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Central Hungary (central + hungary)
Selected AbstractsEstimation of net nitrogen flux between the atmosphere and a semi-natural grassland ecosystem in HungaryEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 5 2010A. Machon The aim of this work is to estimate the net N balance (deposition , emission) between the atmosphere and a semi-arid, semi-natural grassland (Bugac station, Central Hungary, CarboEurope IP, NitroEurope IP level 3 site). Dry deposition of N compounds has been determined by the inferential method, based on continuous monitoring of NO2 gas and daily 24-hour concentration measurements of HNO3 vapour, NH3 gas, and NH4+ and NO3, particles, using dry deposition velocities from the literature, measured above surfaces with the same characteristics as Bugac station. The bi-directional flux of NH3 within the atmosphere and the canopy (excluding soil emission) has also been estimated by the inferential method. Wet deposition of nitrate and ammonium ions was calculated on the basis of daily precipitation sampling and concentration measurements of nitrate and ammonium ions. To estimate the soil-atmosphere exchange of different gaseous N forms (N2, NO, N2O, NH3), the DNDC model was used as validated by the chamber measurements of NO and N2O soil emission fluxes. Soil emissions of NO and N2O have been determined by dynamic and static soil chamber methods, respectively. The measurement and modelling activity covers a complete year. Using the measured and modelled data, the calculated N balance at Bugac station between August 2006 and July 2007 is estimated at ,8.8 kg N ha,1 year,1 (deposition) as a sum of the deposition and emission terms (,10.4 and 1.6 kg N ha,1 year,1, respectively). Due to the warm and dry weather during the examined period, wet fluxes were substantially lower than usual, which may also have altered the regular yearly course of dry deposition and emission. [source] Rudabánya: A late miocene subtropical swamp deposit with evidence of the origin of the African apes and humansEVOLUTIONARY ANTHROPOLOGY, Issue 2 2002László Kordos Abstract Rudabánya, a rich late Miocene fossil site in northern central Hungary, has yielded an abundant record of fossil primates, including the primitive catarrhine Anapithecus and the early great ape Dryopithecus. While the affinities of Anapithecus are not clear, Dryopithecus is clearly a great ape sharing numerous characteristics of its dental, cranial and postcranial anatomy with living great apes. Like all Miocene hominids (great apes and humans), Dryopithecus is more primitive in a number of ways than any living hominid, which is probably related to the passage of time since the divergence of the various lineages of living hominids, allowing for similar refinements in morphology and adaptation to take place independently. On the other hand, Dryopithecus (and Ouranopithecus) share derived characters with hominines (African apes and humans), and Sivapithecus (and Ankarapithecus) share derived characters with orangutans, thus dating the split between pongines and hominines to a time before the evolution of these fossil great apes. Pongines and hominines follow similar fates in the late Miocene, the pongines moving south into Southeast Asia from southern or eastern Asia and the hominines moving south into East Africa from the Mediterranean region, between 6 to 9 Ma. [source] Responses of great reed warblers Acrocephalus arundinaceus to experimental brood parasitism: the effects of a cuckoo Cuculus canorus dummy and egg mimicryJOURNAL OF AVIAN BIOLOGY, Issue 4 2002István Bártol Egg rejection behaviour towards parasitic eggs was studied in a great reed warbler Acrocephalus arundinaceus population in central Hungary, which was heavily (about 65%) parasitised by the common cuckoo Cuculus canorus. Clutches were experimentally parasitised during the egg-laying period with artificial, moderately mimetic cuckoo eggs or with conspecific eggs that were good mimics of the hosts' eggs. Great reed warblers rejected 76.2% of the artificial cuckoo eggs, mainly by ejection, but accepted most of the conspecific eggs (87.5%). Cuckoo eggs in naturally parasitised clutches were rejected at a lower rate (32%). When, in addition to the egg mimicry experiments, a stuffed cuckoo was placed near the nest, accompanied by the recording of a female cuckoo call, hosts' rejection rate of the artificial cuckoo egg increased from 76% to 96%. The sight of the cuckoo, on the other hand, did not influence host's rejection behaviour when a conspecific egg was used in the experiment. A stuffed collared dove Streptopelia decaocto, accompanied by its call, was used as a control, and did not cause any increased rejection. Great reed warblers were more aggressive towards the cuckoo than to the dove dummy. When the cuckoo eggs in naturally parasitised clutches were exchanged with artificial cuckoo eggs, we observed no increase in the rejection rate. We conclude that great reed warblers in our heavily parasitised population are capable of detecting brood parasitism in their clutch by identifying the parasitic egg. The efficiency of this identification depends mainly on the mimicry of the foreign egg. The sight of the cuckoo at the nest may increase rejection rate by stimulus summation, and this conditional effect is mainly affected by the degree of mimicry of the parasitic egg. [source] Habitat heterogeneity overrides the species,area relationshipJOURNAL OF BIOGEOGRAPHY, Issue 4 2008András Báldi Abstract Aim, The most obvious, although not exclusive, explanation for the increase of species richness with increasing sample area (the species,area relationship) is that species richness is ultimately linked to area-based increases in habitat heterogeneity. The aim of this paper is to examine the relative importance of area and habitat heterogeneity in determining species richness in nature reserves. Specifically, the work tests the hypothesis that species,area relationships are not positive if habitat heterogeneity does not increase with area. Location, Sixteen nature reserves (area range 89,11,030 ha) in central Hungary. Methods, Four-year faunistic inventories were conducted in the reserves involving c. 70 fieldworkers and 65 taxonomists. CORINE 50,000 land-cover maps were used for calculating the heterogeneity of the reserve landscape (number of habitat types, number of habitat patches and total length of edges). Results, Large reserves were less heterogeneous than small reserves, probably because large reserves were established in large blocks of unproductive land whereas small reserves tended to be in more fertile land. In total, 3975 arthropod species were included in the analysis. The slope of the species,area relationship was positive only for Neuroptera and Trichoptera. There was no significant relationship in the other nine taxa examined (Collembola, Acari, Orthoptera, Thysanoptera, Coleoptera, Araneae, Diplopoda, Chilopoda, Diptera). The density (number of species ha,1) of all species, however, showed a positive correlation with heterogeneity. Main conclusions, The general lack of fit of species,area relationships in this study is inconsistent with most previous published studies. Importantly, and unlike many other studies, habitat heterogeneity was not correlated with reserve area in the studied system. In the absence of this source of covariation, stronger relationships were identified that suggested a fundamental link between species richness and habitat heterogeneity. The results indicate that habitat heterogeneity rather than area per se is the most important predictor of species richness in the studied system. [source] | ||||||||||