176 research outputs found

    Edge Effect: Growth and Morphogenetic Features of Scots Pine Trees in Forest Parks and Natural Stands

    Get PDF
    The degree of development and depth of edge effect are studied in some fragments of forest-park stands under long-term urbanization impact (in the city of Yekaterinburg, Russia) and in natural forests using the method of transect investigation. The method of quantitative assessment of tree stem and crown growth features by a set of morphological characteristics was used. The objects of the research included the edges of Scots pine stands. The edge effect was determined by two of the five studied characteristics: foliation and branchiness, which characterize the level of the development of the tree assimilation apparatus. The general trends indicate an increase in the development of these characters in natural stands and decrease in the forest park at increased distance from the edge. The nonlinear development of morphological characteristics along the transects is due to different types of tree responses on the impact of determining morphogenesis factors. Four statistically significant different zones were identified in the natural stands at distances of 0-75, 100-125, 150-175, and 200-225 m from the forest edge and only two zones were differentiated in the forest park. The unified approach to data analysis suggests the edge effect in both habitats at a distance of 75-100 m from the forest edge according to branchiness and 100-125 m according to foliation. Several types of morphogenetic tree responses, distinguished by the degree of foliation and branchiness variation under edge effect impact, are revealed.This study was supported by the Integrated Program of the Ural Branch of the Russian Academy of Sciences for 2018-2020 (grant no. 18-4-4-10) and performed under the State Assignment of the Botanical Garden, Ural Branch, Russian Academy of Sciences

    Dynamics of Branch and Stem Apical Growth in the Progenies of Plus Pine Trees (Pinus sylvestris L.)

    Get PDF
    The relationship between the characteristics of the linear growth of branches and stems was studied, as well as the possibility of distinguishing between various Scots pine (Pinus sylvestris L.) genotypes. The objects of research were experimental plantations of the half-sib progenies of pine plus trees aged 10–11 years. The annual increments of the stem and differently oriented branches were measured. Correlation, regression and data analysis methods developed by the authors were used. The time dynamics of the obtained values were studied by comparing the regression line slopes describing the interrelation of axial increments and by analysis of the frequency spectra of the Integral Parameter of Characters Sequence applied earlier. The analysisof the obtained results has shown the existence of a significant relationship between auxiblast linear growth within the two adjacent years and a weak interrelation of the characteristics of branch and stem morphogenesis. The possibility of distinguishing Scots pine half-sib families by comparing the dynamics of branches and stem apical growth is described. Keywords: Scots pine, apical growth of branches and stems, genotypic and phenotypic variability, impact of environmental factors on growth, morphogenesis of woody plants, growth modelin

    On the superfluidity of classical liquid in nanotubes

    Full text link
    In 2001, the author proposed the ultra second quantization method. The ultra second quantization of the Schr\"odinger equation, as well as its ordinary second quantization, is a representation of the N-particle Schr\"odinger equation, and this means that basically the ultra second quantization of the equation is the same as the original N-particle equation: they coincide in 3N-dimensional space. We consider a short action pairwise potential V(x_i -x_j). This means that as the number of particles tends to infinity, NN\to\infty, interaction is possible for only a finite number of particles. Therefore, the potential depends on N in the following way: VN=V((xixj)N1/3)V_N=V((x_i-x_j)N^{1/3}). If V(y) is finite with support ΩV\Omega_V, then as NN\to\infty the support engulfs a finite number of particles, and this number does not depend on N. As a result, it turns out that the superfluidity occurs for velocities less than min(λcrit,h2mR)\min(\lambda_{\text{crit}}, \frac{h}{2mR}), where λcrit\lambda_{\text{crit}} is the critical Landau velocity and R is the radius of the nanotube.Comment: Latex, 20p. The text is presented for the International Workshop "Idempotent and tropical mathematics and problems of mathematical physics", Independent University of Moscow, Moscow, August 25--30, 2007 and to be published in the Russian Journal of Mathematical Physics, 2007, vol. 15, #

    Seasonal changes in chlorophyll and carotenoid content in needles of scots pines (pinus sylvestris l.) Exposed to the thermal field of a gas flare

