Predominant Tree Species Research Articles

Interrelationships and Environmental Influences of Photosynthetic Capacity and Hydraulic Conductivity in Desert Species Populus pruinosa

An improved understanding of the mechanisms underlying plant adaptation to habitat heterogeneity can be achieved by clarifying the climate-driving factors of the hydraulic and photosynthetic traits of different populations. With a focus on Populus pruinosa Schrenk, which is the predominant tree species in the desert riparian forests of the Tarim Basin, Xinjiang, this study investigated the hydraulic and photosynthetic trait relationships and their interactions with environmental factors in 11 P. pruinosa populations using a Pearson correlation analysis, plant trait networks, a redundancy analysis, and a least squares linear regression analysis. The results showed that the degree of variation in the hydraulic traits was higher than that in the photosynthetic traits. The net photosynthetic rate (Pn) showed a significantly positive correlation with leaf-specific conductivity (Kl) and the Huber value (Hv). The Hv exhibited a significantly positive correlation with the water-use efficiency and Kl, and the branch–leaf mass ratio significantly affected the hydraulic traits. The groundwater depth (GD) in natural P. pruinosa forest habitats ranged from 3.4 to 7.9 m. With an increase in the annual average temperature, the hydraulic conductivity of the xylem significantly increased; with an increase in GD, Pn and Kl significantly decreased. The temperature annual range, temperature seasonality (standard deviation), min temperature of the coldest month, and GD were significantly correlated with the diameter and average path length of the overall trait network parameters, and these environmental factors affected the coordination of the functional traits of P. pruinosa.

Strategies and challenges of artificial forest reproduction in the forest-steppe zone: Experience of the Korsun-Shevchenkivskyi forest enterprise branch

One of the key problems that arise in the reproduction of forests in the paradigm of sustainable development of the forest industry is the volume of reforestation, which requires its correlation. This problem requires attention, since effective afforestation and reforestation determine the stability of the ecosystem and the importance of forest resources for the conservation of biodiversity in the forest sector. The purpose of the study is to investigate the features of artificial forest reproduction in the conditions of the forest-steppe climatic and geographical zone. The methodological basis for organising observations included field survey of planting material plots, monitoring the state of crops on the area, conducting analytical substantiation of progressive experience, and evaluating the final results obtained. The study was conducted in the Korsun-Shevchenkivskyi forest enterprise branch of the state enterprise “Forests of Ukraine”. The dynamics of annual volumes of artificial forest reproduction, considering the predominant tree species during 2012-2021, is presented. Additionally, the advantages and disadvantages of transplanting of main and related species in the presented forest conditions were analysed. During this period, there is a fluctuation in the volume of artificial forest reproduction in the forest districts under study. With regard to the transplanting of main and related species, it is worth noting its advantages in ensuring biodiversity and rapid forest regeneration. However, there are disadvantages, such as the possibility of losing genetic diversity and considering local conditions for effective seating. As a result, the study helped to determine the trends and features of forest reproduction in these forest districts, and to note the advantages and disadvantages of transplanting of the main and related breeds in various forest-growing conditions. The enterprise is actively implementing measures for forest reproduction, focusing on intensive planting of forest crops. This is achieved by placing plantations in areas that have been subjected to continuous sanitary and reforestation logging. One of the key tasks of the enterprise is to ensure high productivity of forest crops in the region. For this purpose, significant amounts of reforestation work are carried out, including systematic soil preparation and careful selection of optimal species for specific conditions. Considering the recommendations of forest management, an integrated approach to reforestation is reflected, which ensures sustainable and productive ecosystems in the region. The developed strategies can serve as an important tool for introducing innovations in the field of forestry

Features of the formation of the floodplain ecosystem of the black alder cluster in the conditions of the Orenburg Urals

