Long-term monitoring of populations contributes to the better understanding of population dynamics of species. A population of the orchid Himantoglossum adriaticum H. Baumann was monitored in Keszthely Hills in western Hungary during the period 1992-2008. To assess reproductive output in each year, the number of flowering individuals, as well as the number of flowers and fruits produced per plant were recorded. The reproductive traits studied (except the number of flowering plants and seedpods) did not varied considerably, they showed low temporal variability over years, while the other two characteristics mentioned had high temporal variability. Mean number of flowers produced per plant over all years was 31. Fruitproduction was often low or zero. Significant correlations between the rate of fecundity and any of the flowering traits could not be found. Years with high fruit-production do not coincide with years of great number of inflorescences. Thus, the number of inflorescences measured in any one year can not be used as a substitute for reproductive performance measurements. Years with high fruit-set may be able to insure long-term survival of the population.

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Four populations of Saponaria bellidifolia situated at the species’ northern range periphery (Apuseni Mountains, southeastern Carpathians) were monitored over a period of 5 years. They were chosen to represent different habitat types (rocky, fixed screes, open screes and grassy), disturbance regime (fire), and population sizes (categorized as large and small). The reproductive effort was quantified, and matrix models were used to describe the population dynamics and to assess population viability. Saponaria bellidifolia had very stable population dynamics in the harsh and stable abiotic conditions of the outcrops where populations occur. Habitat conditions exerted a notable influence on the species’ population reproductive performance, growth rate, and vital rates, whereas population size and climate did not have a clear‐cut effect on the dynamics of the species. Saponaria bellidifolia maintains viable populations in the southeastern Carpathians, at its northern range periphery.

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The grass species Cleistogenes serotina (L.) Keng, generally found in the mountainous region in Hungary, has been observed in the lowlands of the Great Hungarian Plain in the last few decades. Since its first recent mention in sand habitat as well it, has been found in several locations in the interfluve between the Danube and the Tisza. In certain, sandy grasslands, the invasion of this species is considerable (e.g. near Fülöpháza the area invaded by Cleistogenes increased almost fourfold within six years). The success of invasion on new habitats is related to changes in thecharacteristics of plants comparatively studied on mountain and sand populations.We studied blades of leaves on different levels (1st, 5th and 10th) and from different biotops. Cuttings were made, with a thickness of 10-12 μm, at the middle of the blades. The cross sections were observed using a light microscope. Digitised images (DigitPlan) and survey data were arranged into a database.The leaf structure is characterised by the kranz anatomy, and a double layered bundle sheath, which is typical of the aspartate type of C4 grasses. There were significant differences only in cross section area and the number of bundles for various ages of the leaves. There were more bundles in the older leaves than in the younger ones. We did not find any difference in the ratio of tissues among leaves of different ages and sources. According to our study, the ratio of leaf tissues characteristic to species was neither significantly influenced by the biotop, nor by the age of the leaves. However, there is a difference in tissues size. Summarising the results, the species can be considered „only” as ecotypes on thedifferent studied areas. Our new result is that kranz anatomy can also be found in the leaf-sheath.This research was supported by the Hungarian Scientific Fund (OTKA), grant No. T016511 and T026346.

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