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Interactions between the elements N, Cu and Mo were studied on rape in 2000 in a field experiment set up on chernozem loam soil with lime deposits. The ploughed layer of the soil contained 3% humus, around 5% CaCO3 and around 20% clay. Soil analysis showed that the area was well supplied with Ca, Mg, K and Mn, had satisfactory Cu content, but was only poorly or moderately supplied with P and Zn. The groundwater depth was 13–15 m and the area was prone to drought. The experiment was originally set up in a split-plot design with 4N × 3Cu = 12 treatments in three replications, giving a total of 36 plots. The N rates, applied as calcium ammonium nitrate, were 0, 100, 200 and 300 kg ha−1 and the Cu rates, in the form of CuSO4, were 0, 50 and 100 kg ha−1. In the 5th year of the experiment the 15 m long plots were halved and the two half-plots were separated by a 1 m path. The experiment thus became a strip-split-plot design, consisting of 4N×3Cu×2Mo = 24 treatments in three replications, giving a total of 72 plots. The 48 kg ha−1 Mo was applied in the form of (NH4)6Mo7O24·4H2O. The generative phases of flowering and ripening were characterized by drought and depression. The main results were as follows:
Cadmium accumulation in soils causes ecological, biological and human health risks. Previous studies have shown that reductions in the shoot height and fresh biomass of ryegrass (Lolium perenne L.) are a sensitive indicator of the cadmium pollution level in soils.
Four soils with different types and properties were included in the experiment. In the first period of the biotest, 2 g cotton-wool pads moistened with distilled water were planted with 2 g of perennial ryegrass seeds and the seedlings were grown for 6 days. On the 7th day the cotton-wool pads containing the seedlings were placed on soils polluted with four levels of cadmium: 0, 1, 2 and 4 mg Cd kg−1 soil, added to the soil in the form of cadmium acetate. After a first nutrient-deficient period, the seedlings took up nutrients and toxic substances intensively from the soil samples. After a 14-day period of soil–plant contact the fresh biomass, dry biomass and Cd concentration of the shoots were measured, in addition to which the shoot height was measured every 2 days.
Cadmium treatment significantly reduced the shoot height and fresh weight of ryegrass in all the tested soils, and the damaging effect was proportional to the applied dose. A reduction of more than 10% in the shoot height and fresh weight were observed even at a Cd pollution level of 1 mg Cd kg−1 soil. At the highest Cd level the decrease in shoot height was more than 40% and the decrease in fresh weight more than 35% in all the soils.
The increasing level of Cd application significantly increased the Cd concentration of the shoots. More Cd was accumulated in ryegrass shoots on soils with low pH and low organic matter content.
The results indicate that the ryegrass biotest method is suitable for the characterization of Cd contamination in different soils.
The particle size distribution (PSD) values obtained for a soil database representing the main Hungarian soil types using the Hungarian standard (MSZ-08-0205-78) and the international standard (ISO/DIS 11277:1994) were compared with the pipette method. The relationship between these PSDs and other physical soil characteristics (upper limit of plasticity according to Arany, water vapour adsorption according to Sík) was also analysed, and a suggestion was made of how these results could be converted into each other.
Experience showed that the pre-treatments applied as part of the ISO/DIS method may change the ratio of particle size fractions: there was a significant increase in the clay content, while the silt content decreased to a lesser and the sand content to a greater extent, possibly because some of the particles remain in microaggregate form when the MSZ method is used. The results confirmed the greater accuracy of the ISO/DIS method: the clay contents measured with the ISO/DIS method exhibited stronger correlations with the upper limit of plasticity according to Arany and with hygroscopicity values than those measured with the MSZ method.
The estimated ISO/DIS fractions became much closer to the measured ones when the suggested pedotransfer functions were applied. The conversion method proved to be more reliable for the prediction of clay and sand content than for silt content. In its present form the estimation method is not suitable for replacing the ISO/DIS method, but it could be of good service in research and comparative analysis in cases where only the MSZ method can be used or where only old MSZ PSD data exist.
