Industrialization of Slovenia

A new European state, the Republic of Slovenia, was constituted in 1991. It used to be considered the most industrialized and economically developed federal unit of the former Yugoslavia. There were (in 1990) 362,732 workers employed in manufactur industry, which meant 46% of all employees in Slovenia. The industrialization occurred in two waves: the first one before the Great War, and the second one, imposed and conducted by the communist regime, in the 1960's and 1970's. The latter promoted the establishing of factories all over Slovenia, particularly in the less developed regions. This process was prolonged, and the result of universal industrialization of Slovenia was that 464 Slovenian settlements had one or more industrial plants. The willful industrialization caused the substantial transformation of society, and left its traces in geographic features of Slovenia as well. The intended incorporation of Slovenia into the international market will cause considerable dilemmas and a crisis in this type of industrialization.     

WSO-UV progress and expectations

The World Space Observatory Ultraviolet (WSO-UV) is the space mission that will grant access to the ultraviolet (UV) range in the post Hubble epoch. WSO-UV is equipped with instrumentation for imaging and spectroscopy and it is fully devoted to UV astronomy. In this article, we outline the WSO-UV mission model and present the current status of the project.     

The spectra of some discrete radio sources in 10–5000 MHz frequency range

On the basis of the absolute measurements in the 12.6–25 MHz frequency range and the relative measurements at frequencies 750, 1400, 2695 and 5000 MHz (NRAO) and 408, 1410 and 2650 MHz (Parkes), 57 standard spectra were obtained which are linear (on a log-log scale) in the range 12.6–5000 MHz. The comparison of the flux densities presented in the surveys at 10.03, 22.25, 26.3, 38, 86 and 178 MHz and the standard spectra was carried out and thus the correction coefficient was calculated. It was shown that the scale of absolute fluxes CKL on the frequencies 38 and 178 MHz is lowered on 28% and 8% respectively. The possible sources of divergences of the results of measurements in decametric wavelength is discussed. Making use of the corrected data at 38 MHz and 178 MHz, of the results at higher frequencies mentioned above and of the original results of measurements in the 12.6–25 MHz range, the spectra of 55 discrete sources were constructed. The spectra of 149 sources are also obtained on the basis of the surveys at 10.03, 22.25, 26.3, 38 and 178 MHz corrected according to standard spectra.     

Sergej Zilitinkevich (13.4.1936–15.2.2021)

Boundary-Layer Meteorology -     

Deep Geoelectrical Structure of the Central and Western Ukraine

The results of deep induction sounding in Ukraine made in the twenty-first century with the participation of the author have been summarized, including also a number of data obtained in the previous decades. The apparent resistivity and magnetic transfer function on the territories of western Ukraine and eastern Poland have been analyzed. The articulation of these data with the regional magnetic variation soundings allowed taking into account the influence of a static shift of areal interpretation of magnetotelluric resistivity results, which increased the reliability of interpretation. The analysis of induction sounding performed with 1D, 2D, and 3D inversions of magnetic transfer functions allowed localizing the crustal anomalies. The results are discussed.     

Late quaternary tephra layers along the Cilento coastline (southern Italy)

The results of stratigraphic and tephrostratigraphic analyses of several pyroclastic levels, collected along the coastal sector of the Cilento region (southern Italy), are presented. Some of these levels are here described for the fist time, others, already known in literature, were reconsidered in order to better understand their stratigraphic position and to point out the possible volcanic sources.     

Bacteriohopanepolyol biomarker composition of organic matter exported to the Arctic Ocean by seven of the major Arctic rivers

