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A comparative study was undertaken to adopt and evaluate a radiocarbon (14C) preparation procedure for accelerator mass spectrometry (AMS) measurements of cremated bones at our laboratory, including different types of archaeological samples (cremated bone, bone, charcoal, charred grain). All 14C analyses were performed using the EnvironMICADAS AMS instrument at the Hertelendi Laboratory of Environmental Studies (HEKAL) and the ancillary analyses were also performed at the Institute for Nuclear Research (ATOMKI). After the physical and chemical cleaning of cremated bones, CO2 was extracted by acid hydrolysis followed by sealed-tube graphitization and 14C measurement. The supplementary δ13C measurements were also performed on CO2 gas while FTIR was measured on the powder fraction. Based on the FTIR and 14C analyses, our chemical pretreatment protocol was successful in removing contamination from the samples. Good reproducibility was obtained for the 0.2–0.3 mm fraction of blind-tested cremated samples and a maximum age difference of only 150 yr was found for the remaining case studies. This confirms the reliability of our procedure for 14C dating of cremated bones. However, in one case study, the age difference of 300 yr between two cremated fragments originating from the same urn shows that other processes affecting the cremated samples in the post-burial environment can substantially influence the 14C age, so caution must be exercised.

This study summarizes the results of radiocarbon dating and age-depth modelling in four mountain lakes (Brazi, Gales, Bucura and Lia) in the Retezat Mountains. Altogether 69 AMS 14 C measurements were performed on these deposits, mostly on terrestrial plant macrofossils. In several cases, plant macrofossils, aquatic animal remains (Cladoceran eggs) and bulk sediment were measured from the same depth allowing for the comparison of various sediment components in terms of their dating potential. Age-depth models were developed using both Bayesian modelling with the BACON and smooth spline curve fitting with the CLAM software. In this study Bayesian models are applied to identify outlier 14 C dates, while smooth spline models are used to model sediment accumulation age-depth relations, as these are more likely to follow natural deposition time changes of lake sediments. Changes in sediment deposition times (DT) in relation to catchment size and climate are also studied. DT varied considerably in the late glacial (LG) part of the records. The sediment sequence characterised by high deposition rates during the late glacial (DT maximum around 100–110 years cm −1 ) was defined by small catchment size (Lake Brazi, 6 ha; surface area: 0.5 ha). In contrast, much slower LG sediment deposition in the southern slope lake characterised by large catchment area (Lake Lia, 171 ha, 20 years cm −1 ), principally reflecting strong erosion in these catchment areas at times when vegetation cover was scarce. Holocene was characterised again by variable DT values, but only Lake Gales showed extreme values: 62–110 years between 10,900 and 6050 cal yr BP, followed by much slower sediment deposition in the last 6000 years (av. 29 years cm −1 ). Generally, sediment deposition times were largely dependent on the stability and vegetation cover of the slope in the case of high altitude deep lakes, while lower altitude, shallow lakes showed slower sediment deposition time in the early and mid-Holocene, when summer insolation was higher than today. This reflects that in these shallow lakes in-lake organic production probably increased with summer insolation, which was a significant driver in the rate of deposition.

We tested the effect of urbanization on air pollution based on the chlorophyll-a content of Celtis occidentalis leaves along an urbanization gradient (urban, suburban and rural areas) in Debrecen, Hungary. Chlorophyll-a content of Celtis occidentalis, Acer campestre, and Corylus avellana were compared to test which species is the most useful to study the effects of urbanization. Furthermore, the effects of washing solutions (distilled water, tap water, and rainwater) on chlorophyll-a content of tree leaves were also tested during sample preparation. Chlorophyll-a was extracted from leaf samples with acetone, and it was measured using a spectrophotometer. Along the urbanization gradient, chlorophyll-a content of C. occidentalis leaves was the lowest in the urban area; thus, this species proved to be an effective indicator of anthropogenic emission load. Differences were not significant among species in the suburban and rural areas, where the level of air pollution was moderate. We found that effects of the washing solutions on chlorophyll-a content did not differ significantly from each other. Thus, tap water can be used safely to clean the leaf surface, without significant influence on chlorophyll-a. Our study demonstrated that the chlorophyll-a content of leaves was a useful indicator to assess the level of air pollution.

The reproducibility of extraction of residues from spiked soil samples and from soils containing incurred residues was tested with 14C-labeled test compounds of different physical-chemical properties. Nearly 100% of the compounds added to the sample before extraction could be recovered with an average reproducibility relative standard deviation (CV) of 5.4%. The additional steps of the determination process (cleanup, evaporation, etc.) contributed to the major part of the variability of the results (CV = 10–20%). The incurred residues were most efficiently extracted with acetone for 30 min followed by the mixture of acetone/ethyl acetate 1:1 for additional 30 min. However, they could only be recovered at various extent (64–90% of total residues), underlying the importance of testing the efficiency of extraction. The residues were identified and quantified by gas chromatography applying thermionic detector. The performance parameters of the method complied with the international method validation g...

