are mostly concerned with a large-scale topographic heterogeneity, ranging from a couple of meters to landscape-scale gradients. To test the role of fine-scale micro-topography on plant diversity, we studied the initial vegetation of recently filled (1-year-old), and established vegetation on old (7-year-old) soil-filled channels in an alkali landscape, East-Hungary. We hypothesised that (i) recently filled channels are characterised by a high cover of ruderal species and high species diversity and (ii) high micro-topographic heterogeneity increases the diversity of species and plant strategy types (mixed C-S-R categories) in early stages but later on this effect diminishes. We found that diversity of species and plant strategy types was higher in recently filled channels compared to old filled channels. Micro-topographic heterogeneity had no effect on the studied vegetation parameters in recently filled channels. Conversely, in old filled channels higher micro-topographic heterogeneity resulted in higher diversity and lower cover of the dominant grass Festuca pseudovina. Higher micro-topographic heterogeneity resulted in increased ruderality and decreased stress-tolerance, but it did not increase the diversity of plant strategy types. In contrast with former studies, we found that a couple of centimeters of micro-topographic heterogeneity had no effect on vegetation in recently filled channels, but supported a high diversity in old filled channels. An important practical implication of our study is that in grassland restoration projects, micro-topographic heterogeneity has a crucial role in sustaining biodiversity.

Keywords

Alkali landscape, C-S-R strategies, Elevation, Functional diversity, Grassland restoration, Plant trait, Soil disturbance, Succession, Topography

Deák et al. (2014) Flora

Deák, B.; Valkó, O.; Alexander, C.; Mücke, W.; Kania, A.; Tamás, J.; Heilmeier, H. (2014): Fine-scale vertical position as an indicator of vegetation in alkali grasslands - case study based on remotely sensed data. FLORA 209: 693-697.

 

Highlights

• Small-scale elevation gradients affect salt and water balance in alkali landscapes.•
• Elevation–vegetation correlations have not been studied in inland alkali landscapes.•
• We linked elevation data with vegetation patterns using remote sensing techniques.•
• Main vegetation categories can be separated by their small-scale vertical positions.•
• Remote sensing based vegetation mapping is an ideal tool in such complex landscapes.

Abstract
Vertical position is an important driver of vegetation zonation at multiple scales, via determining abiotic environmental parameters, such as climate, soil properties and water balance. In inland alkali landscapes, elevation is a key factor for understanding patterns of salt accumulation and water table which is therefore considered a good indicator of alkali vegetation types. Remote sensing techniques offer viable solutions for linking elevation data to vegetation patterns by providing an elevation model of extended areas. Our goal was to test the relationships between fine-scale differences in vertical position and vegetation patterns in inland alkali landscapes by vegetation data collected in the field and elevation data generated using airborne laser scanning (ALS). We studied whether vertical position influences vegetation patterns at the level of main vegetation groups (based on alliances) or even at the level of associations. Our study sites were situated in a lowland alkali landscape in Hortobágy National Park (East-Hungary). We grouped the associations into four main vegetation groups: loess grasslands, alkali steppes, open alkali swards and alkali meadows. Even though we detected a very limited range (121 cm) in the vertical position of the main vegetation groups, they were well separated by their vertical positions. At the level of associations, a more detailed elevation-based distinction was also possible in many cases. The revealed elevation–vegetation correlations show that high-resolution mapping based on ALS remote sensing techniques is an ideal solution in complex lowland areas, such as alkali landscapes. Our findings suggest that in other types of lowland landscapes, characterised by elevation differences, the applied method might hold a great potential as a supporting tool for vegetation mapping.


Keywords
Vegetation zonation, Airborne laser scanning, Saline grassland, Festucion pseudovinae, Natura 2000, Digital terrain model