Agricultural utilisation is one of the most promising uses of sewage sludge in Hungary. Sewage sludge can be applied to agricultural fields in two ways: the injection of dewatered sewage sludge and the application of sewage sludge after composting. Vermicomposting is a special type of composting, where the organic residues are broken down by earthworms. The worms facilitate the decomposition process both by mixing the sludge and by physically degrading it. Earthworm species have various morphotypes requiring different habitats. Compost worms have great adaptability to extreme conditions and are capable of exploiting organic matter in a state of decomposition. Eisenia sp., Eudrilus eugeniae and Perionyx excavatus are important species for vermicomposting.
When examining the role and possibilities of vermicomposting, it is important to compare it with traditional composting methods.
The most important aspect of producing vermicompost is to ensure optimum environmental conditions for the earthworms, especially in terms of temperature, humidity and aeration, which requires constant attention.
An important feature of traditional composting is the thermophilic phase, during which the pathogenic organisms in sewage sludge are destroyed. The thermophilic phase is omitted during vermicomposting due to the thermal sensitivity of the earthworms, but the presence and activity of the earthworms results in similar sterility.
Regarding its nutrient content, vermicompost contains larger quantities of total and plant-available macroelements than conventional composts. A further advantage is the presence of the plant hormone agents excreted by earthworms.
From the environmental point of view, the ability of earthworms to accumulate heavy metals and the role of their special gut flora in the decomposition of organic pollutants could contribute to the wider use of vermicomposting to dispose of sewage sludge.
While vermicompost has many advantages, a number of obstacles need to be overcome before it can be routinely used in Hungary. Many landowners regard sewage sludge compost as hazardous waste that could contaminate their soil and crops rather than as a nutrient and soil amendment. Although numerous studies have been published on sewage sludge, the assessment of long-term effects, including the issues currently of most concern in Hungary, is still lacking.
Vermicomposting is therefore a promising, innovative technology for sewage sludge recycling. Sewage sludge and sewage sludge composts with pollutant contents greater than the limits laid down in Government Regulation 50/2001. (IV.3.) can be made suitable for agricultural use by vermicomposting.
The 1,200-m-deep Budaörs-1 borehole provided important data for our understanding of the stratigraphy and tectonic setting of the southern part of the Buda Hills. Although previous reports contained valid observations and interpretations, a number of open questions remained. The importance of this borehole and the unsolved problems motivated us to revisit the archived core. The new studies confirmed the existing stratigraphic assignment for the upper dolomite unit (Budaörs Dolomite Formation) as the dasycladalean alga flora proved its late Anisian to Ladinian age assignment. An andesite dike was intersected within the Budaörs Dolomite. U–Pb age determination performed on zircon crystals revealed a Carnian age (~233 Ma), and settled the long-lasting dispute on the age of this dike, proving the existence of a Carnian volcanic activity in this area after the deposition of the Budaörs Dolomite. Palynostratigraphic studies provided evidence for a late Carnian to early Norian age of the upper part of the lower unit (Mátyáshegy Formation). This result verified an earlier assumption and reinforced the significance of the tectonic contact between the upper unit (Budaörs Formation) and the lower unit (Mátyáshegy Formation). Based on structural observations and construction of cross sections, two alternative models are presented for the structural style and kinematics of the contact zone between the Budaörs and Mátyáshegy Formations. Model A suggests a Cretaceous age for the juxtaposition, along an E–W striking sinistral transpressional fault. In contrast, model B postulates dextral transpression and an Eocene age for the deformation. The latter one is better supported by the scattered dip data; however, both scenarios are considered in this paper as possible models.