Background. The Amur sleeper, Perccottus glenii Dybowski, 1877, is the most invasive alien fish species in the native aquatic communities in central Europe. Although the accelerated invasion of P. glenii has been well documented, there is little information on the ecological and growth parameters of non-native populations in this region. The aim of this study was to describe the growth features of the population of P. glenii in a shallow oxbow lake in the Carpathian Basin. Materials and methods. Our study sample consisted of 1239 individuals (628 ♂ + 611 ♀) collected from an oxbow lake near the Tisza River in the same month for three years (2013–2015). The length, weight, age structure, sex-dependent growth rate, and the condition factor of the collected specimens were determined. Results. The sex ratio was 0.49 (♀ ÷ (♀ + ♂)). The standard length and weight of the collected P. glenii specimens ranged from 20.7 to 127.7 mm and from 0.3 to 75.8 g, respectively. The length–weight relations (SL–W) were allometrically negative for the males (W = 3.2 × 10–5SL2.960), females (W = 3.8 × 10–5SL2.921), and both sexes (W = 3.5 × 10–5SL2.940), without significant differences between males and females. According to the length-frequency analysis, five age groups were differentiated. The von Bertalanffy growth models were L∞ = 138.87 mm, k = 0.21, t0 = –0.54 (♂), L∞ = 174.21 mm, k = 0.17, t0 = –0.33 (♀), L∞ = 154.01 mm, k = 0.19, t0 = –0.45 (♂ + ♀). The growth performance parameters were Ф′ = 3.61 (♂), Ф′ = 3.71 (♀), Ф′ = 3.65 (♂ + ♀), respectively. Conclusion. Due to unequal investment in reproduction, there was a significant difference in the growth rate between males and females. The literature data showed that invasive gobies and odontobutids (e.g., P. glenii) exhibit more opportunistic reproduction strategy in newly colonized areas, which may contribute to the invasion success. This strategy (e.g., earlier maturation, longer spawning period, etc.) results in slower growth rate due to energetic trade-off between reproduction and somatic growth. The observed growth rate of invasive Amur sleeper population (especially in the older age groups) was slower than that of native and more established naturalized populations in Eurasia.

We have developed a chromium speciation and preconcentration method with the use of the graphite furnace atomic absorption spectrometry (GFAAS) technique. This method is based on single-drop microextraction (SDME) technique. Nowadays the microextractions have become popular, because low amount of organic solvent needs to be used for the separation. The sample was introduced into the extraction cell with a single chloroform droplet. For the separation and enrichment of chromium species, an ion-pair forming compound was used. After the extraction, the chromium content of the droplet was determined by GFAAS. The analytical sensitivity of the standard SDME technique was improved by increasing the volume of organic phase and by sample recirculation. Because of the increased contact area and the developed extraction device, the stability of droplet was markedly increased. As an application we have determined the Cr(VI) content of sea water by the GFAAS technique using these separation/enrichment methods. Under the optimized extraction conditions, the linear range, detection limit (S/N = 3) and precision (RSD, n = 3) for Cr(VI) were 0.14 – 5.00 μg/L, 0.042 μg/L, and ≤ 3.0%, respectively. The advantages of this method are the following: cost efficiency, the high enrichment of chromium species and easy usage with the GFAAS technique. Therefore the concentration of the chromium species can be determined at the ng/L level.

The involvement of ecological theory in habitat restoration has significantly increased in the past decade. However, despite the fact that the field of restoration ecology has grown academically strong in recent years, there are still visible gaps between the advancing discipline of theoretical ecology and current approaches of habitat restoration. We propose bridging these gaps by linking recent developments in theoretical plant ecology with the main questions every restoration practitioner should ask, namely: Q1) How to identify target species and baseline conditions for restoration of the selected habitat?; Q2) When can one count on spontaneous dispersal and when are additional efforts required for facilitating dispersal of desired species?; Q3) Which factors determine the successful establishment of target species and assembly of target communities?; and Q4) What time-scale needs to be considered for the evaluation of species colonisation and restoration success? Knowledge and experience accumulated in practical restoration can considerably benefit theoretical ecology for example by improving the understanding on (i) temporal changes in community, (ii) species assembly, (iii) species dispersal and establishment and (iv) landscape-scale dynamics of biodiversity. We emphasise that to improve joint thinking of practical restoration and theoretical ecology, restoration-problem-driven theoretical research is necessary. We suggest either (i) to translate and link the current findings of theoretical ecology to restoration strategies; and/or (ii) to summarise practical restoration needs by formulation of questions and testable hypotheses based on theory.

Several hundred tons of windblown dust material are lifted into the atmosphere and are transported every year from Saharan dust source areas towards Europe having an important climatic and other environmental effect also on distant areas. According to the systematic observations of modern Saharan dust events, it can be stated that dust deflated from North African source areas is a significant constituent of the atmosphere of the Carpathian Basin and Saharan dust deposition events are identifiable several times in a year. Dust episodes are connected to distinct meteorological situations, which are also the determining factors of the different kinds of depositional mechanisms. By using the adjusted values of dust deposition simulations of numerical models, the annual Saharan dust flux can be set into the range of 3.2–5.4 g/m2/y. Based on the results of past mass accumulation rates calculated from stratigraphic and sedimentary data of loess–paleosol sequences, the relative contribution of Saharan dust to interglacial paleosol material was quantified. According to these calculations, North African exotic dust material can represent 20–30% of clay and fine silt-sized soil components of interglacial paleosols in the Carpathian Basin. The syngenetic contribution of external aeolian dust material is capable to modify physicochemical properties of soils and hereby the paleoclimatic interpretation of these pedogene stratigraphic units.

