Populations of Agrostis diluta Kurcz. and Psathyrostachys caespitosa (Sukaczev) Peschkova in Yakutia: dynamics of vitality

In Yakutia, natural floodplain meadows and steppes have long been involved in economic activities. To develop methods of rational use, one needs to constantly consider the state of vegetation, mainly its constituent populations. Our research focuses on studying the dynamics of the vitality of the populations of the Agrostis diluta Kurcz. and steppe Psathyrostachys caespitosa (Sukaczev) Peschkova cereals. These species play an essential role in the composition of vegetation cover. We determined the vitality coefficient IVC. Our study of populations over several years has revealed the dynamic mobility of the vital structure, which is of adaptive significance and ensures the sustainability of populations. We have found that the vital structure of the cereal populations of the meadow Agrostis diluta and the steppe Psathyrostachys caespitosa during long-term studies (2007–2013 and 2007–2016, respectively) is heterogeneous. In unfavorable humidification conditions, we characterize years as depressive. Under favorable conditions of humidification, they quickly turn into thriving plants. In addition to the weather of the vegetation periods, habitat specificity affects the vitality of species populations that differ in ecological and coenotic characteristics. The Q quality index and IVC correspond to each other by year and form a clear descending order during the transition from a thriving to a depressive state. Currently, the vital state of the populations of both species is satisfactory.

Highly Productive Pine Forests in a Changing Climate

Forest steppe of the Central Chernozem Region (CCR) of Russia belongs to the zone of highly productive pine forests. In 2015, for the first time a partial destabilization of Scots pine (Pinus sylvestris L.) was recorded within the territory of the CCR. It affected the population, organism and cellular levels of Scots pine (Pinus sylvestris L.). The destabilization was caused by the 8-year heatwave of 2007–2014 followed by a sharp drop in the water table and four severe droughts (2007, 2010, 2012, and 2014). The analysis was carried out on two sites of pine forest plantations growing in the environmentally sound region: the Stupino test site (Voronezh region, typical plantation for the CCR) and the Usman site (Lipetsk region, lands with elevated groundwater level). The results of morphological, cytogenetic and biochemical studies of model trees of the Stupino test site during the following periods are presented: 4 optimal years in terms of weather conditions, 2014 drought year and 2015 destabilization year. It was found that prolonged hydrothermal stress resulted in the transition of pine from the basic equilibrium state to a slightly nonequilibrium state. The trigger mechanism for changing their vital state was a severe autumn soil drought in 2014, after which the plants became weakened right before winter. A decrease in cone bioproductivity by the traits of seed fullness and the total number of seeds per cone, a change in population sampling structure, an increase in the number of mitosis pathologies, and an increase in proline content in needles were observed despite optimal weather conditions in 2015. The recovery of species was studied for three subsequent optimal years on the example of the Stupino and Usman populations. Experimental data indicate that the processes of vital state normalization involve profound changes in metabolism and require certain energy expenditures. It took the Stupino population longer to return to the regional norm, which indicates a different depth of destabilization of the tree genetic material of the studied populations. For citation: Kuznetsova N.F., Klushevskaya E.S, Amineva E.Yu. Highly Productive Pine Forests in a Changing Climate. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 6, pp. 9–23. DOI: 10.37482/0536-1036-2021-6-9-23

Ecological and biological features of silver birch (Betula pendula) in the conditions of an industrial city

The article provides data on phenology, on the content of ascorbic acid in Betula pendula Roth., growing in the conditions of the industrial city of Naberezhnye Chelny in the Republic of Tatarstan, which is a region of the Russian Federation. It is noted that natural phytocenoses are characterized by lower air temperatures in comparison with plantations of sanitary protection zones of industrial enterprises and highway plantings. According to phenological data, in urban plantings, there was observed an increase in defects, a decrease in the vital state, which is associated with severe damage to leaf blades, the formation of leaf necrosis, a decrease in the living area of leaves, which is a consequence of an intense technogenic load on woody plants. It was revealed that the content of ascorbic acid in birch leaves depends on the vegetation stage.

The influence of edaphic factors on the vital state of large-flowered magnolia (Magnolia grandiflora L.). in the Nikitsky Botanical Gardens

The most widespread magnolia on the Southern coast of the Crimea and, in particular, in the Arboretum of the Nikitsky Botanical Gardens is the evergreen Magnolia grandiflora L., introduced in 1817. Currently, 28 generative specimens of Magnolia grandiflora of different ages grow in the Arboretum, including garden forms with different vital state. There are very few data on the relation of this species to soil conditions. For this reason, we have studied the influence of edaphic factors on the vital state of Magnolia grandiflora growing in the Arboretum of the Nikitsky Botanical Gardens. A number of limiting edaphic factors have been identified, the main of which is the high skeletal structure of the soil. The humus reserves in the soil have a positive effect on the vital state of trees. A high level of agricultural technology is the main method of improving the vital state of Magnolia grandiflora .

