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The emergence of plants with red leaves is related to accumulation of permanent anthocyanin pigments. Their temporary production under unfavorable environmental conditions is usually treated as an adaptive trait facilitating thermal stability and resistance to pests and diseases. The main pigment that is produced temporarily in almost all plant species is cyanidin monoglycoside. Using common barberry and its purple-leaf variant as a case study we found out that the predominant pigment in red leaves turns out to be the methylated derivative of cyanidin, namely peonidin-monoglycoside, although that does not alter the qualitative composition of anthocyanin pigments in red and green leaves. Ample accumulation of peonidin in the plants is shown to be inert with regard to basic functional properties: the plants continued to grow and bear fruits, though in different proportions. It is pointed out that more intense illumination leads to changes in energetic state of photosynthetic apparatus which are most prominent in the purple-leaf variant. Judging by the changes in fast fluorescence at different levels of illumination, red leaves at a low level of illumination utilize solar energy less efficiently by comparison with green ones.

The characteristics of dynamics of total nitrogen, potassium, and phosphorus content in the shoots of plants growing in plantations of different environmental categories in a large industrial center were studied. In the urban environment, an increased nitrogen content in plant shoots, the disturbance of the balance of the basic mineral elements and change in their distribution pattern in structural parts of plant shoots, and the disturbance of autumnal physiological efflux of elements from leaves to dormant shoots were detected.

The assessments of the carbon pool and rate of plant biomass production, phytodetritus destruction, new formations of humic matters, and removal of water-soluble decomposition products for the forest ecosystems of the forest tundra and the northern and southern parts of the Central Siberian taiga were given. The rates of the main processes (organic-matter production and degradation) were demonstrated to be balanced in the ecosystems of the forest tundra. The larch forests of the northern taiga serve as a stock for a C atmosphere, which are equivalent to 32-34% of net primary production (NPP). The secondary birch growth where the understory needle-leaved trees have been formed and the primary old-growth fir forests are characterized by the balance of the main carbon fluxes in the southern taiga. The birch forests where the understory trees are just being formed and the fir forests at the age of 50-90 years serve as a stock for an average of 26% of carbon extracted as dioxide to make NPP.

The individually oriented system of the EFIMOD models simulating carbon and nitrogen flows in forest ecosystems has been used for forecasting the response of forest ecosystems to various forest exploitation regimes with climate change. As input data the forest management materials for the Manturovskii forestry of the Kostroma region were used. It has been shown that increase of mid-annual temperatures and rainfall influence the redistribution of carbon and nitrogen supply in organic form: supply increase of these elements in phytomass simultaneously with depletion of them in soil occurred. The most carbon and nitrogen accumulation in forest ecosystems occurs in the scenario without felling. In addition, in this scenario only the ecosystems of the modeling territory function as a carbon drain; in the other two scenarios (with selective and total felling) they function as a source of carbon. Climate changes greatly influence the decomposition rate of organic matter in soil, which leads to increased emission of carbonic acid. The second consequence of the increase in the destruction rate is nitrogen increase in the soil in a form available for plants that entails production increase of plantations.

The analysis was made on 137Cs and 90Sr distribution oak, pine and hornbeam plantations depending on different under soil water levels. Intensity of 137Cs and of 90Sr migration along the vertical layers of soils is determined by under soil water level at a specific sampling site. The closer under soil water to the surface of the soil, the lowest radionuclide contamination is in the upper soil levels and the highest radionuclide contamination is in the deeper layers. The "fast" and "slow" quasi diffusion coefficients for 137Cs and for 90Sr and their contribution to the total migration of radionuclide through vertical soil levels were determined. A decrease in 137Cs and increase in 90Sr transfer factors to the elements of overground phytomass as a result of under soil water level lowering was established.

The examinations of allocation of radioactive isotopes of caesium and of strontium and of their chemical analogs in a stand of forest ecosystems are carried out. By results of examinations and analysis of literary data the presence of analogy in allocation of these elements on builders in quasi-balanced (concerning radionuclides) state was confirmed. The question about the opportunity of use of data about behaviour of K and of Ca is considered at an explanation of the mechanisms of redistribution of 137Cs and of 90Sr in wood plants and for buildup of mathematical models of behaviour of datas of radionuclides in ground ecosystems.

The dynamics of litter stock, microbial biomass, and composition and structure of microbial communities, were studied in the course of soil organic matter transformation during vegetation season. The dynamics of litter stock in coniferous and deciduous forests proved to correlate with the biomass and total abundance of microorganisms, particularly, with the proportion of microfungi in the microbial community.