To investigate treeline and timberline dynamics in the Retezat Mountains (Romanian Carpathians), late glacial and Holocene sediment sequences from four lakes were studied. The south and north slopes of the mountain range were compared using two lakes from the north flank (Lake Brazi, 1740 m a.s.l. and Lake Gales, 1990 m a.s.l) and two from the south flank (Lake Lia, 1910 m a.s.l. and Lake Bucura, 2040 m a.s.l.). Macrofossil and stomata analyses were performed to assess changes in the local vegetation, supplemented by pollen, charcoal and loss-on-ignition analyses. Our results show that treeline reached Lake Brazi on the northern side during the late glacial (ca. 14,000 cal yr BP) and then Lake Gales between 11,000 and 10,800 cal yr BP. During the early Holocene the upper limit of closed forest, the timberline, reached and passed Lake Brazi and has stayed above it since, but it has never reached Lake Gales at 1990 m a.s.l. The expansion of Larix decidua in the late glacialand early Holocene around Lake Brazi is unique. Stomata and macrofossils of Abies alba are also more abundant in the northern records. On the southern flank, treeline reached Lake Lia at around 12,000 cal yr BP, and was either very close to or at the elevation of Lake Bucura between ca. 8600 and 3000 cal yr BP. Timberline reached Lake Lia at ca. 8000 cal yr BP, some 3000 years after Lake Brazi, only 170 m lower on the north slope. Local fire events delayed the advance of timberline around Lake Lia in the early Holocene in a dry continental climate. The surrounding forest was dominated by Picea abies with individuals of Pinus cembra and stands of P. mugo until about 3000 cal yr BP when timberline retreated below the lake. Maximum elevation of timberline was attained between ca. 8000 and 3000 cal yr BP, after which it descended in response to climate cooling. Regional climate change appears to be the main driver of treeline dynamics, but it was modified by local climatic differences due to slope aspect. The first signs of human disturbance appeared ca. 4200 cal yr BP, when naturally open areas were used as alpine pastures. Human impact in the treeline ecotone, mainly burning and grazing, was intensified after ca. 2600 cal yr BP, contributing to the widening of the ecotone and the lowering of the timberline.

1.Floral deception is widespread in orchids, with more than one third of the species being pollinated this way. The evolutionary success of deceptive orchids is puzzling, as species employing this strategy are thought to have low reproductive success (less flowers yielding fruits) because of low pollination rates. However, direct measurements of total seed production in orchids – which is a better measure of reproductive success – are scarce due to the extremely small size of their seeds. 2.Here, we quantified seed numbers in 1,015 fruits belonging to 48 orchid species from the Pannonian ecoregion (central Europe) and obtained fruit-set and thousand-seed weight data for these species from the literature. We used phylogenetic comparative methods to test the hypothesis that deceptive species should compensate for their lower fruit-set by having either more flowers, larger seeds or more seeds in a fruit. 3.Similarly to previous studies, we found that deceptive orchids have substantially lower fruits-set than nectar-rewarding ones. Also, we found that deceptive species have more seeds in a fruit but not more flowers or larger seeds compared to nectar-rewarding ones. Based on our results, deceptive species compensate for their lower fruit-set by having higher seed numbers per fruit. As a consequence, their seed numbers per shoot do not differ from that of nectar-rewarding ones. 4.Together with other benefits of deceptive pollination (e.g. lower energy expenditure due to the lack of nectar production and higher genetic variability due to decreased probability of geitonogamous pollination), our results can explain why deceptive strategies are so widespread in the orchid family. 5.Synthesis. Our results indicate that deceptive orchids can compensate for their lower fruit-set by having more (but not larger) seeds in a fruit than rewarding species. These findings highlight possible ways in which plants can increase their reproductive success in face of pollinator limitation. We emphasize that fruit-set in itself is an inappropriate measure of the reproductive success of orchids – the total number of seeds per shoot is a much better approximation.

The gut contents of filter-feeding fish often contain considerable amounts of viable phytoplankton cells; thus, these animals can act as vectors in the horizontal and vertical transport of algae. In this study, the potential role of the introduced filter-feeding Asian carps (hybrids of silver carp Hypophthalmichthys molitrix and bighead carp H. nobilis) in algal dispersion was studied in the oligo-mesotrophic Lake Balaton (Hungary). We examined the algal composition in the lake water, gut contents (foregut and hindgut), and occasionally in the filtered suspensions collected directly from the gill rakers (filtering apparatus) of fish. Microscopic analyses revealed that the phytoplankton composition of the ingested food differed considerably from what we found in the lake water. Cryptophytes, dinoflagellates, and euglenophytes were observed in both the lake water and foregut samples but were absent in the hindgut samples. However, in the cultured hindgut samples, we found viable cells of several phytoplankton taxa (e.g., diatoms, blue-greens, desmids, volvocalean and chlorococcalean green algae), which managed to survive the physical and chemical digestion. These results imply that the presence of these filter-feeding fish can alter the phytoplankton species composition and promote the dominance of taxa that are able to resist digestion.

Comprehensive atmospheric studies have demonstrated that carbonaceous particles are one of the main components of atmospheric aerosols over Europe. The aim of our study was to establish an automated elemental analyser interfaced to a stable isotope mass spectrometer (EA-IRMS) method at the Hertelendi Laboratory of Environmental Studies (HEKAL), as a suitable method of quantification of total carbon mass in individual PM2.5 aerosol samples. Total carbon (TC) mass and simultaneous stable isotopic ratios were determined for both test standard and genuine aerosol samples. Finally, the results were compared to the ones obtained independently by an alternative sealed tube combustion method developed previously at HEKAL. The TC recovery tests of standard material prepared by the sealed tube method confirmed at least a carbon recovery yield of 92% for a broad range of carbon mass (100–2000 μg). The stable isotopic results confirmed that sealed tube method is reproducible and suitable to be used as a reference to verify our new EA-IRMS method. The EA-IRMS TC measurements of genuine aerosols gave on average 3% higher carbon recovery yield, relative to the uncorrected results of the sealed tube method. The comparison of the stable isotopic results by the two methods for aerosols also showed minimal differences. Consequently, the possibility of simultaneous TC and stable isotopic analyses makes the EA-IRMS method a very attractive alternative for continuous measurement of aerosols, with an accuracy and reliability similar to other commercial devices.