State of woody vegetation in an urbanized environment (the example of Krasnoyarsk)

Woody plants are one of the effective ways of stabilising the ecological environment of large industrial cities. In order to maximize the effect of green spaces a large and diverse research effort is needed to study the urban green spaces, assess their ecological plasticity and adaptive potential. The results of such research will be the basis for recommendations on the selection of an assortment of species for landscaping of urban areas. The aim of the study was to investigate the condition of woody plants growing in the urban environment of Krasnoyarsk. Within the framework of the study a comprehensive assessment of existing urban green spaces was carried out for the first time for Krasnoyarsk. The species composition and age structure of plantings are established by the results of inventory of public plantings. The vital state of dominant species has been evaluated and their ecological and physiological characteristics, including the study of water retaining capacity of leaves, has been carried out. That allowed to estimate the impact of anthropogenic environment on the condition of urban woody plants.

Assessment of the volume of harvested wood in accordance with the vital state of wood species

During selective felling on the territory of 3.9 ha, 181 m3 of wood, 35% of which is dead wood. Among them, pine (16 m3), spruce (27 m3), birch (8 m3) and aspen (12 m3) were found. The volume of cut viable wood was 118 m3, including 50 m3 of pine, 44 m3 of spruce, 14m 3 of birch and 10 m3 of aspen. The values obtained do not exceed the forest declaration data. To determine the stumps from dead coniferous trees, the following criteria were tested: complete or partial absence of bark, the presence of traces of the vital activity of insect pests and abundance worm dust. Species-specific criteria are proposed: in pine – the presence of rot of the peripheral part of the wood, brown color of sapwood and bast; spruce – the presence of heart rot and wood destroying fungi. In deciduous species, the main criterion for isolating stumps from dead trees has been tested – the presence of wood-destroying fungi, in aspen – heart rot caused by tinder fungi. We recommend using these criteria to resolve legal claims against forest users in the removal and assessment of harvested wood.

Ecological and biological aspects of assessing woody plants in the landscaping of Novosibirsk

The ecological and biological characteristics of woody plants growing in the most popular squares of the Novosibirsk city (Teatralny, Pervomaisky, and Slavy square) have been investigated. 73 species of woody plants have been recorded. 13 of them are common to three landscape objects. Ornamental garden forms of woody plants are found separately (13 intraspecific forms, hybrids and varieties of woody plants). Some species of molded plants that are not suitable for landscaping public urban space due to their low winter hardiness were recorded. The greatest species diversity is distinguished by the green spaces of the Slavy square. The correlation between the place of growth and the vital state of plants has not been found. Plants on the objects are in satisfactory vital condition. Species in an unsatisfactory condition are found singly. Shrubs (49% of the total) and trees of the first and second sizes (32%) predominate in terms of life forms. The plantations contain species of natural flora of the Novosibirsk region and introduced plants from other geographic regions (27 and 73%, respectively). Among the introduced plants, species with a wide Eurasian type of area prevail. Analysis of the history of the creation and reconstruction of landscape objects showed that the assortment of plants on the territory of Pervomaisky Square has changed to a greater extent, the species composition of plants in the Teatralny Square has changed insignificantly. To form a better spatial structure of landscape objects, we recommend to increase the species and form diversity of plantings by introduction of plants of various life forms and species that have passed introductory tests in local climatic conditions. This will provide the creation of landscapes and landscape compositions of various expressiveness and to form a comfortable environment for the rest of the citizens.

Picea obovata Ledeb. wood biochemical characteristics as state of plants

The process of forest destruction is very dynamic and covers the entire boreal zone of the Northern hemisphere. Against the background of deterioration of the sanitary condition of plantings, pathogenic organisms are activated. The article presents materials on the study of the chemical composition of wood of individuals of different life States of Pícea obovata Ledeb. In the context of IPS typographus L. distribution It is suggested that there is a difference in the chemical structure of wood in individuals of Siberian spruce in places of mass drying, which affects the population of pests. Plants of various life States were studied for the content of water-soluble, resin-like extractives and tannins. The obtained data were subjected to statistical processing. The results of the research revealed that the overall content of extractive substances is influenced by the vital state of individuals and growing conditions. It was found that with the deterioration of the plant condition, there is an increase in extractive substances. The overall increase in extractive substances occurs due to an increase in the group of water-soluble substances, namely tannins. The highest content of all groups of metabolites (including tannins) was observed in individuals of a satisfactory life condition.

