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Inland excess water (IEW) is a form of surplus surface water, often regarded as a specific flood type. However, it occurs most frequently in local depressions of large flat areas, irrespective of river floods and the surface water networks. IEW is considered to be a typical Carpathian Basin problem, as it can cause major land degradation problems in the agricultural areas of Hungary, mainly located on the Great Hungarian Plain (GHP). An innovative method for mapping the probability of IEW inundation is proposed in this study. This method is based on the geostatistical modelling of the relationship between the natural and human driving factors and the occurrence of IEW inundations. The results show that significant part of the GHP (about 500,000 hectares) is moderately or highly affected by IEW inundations, where the combination of multiple influencing factors simultaneously occur. The resulted IEW inundation probability map can be used to meet future challenges in agricultural management and the adaptations to climate change effects. [ABSTRACT FROM AUTHOR]

Aim We used a combination of new and previously published palaeoecological data to test three hypotheses: (1) that wooded steppe persisted in the Great Hungarian Plain throughout the Holocene; (2) that wooded steppe and steppe were most extensive between c. 9900 and 8300 cal. yr bp (the ‘Boreal steppe’ period); and (3) that Southern Continental, Pontic and Eastern Sub-Mediterranean steppe species reached the region during the early Holocene via the ‘Lower Danube Corridor’. Location Sarló-hát oxbow lake, Hungary and the Eastern European wooded steppe zone. Methods Holocene sediments deposited in the Sarló-hát oxbow lake were subjected to pollen and microcharcoal analyses. Twelve radiocarbon age estimates were obtained to determine sediment chronology. In addition, previously published palaeoecological data from the Great Hungarian Plain were compiled, analysed and compared with previous studies in other regions of steppe and wooded steppe in eastern Europe. Results Palynological data from two sediment cores extending to c. 11,400 cal. yr bp indicate the persistent dominance of the landscape by temperate deciduous wooded steppe throughout the Holocene, although with varying canopy composition. Warm-continental steppe grasslands and saline tall-grass meadows developed on edaphically constrained areas, which remained steppe-dominated throughout the Holocene. The extent of steppe grasslands did not increase between 9900 and 8300 cal. yr bp. After c. 3100 cal. yr bp, anthropogenic activities led to the development of cultural steppe. Thermophilous steppe species of the Southern Continental, Pontic and Sub-Mediterranean floristic elements probably reached the Great Hungarian Plain principally via the Lower Danube Corridor during the late glacial interstadial and Holocene. Eurythermic members of these elements, however, probably survived the Last Glacial Maximum in favourable microsites, extending their ranges during the Holocene from these local sources. Main conclusions Our results confirm the Holocene persistence of wooded steppe in the Great Hungarian Plain, disprove the ‘Boreal steppe’ theory, and suggest an Early Holocene period of greater vegetation openness between 11,400 and 9900 cal. yrbp. Evidence for the post-glacial immigration of south-eastern steppe elements into the Carpathian Basin is equivocal: the last glacial/interglacial presence of several southern steppe species suggests that the Hungarian Plain hosted suitable habitats for them during warm and cold phases alike. [ABSTRACT FROM AUTHOR]

The spatial distribution of the annual mean urban heat island UHI intensity was simulated applying empirical models based on datasets from urban areas of Szeged and Debrecen, using simple and easily determinable urban surface cover variables. These two cities are situated on the Alföld Great Hungarian Plain and have similar topographic and climatic conditions. Temperature field measurements were carried out, Landsat satellite images were evaluated, and then one and multiple variable models were constructed using linear regression techniques. The selected multipleparameter models were verified using independent datasets from three urban settlements. In order to obtain some impression of the mean UHI patterns in other cities with no temperature measurements available, the better model was extended to urban areas of four other cities situated in geographical environments similar to Szeged and Debrecen. The main shortcoming of typical empirical models, namely that they are often restricted to a specific location, is overcome by the obtained model since it is not entirely site but more region specific, and valid in a large and densely populated area with several settlements. Copyright © 2009 Royal Meteorological Society [ABSTRACT FROM AUTHOR]