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This investigation has been carried out at Badinska River watershed -one of the most famous torrents in Bulgaria. The purpose of the survey is to analyse the main erosion factors and erosion potential of territories, with a view to assess soil erosion risk and opportunity of high water formation from watershed. A methodical approach for determination and mapping of the territories in terms of the class of erosion risk with the use of GIS is applied. Assessments are made according to the "Methodology for preparing the national long term programme for protection against erosion and flooding in forestlands". The total assessment for Badinska river watershed is "low to moderate" potential risk and "very low to low" actual erosion risk. About of 5% of the forest stock territory is with "moderate" and "moderate to high" actual risk, and the biggest part of this territory (about 63%) is in the main stream watershed above the Yaloviko tributary.

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It is now widely acknowledged that Bulgarian academic discourses of the country’s so-called communist era (1945-1989) were heavily politicized with the aim of nationalizing and ethnicizing the history of the Bulgarian people. This communist era phenomenon subscribes to a chronologically vaster process of nationalist continuum recognized to have spanned from the middle-end of the nineteenth century to at least the early 1990s. Despite this trend, Bulgarian academics, especially in the field of archaeology, have more recently presented their post-communist, transition period disciplines as ideology-free, objective, scientific research. In this paper, we provide examples of recent theoretical developments and interpretations in the sub-field of thracology – studies of ancient Thracian culture – that indicate that this claim to objectivity is unfounded. Based on the examples provided we argue that not only have Bulgarian academic discourses in the fields in question not severed with the ethnicizing practices of the so-called nationalist continuum of the pre-communist and communist eras, but they are now flourishing on the nationalist foundation of the preceding century and a half. As such discourses are reproduced unquestioningly in specialized publications, their influence on right wing populism is incontestable as they provide the latter, wittingly or not, with the scientific authority it needs to justify its ethnicizing of “historical” tenets of racial and social discrimination.

auftreten, während sich in der Stahlbewehrung nur elastische Verformungen bilden, die von der äußeren Lasteinwirkung herrühren.Als Ergebnis dieser Verformungen und wegen der Tatsache, daß durch den Kleber auf Epoxid-Grundlage eine feste Verbindung zwischen Bewehrung und Holzmaterial des Trägers hergestellt wird, tritt in jedem Querschnitt, der ständiger Einwirkung des äußeren Moments M o unterliegt, in der Zeit t eine neue, zusätzliche, sich selbst im Gleichgewicht haltende Kräftegruppe auf: M h (t); M a (t) (Bild 2). Die Größe dieser Zur Bestimmung der Umlagerungsgrößen in Holz in der Zeit t wurde nach der Theorie des viskoelastischen Körpers für das Kriechen des Holzes eine Volterra-Integralgleichung der zweiten Art abgeleitet. Für die Lösung dieser Gleichungen wird eine analytische Methode vorgeschlagen, die Laplacesche Transformationen ausnützt. Die Anwendung wird an einem Beispiel gezeigt.Creep behaviour of steel reinforced timber beams. The paper presents analysis of the stress changes due to creep of the wooden members in simply supported timber beams with tension reinforcement. For determining the redistribution of stresses in beam section between wooden and tension reinforcement with respect to time t, a Volterra integral equation of the second kind have been derived on the basis of the theory of the viscoelastic body. An analytical method, which makes use of Laplace transformation for solving these equations, is proposed. The application of the method is explained with the aid of an example.

An overview of the activities overtaken during risk of flooding situations, in one of the more often flooding region - the watershed of Varbitsa river (Southeastern part of Bulgaria) - has been performed. The main cognitive parameters for risk perception and risk definition, depending on regional, social and historical factors have been examined. The existing information and instructions for mass media communication in relation to the process of interaction in a disaster situation have been discussed. In connection to determination of the risky segments in the basin and plans for announcement, the prevention communication measures have been outlined. On the basis of the Bulgarian normative legislation, the activities concerning organization of communications in a risk-of-disaster situation and mutual aid between authorities, which are part of the Integrated Help System have been indicated. It has been accented on the necessity of a more effective realization of the action plans during natural disasters and especially flooding, in order to improve the partnership between authorities and participants in the communication process during risk-of-flooding situations

Fly ash zeolites (FAZ) are promising materials for adsorbents, ion-exchangers and catalysts. FAZ usually possess a mixed micro-mesoporous structure that facilitates mass transport phenomena through their framework. Due to the transfer of iron spinel oxides and many metal species from the raw material, their catalytic and adsorption ability can be improved further by modifying them with metal oxide nanoparticles. In the present study, copper- (Cu-FAZ) and cobalt-modified (Co-FAZ) FAZ were prepared by incipient wetness impregnation technique, the loading of 6 wt. % copper or cobalt in the zeolite framework was achieved. Cu-FAZ and Co-FAZ were investigated by X-ray diffraction to clarify the state of Cu and Co into the FAZ matrix, while surface studies by nitrogen adsorption/desorption technique were carried out to trace the effect of modification on the FAZ surface characteristics. Modified and parent FAZ were investigated as adsorbents and catalyst for decontamination of water and gases from organic pollutants. The simultaneous presence of Fe2+/Fe3+ and Cu2+/Fe3+ or Co2+/Fe3+ species in the modified FAZ stipulates easier oxygen release essential for organic degradation. The favorable combination of morphological and compositional peculiarities of modified FAZ contributes to their effective organic removal performance. Acknowledgements This work was financially supported by the National Science Funds, Ministry of Education and Science of Bulgaria under contract DN 17/18 and under Grant DNTS Slovak Republic 01/6.