Home – Home – Jornals – Contemporary Problems of Ecology 2011 number 2

Investigations (starting from the first works of Laksman in early XVIII century) in the area of introduction of woody plants at the territory of the Asian part of Russia are anаlyzed. Special attention is paid to the major introduction centers of Siberia and Russian Far East. It is demonstrated that the first stage of tests of the species from different botanical-geographical regions helps only developing the assortment of woody plant species suitable for landscape construction and planting. Further investigations require more thorough and multi-aspect studies of trees and bushes under the conditions of primary introduction for the purpose of their actual introduction and use in creating artificial tree stands for various functionаl purposes (forest land reclamation, soil recultivation, preservation of rare and disappearing species of world flora etc). The importance of search for botanical and geographical regions that may become donors of aliens to be introduced on the basis of the climate-comparing method developed by us previously is stressed. It is recommended to organize introduction centers in Siberia and at the territory of Far East.

We investigated the variability of tree-ring growth and δ¹³C variations in Picea obovata L., Pinus sylvestris L., Populus tremula L., Betula pubescens Ehrh. tree rings, and anаlyzed the influence of climatic variables and reserve assimilates on these parameters. The correlation of tree ring width of studied species with climatic factors for the common time series shows both temperature and precipitation influence annual variability of tree ring width. Correlation coefficients of tree ring width for all species with climatic parameters indicate that annual variability of tree growth is mainly determined by June temperature. In addition to tree-ring structure, carbon isotope data provide important detailed information about the relations between tree growth and environment. Seasonal and inter-annual dynamics ¹³C has the same changes for all studied species and indicates the use of reserve assimilates. Tree ring carbon isotope composition could help to explain the assimilate redistribution process throughout the year and to determine the dependence of the radial growth on weather conditions.

Accumulation and distribution pattern of cadmium (Cd) and its toxic effect on growth of the mangrove plant of young Kandelia candel seedlings have been examined. This study demonstrated that under high concentration of Cd stress, the total biomass of K. candel decreased 41.57 % compare to control (CK). At the end of 90 days exposure to 25 mg L^-1 Cd, the average seedlings stem height and leaf number of the K. candel decreased by 30.54 and 42.68 %, respectively. The results showed that K. candel seedlings, under the experimental condition, accumulated higher concentration of Cd in their roots (411.29 ± 3.60 mg kg^-1) when compared to hypocotyls, stems and leaves. More than 95 % of Cd was accumulated mainly in roots. The distribution pattern of Cd concentration in K. candel seedlings was found in the following order: roots> hypocotyls > stems > leaves. Based on the leaf symptoms and morphological change of K. candel seedlings under heavy metal stress, this study showed that Cd is phytotoxic to K. candel.

Results of the investigation of radial growth of Larix cajanderi Mayr and Pinus sylvestris L. in Central Yakutia are presented. The time span of the set wood ring chronologies is more than 200 years. The application of dendroclimatological methods in studying tree growth within the range of permafrost rocks allowed us to reveal their close interconnection with climatic factors and hydrothermal conditions of soils. A significant correlation between ground temperature and humidity at different depths with the radial growth of larch and pine in Central Yakutia was revealed for the first time by means of statistical anаlysis.

The article presents the results of the study of lichenflora species variety of Khanty-Mansy autonomous okrug, represented at present by 958 species of 199 genera and 72 families. Among them, Cetrelia alascana (Llano) W. L. Culb. et C. F. Culb. have been determined for the first time for West Siberia, 3 species - Graphis elegans (Borrer ex Sm.) Ach., Porpidia hydrophila (Fr.) Hertel et A.J. Schwab., Sclerococcum sphaerale (Ach.) Fr. - for the first time for Siberia, and 4 species - Acarospora fusca B. de Lesd, Cliostomum tenerum (Nyl.) Coppins et S. Ekman, Pertusaria corallina (L.) Arnold, P. stalactiza Nyl. - for the first time for Russia. Ecological dependence of species composition of the lichenflora was anаlyzed.

Regularities of alpine vegetation structure of the Ko Mountain are described based on the specificity of natural and climatic conditions and development history of this territory.

Data on the distribution of eight wild-growing berberry species in the botanical-geogrpahical regions of Tadzhikistan are reported, as well as the information about the altitudinal limits of growth and florocoenotypes in which these species are included.

Introgressive hybridization between Larix gmelinii and Larix cajanderi is investigated. The data obtained confirm indisputable species self-dependence of Larix cajanderi that occupies about 48 % of the whole area of larch forests in Russia. Its species self-dependence was called in question by some researchers until the recent time. Once more, at a more reliable and extensive material, we demonstrate the presence of a broad transient band of hybrid populations at the junction of hybridizing species. Some forestry features of Larix gmelinii and Larix cajanderi playing important part in their natural renewal are studied.

Possibility to use the risk analysis technology for ecological evaluation of desertification is demonstrated. Such risks are estimated quantitatively per year: specific physical year (year^-2), full physical (ha/year), economical (roubles/year), social (persons/year), and the function of stability (reliability) of land under desertification is determined.

Effect of some pollutants on Hypogymnia physodes lichen is investigated. It is established experimentally that most changes in the chemical composition of the lichen are caused by short-duration action of 32 and 65 % nitric acid and long-duration action (14-21 days) of low-concentration sulfuric acid (3 and 6 %).

Stability of a number of woody plants of West Siberia against toxic compounds - sulphur dioxide, hydrocarbons and carbon black - was studied on the basis of the reaction of pigment complex, changes of the acidity of leafs, activity of oxidative enzymes, water schedule and degree of leaf damage. These studied may be applied in planting green areas in sanitary-buffer areas of enterprises.

Plants of 76 species from 25 families, growing in the forest-steppe zone of Western Siberia, are investigated for the content of low-molecular biologically active substances - flavonoids, tannins, cathechins, coumarins, saponins, аlkaloids. It is established that 33 species are perspective as a source of flavonoids, 29 species - tannins, 21 - coumarins, 13 - saponins, 13 - аlkaloids and 1 - cathechins. Habitats and terms of gathering plants with the high flavonoid content are presented. It is revealed that the largest amount of low-molecular biologically active compounds is present in the representatives of Asteraceae, Lamiaceae, Rosaceae families.

For the example of the active volcano Mendeleev at the Kunashir island, it was discovered that the emergence of volcanic gases and acidic thermal water on the surface affects the geochemical features of soil and vegetation in the surrounding landscapes. Some species grow on hot substrate, accumulate heavy metals, rare and scattered elements with which the parent rocks are enriched, and conserve full vitality. It is demonstrated how adaptation to specific ecological conditions occurs in woody plants at the anatomic level in the sites of emergency of volcanic gases and thermal springs.

Investigation of the biology of Russian olive (Elaeagnus angustifolia L.), a rare introduced plant is presented. Questions of its seasonal development, fruiting pattern and quality of ripe seed are the concern of the article.