    Get PDF
    Seasonal changes in chlorophyll (Chl) and carotenoid (Car) content were analyzed in needle samples from young Scots pines (Pinus sylvestris L.) growing in the thermal field zone at various distances from the petroleum gas flare. Experiments were performed in Khanty Mansi Autonomous Area (Yugra) of Russia throughout the autumn–winter–spring period. Two hypotheses were subject to verification: (1) the thermal field of petroleum gas combustion flame imitates the influence of climate warming on plants, thus affecting the pigment complex of the photosynthetic apparatus (PSA) in pine needles; (2) transformations of PSA pigment complex in pine needles throughout the autumn–winter–spring period are sensitive to a long-term rise in ambient temperature by 1–2°С. In the winter period, the seasonal dynamics of certain PSA parameters comprised maxima and minima that are supposedly due to the regulation of Chl and Car content upon changes in air temperature. In trees growing under divergent thermal conditions, seasonal changes of these parameters were not synchronous. Analysis of seasonal changes revealed that winter-related transformations of the PSA structural–functional condition in needles are subject to consistent variations at different distances from the gas flame. The PSA activity of needles throughout the studied period was higher near the flame and decreased with the distance from the gas flare. When Chl content in needles decreased in autumn–winter, the smallest reduction was observed in the location near the gas flare (site I) where temperature was 1–2°C higher than the background level. The intermediate decrease in pigment content was noted at a moderate distance from the flame (site III), while the most pronounced decrease occurred at the largest distance from the gas flare (site VII). At the same time, the Chl a/b content ratio in needles was consistently lower for trees located at site I than at site VII. Hence, the amount of light-harvesting complexes in chloroplasts from trees grown at site I was higher than the amount of photosystems in the same chloroplasts. The Chl (a + b)/Car ratio in needles of trees grown near the gas flare (site I) was higher than in locations III and VII. This ratio displayed two significant peaks in the winter dynamics, which was supposedly due to the sufficient preservation of green pigments. Divergent seasonal changes in Chl and Car content and their dissimilar correlations with air temperature indicate that the pools of these pigments are controlled by different mechanisms. The actual Chl content, determined by the balance of pigment degradation and synthesis, should depend on the environmentally modified Chl synthesis and on the protective function of Car. Photosynthesizing cells produce additional amounts of carotenoids during autumn–winter, thus preventing the photodegradation of Chl in the period from autumn to late spring. © 2021, Pleiades Publishing, Ltd.This work was supported by the Comprehensive Program of the Ural Branch of the Russian Academy of Sciences for 2018–2020 (project no. 18-4-4-10) and by a state assignment to the Institute Botanic Garden of the Ural Branch of the Russian Academy of Sciences

    Diversity of hard-bottom fauna relative to environmental gradients in Kongsfjorden, Svalbard

    Get PDF
    A baseline study of hard-bottom zoobenthos in relation to environmental gradients in Kongsfjorden, a glacial fjord in Svalbard, is presented, based on collections from 1996 to 1998. The total species richness in 62 samples from 0 to 30 m depth along five transects was 403 species. Because 32 taxa could not be identified to species level and because 11 species are probably new to science, the total number of identified species was 360. Of these, 47 species are new for Svalbard waters. Bryozoa was the most diverse group. Biogeographic composition revealed features of both Arctic and sub-Arctic properties of the fauna. Species richness, frequency of species occurrence, mean abundance and biomass generally decreased towards the tidal glaciers in inner Kongsfjorden. Among eight environmental factors, depth was most important for explaining variance in the composition of the zoobenthos. The diversity was consistently low at shallow depths, whereas the non-linear patterns of species composition of deeper samples indicated a transitional zone between surface and deeper water masses at 15–20 m depth. Groups of “colonial” and “non-colonial” species differed in diversity, biogeographic composition and distribution by location and depth as well as in relation to other environmental factors. “Non-colonial” species made a greater contribution than “colonial” species to total species richness, total occurrence and biomass in samples, and were more influenced by the depth gradient. Biogeographic composition was sensitive to variation of zoobenthic characteristics over the studied depth range. A list of recorded species and a description of sampling sites are presented

    Seasonal Dynamics of Content of Antioxidant System Component in Needles of Scots Pine (Pinus sylvestris L.) Trees Situated in the Local Warming Impact Zone

