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1.
The effects of hydrothermal conditions on the complexes of soil invertebrates in 20-year-old cultures of Siberian stone pine, larch, Scotch pine, spruce, birch, and aspen are considered. The role of soil temperature and moisture content in determining the density of pedobionts and their vertical distribution is revealed. Seasonal fluctuations of hydrothermal parameters are shown to affect the vertical migrations of soil invertebrates and the dynamics of trophic structure of their complexes under forest cultures during the growing season.  相似文献   

2.
Morphophysiological and anatomical characters of needles that are used for characterizing infraspecific taxa have been studied in Scotch pine geographic cultures established in the forest-steppe zone of Siberia. Variation in these characters has been revealed, which reflects the polymorphic structure of the species and the effect of natural selection on the composition of populations in new natural-cimatic conditions.  相似文献   

3.
Cytogenetic variation was analyzed in daughter populations of Scotch pine from the Voronezh Forestry. The dependence of the variation on the method of seed collection (the commercial method; the population method, when seeds from a group of phenotypically normal trees in the center of the forest are collected; or the individual method, when seeds from plus trees are collected) and on the ecological situation at the sampling site (ecologically safe conditions or chemical or physical pollution) was studied. The parameters of the mitotic rate and mitotic pathology were estimated at 7–9% and up to 5%, respectively. These parameters may be considered as normal when estimating the quality of seed progeny in pine and when pine is used as a test object in cytogenetic monitoring. The limits of variation and the spectra of cytogenetic characteristics allowing the pine populations to maintain their homeostasis were also determined.  相似文献   

4.
Nei's genetic distances (Nei, 1972, 1978) between 12 Scotch pine (Pinus sylvestris L.) populations were determined using isozyme analysis. The gradients of these distances along the 1500-km meridional transect in the Transural Region and Northern Turgai from the pre-forest-tundra subzone (the Synya River basin) to the southern steppe (the Naurzumskii forest) were calculated. We discovered that the genetic distance gradients (GDGs) progressively increase in the direction from the northern boundary of the range to the southern boundary of the forest-steppe zone and sharply increase in the insular forests growing in the steppe zone. The results of cluster analysis and Mahalanobis distance gradients with respect to a set of morphological characters of the cones provide evidence that Scotch pine populations of the forest zone share somewhat the same gene pool, whereas the group of Scotch pine populations in the insular forests of Northern Turgai is obviously differentiated phenogenetically from the insular forests of the Tobol region, which grow farther to the north.  相似文献   

5.
Results of a comparative analysis of the frequency and spectrum of cytogenetic anomalies are presented for reproductive (seeds) and vegetative (needles) samples taken from Scotch pine (Pinus sylvestris, L.) micropopulations growing at sites with differing levels of radioactive contamination in the Chernobyl NPP 30 km zone, and at the location of a facility for the processing and storage of radioactive wastes (the 'Radon' LWPE, near the town of Sosnovy Bor in the Leningrad Region). The data obtained indicate the presence of genotoxic contaminants in the environment of the tree micropopulations. Chemical toxins make the main contribution to the environmental contamination in the Sosnovy Bor area as compared with the influence of ionising radiation in the Chernobyl 30 km zone. The higher radioresistance of seeds of Scotch pine growing on the area of the 'Radon' LWPE and in the centre of Sosnovy Bor town was revealed with acute gamma-radiation.  相似文献   

6.
The spectrum and frequency of cytogenetic aberrations in the reproductive (seeds) and vegetative (foliage) organs of Scotch pine (Pinus sylvestris L.) have been studied in the vicinity of the LSK Radon facility for radioactive waste storage and processing and in a 30-km zone around the Chernobyl Nuclear Power Plant. The results indicate that the pine populations of these regions are exposed to mutagenic factors. In contrast to the 30-km Chernobyl zone, the increased environmental mutagenicity in the vicinity of LSK Radon and in the center of the city of Sosnovyi Bor is mainly accounted for by chemical factors. The results of additional acute γ-irradiation have shown an increased radiation resistance of Scotch pine seeds from the LSK Radon and Sosnovyi Bor populations. Regression analysis demonstrated a significant increase in the cytogenetic aberration rate in plants from the experimental plots throughout the study period (1997–2002).__________Translated from Ekologiya, No. 4, 2005, pp. 275–285.Original Russian Text Copyright © 2005 by Geras’kin, Vasil’ev, Dikarev, Udalova, Evseeva, Dikareva, Zimin.  相似文献   