The Late Cretaceous (Santonian) fish fauna of the Iharkút vertebrate site (Bakony Mountains, Hungary) is described here. The ichthyofauna includes the lepisosteid Atractosteus sp., the pycnodontid cf. Coelodus sp., Vidalamiinae indet., a non-vidalamiin Amiidae indet., Elopiformes indet., two indeterminate ellimmichthyiforms, cf. Salmoniformes indet., Acanthomorpha indet., at least one indeterminate teleostean, and numerous indeterminate actinopterygians (represented by teeth). Among these taxa, the Iharkút remains of Vidalamiinae and the suggested indeterminate Salmoniformes represent their first occurrence in the Late Cretaceous of Europe. The unidentifiable specimens may suggest the presence of further fish taxa. The gar remains described here further support the Atractosteus sp. affinity of the Iharkút form. Most of the Iharkút fishes are carnivorous, but durophagous taxa are also represented. Although chondrichthyan remains have not been identified in the Iharkút vertebrate material up to now, the ecological distribution of some local fish taxa presumes the possible vicinity of a marine–deltaic environment. Several Iharkút fish taxa are known from North American localities as well, suggesting that the Late Cretaceous European continental fish might have been more diverse and similar to that of North America than previously thought. The necessity of more intensive screen-washing at other European Late Cretaceous vertebrate sites is also emphasized.
In this study, new microthermometric data of fluid inclusions distributed along planar assemblages crosscutting a metamorphic quartz lens from the Mecsekalja Zone metamorphic complex are presented. Three fluid generations are defined, none of which have previously been identified by earlier paleofluid evaluations of the study area. Petrographic description of the host quartz is provided to identify textures related to crystalloplastic deformation resulting from ductile deformation. The textural relationship of the studied assemblages to the dynamic recrystallization features is discussed. The possible affinities of the fluids introduced in this study to those identified in the region by previous authors are discussed. The affinities and timing of the fluid flow events are discussed based on the physicochemical properties of the fluids. One local carbonic (high XCO2) fluid is recognized. A high- and a moderate-salinity fluid generation are also revealed. The relationship of these fluid generations to those defined in earlier studies from the Mórágy Granite and the Baksa metamorphic complex contributes new knowledge to the recognition of the regional paleofluid evolution.
Shock-driven annealing of pyroxene and shock deformation of olivine were analyzed in a recently found H chondrite called Csátalja. The most characteristic infrared (IR) spectral shape of shock-annealed sub-grained pyroxene was identified: the strongest peak occurs at 860 cm−1 with a smaller shoulder at 837−840 cm−1, and small bands are at 686, 635−638, and 1,044−1,050 cm−1. The appearance of forbidden bands in pyroxene and shift of band positions to a lower wave number in olivines clearly demonstrate the crystal lattice disordering due to shock metamorphism. The shock annealing produced mixed dark melt along fractures, which consists of feldspar−pyroxene and olivine−pyroxene melt. The dark shock melt at sub-grain boundaries of shocked pyroxenes and along fracture of pyroxenes is characterized by elevated Ca, Na, and Al content relative to its environment, detected by element mapping. So far, shock deformation of pyroxene and olivine was not studied by IR spectroscopy; this method has turned out to be a powerful tool in identifying the mixed composition of shock melt minerals. Further study of shock annealing of minerals, together with the context of shock melting at sub-grain boundaries, will provide a better understanding of the formation of high P–T minerals.
Finding the optimal number of realizations to represent the model uncertainty when applying stochastic approaches is still a relevant question in geostatistics. The essence of the method is to visualize the realizations in a suitably constructed attribute space. To construct this space, the static connectivity metrics of the realizations were used. Within this framework, the creation of new realizations can be regarded as a sampling process, in which each new stochastic image is the equivalent of a new sampling point in the attribute space. The sampling process begins with the first few realizations appearing in a dispersed manner in random parts of the attribute space. The addition of more realizations causes the gradual emergence of higher point densities, which in the end, results in a point structure where most of the points are located in areas of high point densities with areas of low point densities surrounding them. High point densities represent typical realizations showing very similar connectivity characteristics, whereas low point densities correspond to atypical realizations with stronger deviations from the bulk. In this sense, reaching the optimal number of realizations is the equivalent of reaching a state in the sampling process where high- and low point densities are present at the same time, yet high point densities do not dominate the overall structure of the attribute space, as they also reflect the redundancy of the information content. This desired structure is strongly analogous to the complete spatial randomness of spatial point processes, where the points are neither dispersed nor aggregated in space. Based on this analogy, the normalized version of Ripley’s K-function and the L-function for the spatial inhomogeneous Poisson point process was applied to find the optimal number of realizations. The method is illustrated on a computed tomography slice and on the real-life data of the Tisza-2 reservoir.