Remains of aquatic biota preserved in mountain lake sediments provide an excellent tool to study lake ecosystem responses to past climate change. In the PROLONG project a multi-proxy study was performed on sediments of glacier-formed lakes from the Retezat Mountains, Southern Carpathians (Romania). The studied lakes (Lake Brazi and Gales) are situated on the northern slope of the mountain at different altitudes (1740 m and 1990 m a.s.l.). Our main objectives were 1) to describe the main limnological changes in these lakes during the last ca. 15,000 years and 2) to summarize the environmental history of the studied lakes based on taxonomical and functional patterns of the biological proxies. For this synthesis we used the results of diatom and chironomid analyses, and indirect biotic and abiotic parameters, including sediment organic matter (LOI) content, geochemical element concentrations (Al, Ca, S, Sr) and biogenic silica content. Using multivariate numerical approaches we analysed changes in the assemblage structure of siliceous algae and chironomids, compared temporal patterns among proxies, examined the relationship between potential driving factors, chironomid and diatom assemblage changes and identified paleolimnological phases of the lake successions. Changes in assemblage composition and aquatic ecosystem state apparently followed summer insolation, local climatic conditions and local productivity changes driven by these. Diatom and chironomid assemblages generally changed in a similar direction and at a similar time within a lake, but differed to some extent between Lake Brazi and Gales. At both lakes the strongest variations were observed in the Late Glacial and the first half of the Holocene. The strongest Holocene assemblage changes took place in the earliest Holocene in Lake Brazi, but extended into the mid-Holocene in Lake Gales, following long-term insolation changes and climatic changes. In addition, three common zone boundaries were identified: at ca. 14,200 and at ca. 6500 cal yr BP for every records and at ca. 3100 cal yr BP for diatom records in both of the lakes and for the chironomid record of Lake Brazi. This multi-proxy synthesis provides comprehensive data that increase our understanding of the past variability of lake ecosystem functioning and biodiversity in East-Central Europe.

The vertical distribution of soil organic carbon (SOC) with depth and its horizontal pattern is influenced by the topography and relief of the surface, due to lateral redistribution of soil material along slopes. Spatial and temproral variability of these changes is frequently due to human impacts on the landscape. In our study, the results of these processes were studied in detail in a small sub-catchment in a forested hillslope section using radiocarbon (14C) dating of SOC and embedded datable material (charcoal, artifacts) from soil profiles with colluvial accumulations. Events with accelerated material redistribution could be identified as an accumulation of a 40-cm-thick colluvial layer between cal BC 410–360 (2σ) and cal AD 430–580 (2σ). Later colluvial deposition resulted in thinner accumulations (cal AD 1120–1220 [2σ] 30 cm; cal AD 1810–1920 [2σ] 21 cm). As the earliest human impact, we found soil transformation from cal BC 1290–1130 (2σ). The depth-age model for SOC compiled according to the average SOC age and its depth showed different characteristics on middle-slope and down-slope position, with rates of 48.0 yr×cm–1 and 22.0 yr×cm–1 respectively, which indicates the importance of topographic position of soils in SOC redistribution processes.

The Middle to Upper Palaeolithic transition is one of the crucial periods of change in the prehistory of Europe due to the full emergence, continent-wide, of modern human lithic technologies, and detrimental of Neanderthal survival. Knowledge about the transition is growing, however, the evidence for cultural and technological developments for the Middle Palaeolithic in the Carpathian – Lower Danube Basin is still rather sparse. Here we discuss latest findings arising from a chronological investigation of Middle Palaeolithic assemblages within the Varghis karst, Eastern Transylvania, Romania. Combining our first chronological results with information from previous excavations, we can distinguish two main stages of habitation (albeit Middle Palaeolithic lithics and faunal remains appear scattered throughout the investigated profile) within the Abri 122 rock shelter. In order to augment the typological cultural considerations, we applied direct radiocarbon dating on bones and charcoal from within the occupation layers. Radiocarbon dating of bones suggests that the Middle Palaeolithic sequence is older than the upper dating limit of the method, whereas direct luminescence ages on the lowermost productive horizon and immediately above it indicate surprisingly old ages of ca. 106–141 ka (OSL – optically stimulated) or 99–174 ka (IRSL – infrared stimulated). Multiple-protocol dating of charcoal found within the two habitation layers produced ages >38 14 C ka BP, also suggesting that the lowermost lithic-rich horizon pertains to the Middle Palaeolithic industries. Overall, the recovered lithics, currently forming one of the most significant collections for Romania, are fully consistent with two main habitation phases connected to Middle Palaeolithic cultural affinities. The occurrence of a volcanic ash layer within Ursului Cave and originating from the Ciomadul volcanic complex (Carpathians) is first reported here. Recently dated to ∼ ≥ 43 (−50) ka, it might represent an important marker horizon, providing that it is identified within other Palaeolithic cave assemblages.