7.
Characteristics of the adaptive response of the female generative system of Scotch pine to air pollution caused by petroleum gas burning in flares during oil production in Western Siberia have been studied. The relationship between the individual and endogenous variations of the quantitative parameters of pine cone morphology has been analyzed in different zones of deterioration.  相似文献   

8.
The methods of identification and scaling of phenes of forest plants are described. The phene identification consists of five stages. Specific features of studies at each stage are shown using identification of the phenes of seed color, cone color, and seed scale structure in Scotch pine (Pinus sylvestrisL.) as examples. The method of phene scaling is based on the comparison of phene frequencies in a bog and in adjacent upland populations of pine. At the boundary between the bog and dry land, the frequencies of population-level phenes change, whereas those of superpopulation-level phenes remain unchanged.  相似文献   

9.
The distribution of fine conducting roots of Siberian spruce, Siberian fir, and Scotch pine over the soil profile was studied in the taiga ecosystems polluted with heavy metals and SO2. Under conditions of heavy pollution, tree roots were not found in the forest litter. Regardless of the level of technogenic load, the largest amount of conducting roots concentrated in the upper layer of mineral soil.  相似文献   

10.
根根据长江荆江段沿江牛轭湖天鹅洲和尺八沉积钻孔柱样,在建立了高分辨率的年代框架的基础上,分别进行了沉积物孢粉、炭屑分析,并结合荆州市1955~2012年的气候数据、史志记载的洪水和火灾等环境事件进行了综合分析。结果显示:天鹅洲、尺八两湖泊钻孔沉积物的孢粉和炭屑特征均较好地响应了近百年来湖区周边的环境变化;牛轭湖在裁断成湖之前、成湖之后的孢粉、炭屑特征不同:成湖之前,沉积物总孢粉浓度与乔木、灌木孢粉浓度都相对较低,水生植物和蕨类植物孢粉浓度相对较高,成湖之后乔木孢粉浓度仍呈减小趋势,但灌木、水生植物孢粉浓度呈波动增加趋势;利用沉积物炭屑浓度与孢粉浓度的比值(C/P值)指标,可以较好地指示自然山火与人类聚居地火灾等燃烧事件在沉积物中的记录,而且综合利用C/P值与沉积物孢粉特征,有可能厘清长江全流域洪水与局地洪涝事件的沉积记录。  相似文献   

11.
Gradients of genetic distances (GGDs) between 26 adjacent cenopopulations of Scotch pine (Pinus sylvestris L.) along the transects through the distinct landscape-ecotopic isolation borders were analyzed graphically. The results made it possible to reveal and quantitatively estimate gradients and borders of gene-pool structural patterns in populations of this species in the central part of Northern Eurasia. In lowland areas, the most distinct borders were found between pine populations growing on dry lands and bogs (Pineta sphagnosa) in the forest zone of the Transural region, as well as between the Arakaragaiskii and Amankaragaiskii island pine forests in the steppe zone (Northern Turgai). In highland areas (the Urals and the Carpathians), the greatest GGDs were observed between low-mountain (about 600 m above sea level) and middle-mountain (850–900 m) populations. Analysis of GGDs is a promising gene-geographic method for determining population borders and studying the chorogenetic structure of species.  相似文献   

