Fundamentals of geology I. (lithosphere) 1 1. The formation of the Earth 1


Fig. 12.13. River network of Hungary (www.enfo.agt.bme.hu)



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Fig. 12.13. River network of Hungary (www.enfo.agt.bme.hu)

12.1.2. 12.1.4. Soils

Soils are amongst the most important natural resources of Hungary. The favourable landscape, climate and soil conditions allowed the original Hungarians to settle in the Carpathian Basin. When looking at the soil map of Hungary, the various colours reflect how differences in environmental factors have determined the development of the soil cover.

In mountainous areas, higher precipitation and lower temperatures lead to the development of soils under forest vegetation. These fertile soils, known as uvisols, were heavily influenced by percolating water which led to the accumulation of clay in the subsoil. In the area between the mountains and the Hungarian Great Plain, young soils without distinct profile development are found (Cambisols). In lowland areas, one can find dark Chernozems, the most fertile soil of Hungary that supports the country’s agricultural production. Soils in river valleys that have developed on stratified sediments are called Fluvisols. Arenosols, soils that have developed on windblown sands deposited after the end of the last ice age, are extensive in certain parts of the country. In certain situations, ground water containing soluble salts can be found close to the surface. If evaporation is higher than precipitation, then saltaffected soils such as Solonchaks and Solonetzs can be found.



The soils of Hungary have been used very intensively throughout history for the cultivation of crops, for animal grazing and supporting woodlands for construction material. Currently, 48% of land is used for crops (mostly wheat and corn), 21% are forests, 8% are grasslands and 20% is uncultivated. The major limitation to agriculture in Hungary is precipitation. Climate change models predict that Hungary will experience extreme precipitation events in the future. The greatest challenge is to store the rainfall within the soil through effective soil management practices. Such techniques will control erosion, minimise the loss of topsoil and maintain or even enhance organic carbon and the bio-diversity levels of the soils (Fig. 12.14.).



Fig. 12.14. Genetic soil types of Hungary (www.enfo.agt.bme.hu)

12.2. 12.2. Environmental geological features of Hungarian main areas

Hungary has three major geographic regions (which are subdivided to seven smaller ones): the Great Hungarian Plain, lying east of the Danube River; the Transdanubia, a hilly region lying west of the Danube and extending to the Austrian foothills of the Alps; and the North Hungarian Mountains, which is a mountainous and hilly country beyond the northern boundary of the Great Hungarian Plain. But we can determine six main regions on the base of geographycal properties (Fig. 12.1.).

12.2.1. 12.2.1. Great Hungarian Plate

Great Hungarian Plain, a flat, fertile lowland, southeastern Hungary, also extending into eastern Croatia, northern Serbia, and western Romania. Its area is 40,000 square miles (100,000 square km), about half in Hungary. In its natural state the Great Alfold is a steppeland broken up with floodplain groves and swamps—a southwestern projection of the Russian steppes. In Hungary flood control, irrigation, and swamp drainage projects have added large areas of cultivable land. Cereals, fodder crops, livestock, vegetables, and fruit are widely raised. The original arid grasslands or steppe (Hungarian puszta) survive in the Hortobágy area east of Budapest. To the north and east of the plains lie the foothills of the Carpathian arc, to the south and west the Balkan Mountains. The plains are generally divided into two areas: the region between the Danube River and its tributary, the Tisza, and the region east of the Tisza (the Tiszántúl). The former is mostly windblown sandy soil with loess in places and extends across the now-regulated Danube floodplain to the west and across the Tisza floodplain in the east. The Tisza River, before it was regulated, flooded large parts of the plain. The area east of the Tisza has alluvial deposits, loess, and windblown sand. In the geomorphologic history of the Great Alfold, a range of block-faulted mountains, coincident with the present plain, submerged into an inland sea (known as the Pannonian Sea) in the Pliocene Epoch (i.e., about 5.3 to 2.6 million years ago). This was followed by uplift on the margins, leaving the Great Alfold area as an inland lake, which dried up or was filled with riverine deposits from the surrounding uplifted highlands. The present drainage pattern derives from the postglacial river pattern.

12.2.2. 12.2.2. Little Hungarian Plate

Little Hungarian Plain, extensive basin occupying the northwestern part of Transdanubia in northwestern Hungary, and extending into Austria and Slovakia (where it is called Podunajská Lowland). It has an area of approximately 3,000 square miles (8,000 square km). It is bounded on the south and east by the highlands of Transdanubia (Bakony and Vértes), to the west by the foothills of the Austrian Alps, and to the north by the Carpathians in Slovakia. The major drainage direction is west-east via the Danube River. The Rába River and its tributaries drain the Hungarian section through Győr, and in Slovakia the Váh River system enters the Danube at Komárno (Komárom).

Some of the Little Alfold is exceptionally rich agricultural land that produces wheat, corn (maize), rye, barley, sugar beets, potatoes, fodder crops, table vegetables, and tobacco; the basin has orchards and vineyards. Livestock breeding—dairy cattle, pigs, horses, and poultry—is also important. The climate is relatively dry, but abundant water comes from the surrounding highlands. Only in its middle and north-central parts is the Little Alfold properly a plain; on the margins are degraded alluvial fans and low hills. The major settlement in the area is Győr. Submergence and basin formation of the Little Alfold began several million years ago. Deposition and local submergence has continued on a smaller scale, and the Little Alfold is subsiding very slightly.