For risk assessment of potentially toxic element (PTE) pollution of sediments and soils the fractionation by sequential extraction procedures are applied which require longtime leaching-shaking periods to achieve the dissolution equilibria. In this work an attempt is described for reduction the duration these leaching-shaking periods of the sequential extraction procedure proposed by Community Bureau of Reference (BCR) in 1993 by application of ultrasonic treatment. The fractionation of PTE content of BCR 701 certified reference sample was performed in three experiments: “A” experiment was the control, all extraction steps were performed with 16 hours shaking according to the BCR prescription; “B” experiment: in each extraction step was applied 1 hour preliminary ultrasonic treatment and after this 1 hour shaking; “C” experiment: only 1 hour ultrasonic treatment and no shaking was applied. It was experienced that by ultrasonic treatment can be efficiently increased the rate of dissolution when constant temperature of assisting medium was kept. 77% and 63% of element content extractable with the control “A” experiment can be extracted in “B” and “C” experiments, respectively. To achieve the 100% efficiency further experiments are in process.

Novel ecosystems formed by invasive plants provide a good opportunity to get insight into early dynamics and pattern formation of these ecosystems. The invasive black locust as host plant, Bruchophagus robiniae as host-specific seed predator and its parasitoids were the components of the studied tritrophic system. To investigate disturbance-driven dynamics of this system we created seed-vacated host plant patches in a field experiment. We removed all pods from selected patches of black locust resulting in an induced local extinction of seed predators and their parasitoids. We hypothesized that disturbance enhances top-down control by parasitoids; this enhanced top-down control decreases seed predation, facilitating the host plant's spread. We found that disturbance modified only parasitism after controlling with year effect: in vacated patches median parasitism was higher than in control patches. Seed predation exceeded its initial level in vacated patches in the third year after the disturbance, but in the fourth year it dropped again presumably due to the strong top-down control. Our findings also suggested that the seed predator was also affected by the bottom-up control of its host plant's density. We found that in the studied new ecosystem the top-down control was strengthened by the disturbance. Since the host plant of the tritrophic system is an invasive species, partial habitat disturbance of such species may increase the severity of parasitoid top-down control, which may reduce seed predation by the herbivores.

We tested the suitability of Salix viminalis for phytoextraction with the analysis of selected elements in soil, root, and leaf, and by visual tree condition assessment in an area with varying levels of contamination. Bioconcentration factor (BCF) and translocation factor (TF) were used to assess the phytoextraction potential of willows. The middle part of the study area was strongly contaminated, while the northern and southern parts were moderately contaminated. We found increasing element concentrations toward deeper layers. Mean concentrations of elements in roots were similar among the three parts, while in leaves the highest concentrations were found in the strongly contaminated part of the study area. Tree condition scores were the lowest in the strongly contaminated part of the study area, which was caused by Al, Ca, K, Mg, Ni, Sr, and Zn concentration. These elements induced leaf disease and leaf feeders. The highest BCF values were found for Cu, Fe, Mn, and Zn in root, and for Cd and Zn in leaves, indicating that S. viminalis had high accumulation potential of these elements. Furthermore, TF values were high for Cd, Mn, Sr, and Zn. Our results also demonstrated that soil element composition has major influence on the condition of S. viminalis individuals. Furthermore, visual condition assessment was found to be a useful tool to assess the phytoextraction potential of trees.

Previous studies on phytoremediation reported contradictory or inconsistent results on the Cd, Pb, and Zn accumulation in and among plant parts of willow (Salix) species. We hypothesized that metals could accumulate in all plant organs in different concentrations and the metal accumulation in tissues would be increased with exposure time. Furthermore, we analysed the effect of soil pH on metal accumulation, and the correlation between metals. We evaluated published information on Cd, Pb, and Zn accumulation in root, stem, twig, and leaf of willow species using meta-analysis. Results showed that all parts of willow species accumulated significantly more Cd, Pb, and Zn in contaminated soils than in uncontaminated soils. However, the metal accumulation was significantly different among plant parts. We concluded that willow species were proven to be prosperous accumulators of Cd (twigs and leaves), Pb (roots and twigs) and Zn (twigs). We found that Cd accumulation rate in stems is higher in soils with lower pH. Significant positive correlation was found between the accumulations of Cd and Zn in stems. Accumulation rates of Cd (both in leaves and twigs) and Zn (in twigs) were increased significantly with exposure time and the accumulation was successful for at least 3 years.

Pesticide residues were determined in about 120 soil cores taken randomly from the top 15 cm layer of two sunflower fields about 30 days after preemergence herbicide treatments. Samples were extracted with acetone-ethyl acetate mixture and the residues were determined with GC-TSD. Residues of dimethenamid, pendimethalin, and prometryn ranged from 0.005 to 2.97 mg/kg. Their relative standard deviations (CV) were between 0.66 and 1.13. The relative frequency distributions of residues in soil cores were very similar to those observed in root and tuber vegetables grown in pesticide treated soils. Based on all available information, a typical CV of 1.00 was estimated for pesticide residues in primary soil samples (soil cores). The corresponding expectable relative uncertainty of sampling is 20% when composite samples of size 25 are taken. To obtain a reliable estimate of the average residues in the top 15 cm layer of soil of a field up to 8 independent replicate random samples should be taken. To obtain better estimate of the actual residue level of the sampled filed would be marginal if larger number of samples were taken.

