Home – Home – Jornals – Siberian Journal of Forest Science 2018 number 3

The subject of the study is the relationship between growth of lateral shoots and pine needles. A methodical approach to the mathematical-statistical processing of biometric data is used, which supplements modern methods of analysis. The approach makes it possible to identify both linear and nonlinear relationships between directly measurable characteristics in the form of formula relations, the set of which facilitates the formation of ones own conceptual models or the verification of known ones and helps identify morphometric characteristics that are essential for modeling the studied processes. The presence of the following relationships is established: the inverse dependence of the length of the needles on its density (the number of needles pairs per unit surface area of the auxiblast); the dependence of the length of the auxiblast on the «development» of needles (the product of the number of needles pairs by the length of the needles); the dependence of the number of needles pairs on the shoot and the length of the current year’s shoot from the value of shoot increment of the previous year; the relationship of «development» of needles with the ratio of axial and radial dimensions of the shoot. A positive correlation between the remoteness from the flame and the magnitude of the coefficients in the formula specifying the latter relationship allows one to make supposition on the effect of temperature increase on the relative redistribution of the auxiblast biomass over radial or axial increments. An analysis of the formulas obtained indicates a significant relationship between radial and axial growth processes with «development» of needles, as well as their conjugation with the state in the previous year, and the effect of a gas flame on them.

The research was carried on in even-aged Gmelin larch trees ( Larix gmelinii (Rupr.) Rupr.), growing in permafrost conditions of the north and south facing slopes (Central Siberia, 64°19′23″N, 100°13′28″E). 13 even-aged larch trees growing in the north facing slope and 5 ones growing in south facing slope were selected. Tree ring widths were measured at 1/4, 1/2, 3/4 of the stem height and at beneath apex. The sliding response functions were calculated in the common period 1974-2009. It has been revealed negative trend in the variation of the mean tree ring widths along the stems of the trees growing in the north facing slope. Indexed radial increments at higher levels in the stems (3/4 of the stem height and just beneath apex) of these trees correlated negatively with air temperature in the third decade of April as well as positively correlated with this climate factors from the 20-th of May to the middle of June. In the south-facing slope the similar correlations were not revealed. In the north facing slope, with the correlation of those measured just beneath top of a tree with precipitation in the third decade of May was especially notable. These tendencies were considered as circumstantial arguments in favor of Gmelin larch trees growing in the north facing slope experienced harsh water deficiency from 20-th of May to the middle of June. Water deficiency could reduce water potential of tree tops, which could be responsible for their drying off.

The aim of this study was to investigate the change of pigment complex and biochemical parameters of the Siberian larch Larix sibirica Ledeb. needles in the various functional zones of Ulan-Ude city (Republic of Buryatia, Russia). Using a scanning electron microscope with an energy dispersive X-ray spectroscopy (EDS), the size, distribution and chemical composition of individual particles were examined on the surface of needle discs of the Siberian larch . The majority of particles (40-50 % of the needle surface) were observed on the needle from traffic zone of city. In the residential part of the city, in urban parks and squares, the particles occupied 20-30 % of the needle surface. Single particles were found on the needle from background part. Chemical composition indicated that the most particles were soot and dust with minor constituents such as Si, S, Fe, Al, Cu, Zn, W, Ti, Ca, Сl, Cr, Ni. Much higher concentration trace metals exceeding background levels in 1.4-7.7 times were found in needle from traffic zone. Accumulation of pollutant elements in needles leads to activation of antioxidant protection. The amount of photosynthetic pigments in needles increases by 1.5-2.2 times compared with background values, mainly due to chlorophyll b and carotenoids. Ratio of сhl. a / chl. b , and also chlorophylls to carotenoids decreases by 13-26 %. Proline content increases 1.6-7.5 times, ascorbic acid - 1.2-1.3 times, catechin and proanthocyanidins - 3.0-4.8 times. The highest concentrations of these compounds were found in the traffic zone of the city.

Based on experiments of forest fire modeling conducted in 2000-2003 for the first time in Siberia, long-term monitoring of impact of various intensities fires on Scots pine stand components and post-fire succession was conducted. The most significant postfire transformation of all Scots pine stands components was revealed after high-intensity fires. The relationship between tree mortality and fire intensity was established. The estimation of initial post-fire succession, change of composition and structure of grasses and small shrubs as well as pine regeneration was provided. The relationship between phytomass consumption and fire intensity was established. Aboveground phytomass decreased after fires of low intensity by 5-10 %, and after high-intensity fires - by 74 %. The greatest accumulation of ground phytomass occurs in the first postfire years, which is associated with the intensive tree mortality during this period. Due to tree mortality, mortmass (duff, down woody debris) increased after high-intensity fire more than two times. After the fires, the redistribution of the living biomass to mortmass occurs, with highest changes found after high-intensity fires. The relationships between phytomass accumulation and fire intensity and time since fire were obtained for southern and central taiga Scots pine stands. The investigation conducted allows to forecast impact of fires of various intensities on forest components, post-fire succession and reforestation of Siberian Scots pine stands based on data on prefire pine characteristics and fire intensity.

