Influence of Hydrologic Conditions of the Lower Ob Floodplain on Reproduction in Coregonids

The influence of the water level in the period of the open river channel and the duration of lower floodplain inundation on the feeding conditions, abundance, and population state of coregonids in the Lower Ob was investigated. The long-term dynamics of catches of some coregonid species was analyzed and compared with changes in the hydrologic conditions in the floodplain. The relationship between basic hydrologic conditions in the Lower Ob (water level in the period of the open channel, the duration of the lower floodplain inundation), the coregonid population sizes, the state of spawners, and the size of catches is demonstrated.     

Changes in the Carabid Fauna (Coleoptera, Carabidae) of Meadow Steppes during the Past Decades

Basic trends in the structural dynamics of the meadow-steppe carabid fauna over the period from 1970 to 1997 have been analyzed. Data on changes in the abundance and composition of dominant species are reported. Transformation of carabidocenoses is mainly accounted for by an increased humidity of the climate and the related mesophytization of forest–steppe ecosystems.     

The role of floods in the Long-term dynamics of geobiont and chortobiont communities on islands of the Kuibyshev Reservoir

Interannual changes in geobiont and chortobiont abundance on the islands of Kuibyshev Reservoir are largely determined by flood conditions, because the seasonal average abundance of many taxa is negatively correlated to the water level in May and June. Floods influence the abundance of these animals both directly and indirectly, through biocenotic connections and some aspects of behavior. Long-term positive trends are observed in the abundance of many species. The hypothesis is proposed that this increase in the abundance of geobionts and chortobionts is a consequence of adaptation processes in these communities, which are stimulated by the flood regime of the reservoir.     

Changes in plankton abundance, biomass, and chemical composition under the influence of the cooling system of the Beloyarsk Nuclear Power Plant

The abundance and biomass of phytoplankton and zooplankton proved to noticeably decrease after the water passed through the cooling system of the Beloyarsk Nuclear Power Plant: the phytoplankton perished by 38% (65 metric tons per day), and the zooplankton, by 55% (6 t/day). In the period between 1985 and 1991, the concentration of⁶⁰Co in the plankton of water intake and discharge canals varied from 120 to 1400 Bq/kg dry weight, and that of¹³⁷Cs, from 150 to 1040 Bq/kg dry weight, which is commensurable with the content of radionuclides in the plants and grounds of the Beloyarsk reservoir. In 1985, it was noted that the plankton passing through the cooling system of the nuclear power plant became enriched with Ca, Fe, Mg, Mn, Co, Cs, Cu, Mo, Ni, Pb, Si, Sn, Ti, V, and W.     

Changes in Species Diversity of Rove Beetles (Coleoptera,Staphylinidae) Depending on the Age of Pine Plantations in Central Belarus

Trends of changes in species richness and dominance in staphylinid communities depending on the age of pine plantations have been analyzed. The species richness of these communities is high in the plantations of age classes 1 and 2 (11 and 28 years, respectively) but decreases in the plantations of age class 3 (60 years). The highest and lowest indices of species diversity are observed in the plantations of age classes 2 and 3, respectively. Four groups of rove beetles have been distinguished by the criterion of their dominance in pine plantations of different ages.__________Translated from Ekologiya, No. 4, 2005, pp. 306–313.Original Russian Text Copyright © 2005 by Derunkov.     

Specificity of Life Conditions for Commercial Invertebrates on Artificial Substrates in the Eutrophicated Amur Bay,the Sea of Japan

The consequences of anthropogenic impact on the water area of Amur Bay (the Sea of Japan) near Vladivostok include the eutrophication of coastal waters and littering with various objects used as artificial substrates, which protect sedentary animals from predators and contribute to the survival of their larvae. An indicator of eutrophication, the diatom Skeletonema costatum accounting for 81–96% of the total abundance of phytoplankton (Stonik and Selina, 1995), is consumed mainly by barnacles and the Pacific oyster. Thus, these animals gain an advantage in the colonization of artificial substrates. The results of the study suggest that eutrophication will lead to changes in the structure of the marine community.     

