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Earlier investigations at South Creek in northeastern Queensland established the importance of overland flow as a hydrologic pathway in this tropical rainforest environment. Since this pathway is ‘fast’, transmitting presumably ‘new’ water, its importance should be reflected in the stormflow chemistry of South Creek: the greater the volumentric contribution to the stormflow hydrograph, the more similarity between the chemical composition of streamwater and of overland flow is to be expected. Water samples were taken during two storm events in an ephemeral gully (gully A), an intermittent gully (gully B) and at the South Creek catchment outlet; additional spot checks were made in several poorly defined rills. The chemical composition of ‘old’ water was determined from 45 baseflow samples collected throughout February. The two events differed considerably in their magnitudes, intensities and antecedent moisture conditions. In both events, the stormflow chemistry in South Creek was characterized by a sharp decrease in Ca, Mg, Na, Si, Cl, EC, ANC, alkalinity and total inorganic carbon. pH remained nearly constant with discharge, whereas K increased sharply, as did sulfate in an ill-defined manner. In event 1, this South Creek stormflow pattern was closely matched by the pattern in gully A, implying a dominant contribution of ‘new’ water. This match was confirmed by the spot samples from rills. Gully B behaved like South Creek itself, but with a dampened ‘new’ water signal, indicating less overland flow generation in its subcatchment. In event 2, which occurred five days later, the initial ‘new’ water signal in gully A was rapidly overwhelmed by a different signal which is attributed to rapid drainage from a perched water table. This study shows that stormflow in this rainforest catchment consists predominantly of ‘new’ water which reaches the stream channel via ‘fast’ pathways. Where the ephemeral gullies delivering overland flow are incised deeply enough to intersect a perched water table, a delayed, ‘old’ water-like signal may be transmitted.
Fast analysis of different species of molecules in soils is investigated by capillary electrophoresis (CE). Several CE techniques for the analysis of inorganic ions and carbohydrates have been tested. With regard to the intents of pedologists and the usually large number of soil analyses a bundle of CE systems is proposed, capable of effecting time-saving soil analyses. Adapted electrolyte systems recently published and new separation systems are described. Examples of the application of these methods to two different soil samples are presented.
Inhalt: Polnische Staatsverschuldung vor 1990 - Auslandsverschuldung - Inlandsverschuldung Die Entwicklung der Staatsverschuldung in der Transformationsphase - Entwicklung der Auslandsverschuldung in den Jahren 1990 - 1994 - Entwicklung der Inlandsverschuldung in den Jahren 1990 - 1994 Szenarien für die Entwicklung des Schuldendienstes - Die Gesamtverschuldungsprognose in Inlandswährung - Szenarien für die Staatseinnahmenentwicklung - Gegenüberstellung der Staatseinnahmen und des Gesamtschuldendienstes - Entwicklung des Auslandsschuldendienstes in Auslandswährung Zur Realitätsnähe der Szenarien
Chemical fingerprints of hydrological compartments and flow paths at La Cuenca, western Amazonia
(1995)
A forested first-order catchment in western Amazonia was monitored for 2 years to determine the chemical fingerprints of precipitation, throughfall, overland flow, pipe flow, soil water, groundwater, and streamflow. We used five tracers (hydrogen, calcium, magnesium, potassium, and silica) to distinguish “fast” flow paths mainly influenced by the biological subsystem from “slow” flow paths in the geochemical subsystem. The former comprise throughfall, overland flow, and pipe flow and are characterized by a high potassium/silica ratio; the latter are represented by soil water and groundwater, which have a low potassium/silica ratio. Soil water and groundwater differ with respect to calcium and magnesium. The groundwater-controlled streamflow chemistry is strongly modified by contributions from fast flow paths during precipitation events. The high potassium/silica ratio of these flow paths suggests that the storm flow response at La Cuenca is dominated by event water.