The data of experimental studies on the effect of final felling and forest fires on the changes in water regulation and soil protection functions of larch forests in Northern Mongolia are considered. The results of snow surveys on felling and burns in pseudo-taiga and subtaiga larch forests of Central Khangai and East Khentey are analyzed. It was revealed that in the conditions of winters with little snow, the forests are snow accumulators and can significantly affect the replenishment of spring moisture reserves and the moisture regime of soils. During the melting of snow, the runoff in the forest starts 2-4 days later than on logged and burned areas. It is established that, in contrast to the mountain forests of Siberia, the Urals and the Far East, the water-controlling role of forests in Mongolia is most clearly expressed in the warm season, when the main amount of precipitation falls and the maximum annual runoff of rivers is formed. At this time, the forest largely prevents the formation of surface runoff, contributes to a more uniform groundwater supply of rivers and is a powerful anti-erosion factor. In the forest, the surface run-off in summer usually does not exceed 0.6 % of the total precipitation. The negative effect of conditionally final and final felling and ground litter-humus fires on changes in stocks, the qualitative fractional composition of forest litter and their moisture capacity, and also the water-physical properties of soils is shown. On logged and burned areas soil density increases, total porosity decreases, the range of active moisture decreases and the water holding capacity of the upper soil horizons decreases. Quantitative indicators of summer liquid and solid matter surface runoff formed on logged and burned areas in larch forests of Central Khangai and East Khentey are given. Anthropogenic destruction of forest ecosystems inevitably leads to their degradation, the restoration of which takes many decades.

In the study, based on the analysis of literary sources and the own research materials, the characteristic of the environmental situation in Taimyr is done, in connection with aerial technogenic impact of the Norilsk mining and smelting complex (NMSC). The dynamics of forest condition over the past decade in the area within 200 km or more from the complex is evaluated. The analysis was performed taking into account the landscape structure of the territory. The progressive drying of the large areas of the northern forests since the early 80’s is registered. The dendroclimatic analysis of the increment of older larch trees in the zone of the NMSC impact, implemented by the method of revealing the main factors influencing the increment, showed that since the beginning of the 20^th century, the instability of the increment of wood has increased due to the sensitivity of this tree species to changes in the temperature conditions of growth. To assess the extent of forest damage, an aerial survey was conducted in July, 2003, as a result of which zoning of the territory adjacent to the NMSC was carried out according to the degree of damage to the stands: dead stands, severely damaged stands and moderately damaged stands. An estimation of the productivity of stands and the degree of their damage by landscape locations was made. The negative role of sulfur compounds was assessed and contemporary measures for sulfur utilization were described.

For natural pine forests in the southern part of the Primorsky Krai, an assessment of biological diversity has been performed based on the results of descriptions of valuable tree species, living ground cover and carabid beetles Carabus . Field work was carried out on the trial plots laid in the forest plantations of the pine and broad-leaved forest with the domination of Korean pine Pinus koraiensis Siebold & Zucc. Model sites contained a chronological sequence of development of forest plantations of fresh small-grass and different-bush type on the interval of age 50-200 years. In the process of reforestation, a decrease in the total projective coverage of living ground cover was observed, while the number of species characteristic for natural pine forests, as well as their leveling, increased at the same time. By the age of 200 years species richness and leveling of the number of ground beetle species have reached a maximum. Statistically significant difference was found between the total number of caught insects in the plantations of 50 and 200, 80 and 200 years. The most valuable in terms of biological diversity are the old-growth pine forests. A conclusion was made about the value of this group of forests for the protection of valuable communities and habitats of species. Among ground beetle species Carabus schrencki Motschulsky, Carabus maacki Morawitz and Carabus macleayi Dejean can serve as an indicator of forest value. With a minimum total projective coverage (8.3 %), 200-year-old pine forests are favorable for the growth of such characteristic species as the mountain peony Paeonia oreogeton S. Moore, pale-mountain Dryopteris crassirhizoma Nakai, and the Pale Indian Plantain Cacalia auriculata H. Rob. & Brettell. On this site the Shannon index of species of living ground cover was 3.6, the Carabus species is 1.4.

The area of drained lands after peat mining in Russia is about 1 million ha and in Belarus 200 thousand ha. The lands after peat mining have poor fertility and different environmental characteristics. Successful forest planting on this lands are limited by high acidity, low depth and decomposition of peat layer and bad availability of mineral nutrients. One of the perspective directions is creation of short rotation coppice plantations of trees, such as willow, poplar and black alder. The wood of those trees may be used as a renewable source of energy. The purpose of our experiments was to estimate an efficiency of creation short rotation willow coppice plantations on the lands after peat mining. Experiments were conducted in Grodno Oblast of the Republic of Belarus. Experimental plots were planted on four types of soils with different layer and decomposition of peat and different agrochemical characteristics. Willow plants on the plots with shallow peat layer with bad peat decomposition were growing slowly and the height of plants after three years (the time of harvesting) was about 2-2.5 m. Height of willow plants on the plots with deep peat layer and with good decomposition and structure of peat after three years was 4-4.5 m. The yield of wood from these plots was 9-10 ton per ha per year in dry matter calculation. This yield was not much lower with compare to yield of willow on mineral soils. The wood from plantations (10 ha of area) were using by peat factory as a renewable biomass for energy. It is possible to increase yield of willow on the base of introduction species, which are adapted to wetlands like Salix dasyclados Wimm . The productivity of Salix dasyclados in our experiments was higher to compare to Salix viminalis L., which usually is used for selection of fast growing clones. The acidity of wetlands decreased on 0.30-1.05 pH after application of 10 tons of peat and it amounted to 5.95-6.25 pH in depends of variant.

Arthur G. Krylov - doctor in biology, well-known specialist in geobotany, typology of Siberian forests, developed the classification of the Siberian stone pine forest types and generalized classification of forest life forms in the North Eurasia. The mountains of Altai, Far East and Caucasus, the West-Siberian plain forests, were studied during his long expedition life.