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Using RAPD and ISSR analyses, the genetic diversity and population structure of Isoetes lacustris L., a relict representative of aquatic flora confined to oligotrophic lakes and experiencing sharp population decline in Europe, was analyzed in Belarus, on the southern border of species range. For the four studied populations, a total of 127 markers were identified (90.6% polymorphic, 83.5% informative). At the species level, the genetic variability parameters were He = 0.247, Pp = 100%, and I = 0.390. A medium level of subdivision (φPT = 0.269, p ≥ 0.001; Fst = 0.193, p ≥ 0.0001) and genetic exchange (2.7 migrants per generation) was revealed. A higher proportion of total genetic variation (73.13%) was found within populations, 13.36% of variation was found between populations, while 13.51% explained the differences between the regions (southern and northern populations). Ordering of populations by genetic diversity (He = 0.063–0.243; Pp = 17.92–93.4%; I = 0.095–0.379) and identification of individual loci determine the uniqueness of each population and its importance for formulation of conservation programs. A decrease in the level of genetic diversity in small isolated populations in combination with limiting factors (natural factor—southern distribution limit; anthropogenic factors—eutrophication and changes in the lake regime) poses a threat to the populations’ survival and distribution of the species in Belarus. Based on integral analysis of the ecological and phytocoenotic characteristics of I. lacustris habitats, and the level and structure of the genetic diversity of its populations, measures for in situ and ex situ conservation of the species are proposed.

The paper completes a series of works about the unique Schlema-Alberoda deposit. The data on sources of vein and ore minerals and their relation to the processes of regressive alteration of rocks from the contact metamorphism zone are refined. The correlation between stages of mineral formation and their directed change are shown. A general scheme for the sequences in formation stages of the deposit’s hydrothermal ores is oriented on a joint analysis of geological and mineralogical–geochemical evolution of potentially ore-bearing provinces.

As a result of integrating geological, mineralogical, and geochemical data on the unique Schlema–Alberoda five-element uranium deposit situated in Federal Republic of Germany and explored in detail down to a depth of 2 km, it has been shown that its formation for more than 100 Ma has been caused by combination of internal and external factors. The latter comprise favorable metallogenic specialization of the region, injection of intrusive bodies bearing the necessary stock of energy, and periodic pulses of tectonic reactivation. The internal factors of self-development involve evolutionary processes, which occur in host rocks at the consecutive stages of prograde and retrograde metamorphism giving rise to alteration of rocks in consistence with physical and chemical laws at variable temperature and degree of system opening.

The paths of the movements of hydrothermal solutions are considered in the case of one of the world’s largest uranium vein deposits, the Schlema-Alberoda, which was mined by the Soviet-German corporation Wismut JSC in the second half of the 20th century. Detailed geological exploration to a depth of 2 km was accompanied by specialized research, the results of which have remained practically unpublished due to confidentiality. The data obtained show that the region adjoining the largest fault was draining rather than ore-conducting. This circumstance specifies and supplements the current concept concerning the movement of hydrothermal fluids.

The domal structures of the Erzgebirge in Saxony, Germany, which control localization of the Variscan hydrothermal U, Sn, W, and base-metal deposits, started to form in the Late Riphean in the course of folding, regional metamorphism, and granitization and were eventually created at the end of the Paleozoic, when an enormous mass of granitic melts was emplaced and cooled. As is illustrated by the world’s largest Schlema-Alberoda vein uranium deposit, the fractures that determined the localization of ore-bearing veins were formed in the outer contact zones of the Variscan granites related to domal uplifts. Beyond the zones of contact metamorphism, the orientation of ore-bearing fractures changes, their morphology simplifies, the amplitude of displacements decreases, and most fractures pinch out. Such a zoning is explained by development of faults around growing granitic domes.