The algorithm of display of 90Sr behaviour mechanisms in forest ecosystems by method of imitating modeling is developed. Distinctive features of algorithm: the 90Sr contents in vegetation is subdivided into two parts (outside and internal pollution), which dynamics is considered separately; dynamics of a radionuclide is considered in connection with dynamics of organic substance; it is supposed, that 90Sr behaviour in plants is similar to Ca behaviour; the biological availability 90Sr contained in a soil, is integrated function of time and physico-chemical properties of the given soil. On the basis of offered algorithm the model is constructed which is used for realization of a number of numerical experiments, including reconstruction of a situation of pollution of forest ecosystem on grey forest soils in result of Kyshtym accident. The quantitative estimations of intensity of 90Sr redistribution between stand components and soil are received. The modern problems of creation of prognostication models of 90Sr dynamics in the forest ecosystems are discussed.

Three samples of high-molecular-weight humin-like substances were obtained by solid-phase cultivation of Coriolus hirsutus and/or Cerrena maxima on oat straw. The yield of humin-like substances amounted to 1.38-2.26% of the weight of the plant substrate consumed. These substances, produced both by individual and mixed cultures of the basidiomycetes, were shown to be similar in their structure and physicochemical properties. According to the data of IR and 13C-NMR spectroscopy, the substances contained aromatic fragments and were close to soil humic acids. Studies of the dynamics of laccase production suggested that the humin-like substances were produced bia direct degradation of lignin macromolecules with direct involvement of extracellular laccase.

A model of 137Cs vertical soil transport by a tree root system is presented. As distinct from other models the radionuclide root uptake is described as a reversible process and depth distribution of roots is given as a function of time. The model was used for prediction of 137Cs release from a surface disposal site located in a territory with conditions similar to that in the Chernobyl NPP exclusion zone. Prediction indicates that during several decades 137Cs transport from the waste layer by the root system of pine can lead to significant contamination of the soil surface due to needles fallout and, probably, ionic leakage from roots.

Contamination of the southern taiga forests (Middle Urals) by discharges from cooper smelters (heavy metals combined with SO2) not only decreases the mean rate of decomposition of pure cellulose, but also radically changes the spatial structure of the destruction process. Heterogeneity of distribution of the destruction rate is sharply increased near the source of discharge due to differentiation of the space into microregions with high and low destruction rates. The characteristic size of spatial heterogeneity amounts to several tens of centimeters and the distribution of microregions with a high rate is accidental within several tens of meters. A hypothesis has been put forward that the described changes in the spatial structure of the destruction process are related, above all, to disturbed colonization of the substrate by soil myxomycetes.

In order to reduce the total enzyme consumption in high-solids static hydrolysis of nonwashed steam-exploded willow Salix caprea by mixed cellulase of Trichoderma reesei + Aspergillus foetidus, two different approaches were proposed. In the first case, the enzyme activity adsorbed on residual solids after extended hydrolysis was used for hydrolysis of the newly added substrate. The initial mixing of fresh and hydrolyzed substrates was sufficient for the adsorbed enzyme redistribution and conversion of the new substrate portion, and permanent mechanical stirring was not required. Feeding of two additional portions of the exploded hardwood adjusted to pH 4 with dry caustic into the reactor with simultaneous replacement of accumulated sugars with fresh buffer (pH 4.5) resulted, on average, in a 90% conversion of cellulose at the final enzyme loading 8 IFPU per g ODM substrate, an average sugar concentration of 12%, and a glucose/xylose ratio of 5:1. In the second approach, weakly adsorbed cellulase fractions were used for static high-solids hydrolysis followed by their ultrafiltration recovery from the resultant sugar syrup. In contrast to the initial cellulase mixture whose residual activity in a syrup did not exceed 5-10% at the end of hydrolysis (48 h), up to 60% of weakly adsorbed enzyme fraction could be separated from sugar syrups by ultrafiltration and then reused. Weakly adsorbed enzymes displayed a hydrolysis efficiency of not less than 80% per IFPU enzyme consumed in extended hydrolysis of pretreated willow as compared to the original enzyme mixture. An electrophoretic study of the weakly adsorbed enzyme fraction identified T. reesei cellobiohydrolase II as the predominant component, whereas clear domination of T. reesei cellobiohydrolase I was found by electrophoresis of proteins tightly bound to hydrolysis residual solids.

Dynamics of 137Cs specific activity (SA) in woody plants was examined. It was found that interseasonal variations of SA are connected mainly with precipitations and related oxygen in soil as well as Eh level. The rate of daily variation in SA in an individual tree can reach 19%. Acropetal or basipetal 137Cs distribution in the bole depends on physiological condition category (PCC) of a tree, weather and environment; SA ratio of higher and lower PCC depends on the same factors. In winter compared to summer higher SA correlation of tree separate parts was observed. Trees with 137Cs acropetal distribution in bark had proven lower general CA level.

The 9-years dynamic of Chernobyl-derived radionuclides in the vegetation and soil covers of the forest ecosystems of the European part of the CIS is considered. The quantitative estimation has been done for main fluxes of Cs-137 in the forests of automorphic landscapes: influx to the vegetation, return with the litterfall, stem flow and throughfall, vertical migration in the soil profile (including intrasoil flow), and redistribution within the system of geochemically connected landscapes.