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Environmental toxicants such as insecticides are able to provoke epigenetic alterations which can be inherited to future generations. The aim of the current study was to assess whether the insecticide Trebon 10F (containing the active ingredient etofenprox) causes multigenerational and/or transgenerational effects on the egg traits of the collembolan Folsomia candida. The parent generation was kept in soil treated with three concentrations of the insecticide. The hatched offspring from each treatment were divided into two groups and were treated in the same manner as their parents (multigenerational effect), or remained untreated (transgenerational effect). The parents reacted with smaller eggs to the insecticide in a concentration dependent manner. Both multigenerational and transgenerational effects were detected in the offspring generations. While neither the number of eggs nor the ratios of the egg diameters (shortest/longest diameter) changed, the egg size increased as the Trebon 10F concent...

Predatory invertebrates play a significant role in the organisation of aquatic communities. However, their ecology is poorly known even for many common taxa. We examined the meso-habitat use and aspects of movement activity of two common predatory water bug species Ilyocoris cimicoides (L., 1758) and Nepa cinerea L., 1758 under field and laboratory conditions in order to assess the effect of the patchiness on habitat choice. Ilyocoris cimicoides preferred open habitats, rich in submerged vegetation, without submerged terrestrial materials. Shaded habitats such as under trees, with moderately dense vegetation and submerged branches, were favoured by N. cinerea. Both laboratory and field data indicated differences in the short-term and similarity in the long-term movement behaviour of the two species. In the short-term, I. cimicoides moved frequently, while N. cinerea moved rarely, but the distance visited over the course of a longer time span is comparable.

Ringing databases of the EURING Data Bank and the Hungarian Bird Ringing Centre were analysed in order to investigate the philopatry of the great reed warbler (Acrocephalus arundinaceus) in three European regions. The aim of the study was to find out if there are continent-scale geographic trends in philopatry with respect to the age of the birds. Three clusters were assigned according to their geographic positions: (i) southern part of Europe (Region 1: between 36°–43° latitudes), (ii) middle part of Europe (Region 2: between 43°–49° latitudes) and (iii) northern part of Europe, (Region 3: between 49°–56° latitudes). No significant differences were found between the natal and breeding philopatry in any Regions, except Region 3. The birds ringed as adults in Region 3 were less faithful to their breeding site than those of the other two regions. Natal philopatry of juveniles did not differ between Region 1 and Region 2, but both of them differed in this respect from Region 3. A method for choosing appropriate breeding periods in philopatry studies is also proposed.

Detailed faunistic data originating from four sampling series of aquatic Heteroptera (Nepomorpha) in the Lake Balaton (the largest shallow lake of Central Europe) between 1928 and 2002 were analysed. A comparative analysis confirmed that the aquatic bug fauna of this great lake can be established with suitable accuracy if it is sampled by different but devoted collectors. So far 26 species of aquatic bugs have been reported from here. The fauna changed considerably during the seven decades. Species lists of the four basins of the lake established during the four sampling periods show characteristic differences. Not only the frequency of four Micronecta species (Micronecta griseola, M. pusilla, M. scholzi, M. minutissima) changed characteristically but there has been a distinct change in the ratio of rare species too. Rare species were present in significantly higher proportion in the period 1928–1930 than in any of the later samplings between 1984 and 2002. All these changes run parallel with the directio...

In 2003, 26 Heteroptera species (16 aquatic and 10 semiaquatic) were collected from 53 sampling sites in the Szigetkoz region in Hungary. Hyocoris cimicoides and Gerris argentatus were the most frequent aquatic and semiaquatic species, respectively. Large differences both in the species number and species composition were observed among the different flood-prevention areas, arm systems and habitats. Strong negative correlation was found between the average number of aquatic species and current velocity, and a strong positive correlation between the average number of aquatic and semiaquatic species and macrophyte density. From a faunistic point of view, the marsh at Arak is the most interesting and valuable site.

Zn uptake by maize plants may be affected by the presence of arbuscular mycorrhizal fungi (AMF). Collembola often play an important controlling role in the inter-relationship between AMF and host plants. The objective of this experiment was to examine whether the presence of Collembola at different densities (0.4 and 1 individuals g−1 dry soil) and their activity have any effect on Zn uptake by maize through the plant–AMF system. The presence of the AMF (Glomus intraradices) and of the Collembola species Folsomia candida was studied in a laboratory microcosm experiment, applying a Zn exposure level of 250 mg kg−1 dry soil. Biomass and water content of the plants were no different when only AMF or when both AMF and Collembola were present. In the presence of AMF the Zn content of the plant shoots and roots was significantly higher than without AMF. This effect was reduced by Collembola at both low and high density. High densities of Collembola reduced the extent of AMF colonization of the plant roots and hyphal length in the soil, but low densities had no effect on either. The results of this experiment reveal that the F. candida–G. intraradices interaction affects Zn uptake by maize, but the mechanisms are still unknown.

A basic knowledge of regional faunas is necessary to follow the changes in macroinvertebrate communities caused by environmental influences and climatic trends in the future. We collected all the available data on water bugs in Hungary using an inventory method, a UTM grid based database was built, and Jackknife richness estimates and species accumulation curves were calculated. Fauna compositions were compared among Central-European states. As a result, an updated and annotated checklist for Hungary is provided, containing 58 species in 21 genera and 12 families. A total 66.8% of the total UTM 10 × 10 km squares in Hungary possess faunistic data for water bugs. The species number in grid cells numbered from 0 to 42, and their diversity patterns showed heterogeneity. The estimated species number of 58 is equal to the actual number of species known from the country. The asymptotic shape of the accumulative species curve predicts that additional sampling efforts will not increase the number of species currently known from Hungary. These results suggest that the number of species in the country was estimated correctly and that the species accumulation curve levels off at an asymptotic value. Thus a considerable increase in species richness is not expected in the future. Even with the species composition changing the chance of species turn-over does exist. Overall, 36.7% of the European water bug species were found in Hungary. The differences in faunal composition between Hungary and its surrounding countries were caused by the rare or unique species, whereas 33 species are common in the faunas of the eight countries. Species richness does show a correlation with latitude, and similar species compositions were observed in the countries along the same latitude. The species list and the UTM-based database are now up-to-date for Hungary, and it will provide a basis for future studies of distributional and biodiversity patterns, biogeography, relative abundance and frequency of occurrences important in community ecology, or the determination of conservation status.