Previous hydrometric studies demonstrated the prevalence of overland flow as a hydrological pathway in the tropical rain forest catchment of South Creek, northeast Queensland. The purpose of this study was to consider this information in a mixing analysis with the aim of identifying sources of, and of estimating their contribution to, storm flow during two events in February 1993. K and acid-neutralizing capacity (ANC) were used as tracers because they provided the best separation of the potential sources, saturation overland flow, soil water from depths of 0.3, 0.6, and 1.2 m, and hillslope groundwater in a two-dimensional mixing plot. It was necessary to distinguish between saturation overland flow, generated at the soil surface and following unchanneled pathways, and overland flow in incised pathways. This latter type of overland flow was a mixture of saturation overland flow (event water) with high concentrations of K and a low ANC, soil water (preevent water) with low concentrations of K and a low ANC, and groundwater (preevent water) with low concentrations of K and a high ANC. The same sources explained the streamwater chemistry during the two events with strongly differing rainfall and antecedent moisture conditions. The contribution of saturation overland flow dominated the storm flow during the first, high-intensity, 178-mm event, while the contribution of soil water reached 50% during peak flow of the second, low-intensity, 44-mm event 5 days later. This latter result is remarkably similar to soil water contributions to storm flow in mountainous forested catchments of the southeastern United States. In terms of event and preevent water the storm flow hydrograph of the high-intensity event is dominated by event water and that of the low-intensity event by preevent water. This study highlights the problems of applying mixing analyses to overland flow-dominated catchments and soil environments with a poorly developed vertical chemical zonation and emphasizes the need for independent hydrometric information for a complete characterization of watershed hydrology and chemistry.
Based on the discussion on Germany´s new 'central location', the author tries to sketch Germany´s geopolitical position in view of the constellation of powers in Europe from a national point of view. This favourable position offers a great chance for the country to play an active role in Europe’s integration. However, German historical heritage as well as the delicate relationship of Germany´s political elite to the use of power are reasons for the country´s hesitation to fulfill her neighbours’ and her allies’ expectations. Anyhow, Summaries 192 rooted in the West-European and transatlantic integration is Germany the natural dooropener for its Eastern, South-Eastern and Baltic neighbours to become 'members of the club'. )</a> Jahresabo: 40,00 € (ermäßigt: 25,00 €)
The Chinese coastal cities play an increasing economic role in the Yellow Sea region. The inclusion of these cities into the intra Asian economic cooperation is accomplished not only in the conventional sphere of trade but also by a growing involvement in telecommunication networks, technological exchange and the circulation of human resources. That is why these cities emerge as autonomous actors in the East Asian integration process. In this context national states face deep structural change, especially in the field of sovereignty and territory. Concerning the internal situation of China, this change could also cause a turn over of the relationship between the central government and the regions.
The article argues that the concept of statehood is not functioning any longer. It exists a crisis for the international legal order which is represented by the failure of state to maintain order within its borders. The problem of violence in international relations are connected to the implosion of a considerable number of the state entities in the contemporary international society. The federalist institutional approach in international law and international theory could not contribute in an appropriate way to the solution of the "problem of violence", because it supposes a willingness on the part of states to do so. Only the concept of "national interest", in a sociological sense, connected to the development of a discource of solidarity and mutual responsibility between the "West" and the "rest of the world" offers the possibility to create a common consciousness which could make it easier to overcome the contemporary crises for the international legal order.
The failure of politics is closely connected with deeply rooted misconceptions about the term politics. The author argues that a re-reading of Immanuel Kant's work "The Perpetual Peace" written 200 years ago offers a challenging possibility for a new conceptualization of politics, morality and peace. Morality is seen by Kant as an essential dimension of politics and the implementation and acknowledgement of laws by moral demands is defined as a precondition for a community of free citizens. In its public discourse politics does require law and morality. Deriving future rights from existing laws is one of the most favored argumentation used by politicians in the public. If the needs of law and justice are interpretated by politicians in their own interest, i.e. above all guarantees for the realization of political selfdetermination, then a real chance will exist for improving peace in the future.
The Voyager 2 Photopolarimeter experiment has yielded the highest resolved data of Saturn's rings, exhibiting a wide variety of features. The B-ring region between 105000 km and 110000 km distance from Saturn has been investigated. It has a high matter density and contains no significance features visible by eye. Analysis with statistical methods has let us to the detection of two significant events. These features are correlated with the inner 3:2 resonances of the F-ring shepherd satellites Pandora and Prometheus, and may be evidence of large ring paricles caught in the corotation resonances.