The article provides original information on the peculiarities of the formation of a floodplain ecosystem with the predominant tree species Black Alder, a cluster type in the conditions of the steppe (treeless) Orenburg Urals. The object of study is located in a zone of extremely insufficient and unstable moisture in the floodplain area of the Ilek River during certain periods of the year. A bioecological assessment of the black alder plantation and its phenological features of development in the conditions of the arid steppe are given. Taxation characteristics of the stand allow us to give a qualitative assessment of the black alder cluster. Currently, on the territory of the Orenburg region there is no vector for the reproduction and promotion of natural regeneration of black alder, which is primarily due to the poor knowledge of the formed spatial ecotones. The identification of cluster plantings, which ontogenetically and phylogenetically demonstrate the ability to form stable natural, dynamically developing forest ecosystems, under the influence of anthropogenic load, has important scientific and practical significance.

Diversity, Ecology and Phytogeography of Bryophytes across Temperate Forest Communities-Insight from Mt. Papuk (Croatia, SE Europe).

It has been widely documented that the complex structure of forest ecosystems supports considerable bryophyte species and functional diversity. In this study, we assessed the diversity, distribution and ecological and phytogeographical features of bryophytes across a gradient of temperate forest types on Mt. Papuk. This is the largest and highest mountain in the lowland, Pannonian part of Croatia, with high geological diversity and various temperate forests covering 95% of the mountain. According to the predominant tree species (oak vs. beech), geological bedrock (calcareous vs. siliceous) and soil reaction (alkaline vs. acidic), 21 study plots were classified into four distinct forest types. In all, 184 bryophyte species (35 liverworts and 149 mosses) were recorded. Although the forest types investigated did not differ significantly with respect to species richness, each was characterized by a considerable number of diagnostic bryophyte species. According to our results, one of the main ecological factors determining the variability of the forest bryophyte composition was geological bedrock and the associated soil reaction. Basiphilous forests developed on carbonate bedrock harbored more thermophilous and nitrophilous bryophytes and were characterized by southern-temperate and Mediterranean-Atlantic biogeographic elements. In contrast, acidophilous forests growing on silicate bedrock were characterized by wide-boreal and boreo-arctic-montane elements, i.e., bryophytes indicating cooler habitats and nitrogen-deficient soils. Based on the results, we hypothesized that the main latitudinal biogeographic distinction between southern and northern biogeographic elements is driven more by geological substrate than by the main tree species in forest communities. The present study confirmed previous findings that bryophytes are good and specific habitat indicators and show associations with different forest types, which can help to understand the complexity, ecological microconditions and biogeographic characteristics of forest communities.

The effect of silvicultural systems on soil function depends on bedrock geology and altitude

Soil quality and function in forest environments are influenced by the interaction of soil-forming parameters and silvicultural systems. Hyrcanian forests were recently accepted as a UNESCO World Heritage Site, which extends across an area of approximately 1.8 million hectares and ascend to an elevation of 2800 m above sea level (m.a.s.l). In these woodlands, Oriental Beech (Fagus orientalis Lipsky) is the predominant tree species and could be observed at 700–1500 m.a.s.l., and occur on different parent rocks. Shelterwood and single-tree selection techniques have been the primary management methods for beech forests for the past forty years. Studies investigating the impacts of silvicultural systems have not yet been done on soil and forest floor features on different bedrock geology and altitudes. Therefore, in this study, we examined the influence of single-tree selection and shelterwood methods, 25 years after employing those methods, on soil quality and function compared to control areas (intact forests) in Hyrcanian beech stands. For this purpose, 15 forest floor (30 × 30 cm) and topsoil (0–10 cm depth) samples in each silvicultural systems (i.e., single-tree selection and shelterwood methods and control zones) × 4 regions (including Rasht, Nowshahr, Sari and Gorgan) × 4 altitude levels (with averages of 800, 1000, 1200 and 1400 m.a.s.l.) were considered. According to our findings, the investigated forest regions, forest floor and soil characteristics across various locations spots could be separated by principal component analysis output, and more than 85% of the variance was explained by the first and second axes. The structural equation model showed that the region, altitude and silvicultural systems had an effective role in the changes in soil biological activities by influencing the forest floor, and the soil physicochemical features. Based upon the network model, the C/N ratio, the sand content, the soil aggregate stability, the available K, the fulvic acid, and the Acarina density were found to be prominent factors with regard to soil function. In the control sites, increased soil organic material fractions, microbial/enzyme and biota activities were detected, particularly at the lower altitudes of the Nowshahr site, which had geological formations of dolomite and calcic layers. Taken together, it seems that the single-tree method, commonly referred to as the close-to-nature technique produces more suitable conditions for soil functioning compared to the shelterwood management approach. Silvicultural systems, bedrock geology and altitude can have major detrimental effects on soil function and fertility, over the long-term, impacts may increase with harvest intensity.

