[Acceleration of Embryonic Development of Pinus sibirica Trees with a One-Year Reproductive Cycle].

The study of the formation of embryonic structures in Pinus sibirica forms with a one-year reproductive cycle showed that the acceleration of the embryonic process manifested itself as a reduction of the coenocytic stage of the female gametophyte development (1.5 months instead of 1 year). The egg was not fertilized because of the asynchronous maturation of male and female gametophytes. Seeds without embryos were formed. We assumed that the acceleration of the reproductive process in Pinus sibirica was caused by a mutation in the female generative organs.

[Effect of emissions from a copper-nickel plant on soil microbial communities in forest biogeocenoses of the Kola Peninsula].

The effect of industrial pollution with emissions from the Severonikel Copper-Nickel Plant (SCNP) on soil microbial communities of forest biogeocenoses has been studied taking into account their relative location under tree crowns (near the stem, in the undercrown area, or under gaps in the canopy). The results show that increasing technogenic pollution results in a significant decrease in the microbial biomass, basal respiration, and maximum specific growth rate, as well as in dominance of K-strategists in the microbial communities of polluted soils. The effect of location under the crown, compared to the intercrown area, manifests itself in dominance of rapidly growing microorganisms with the r-strategy. However, emissions from the SCNP inhibit the growth of r-strategists, and the location-dependent differences between microbial communities are leveled off in areas with the highest pollution level.

[Features of microorganism distribution in the Al-Fe-humus podzol of the northern-taiga spruce forests: natural and technogenic aspects]. / Osobennosti rasprostraneniia mikroorganizmov v Al-Fe-gumusovykh podzolakh severo-taezhnykh elovykh lesov: prirodnye i tekhnogennye aspekty.

Natural and anthropogenically induced seasonal variations in the abundance and biomass of various groups of microorganisms in the Al-Fe-humus podzols of boreal spruce forests were analyzed. The fungal biomass in these soils was found to be considerably higher than the bacterial biomass. Microbial population was mainly concentrated in a thin surface layer (10-15 cm in thickness), which included the forest litter and the upper mineral root-inhabited soil horizon and greatly differed from other soil horizons in morphology and other properties. This layer was found to be optimal with respect to hydrothermal and nutritional conditions and was characterized by profound seasonal variations in the abundance and biomass of microbiota. The high acidity, typical of the Al-Fe-humus podzols, resulted from the metabolism of their microbial communities. In the polluted podzols, the population of prokaryotes increased and that of eukaryotes decreased.