Classifying benthic diatom taxa based on ecological and morphological features became increasingly important in recent years due to the demand of understanding the dynamics and functioning of diatom assemblages. The great potential in using these functional classifications in diatom ecology involves further refinement of current classification. In our experimental study, colonisation processes of diatom assemblages were studied in a typical small lowland stream, using both diatom guilds and cell size categories. We also tested newly proposed combined eco-morphological functional groups (ecological guilds combined with cell size categories) in the study of the colonisation process in benthic diatom assemblages. We hypothesised that (i) there is a decrease in the proportion of low profile guild, while an increase in that of high profile and motile guilds in time with the decreasing rate of physical disturbance; (ii) the presence of small size categories will be pronounced at the beginning of the colonisation processes, while proportion of larger size categories will be higher in the latter phases of colonisation; and (iii) the relationship between taxa and environmental factors are better reflected by the use of combined eco-morphological functional groups than by the sole analyses of rough guilds or cell size categories. The first hypothesis was not confirmed, and our second hypothesis was only partially confirmed by the results. We found that the relationship between environmental factors and guilds, as well as cell size categories was not appropriate to reveal the relationship between abiotic factors and taxa composition. In contrast we found that compositional changes in colonisation were appropriately reflected by the newly defined combined eco-morphological functional groups. In the combined eco-morphological functional groups, such kind of taxonomical and ecological features can be prevailed which are hidden in guilds or cell size categories separately. Thus these combined eco-morphological functional groups could help to come one step closer to develop a widely used ecological classification in diatom researches.

The final product of a post-volcanic activity is the exhalation of low-temperature (2 spas. Along its pathway to the surface, the deep origin gas also intakes different radon isotopes from the rocks and soils; therefore, the risks associated with radon exposures should also be a concern. In this work, we have found that the 222Rn activity concentration in the mofette gas of Mátraderecske is particularly high; it is in the order of 200 kBq·m−3. However, owing to the carefully designed flow pattern of mofette gas and fresh air, the radon level is about 1 kBq·m−3 at the breath level of the staff, accompanying the treatment, which is the radon reference level for workers in Hungary. We have also found that in this dry spa, radon is a good tracer of CO2; therefore, it can be used to monitor the CO2 distribution in the treatment pools.

The planning of the correct channel reconstruction is a priority in the rehabilitation of regulated surface streams. The present study examines the most important morphological and ecohydrological factors of a highly modified watercourse. A comparative analysis was performed among modelled and measured morphological, river geometrical, hydraulic, and vegetation status indicators. Reduction of data redundancy and examination of the relationships was done by factor analysis. This was found during the data reduction to six or seven attributes (component) and it was sufficient for imaging the original information content. There are mathematically derived hydrological background variables that are extremely significant in characterizing the watercourses, for example; the Reynolds number, Froude number, ratio of slope Froude-number, speed-to-depth ratio, depth-to-width ratio, etc. The partially regulated and artificial river sections were numerically separated from each other in the analysis. The functional aquatic plant habitats and Manning’s n Roughness have got a higher factor weight in the less regulated river section, than in artificial stage. The weakest factor weights were those status indicators which were most changed by the regulations. The results provide support for defining and monitoring the required environmental geometric riverbed interventions.

Urbanization and anthropogenic activities are the major source of environmental pollution which may cause damage in terrestrial ecosystems and their organisms. Toxic elements can accumulate in soil and leave tissue; thus, through the food chain they can accumulate in predatory organisms. The aim of our study was to investigate the effects of urbanization on toxic element concentration in soil, leaf litter and Carabus violaceus and Pterostichus oblongopunctatus specimens along an urbanization gradient. The studied predator species were common and their distribution is widespread along the urbanization gradient. Soil, leaf litter and ground beetles were collected from three forested area: urban park, suburban forest and rural forest. The following toxic element concentrations were analyzed in all samples: Al, Ba, Cd, Cu, Fe, Mn, Ni, Pb, Sr and Zn. In the soil there was no significant difference in toxic element concentration between areas, except in seasons. Significantly higher toxic element concentration was found in autumn than in spring in the soil. In the case of leaf litter we found significant differences between areas in the following toxic elements: Ba, Cu, Mn, Sr and Zn. The concentrations of all elements were significantly higher in autumn than in spring. Significantly higher concentration was found in P. oblongopunctatus specimens than in C. violaceus for all studied elements, except Sr. We found significant differences in elemental concentrations between sexes in both species. Significantly higher Cu and Pb concentration was found in male beetles than in female ones. Just the opposite was true for the Sr concentration. We found positive correlation between toxic element concentration of C. violaceus and leaf litter for Mn and Zn. Negative correlations were found between toxic elements of ground beetles and soil for Al, Ba, Fe, Sr and Zn. Our study confirms that different breeding strategies and sexes cause differences in the accumulation of toxic elements. In summary, we demonstrated that ground beetles, leaf litter and soil were suitable bioindicators for monitoring the effects of urbanization and anthropogenic activities on terrestrial ecosystem.

The introduced black locust (Robinia pseudoacacia) has become an invasive plant species in Europe. The introduction of alien plants such as the black locust may modify ecosystem composition and functioning. In response to the presence of a potential host plant, herbivores can adapt and shift to the consumption of the new host plant. In Eastern-Central Europe, the seed predator Bruchophagus robiniae (Hymenoptera: Eurytomidae) is an important consumer of black locust seeds which presumably shifted from its formerly host species to black locust. We tested the influence of host plant abundance on a seed predator – parasitoid community. We found that the seed predator B. robiniae was present in higher numbers in woodlots than in small patches of black locust. The density of the specialist parasitoid Mesopolobus sp. was lower in woodlots than in small patches, while the generalist parasitoid Eupelmus urozonos was evenly distributed between woodlots and small patches of black locust. We found that parasitoid species are influenced by the patch size of host plants, thus characteristics of introduced host plants can also manifest in higher trophic levels.

