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The relationships between circulation characteristics in the lower atmosphere of the Northern Hemisphere and the sunspot cycle are analyzed with the use of the superposed epoch method and elements of correlation analysis on the basis of data on the length of elementary circulation processes of different types (according to Dzerdzeevsky classification) and the time series of Wolf numbers for 1899–2016. It is ascertained that a general intensification of solar activity promotes an increase in the length of meridional forms of circulation, but its effect on different subtypes of elementary circulation mechanisms is different. Seasonal differences in the solar effect on the lower atmosphere are also revealed.

Parameters and combustion products of the Ti + C + cellulose nitrate porous granulated batch with added KCl, NaCl, or K2CO3 salts and/or C6H8Cl14 perchlorovinyl resin allowing for the evolved impurity gas filtration are investigated. The influence of these additives is shown and the formation conditions of nanostructured titanium carbide powder are found.

Nitrogen oxides, produced as a result of ionizing proton impacts, have long lifetimes and substantially affect the ozone balance. Photochemical models give an increased production level of nitrogen oxides during solar proton flares. The usage of an increased NO production effectiveness value (molecule number per each ion pair) during increased ionization of the atmosphere in models can be among the causes. This value has been estimated based on satellite observational data. Data on the solar proton fluxes and the composition of the atmosphere have been used. The period of the proton event of July 14, 2000, has been considered. The NO production effectiveness, obtained when the observational data were analyzed, was much smaller than the value obtained previously theoretically. The causes of these differences should be studied additionally.

Radioactive contamination affects soil organisms and causes profound structural rearrangements in soil zoocenoses, which are manifested in the decreased species diversity of invertebrate communities and low relative abundance of large soil invertebrates. However, these communities gradually recover their initial structure. The soil biota near the epicenter of an underground nuclear explosion performed 30 years ago in Perm oblast has been studied to reveal specific structural features of the soil macro- and microfauna. Its structural diversity is considered with regard to such components as species (taxonomic) composition, the structure of dominance, and the ratio of ecological and trophic groups.

Lands that have become unusable because of contamination with long-lived artificial radionuclides require special measures aimed at their monitoring and rehabilitation. In such areas, specific processes in the biota are associated with the direct effect of ionizing radiation on some species, secondary changes depending on the ecology of organisms trophically connected with these species, and side effects explained by the regime of isolation established in radiation reserves. The dynamics of floras and faunas in radiation reserves are determined by successional changes in plant communities, migration of radionuclides, and the protective status of these territories.

A preliminary study of soil macrofauna biodiversity in a set of ecosystems, from natural reserves to managed agroecosystems, provides indications that species number, population density and biomass decrease from natural ecosystems to agroecosystems. The main reason for the decrease appears to be a lack of available organic matter and essential element supply in the agroecosystem soil. However, biodiversity of soil biota as a whole is relatively close in agroecosystems and natural ecosystems if considered in terms of an index of genetic saturation (IGS). IGS is equal to the sum of S ( m j × k j ), where S is the sum of products mj and kj for species of a separate group of organisms ( S is equal to species number in the group), m j is the production of j -species and k j is the DNA concentration in this j -species. The main biodiversity pool is in the microbial biomass of any ecosystem. Maintaining biodiversity for a sustainable agriculture is connected with maintaining available organic matter and essential nutrient sources in the soil.

The fungi play a significant role in the biological turnover of elements and in the migration of elements along the food chain in ecosystem. Thus, when attempting the use of wild animals as bioindicators of the global fall-out of man-made radionuclides, sufficient amount of information must be obtained on the radionuclides content in the most different wild animal groups and also in plants, microorganisms and fungi.

The results of application of a high sensitivity methane laser detector to investigations of the methane concentration in the atmosphere over Baikal lake are presented as well as methane flows from the water into the atmosphere. The measurements were conducted at a stationary station and aboard the research vessel "Vereschagin" during two summer expeditions in 2003 and 2004. Mean background concentration was equal to (2.00+/-0.16) ppm in August 2003 and (1.90+/-0.07) ppm in June 2004. The areas of methane emission through the water's surface are found to be distinctly localized and to have a characteristic size of about 150-300 m in diameter. The methane concentration in the centers of these areas can reach approximately 27 ppm. Methane flows into the atmosphere in some Baikal regions were measured as well.

