About the mechanism of the granite-free zones formation in the Black Sea

One of the important unsolved problems related to the evolution of living conditions on Earth is the mechanism of the rapid transformation of the Black Sea from a shallow lake-type sea into a deep-water basin, the earth's crust in the central part of which does not have a granite layer. There is no explanation as to how “granite-free depressions” were formed at the bottom of the sea, which are currently covered by sediment. Investigations of these processes were started in the middle of the last century by scientists-geologists of the Institute of Oceanology of the Russian Academy of Sciences and its South. In this article, the authors propose a mechanism for the destruction of the earth's crust and the formation of depressions in the inner seas during the Messinian crisis.

Microplastics in the ocean: an overview and an outlook

The article provides an overview of scientific publications on the composition, genesis and distribution of microplastics in the ocean, as well as its effects on organisms and marine ecosystems. The most relevant areas of study of microplastics in the oceans are proposed.

Atmospheric circulation and variability of meteorological elements in near-shore Black Sea region

Effect of solar radiation and atmospheric circulation on variability of air temperature, atmospheric pressure, and rainfall in near-shore Black Sea region was examined. The action of the latitudinal position of trajectory cyclonic and anticyclonic movements and their times of occurrence in seasonal variability of meteorological elements was established. Three factor action on cyclonican and anticyclonic movement latitudinal position was determined. This is air temperature (year cycle), North-Atlantic oscillation, and lunar weather tides. Seasonal times of occurrence of cyclon and anticyclone, movements of southerly and northerly trajectories, and variability of atmospheric pressure and rainfall in near-shore Black Sea region was estimated.

Results of a secular study of some features of the biology of the muksun population Coregonus muksun of the Ob-Irtysh basin

Muksun spawned in the Ob River and its tributaries and overwintered in the river and in the Ob Bay, making various migrations. Under the influence of anthropogenic factors, there was a decrease in the number, to the threat of almost complete disappearance of the population. A retrospective systemic analysis of the peculiarities of the existence of the muksun population should become the basis for a strategy for its restoration and rational use.

Fiber-optic communication line application for towed underwater vehicles

Utilization of towed unmanned vehicles for seabed relief survey in real time requires the use of technologies that allow high-speed, stable data transfer between the underwater towed body and the carrier vessel. This paper discusses technical solutions used to provide a unified communication system based on fiber optic technologies for towed vehicles manufactured in Institute of oceanology.

Environmental risk assessments for contrasting Arctic shelf ecosystems

The article presents environmental risk assessments for two types of contrasting ecosystems of the Arctic shelf: highly productive and low-productive. Calculations were carried out using a probabilistic risk model with variations in the impact on the ecosystem from stressors, taking into account the risks from the technological processes of extraction and transportation of mineral resources of the shelf. Comparison of the results of risk modeling for highly productive and low-productive ecosystems showed that due to the low productivity of marine ecosystems, reliability requirements for technological processes ensuring the safety of resource development should not be reduced. The nontrivial conclusion obtained confirms the nonlinearity of the ecosystem response to impacts, which justifies the involvement not only of expert assessments, but also of all available methods, including modeling, to minimize the risks of Arctic resource development.

Effects of water hardness on the toxicity of heavy metals to Daphnia magna

The paper presents a comparative study of the toxicity of chromium and molybdenum, carried out in hard aquarium 0,14⁰Clark and soft natural 8,2⁰Clark waters. A decrease in water hardness leads to an increase in the acute toxicity of metals, which is expressed in a decrease in the values of semi-lethal concentrations by 3 times for molybdenum and 25 times for chromium.The results obtained show that the toxicity of metals can differ significantly in waters with different hydrochemical compositions. The data presented in the work can be used in the development of regional MPC standards.

Effect of spectral composition of light on the production characteristics of Arthrospira (Spirulina) platensis

The study of the growth of the batch culture of Spirulina platensis with different spectral composition of LED and luminescent radiation in plane-parallel photobioreactors was carried out. In the experiments, we used LED lamps LCD Feron LB-213 10 W, as well as fluorescent lamps TDM Electric 18 W. It has been shown that the maximum productivity of A. platensis does not depend on the radiation spectrum and is 0,25 g·l-1·day-1 at an energy of 45 W·m-2. In the linear phase of growth, the efficiency of light energy conversion (efficiency of photobiosynthesis) was calculated, taking into account that the culture absorbs 90% of the incident light: the maximum value was obtained for LED and fluorescent lighting (23 W·m-2 and 17 W·m-2 respectively), which turned out to be the same and amounted to about 3,78 %. The minimum efficiency of 2,69% is obtained with fluorescent lighting at 34 W·m-2.

Dynamics of the macromolecular composition of the biomass of microalgae in the morning under natural light. Model

The work is devoted to modeling the growth of optically dense microalgae cultures in natural light. The basic model is based on the idea of the two-stage photoautotrophic growth of microalgae. It is shown that the increase in the intensity of sunlight in the first half of the day can be described by a linear equation. Analytical equations for the growth of biomass of microalgae and its macromolecular components are obtained. As the initial conditions, it is assumed that at the time of sunrise, the concentration of reserve biomass compounds is zero. The simulation results show that after sunrise, the growth of the microalgae culture is due only to an increase in the reserve part of the biomass, while the structural part practically does not change over six hours. Changes in the ratio of the reserve and structural parts of the biomass indicate a change in the biochemical composition of cells.

What's wrong with the Kingdom of environmental journals?

The article analyzes the problems in ecological scientific Russian periodicals raised in the book by G.S. Rosenberg et al. “Space of eco-journals (a short guide for masters, postgraduates and others)” (Tolyatti: Anna, 2020. – 156 p.) Analysis of domestic environmental journals shows that they have low international ratings. To change the situation, it is necessary to develop tools to motivate scientists to publish articles in Russian periodicals. In addition, it is necessary to reform and strengthen the institutes of the Russian Academy of Sciences, conduct accelerated training of highly qualified scientific personnel through the expansion of postgraduate studies. The logs themselves should be more flexible and time-appropriate.