12.
A comparative analysis of field observations and experiments on the distance and rate of dispersal of self-sown Scotch pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) progeny has shown that the rate of their hydrochorous dissemination downstream is an order of magnitude higher than the rate of dispersal in upland areas. A hypothesis assigning priority to the role of hydrochory in the expansion of conifer populations to the tundra (periglacial) zone along with climate warming has been formulated and substantiated by comparative isozyme analysis of populations in transects lying along and across rivers.  相似文献   

13.
Fungal canker caused by Biatorella difformis [Fr.] Rehm. has a deleterious effect on the productivity of Scots pine. Affected trees are characterized by decreased biometric parameters of shoots and needles and impaired pollen germination and tube growth. Their pollen has reduced contents of reserve nutrients and physiologically active substances.  相似文献   

14.
The Holocene evolution of vegetation in the high-plain territory of the northwestern Volga Upland has been shown to have certain specific features. Based on analysis of spore–pollen assemblages from peat deposits, the onset of bog formation has been dated to the late Boreal period (about 8500 yr BP); the pine–birch phase in the development of forests, to the early Atlantic period (8000?6000 yr BP); the appearance and peak development of the zonal broadleaf species complex, to the late Atlantic period (6000?4500 yr BP); and early anthropogenic changes in the vegetation, to about 3000 yr BP.  相似文献   

15.
The results of gradient analysis of band pine forests in the Minusinsk Depression are presented. Methods of DCA ordination and correlation analysis have been used to reveal specific features of phytocenotic diversity formation in forest communities growing in azonal habitats of this steppe depression and to test zonal and typological forest units for ecological integrity. The role of directly acting zonal and compensatory ecological factors and specific relationships between types of forest communities and ecological-topographic conditions in the main forms of relief are considered.  相似文献   

16.
Abstract–Pollen of 42 plant species from 17 families has been found in the food stores of Seladonia subaurata nests, with 61–86% of the pollen being accounted for by the Compositae. The foragers are characterized by strict flower preferences: more than 90% of the pollen in each cell belongs to two or three, sometimes four, plant species. At the eusocial stage of the existence of a colony, two or three foragers usually provision each cell. In especially large colonies, foragers are divided into groups and provision several cells during the day.  相似文献   

17.
Morphophysiological parameters of needles have been studied in Scots pine (Pinus sylvestris L.) and Siberian spruce (Picea obovata Ledeb.) trees of different life states growing under conditions of industrial air pollution with sulfur and heavy metals. Three functional clusters (tentatively named the initial, transitional, and disastrous clusters), each characterized by a certain metabolic status, have been revealed, and their quantitative and qualitative structure has been evaluated. The morphophysiological responses of pine and spruce are shown to be qualitatively different, depending on differentiation of trees with respect to vitality under conditions of industrial pollution. Probable factors accounting for these differences are discussed.  相似文献   

18.
Long-term observations on needle transpiration in pine and spruce, the main forest-forming tree species in the North, made it possible to estimate the rate of this process depending on different ecological factors in years with different weather conditions. Using a large amount of data, an attempt was made to compare transpiration rates in pine and spruce and reveal some specific features of this process under conditions of the North.  相似文献   

19.
Chronologies of the anatomical and integral parameters of the Scots pine (Pinus sylvestris L.) earlywood and latewood were investigated for two sites in the Minusinsk depression with different soil moisture conditions. Patterns of statistical characteristics and climatic responses of the chronologies were identified. Differences between sites were revealed in the cell diameter and wall thickness distributions. These differences are indicators of adapting pine wood structure to the moisture deficit.  相似文献   

20.
Morphological parameters of the root system (the length of conducting roots and the number of absorbing roots) and the rate of its mycorrhization have been studied in one-year Scots pine seedlings from burned-out areas of cowberry-herb-green moss pine forest in the northern forest-steppe subzone of Western Siberia. The results show that the length of conducting roots in such seedlings increases, whereas the rate and density of mycorrhiza formation in absorbing roots decrease, compared to those in plants from unburned areas. The structure of underground organs in pine seedlings depends not only on fire intensity but also on the type of substrate in the burned-out area.  相似文献   

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