Analysis of street plantations vitality after the rejuvenation pruning (on the example of Dnipro city)

The influence of pruning of the crown on the state of five tree species has been studied (Robinia pseudoacacia L., Ulmus pumila L., Gleditsia triacanthos L., Acer pseudoplatanus L. and Populus bolleana Lauch.). The trees were pruning at a height of 8 meters, leaving only the trunk and lower branches. Control plants were not pruned. All plants are growing on the boulevard near the highway with high traffic. It was found that among the rejuvenated trees there are more both healthy plants and severely damaged ones. Dead plants appeared among species such as G. triacanthos, A. pseudoplatanus, and R. pseudoacacia also. The best vital state was found in P. bolleana and U. pumila. Plants after crowning have more water content in leaves. U. pumila and G. triacanthos have the greatest difference in water content between the two variants. The intensity of transpiration in pruning plants P. bolleana and G. triacanthos is 2 times higher, and in U. pumila – by 20 %. In A. pseudoplatanus and R. pseudoacacia, there is no difference in this indicator between the variants. Pruned plants have a lower water-holding capacity by an average of 30 % compared to control (except for P. bolleana, in which the difference between the variants is insignificant). The content of green pigments is higher than in the control samples in the leaves of the rejuvenated plants. The exception is R. pseudoacacia, which has a reverse reaction. Thus, the intensification of the processes of water exchange and the pigment system does not occur in all species to the same extent. It is most pronounced in U. pumila and G. triacanthos. The activity of photosynthesis and water exchange in both variants differs insignificantly at P. bolleana. R. pseudoacacia have deterioration in all parameters. This probably explains the poor condition of pruned trees of this species.

ПЛАТАН КЛЕНОЛИСТИЙ (PLATANUS ACERIFOLIA WILLD.) В УМОВАХ МІСТ СТЕПОВОЇ ЗОНИ УКРАЇНИ

For steppe cities, it is important to replenish the range with durable decorative species that grow quickly and form a three-dimensional crown. Such plants due to the shading of large areas create more comfortable living conditions for people in steppe cities. These species include London planetree (Platanus acerifolia Willd.), which sporadically began to be planted in some cities in the postwar period. The viability of P. acerifolia in the steppe is different. Since the biological peculiarities of this introduced species have been studied in various socio-economic problems in cities, we conducted a comparative analysis of the vital state and biometric parameters of P. acerifolia in the plantations of two cities of the steppe zone of Ukraine. We found out that P. acerifolia is widely used in landscaping of Kherson, while in Kryvyi Rih it is rare. In Kherson, the species is distributed near administrative buildings, schools, hospitals; it grows in parks, squares and yards of high-rise buildings, and in Kryvyi Rih only in one subdistrict and in the arboretum of the Kryvyi Rih Botanical Garden. The trees in Kherson are aged 38–60. The vital state is estimated as high and close to high – 77.8–96.3%. Older trees are 18.4–21.5 m of height and a maximum trunk diameter is 80.1–99.4 cm. Plants of all plantations in Kherson have dry branches, with a rate of 6.3–28.7%. In Kryvyi Rih, 28–42-year-old trees grow. In different plantations of P. acerifolia, the number of dry branches varies in the range of 0.3–44.5%, and the vital state – from 55.5 to 100% depending on the place of growth. The height of P. acerifolia trees is 6.2–20.3 m, and the trunk diameter is 12.2–68.7 cm. The study has proved that the differences in vital state and morphometric parameters of trees in the plantations of these cities depend on the age of trees, their planting density, lighting and other growing conditions. Trees in Kryvyi Rih are more significantly damaged by cold winds than in Kherson. The life form of P. acerifolia in the plantations of Kherson and Kryvyi Rih is almost everywhere a single-stemmed tree. This species is beginning to naturalize in the conditions of Kherson. Several plants of self-seeding origin were found during the research studies. Restoration of plants with young sprouts produced by stumps after cutting the plant trunks in Kherson was also noticed. The leaf apparatus of plants during the growing season is practically not damaged by diseases and pests and no slimy stains are formed on the leaves. We determined that P. acerifolia is a promising species for wider use in landscaping of the cities of the Black Sea coast and settlements of the Right-Bank Steppe, but in the latter case requires successful selection of exhibition sites for successful growth. These, first of all, should be cozy places protected from the effects of cold winds in winter and dry winds in spring and summer.