Bacteriohopanepolyols (BHPs) are a diverse group of membrane lipids produced by a wide variety of bacteria and can be used as molecular biomarkers for bacterial processes and populations in both modern and ancient environments. A group of BHPs, including adenosylhopane and structurally related compounds, have been identified as being specific to soils, enabling the transport of terrestrial organic matter (terrOM) to the marine realm to be monitored. Estuary surface sediment samples were obtained from the five Great Russian Arctic Rivers (GRARs; Ob, Yenisey, Lena, Indigirka and Kolyma) and river sediments were obtained from two North American Rivers (Yukon and Mackenzie). Analysis of the BHP signatures, using high performance liquid chromatography–tandem mass spectrometry (HPLC–MSⁿ), indicated the presence of 15 different BHPs originating from a variety of different bacteria, as well as a significant presence of terrestrially derived OM. Total BHP abundance and the contribution of the “soil-marker” BHPs to the total BHP pool increased eastwards among the GRAR sediments. This suggests increasing terrestrial OM or increased preservation of OM as a result of shorter periods of permafrost thawing. The North American rivers showed greatly differing BHP levels between the Yukon and Mackenzie rivers, with a greater BHP input and thus a relatively higher soil OM contribution from the Yukon. The Indigirka River basin in the eastern Siberian Arctic appeared to be the epicentre in the pan-Arctic BHP distribution trend, with the highest “soil-marker” BHPs but the lowest tetrafunctionalised BHPs. Aminobacteriohopanepentol, an indicator of aerobic methane oxidation, was observed in all the sediments, with the source being either the marine environment or methane producing terrestrial environments.     

Modelling of thermochemical plumes and implications for the origin of the Siberian traps

Thermochemical plumes form at the base of the lower mantle as a consequence of heat flow from the outer core and the presence of local chemical doping that decreases the melting temperature. Theoretical and experimental modelling of thermochemical plumes show that the diameter of a plume conduit remains practically constant during plume ascent. However, when the top of a plume reaches a refractory layer, whose melting temperature is higher than the melt temperature in the plume conduit, a mushroom-shaped plume head develops. Main parameters (melt viscosity, ascent time, ascent velocity, temperature differences in the plume conduit, and thermal power) are presented for a thermochemical plume ascending from the core–mantle boundary. In addition, the following relationships are developed: the pressure distribution in the plume conduit during the ascent of a plume, conditions for eruption-conduit formation, the effect of the P–T conditions and controls on the shape and size of a plume top, heat transfer between a thermochemical plume and the lithosphere (when the plume reaches the bottom of a refractory layer in the lithosphere), and eruption volume versus the time interval t₁ between plume formation and eruption. These relationships are used to determine thermal power and time t₁ for the Tunguska syneclise and the Siberian traps as a whole.

The Siberian and other trap provinces are characterized by giant volumes of lavas and sills formed a very short time period. Data permit a model for superplumes with three stages of formation: early (variable picrites and alkali basalts), main (tholeiite plateau basalts), and final (ultrabasic and alkaline lavas and intrusions). These stages reflect the evolution of a superplume from the ascent of one or several independent plumes, through the formation of thick lenses of mantle melts underplating the lithosphere and, finally, intrusion and extrusion of differentiated mantle melts. Synchronous syenite–granite intrusions and bimodal volcanism abundant in the margins of the Siberian traps are the result of melting of the lower crust at depths of 65–70 km under the effect of plume melts.     

Biodiversity and environmental characteristics of the bycatch assemblages from the tropical tuna purse seine fisheries in the eastern Atlantic Ocean

The impact of human activities such as fishing has been identified as a main factor in diversity loss in the open ocean. This paper studies the diversity patterns and environmental characteristics of the bycatch assemblages in Fish Aggregating Devices (FADs) and Free School sets (sets made on schools of tuna) from the tropical tuna purse seine fishery in the eastern Atlantic Ocean (35°W–15°E and 20°N–15°S). Data were collected from scientific observer programmes carried out between 2003 and 2011 on board Spanish and French fleets. The results showed different structure and diversity patterns of the bycatch assemblages depending on the fishing mode, with higher number of species and diversity found in FAD sets than in Free School sets. Bycatch assemblages showed preferences for specific oceanographic characteristics of the Atlantic Ocean, such as the equatorial and seasonal coastal upwelling systems, the Cape Lopez front system and the Guinea dome. The type of set and sea surface temperature play an important role to describe the diversity patterns of these species. These results confirm the importance of integrating different methods to study the marine ecosystem towards the correct implementation of the Ecosystem Approach to Fishery Management (EAFM).