On the Biology of Five-toed Pigmy Jerboa (Cardiocranius paradoxus Satunin, 1902) in the Ubsu-Nuur Depression

Russian Journal of Ecology -     

On the Biology of the Five-Toed Pygmy Jerboa (CARDIOCRANIUS PARADOXUS Satunin, 1902) in Kazakhstan: New Data

Russian Journal of Ecology -     

Ecological Connections between Gamasid Mites (Arachnida,Gamasoidea) and Small Mammals in Forest Biotopes of the Middle Volga Region

Host specificity of mites with respect to different species of small mammals in forest ecosystems was studied. The preferences of some parasites for certain host species differed from those described previously. In some cases, most parasites preferred to feed on the species that were most numerous in a certain biogeocenosis, rather than on their specific hosts. Conversely, other species of mites fed mostly on their specific hosts, irrespective of their low abundance, thus manifesting close connections with these mammals. Two mite species, Myonyssus dubinini and M. rossicus, were found in the study region for the first time.     

Influence of the zebra mussel and fish fry on structural and functional characteristics of microorganisms in experimental ecosystems

The interactions of zebra mussels, invertebrates, fish, and microorganisms were studied experimentally. Trends in the distribution of total bacterial biomass, the abundance of heterotrophic organisms, and their functional activities in water and grounds were analyzed. The most favorable conditions for development of bacteria developed in June, in the presence of fish and without zebra mussels. In experimental ecosystems with zebra mussels, a decrease in the abundance and activity of microorganisms and a change of dominant yeast forms were observed.     

Global Warming-Related Dynamics of Infection by Eubothrium rugosum (Plathelminthes,Cestoda) in the Burbot from the Rybinsk Reservoir

Russian Journal of Ecology - Abstract—Long-term observations (1968–2019) on the dynamics of infection by the cestode Eubothrium rugosum in the burbot (Lota lota) have been performed in...     

Effects of ecological factors on the diurnal activity rhythm of Yakutian black-capped marmots (Marmota camtschatica bungei) in the arctic

It is established that the activity of marmots (the genusMarmota) on the surface is timed to the daylight period. In the Arctic, under conditions of continuous illumination (the polar day), the diurnal rhythm of black-capped marmotsMarmota camtschatica bungei on the surface has a “daylight” pattern. The main external regulator of the diurnal rhythm is the altitude of the sun above the horizon. In the cold period, however, the effect of air temperature on animal activity becomes stronger.     

Heavy Metals in Organs and Tissues of the European Black Vulture (Aegypius monachus): Dependence on Living Conditions

The distribution of Fe, Zn, Cu, Cd, Mn, Pb, and Ni in the organs and tissues (kidneys, liver, lungs, brain, heart, muscles, and feathers) of the European black vulture (Aegypius monachus) was studied. It was shown that heavy metals were not responsible for the mass mortality of these birds in southern Primorye in the winter of 2001–2002. The level of pollution with heavy metals of the range of European black vultures wintering in this region (northern China and western Mongolia) may be regarded as insignificant.     

Effect of Climatic Factors on the Growth of Representatives of the Genus Pinus (Pinaceae) under Conditions of Introduction

Four introduced and one aboriginal species of the genus Pinus L. have been studied in the middle taiga subzone of southern Karelia. Significant interspecific differences in the dates of onset, cessation, and peak of the growth of shoots and needles have been revealed. It has been shown that their annual increment depends on the rate of growth, rather than on its duration. The dynamics of shoot and needle growth in introduced and aboriginal species, though largely similar, differ in some respects. These differences reflect species-specific responses to hydrothermal conditions in a certain growing season.     

Long-term Dynamics of Pike Infection by Parasites Triaenophorus crassus and T. nodulosus (Plathelminthes,Cestoda) in the Rybinsk Reservoir: Effect of Hydraulic Construction and Climate Warming

Russian Journal of Ecology - The long-term dynamics (over more than 70 years) of pike infection by cestodes Triaenophorus crassus and T. nodulosus in the Rybinsk Reservoir (the Volga River) has...     

Variation in the Parameters of the Life Cycle in Prawns of the Genus MacrobrachiumBate (Crustacea, Palaemonidae)

Variations in the parameters of the life cycle in freshwater prawns of the genus MacrobrachiumBate and some populations of the species Macrobrachium nipponense(De Haan) were analyzed comparatively. Using factor analysis, these parameters were systematized and expressed through two factors. The first factor is related to the parameters of larval development and the dimensions of an egg, and the second, to the length of adults and their fecundity. The greatest differences in the values of intrageneric and intraspecific variation of parameters are noted for the dimensions of larval stages. It is assumed that the formation of a species proceeds primarily through the appearance of adaptations at larval stages.