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For theoretical description of interaction between geomechanical and physicochemical processes in multiphase coal seams, the author for the first time proves the existence of an analytic “extension” of the operator connecting Langmuir’s equation and the kinematic expression for pendulum waves in high- stress geomedia of hierarchical block structure.

The first results of the experiments on influence of fluid injection on the mode of interblock contact deformation are reported. It is found that deformation energy consumed to radiate seismic waves largely depends on parameters of fluid injected in fracture. Dilatant fluid appears to be the most efficient in the decrease of the seismic energy as the fluid viscosity grows with the rate of deformation. In the laboratory test, the slip-stick motion mode transforms into the quasi-stable creep in a single deformation cycle after fluid injection.

A new approach to local rockburst hazard problems and rockburst prediction is demonstrated in terms of acoustic measurements in two mine workings of Joint Kirov Mine, Apatit. The new approach is based on spectrum-correlation analysis of acoustic emission signals, on the one hand, and on the Griffith-Irwin fracture model, on the other hand. Acoustic emission signals are recorded using new-generation portable system Prognoz-L for local rockburst hazard monitoring. Prognoz-L provides digital recording and processing of a wide range of acoustic signal parameters. The analysis of spectrum parameters of the recorded signals confirms applicability of the innovative software/hardware system to predict dynamic events in rock masses.

The author studies stability of a structure (platform) on a pile foundation using physical modeling. Disturbing force is applied by a pendulum generating seismic impulse vibrations. The data on measured displacements of two points on the platform surface are used to find the platform incline under varied number of blows, blow energy, distance to the blow point and the platform weight.

The formulas and schemes are presented to determine the length of charges and their inert gaps. The calculations are based on the theory of superposition of seismic waves under blasting in rock mass. The proposed procedure enables calculating parameters of distributed charges under any ground and geotechnical conditions of blasting ensuring quality fragmentation, elimination of flyrock and reduction in drilling operations.

For the selective disintegration of kimberlite and dissociation of diamond crystals of undisturbed natural integrity, the authors have designed a tool with cutters having hardness lower than diamonds but higher than binding minerals in kimberlite. The article gives the results of testing the prototype of the heterogeneous material disintegrator on soft kimberlite extracted from Manchary pipe. The prototype includes disc brushes made of high-strength steel wire. The selective disintegration prototype is a preproduction model of lab, semi-commercial and commercial disintegrators. The method is applicable to recover hard particles from geological samples.

The researchers analyze energy processes running in an autonomous electric power system consisting of a synchronous permanent magnet generator and a semiconductor electrical energy converter. Current, voltage and capacity of key components of the system are evaluated, and the system operation modes are determined for the variable magnitude and character of applied load at the constant voltage output frequency. Parametrical law is proposed to control semiconductor converter serially connected to load and generating reactive power. The influence of the converter on the basic design parameters, energy specifications of the synchronous generator and the system as a whole are evaluated.

The data on carbon stock and its distribution on the main pools in the ecosystem are presented for mature pine forest bilberry type in the middle taiga. The ecosystem of mature pine forest bilberry type concentrates 158.2 t C ha^-1. Upper 1 m soil layer contribute 53 %, phytomass - 44, coarse woody debris - 3 % to total carbon stock. Net primary production is determined. Input of stand is 70 %, ground cover - 30 %. It is found active accumulation of wood. It forms about 36 % of biomass production. Litter fall and it distribution on separate fraction are characterized. Litter fall ranged from 1.13 to 1.53 t C ha^-1. It is equal 3-5 % of forest floor mass. The tree plants are generating the most part of litter weight. Needless and leaves play the key role in litter of stand. Inactive fraction (branches, cones) are characterized by big inter-annual variation in litter fall production due to changing weather conditions during study period. Dynamic soil temperature is described on lower boundary of forest floor. We estimate that during growing season carbon flux from soil surface is 2.28-3.21 t С ha^-1.

Identifying the best practices of responsible and sustainable forest use is an important aspect for possible learning of experience and replication of the most interesting examples in forestry. Qualitative and timely reforestation of disturbed areas with economically valuable species is the key indicator for the performance of effective forest management. Conservation of rare species of plants and animals in the logged areas is not less important factor. Today the priority is given to natural forest regeneration because it provides the best opportunity to avoid unreasonable financial costs and, as a rule, is more resilient against various natural and anthropogenic factors. The article discusses various examples and logging types in secondary forests in the Tomsk and Omsk Oblast, which allow increasing the economic, environmental, and social importance of forests. On specific examples it is shown that the principle of non-interference in the green zones of settlements is erroneous and may lead to undesirable consequences. The rejection of logging in these stands, as a rule, leads to increases of the fire danger, growth of phyto- and entomological threats, the reduction of recreational appeal, etc. The use of partial logging methods suggested in the papers has allowed solving some of these problems.

Forest litter is one of the major carbon flow and main source for long-term carbon accumulation in forest ecosystems. Wild fires is a frequent and powerful event destroys fluxes of matter and carbon accumulation. In the article the first data of stationary investigation of litter fall in flow and its organic matter content in larch forest (Larix gmelinii (Rupr.) Rupr.) are presented. The study is conducted on Tukuringra range in Upper Priamurie (Amur Oblast, Russia) in the forest stand recovering after fire of 2003 year. Results shows that net annual inflow of forest above ground litter fall from all vegetation in burned forest is 2.8 times lower than in background forest. Grass litter fall and other tree debris (bark, seeds, cones, etc.) are main sources for annual litter fall input in burned forest. Litter fall composition in the burned forest is significantly changed and high variation of mass of litter fall fractions is observed. Accumulation of carbon and nitrogen is higher in majority of litter fall fractions in burned forest as compared to control one. Annual carbon input from litter fall is 164 gm^-2 in control forest and 76 gm^-2 in burned forest, total amount of nitrogen derived by litter fall is 1.7 and 2.4 gm^-2 for control and burned forest respectively. Our findings suggest that carbon accumulation processes in fire-prone boreal forests changed significantly. The research results can be used for modeling of carbon balance in taiga forest damaged by fire.