Anomolies in the atmospheric methane distribution over Lake Baikal have been studied with a diode gas analyzer having the threshold sensitivity of 0.04 ppm. Local areas, in which the methane concentration two to three times exceeded the background value equal to 2.00 ± 0.16 ppm, were detected.

Methane is the most important of organic substance in the atmosphere, and its concentration significantly exceeds the concentration of other organic compounds. The contribution from methane to the greenhouse effect is about 30 % of that from carbon dioxide. On the global scale, natural sources of methane are wetlands, rice fields, cattle, biomass burning, as well as gas-hydrates.The discovery of natural methane gas-hydrates sparked the increased interest in gashydrates and was followed by a series of investigations, by which enormous fuel reserves were discovered in the form of gas-hydrates stored in the bottom of the world ocean. Gas-hydrates attract a lot of scientific attention, not only because they can be used as fuel and chemical raw material, but also in the context of possible emissions of the methane into the atmosphere. Gas-hydrate crystals in Lake Baikal have been found quite recently. Lake Baikal is a convenient object for the investigation of gas hydrates and of gas vents at the lake floor. The aim of this work was to find anomalies in the methane distribution in the atmosphere over Lake Baikal surface using a high-sensitivity laser methane detector.The methane detector employs a GaInPAs diode laser as a source of radiation. The diode laser operates in the range from 6000 to 6080 cm-1 (1.645-1.666 µm), which includes rather strong absorption lines of methane. The detector was calibrated by a nitrogen-methane mixture with a methane concentration of 2.0 ppm. The detection limit (standard deviation) was 0.037 ppm, and time constant of the methane detector on the whole (with the allowance for the pump productivity and cell volume) was 99 s (spatial resolution of 450 m).The measurements of the methane content in the atmosphere over Lake Baikal were conducted by means of continuous air sampling from a height of 2-10 m above the water level from aboard R/V Vereshchagin in the periods of 10-16 August 2003 and of 16-24 June 2004. The coordinates of the measurement points were determined by the shipboard GPS system.Analysis of the data obtained in the course of the August 2003 expedition has shown that the methane concentration in near-surface air all along Lake Baikal averaged 2.001(0.16) ppm ; the standard deviation did not exceed 0.2 ppm. A distinctive and considerable (5.5 ppm) anomaly was observed near a shallow-water seep near the Selenga River inflow. Methane concentration distribution in near-surface air along the vessel’s track of 15 August 2003 showed a sharp peak that was limited in space and time.The average methane concentration in near-surface air over the South and Central Baikal Basins during the June 2004 expedition was 1.91(0.07) ppm and distinctive and considerable (more than 2.4 ppm) anomalies were observed at six areas in the Central Baikal Basin. Methane concentration distribution in near-surface air along the vessel’s tracks of 16-24 June 2004 was similar to the one obtained in 2003, with sharp peaks that were limited in space and time. Maximum air methane concentration (30 ppm) was detected near the Selenga shallow-water seep. In contrast to data obtained in August 2003 in the areas of visible methane escapes (Selenga River inflow and Babushkin village) groups of closely set methane escapes were observed. The distinctive and considerable (4 ppm) peak of the near-surface air methane concentration was observed near Mishicha, at a water depth of about 1000 m.The direct measurements of methane fluxes are very important for assessment of global fluxes of methane from water surface to the atmosphere. These measurements were carried out on vessel board for the first time. The most intensive fluxes (maximum methane flux was 2.12 E-9 kg/s m2) were observed near Babushkin village, where also maximum values of methane concentrations in near-surface water were detected. The typical magnitude of methane flux in most areas was within the limits of 1-3 E-12 kg/s m2. We also observed small inverse methan

In this paper we study the accuracy of wind retrieval from lidar data by spectra accumulation method (SAM) when turbulent fluctuations of wind velocity are present. Simulation of wind retrieval from space borne scanning Doppler lidar data by this method we carry out based on the real data of German Weather Service (GWS). For simulation of small scale turbulent fluctuations of the radial wind velocity we use GWS height profiles of zonal and meridional components of mean wind, temperature and turbulent diffusion coefficients of momentum and heat. The error of retrieval of wind velocity and direction from lidar data is calculated in dependence on turbulent velocity fluctuations variance for different heights (signal to noise ratios). This study was supported by the Russian Foundation for Basic Research (Grant N o00-05-64033).