12.2.3. 12.2.3. Feet of the Alps

Feet of the Alps (=Alpokalja) is one of the hungarian geographic regions in Western Hungary. Its highest point in Hungary is Írott-kő, with 882 metres. Although there are several lower mountains, the majority of the territory is hilly. Fir forests are characteristic to the region. Alpokalja contains two major, but not very extensive mountain range: the Kőszeg Mountains and the Sopron Mountains. The Vas Hills and Balfi Hills are also considered part of the territory.

12.2.4. 12.2.4. Transdanubian Hills

The Transdanubian Hillslie in a east-west direction from Zala Valley to the Danube. Its borders are drawn by the Balaton in the north and Dráva Valley in the south. Two block mountains rise above the hilly region, like two islands; the Mecsek and Villányi mountains. The natural resources of the hills are mostly utilised as pastureland and those in the mountains are used in mining ore, coal and stone, and in tourism in caves and mineral spas.



12.2.5. Transdanubian Mountain Ranges

The Transdanubian Mountains are a mountain range in Hungary covering about 7000 km². Its highest peak is the Pilis, with a height of 757 metres. The Transdanubian Mountainslying from the north-western edge of the Balaton to the line of the Danube is the only region in Hungary which is situated only in the territory of Hungary. In the karst regions of the about 200 kilometer long mountains of south-west and north-east situation, a network system of groundwater has been formed. Karst water plays an essential role in the water sypply of the region. Some of the mountains (Bakony, Vértes) are famous for brown coal and bauxite mining. Several caves and 123 medical waters and thermal springs have given the Buda Hills a unique and natural value. The hills have special configuration, which provides protection for its relief, woods, mineral sources and stones.

12.2.5. 12.2.6. North Hungarian Mountain Ranges

The North Hungarian Mountainsis the northern, mountainous part of Hungary. It is a separate geomorphological area within the Western Carpathians. The mountains run along in Northeast Hungary, and along the eastern parts of the Hungarian-Slovak border in a broad band from the Danube Bend to the town of Prešov.

The North Hungarian Mountains begin with the mountain range of Börzsöny, adjacent to the Danube Bend, where it meets the Transdanubian Mountains. The Börzsöny range is about 600 km² in area, and mainly of volcanic origin. The highest peak is the Csóványos (938 m). The next range towards the east is the Cserhát, with the same geological composition as the Börzsöny. Erosion here was more severe: these are mere hills and comprise the lowest part of the North Hungarian Mountains. The highest point is the Naszály (654 m). Kékes, the country's highest peak at 1014 metres, is located in the next range, Mátra. However, the range's average height is only 600 metres, less than that of the neighbouring Bükk. Mátra is also of volcanic origin. The Bükk is a limestone range; it has the highest average height in Hungary. It is rich in caves, some of which were inhabited in ancient times. The Aggtelek Karst area is a geologic formation spanning the Hungarian-Slovakian border, and the reason for the Caves of Aggtelek Karst and Slovak Karst World Heritage Site, and the Hungarian Aggtelek National Park. Hungary's most popular cave, the Baradla, is located there. The Zemplén Mountains are again of volcanic origin; the soil's high quality favours viticulture.

12.3. 12.3. Environmental problems of Hungary

12.3.1. 12.3.1. Natural hazards

Natural hazards are quiet rare in Hungary. The Carpathian Basin is a stabile terrain so volcanism or earthquakes are not significant. The most often disasters are floods in this region. Floods are very fast and intensive until the river trainings. Alluviums are under agricultural crop today and many people living there. Because of this, these are the most imperilled areas in Hungary.

12.3.2. 12.3.2. Anthropogenous environmental hazards

Contribution to the solution of the problem of formulating criteria for the identification and analysis of the hazards of man-made impact. It’s very difficult to identifying the hazards of anthropogenic impacts on organisms, including the hazards of man-made chemicals, have been formulated. This made it difficult to effectively combat many negative consequences of the human impact on the biosphere, and to assess in full the hazards of man-made chemicals (pollutants, xenobiotics). A new concept to identify potential dangers of anthropogenic impacts on the biosphere and organisms was formulated in some recent publications. The new approach allows identifying and analyzing the negative man-made effects and the entire impact on organisms and the biosphere in a more objective way and more fully than was it was done previously. The proposed method allows better organizing information on biological effects associated with exposure to chemical substances, as well as the data on other anthropogenic influences on the organisms and the biosphere.

In the next subchapters, we will review Hungary’s environmental states.

 

 



12.3.2.1. 12.3.2.1. Air pollution in Hungary

The air quality in Hungary generally corresponds to the EU average, though there are Hungarian settlements where air quality is still not on the 'good' level, with significant differences between rural parts and larger cities. Concentrations of SO2, CO, benzene and lead are below set limits throughout the country. Decreased emissions of sulphur dioxide over the past one to two decades resulted in a lower ambient air concentration of that pollutant.



Levels of nitrogen oxides and ground-level ozone are (relatively) high, with the latter showing an increasing trend similar to other parts of Europe. Nitrous oxides play a significant role in acidification and eutrophication of ecosystems, while ground-level ozone poses a serious threat to agricultural production. Levels of particulate matter and NOx in ambient air occasionally exceed the health limit values near main traffic routes in larger cities (Fig. 12.15.).




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