In the section above Tiszaújlak, despite the presence of embankments, the River Tisza shows active meandering tendency and it splits into branches resulting in side channels, dead channels and backwaters that follow the main channel. In our work we examined the right- and the left-side riverbank sections of the River Tisza, between Tiszaújlak (Вилок) and Tiszasásvár (Тросник), as well as between Tiszaújlak and Tiszapéterfalva (Пийтерфолво), to reveal the extent of bar depositions between 2006 and 2015, and to what extent the intensity and direction of the riverbank formation processes were influenced by the material of the bank and the plant coverage, its rate and characteristics. We tried to reveal which sections were eroded by the river and what security risks they have for the safety of the settlements along the Tisza River. On the right side of the Tisza River riverbank 51, and on the left side 62 main measuring points were recorded by GPS positioning satellite in 2009, 2010 and 2015. Our results were compared to the satellite images of Google Earth taken in 2006, too. According to our experience, in several bends of the examined sections of the river, active bar deposition can be observed; in some cases more than 100 m of bar depositions were detected.

Free grazing and herding of local breeds have a long tradition in management and conservation of extended grassland habitats such as alkali steppes. However, there is a lack in studies evaluating the effects of grazing types and regimes on the vegetation composition and functional diversity. We selected Artemisia steppes, a widespread type of alkali steppes, to study the changes of vegetation composition and diversity along a grazing intensity gradient. We recorded the cover of vascular plant species, in altogether 150, 2 × 2-m-sized plots of 15 steppes in 2014. The steppes were managed by free grazing, traditional Hungarian Grey cattle grazing (low, moderate and high intensity), or by heavy grazing (Grey cattle and sheep, and additional donkey grazing). We answered the following questions: (i) How do the species richness, diversity and species evenness change along the increasing intensity of grazing? (ii) How does the grazing affect the functional trait composition along the intensity gradient? (iii) How similar is the composition and diversity of free grazed steppes to the pastoral grazed ones? We detected no significant differences in species richness but a humped-back curve with a peak at the medium grazing intensity was found for the Shannon diversity, evenness and the proportion of subordinated target species. The highest Rao’s quadratic entropy was found for low intensity grazing. The lowest scores of multi-trait functional evenness were detected for the medium grazing intensity, while for multi-trait functional divergence both medium and very high intensity displayed low scores. The intensity of grazing was negatively correlated with the plant height and LDMC, while positively with the rosette forming, SLA, thousand-seed weights, terminal velocity and flowering period. Our results suggest that for the highest functional diversity a low intensity traditional cattle grazing is recommended. A medium grazing intensity should be chosen to have the highest proportion of subordinated target species of conservation interest, and the highest species diversity and evenness. Our findings suggest that free grazing and low-intensity traditional grazing can be substitutive to each other; various grazing intensities from low to medium, alternating in space and/or time can be appropriate to maintain high compositional diversity.

In recent years measurable concentrations of non-steroidal anti-inflammatory drugs (NSAIDs) have been shown in the aquatic environment as a result of increasing human consumption. Effects of five frequently used non-steroidal anti-inflammatory drugs (diclofenac, diflunisal, ibuprofen, mefenamic acid and piroxicam in 0.1 mg ml(-1) concentration) in batch cultures of cyanobacteria (Synechococcus elongatus, Microcystis aeruginosa, Cylindrospermopsis raciborskii), and eukaryotic algae (Desmodesmus communis, Haematococcus pluvialis, Cryptomonas ovata) were studied. Furthermore, the effects of the same concentrations of NSAIDs were investigated in natural algal assemblages in microcosms. According to the changes of chlorophyll-a content, unicellular cyanobacteria seemed to be more tolerant to NSAIDs than eukaryotic algae in laboratory experiments. Growth of eukaryotic algae was reduced by all drugs, the cryptomonad C. ovata was the most sensitive to NSAIDs, while the flagellated green alga H. pluvialis was more sensitive than the non-motile green alga D. communis. NSAID treatments had weaker impact in the natural assemblages dominated by cyanobacteria than in the ones dominated by eukaryotic algae, confirming the results of laboratory experiments. Diversity and number of functional groups did not change notably in cyanobacteria dominated assemblages, while they decreased significantly in eukaryotic algae dominated ones compared to controls. The results highlight that cyanobacteria (especially unicellular ones) are less sensitive to the studied, mostly hardly degradable NSAIDs, which suggest that their accumulation in water bodies may contribute to the expansion of cyanobacterial mass productions in appropriate environmental circumstances by pushing back eukaryotic algae. Thus, these contaminants require special attention during wastewater treatment and monitoring of surface waters.

The Upper Tisza floodplain region provides a mosaic of aquatic habitats including a series of oxbows. Inorganic contaminants can accumulate in the sediment; thus, the sediment is good indicator of the contamination of these oxbows. Our aim was to explore the effects of anthropogenic activities on the concentration of elements and also to study the influence of vegetation types on the element in surface sediment of oxbows. We studied eight oxbows: two of them were protected, four of them were used for fishing and two of them were contaminated with domestic sewage. The following elements were measured with MP-AES in surface sediment: Al, Cr, Cu, Fe, Mn, Pb and Zn. The elemental concentration was compared to the toxicity classes of Environmental Protection Agency (EPA), and the assessment of the level of toxicity was based on this comparison. We found that studied oxbows were different from each other based on the elemental concentrations of sediment using canonical discriminant analysis and analysis of variance. Based on the elemental concentration in surface sediment of oxbows, separation was also found among vegetation types. But significant difference was not found in the concentrations of elements based on vegetation types. Our results demonstrated that the anthropogenic activities had remarkable effects on the elemental concentration of surface sediment in oxbows. Our findings suggest that the sediment is useful to assess the effects of anthropogenic activities on elemental concentrations of oxbows.

