Electronic Library of Scientific Literature - © Academic Electronic Press


Volume 54 / No. 4 / 2002

Eltijani A. Elias,* Fayez Alaily**

Effects of long-term irrigation on soluble salts and exchangeable base cations in Vertisols from Sudan Gezira

 E. A. Elias, F. Alaily: Effects of long-term irrigation on soluble salts and exchangeable base cations in vertisols from Sudan Gezira. Geografický časopis, 54, 2002, 4, 5 figs., 3 tabs., 16 refs.

Salt concentrations as affected by long term irrigation and continuous cropping for more than 80 years in Gezira soil were assessed. The study included two profiles in the Gezira Research Station (GRS) farm at Wad Medani. One profile was in a plot that was left permanently fallow while the other one was in a plot under continuous cropping according to the rotation of the Gezira Scheme. Evidence was not found for any increase in salinization accompanying irrigation in these soils despite the arid climate and the primary saline phase associated with these soils. Investigations carried out in the study included total chemical composition, CEC, EC, exchangeable cations, soil pH and soluble cations and anions. Difference in base saturation found in these soils is explained in terms of changes in quantities of exchangeable bases as affected by leaching, dissolution and possibly redistribution of bases.

Key words: Vertisol, irrigation, salt affected soil, Gezira, Sudan

Szymon Szewrański, Józef Sasik, Romuald Żmuda*

The water erosion process against the background of outflow condition changes in upland catchment

S. Szewrański, J. Sasik, R. Żmuda: The water erosion process against the background of outflow condition changes in upland catchment. Geografický časopis, 54, 2002, 4, 2 tabs., 6 figs., 11 refs.

The investigations of denudation processes were carried out in the Mielnica Stream catchment area in the hydrological years 1977/78-1993/94. The object is situated in the Trzebnica Hills area, considered as one of the most eroded regions of Poland. Daily bathometrical measurements of suspended load and observations of hydrometeorological conditions were made. Investigations were extended by analysis of washed out chemical compounds in the years 1987/88-1989/90. The character of agricultural production has changed as a result of the economic transformation in Poland since 1990. The need for new ways of agriculture production in the catchment,led to fishponds being built in 1997. The outflow denudation investigations were restarted in 1998. In this article the amounts of carried out material are presented against the background of changes in the catchment area.

Keywords: water erosion, chemical denudation, agricultural catchment, sediment yield

Ján Pravda*

analytické a syntETICKÉ MAPY v Klasifikácii máp

J. Pravda: Analytical and synthesized maps in map classification. Geografický časopis, 54, 2002, 4, 6 figs., 22 refs.

There is no single classification of maps in cartography recognized in the whole world. Approaches and criteria of map classification considerably differ above all between the USA and Europe. The European classification of maps also includes analytical, comprehensive and synthesized maps. The class of comprehensive maps though, seems inadequate and questionable. Multicriterial and multilayer map classification is proposed which contains analytical (elemental), componential and synthesized maps.

Key words: maps, classification of maps in USA and in Europe, analytical map, synthesized map

Jozef Jakál*


J. Jakál: Karst landscape, its properties and resistance to anthropic impact. Geografický časopis, 54, 2002, 4, 2 figs., 1 tab., 21 refs.

The paper is focused on solution of problems which emerge in the karst landscape as consequences of its use by man. Relationships between the properties of natural elements in the karst geosystem with emphasis on interaction between characters of georelief and water are analysed. Resistance of karst landscape is evaluated by geomorphological criteria. Economic activities with negative impact on the karst geosystem, as well as on its natural potential are identified.

Key words: karst landscape, georelief, geomorphological criteria, natural potential

Ján Paulov*

Komplexita a geografia**

J. Paulov: Complexity and geography. Geografický časopis, 54, 2002, 4, 10 refs.


The basic objective of this paper, originally intended to be given at the plenary session of the 13th Congress of the Slovak Geographical Society, held in September 2002, is to bring an introductory overview on the complexity as highly relevant concept of contemporary science and its relation to geography. Complexity is a fundamental attribute of our world. However, this attribute/concept is strongly related to the attribute/concept of self-organisation. Therefore the idea of self-organisation, its roots in the Prigogine theory of dissipative structures themselves, is shortly discussed. To show the relevance of self-organisation for geography an example, taken from the paper by Allen (1982), is given, which demonstrates how the settlement system can evolve into hierarchical structure.

Key words: complexity, self-organisation, dissipative structures

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