    Get PDF
    The seasonal changes in a period of low temperatures and characteristic correlations of some antioxidant system (AOS) components in pine needles influenced by a gas flare are investigated in this study. The parameters taken are total water content (TWC) in needles, peroxidase activity (AP) and selected elements of the antioxidant system of needles, such as content of carotenoids (Car), ascorbic acid (AA), catechins (Cat) and flavanols (Fl). The needles come from Scots pine trees (Pinus sylvestris L.), which grow in a gradient of environmental conditions formed in the zone of thermal field of the gas flare impact (at various distances). The gas flare is situated on the territory of the Khanty-Mansiysk Autonomous Okrug (UGRA) of Russia. Three hypotheses were subject to verification: 1) the thermal field of the gas flare during the low temperature period affects the water exchange and the AOS state of needles; 2) increase in temperature of the environment in the flare impact zone during the autumn-winter period causes the decrease in amount of moisture in needles, which is a trait of oxidative stress in cells; 3) in the functioning of a needle's AOS, there are correlations between its components, which values depend on distance from the gas flare and environment created by it. It was found that in the thermal field gradient of the flare, there is neither an additional reduction in TWC in needles compared to the background nor signs of change in the state of AOS corresponding to the oxidative stress in the cells. The greatest impact of the gas flare on characteristics of the physiological state of pine needles is observed in the section closest to the flare. It reveals in the higher values of AP, TWC, Car and decrease in concentration of Fl and AA. The seasonal dynamics of the studied traits values do not correlate with the temperature of the environment. It indicates the indirect effect on the regulation of needle's AOS activity. The factor and correlation analysis of the data indicate a difference in physiological state of pine needles at different distances from the flare. There is no domination of any processes in the functioning of AOS components. The observed correlations between the studied properties change according to distance to the flare. The most stable is a negative AP relationship with ofter parameters, which rise with the increased distance from the flare. The consistency degree of separate AOS components functioning is maximal in background conditions and decreases when approaching the flare. This fact is explained by the modifying effect of the flare on physiological and biochemical processes of the needle's adaptation to specific climatic conditions of the environment.Исследовали сезонные изменения в период низких температур и характер корреляционных связей для содержания общей воды в хвое, пероксидазной активности и содержания отдельных компонентов антиокислительной системы хвои: каротиноидов, аскорбиновой кислоты, катехинов и флавонолов – у деревьев сосны обыкновенной (Pinus sylvestris L.), произрастающих в градиенте условий среды, формируемых в зоне влияния теплового поля газового факела (на разном удалении от него) на территории Ханты-Мансийского автономного округа – Югры (Россия). Проверены 3 гипотезы: 1) тепловое поле газового факела в условиях низких температур влияет на водный обмен и состояние антиокислительной системы хвои; 2) повышение температуры среды в зоне влияния факела в осенне-зимний период приводит к уменьшению количества влаги в хвое, которое вызывает состояние окислительного стресса в клетках; 3) в работе антиокислительной системы хвои между ее отдельными компонентами существуют взаимосвязи, характеристики которых трансформируются в зависимости от условий среды, определяемых удалением от газового факела. В градиенте действия теплового поля факела не наблюдается дополнительного по сравнению с фоном снижения содержания общей воды в хвое и признаков изменения состояния антиокислительной системы, характерных для окислительного стресса. Влияние газового факела на показатели физиологического состояния хвои максимально на ближней к факелу секции. Оно проявляется в виде увеличения пероксидазной активности, количества общей воды, каротиноидов и в снижении содержания флавоноидов и аскорбиновой кислоты. Сезонная динамика изученных показателей не коррелирует с температурой среды, что говорит о ее непрямом действии на регуляцию активности антиокислительной системы хвои. Факторный и корреляционный анализ данных свидетельствуют об отличии физиологического состояния хвои на разном удалении от факела. В функционировании компо- нентов антиокислительной системы хвои не наблюдается доминирования отдельных процессов. Взаимосвязи между изученными показателями изменяются с удалением от факела. Наиболее устойчивой является отрицательная связь пероксидазной активно- сти с остальными показателями, усиливающаяся с увеличением расстояния до факела. Степень согласованности работы отдельных компонентов антиокислительной системы максимальна в условиях фона и уменьшается с приближением к факелу. Это объясняется модифицирующим влиянием факела на физиолого-биохимическиеThis work was financially supported by the Comprehensive Program of the Ural Branch of the Russian Academy of Sciences for 2018-2020 (Grant No. 18-4-4-10) and within the state assignment of the Federal State Budgetary Institution of Science ?Institute Botanic Garden of the Ural Branch of the Russian Academy of Sciences?

    Ecoregional Analysis of Nearshore Sea-Surface Temperature in the North Pacific

    Get PDF
    The quantification and description of sea surface temperature (SST) is critically important because it can influence the distribution, migration, and invasion of marine species; furthermore, SSTs are expected to be affected by climate change. To better understand present temperature regimes, we assembled a 29-year nearshore time series of mean monthly SSTs along the North Pacific coastline using remotely-sensed satellite data collected with the Advanced Very High Resolution Radiometer (AVHRR) instrument. We then used the dataset to describe nearshore (<20 km offshore) SST patterns of 16 North Pacific ecoregions delineated by the Marine Ecoregions of the World (MEOW) hierarchical schema. Annual mean temperature varied from 3.8°C along the Kamchatka ecoregion to 24.8°C in the Cortezian ecoregion. There are smaller annual ranges and less variability in SST in the Northeast Pacific relative to the Northwest Pacific. Within the 16 ecoregions, 31–94% of the variance in SST is explained by the annual cycle, with the annual cycle explaining the least variation in the Northern California ecoregion and the most variation in the Yellow Sea ecoregion. Clustering on mean monthly SSTs of each ecoregion showed a clear break between the ecoregions within the Warm and Cold Temperate provinces of the MEOW schema, though several of the ecoregions contained within the provinces did not show a significant difference in mean seasonal temperature patterns. Comparison of these temperature patterns shared some similarities and differences with previous biogeographic classifications and the Large Marine Ecosystems (LMEs). Finally, we provide a web link to the processed data for use by other researchers

    Biodiversity Trends along the Western European Margin

    Get PDF
    corecore