The serious oak decline was reported for the 1979-80 period and 63.0% of adult oaks died in a mixed oak forest in the Sikfőkut site, Hungary. The data were used to obtain (1) quantitative information on diversity indices of shrub layer and shrub canopy, including foliage cover percentage of the shrub layer, mean cover of shrub species before and after the oak decline and (2) structural information on shrub basal area and shrub foliage arrangement. Since 1972 we have determined diversity indices, cover percentage and basal area of shrubby vegetation on the monitoring and plus plots. A negative relation was detected between Shannon-Wiener and Evenness indices of the shrub layer and living oak tree density. A positive relation was confirmed between basal area and mean cover of dominant woody species (Acer campestre, Acer tataricum and Cornus mas). The mean cover of shrub species except of A. campestre increased non-significantly after the oak decline on the 48 m × 48 m plot. The findings of the study indicate that diversity indices of the shrub layer and mean cover of A. campestre can be used as a principal indicator of natural disturbance in the studied mature stand and the species of the shrub layer respond differently to the decreasing stand density.

Terrestrial isopods and millipedes, members of the invertebrate macro-decomposer guild, were collected through pitfall traps in three Swiss cities (Zurich, Lucerne, Lugano). A total of 7,198 individuals of 17 isopod species (7093 ind.), and 10 millipede species (105 ind.) were captured. Besides the Alpine endemic isopod (Trichoniscus alemannicus) and millipede (Cylindroiulus verhoeffi), urban assemblages were mainly composed of widespread, native European and even cosmopolitan species, which are frequent in anthropogenic areas. Overall species richness (isopods and millipedes combined) was similar in Zurich (17 species) and Lucerne (16), while only 13 species were sampled in Lugano. According to the Sørensen index of similarity, species composition of Zurich and Lucerne were more alike, while the one of Lugano was more distinct from the other two cities.This result can be explained by the spatial proximity of Zurich and Lucerne in the north of the Alps compared to Lugano, which is located more distantly and in the south of the Alps. Dominant isopods and millipedes in Zurich and Lucerne were found to be widespread synanthropic species in temperate Europe (Porcellio scaber, Trachelipus rathkii and Ophyiulus pilosus) while the dominant isopod in Lugano (Trachelipus razzautii) is a species with a north-eastern Mediterranean distribution. Our study reveals that the urban millipede and isopod fauna in Swiss cities mainly consists of widespread species, but species of narrower distribution (e.g. T. alemannicus, C. verhoeffi ) may also find suitable habitats in cities. Despite some signs of biotic homogenization, our study also found compositional differences of millipede and isopod assemblages between northern and southern cities that suggest geographical effects of the regional species pool.

Past and present pressures on forest resources have led to a drastic decrease in the surface area of unmanaged forests in Europe. Changes in forest structure, composition, and dynamics inevitably lead to changes in the biodiversity of forest-dwelling species. The possible biodiversity gains and losses due to forest management (i.e., anthropogenic pressures related to direct forest resource use), however, have never been assessed at a pan-European scale. We used meta-analysis to review 49 published papers containing 120 individual comparisons of species richness between unmanaged and managed forests throughout Europe. We explored the response of different taxonomic groups and the variability of their response with respect to time since abandonment and intensity of forest management. Species richness was slightly higher in unmanaged than in managed forests. Species dependent on forest cover continuity, deadwood, and large trees (bryophytes, lichens, fungi, saproxylic beetles) and carabids were negatively affected by forest management. In contrast, vascular plant species were favored. The response for birds was heterogeneous and probably depended more on factors such as landscape patterns. The global difference in species richness between unmanaged and managed forests increased with time since abandonment and indicated a gradual recovery of biodiversity. Clearcut forests in which the composition of tree species changed had the strongest effect on species richness, but the effects of different types of management on taxa could not be assessed in a robust way because of low numbers of replications in the management-intensity classes. Our results show that some taxa are more affected by forestry than others, but there is a need for research into poorly studied species groups in Europe and in particular locations. Our meta-analysis supports the need for a coordinated European research network to study and monitor the biodiversity of different taxa in managed and unmanaged forests.

International audience; Halting the loss of biodiversity comes along with the need to quantify biodiversity composition and dynamics at large spatial and temporal scales. Highly standardized, international monitoring networks would be ideal, but they do not exist yet. If we are to assess changes in biodiversity now, combining output available from ongoing monitoring initiatives is the only option. However, integration of biodiversity information across schemes is still very poorly developed. In this paper, we outline practical issues to be considered when planning to combine existing monitoring information. First, we provide an overview of avenues for integration along the four dimensions that characterize a monitoring design: sample size, biological coverage, spatial coverage and temporal coverage. We also emphasize that complementarity in monitoring targets across schemes enables to describe complex processes of biodiversity dynamics, e.g. through relating species traits to the impacts of environmental changes. Second, we review some methods to overcome differences in designs among monitoring schemes, such as site selection, post-stratification and measurement error. Finally, we point out some commonly used statistical methods that are at hand for combining data or parameter estimates. We especially emphasize the possible levels of data integration (raw data, parameter estimates, or effect size estimates), and the largely under-exploited potential of meta-analysis methods and weighted analyses. This contribution aims to bolster the practice and use of integration of ongoing monitoring initiatives for biodiversity assessment.