Maintaining the protective function of mountain forests under climate change by the concept of naturalness in tree species composition

In Swiss mountain areas, the protective function of forests is the predominant ecosystem service having high cultural and economic significance. It is assumed that natural forests or close-to-natural forests, i.e., forests being in the equilibrium with environmental conditions are the most resilient and resistant in regard to disturbances and hence best protecting people and assets on the long run. Here, we estimated the naturalness of the tree species composition by comparing Swiss National Forest Inventory (NFI) data with current and future potential Natural forest Site Types (NST). Based on this analysis, we identified species that are under or over-represented in protective mountain forests and derived the subsequent potential for management interventions. The urgency of management interventions is expected be small if all predominant tree species of the idealized potential natural forests are present and only their relative portions in the stand need adjustment. In contrast, interventions are advisable, if predominant tree species of the current and future potential natural forests are absent. Based on NFI data, the tree species composition of 47% of the protective mountain forests were classified as “natural” or “close-to-natural,” while the remaining 53% were classified as “not natural” or “partly natural.” Norway spruce [Picea abies (L.) H. Karst.] and European larch (Larix decidua Mill.) were the two most over-represented species under current and even more so under predicted future climatic conditions. To date, silver fir (Abies alba Mill.) and European beech (Fagus sylvatica L.) were the two species most frequently absent in protective mountain forests, in which they should prevail. Apart from European beech, the most prominent increase in prevalence is predicted for oak (sessile oak and pubescent oak; Quercus petrea Liebl., Q. pubescens Willd.) and small-leaved lime (Tilia cordata Mill.). These species were currently missing from more than 75% of the stands, in which they are expected to be dominant under future conditions. Our analysis indicates the need to transform tree species compositions of protective mountain forests to optimize fitness under future climates. Some of these transformations will take place naturally, incited by disturbances, others—the majority of them—will need active management interventions.

ASSESSMENT OF TREE SPECIES COMPOSITION AND DIVERSITY IN WASAJI FOREST RESERVE TARABA STATE, NIGERIA

The study was conducted in Wasasji Forest Reserve in Taraba State, Nigeria, it assessed tree species composition and diversity. Five transects of 1000m (1km) each were laid in the forest at an interval of 500m apart for the study. Sample plots of 50m x 50m sizes were laid in alternate positions along each transect at interval of 250m were used for data collection. In each sampled plot, tree species from ≥ 10cm diameter were identified and counted. These were used to determined the tree species composition, while their diversity indices were estimated using Shannon-wiener diversity index, margalef’s index (species richness index), species evenness, simpson’s diversity index and menhinick’s diversity index. The results revealed that a total of 48 different tree species comprising of 17 families were recorded in the forest. The family of moraceae had the highest (8) number of species representation in the forest. The most predominant tree species are Funtumia elastica, Tetrapleura tetraptera, Uapaca heudolitii, Ceiba pentandra and Erythrophleum suavolens. The Shannon-wiener index of (3.49), Species richness (7.56), species evenness (0.49), simpson’s index ( ), and menhinick’s (6.21) were estimated for the forest which are high. The state government should regulate cutting of trees in the forest.

Nesting sites of cavity nesting honey bees (Apis spp.) in natural ecosystems of Kerala, India

Natural colonies of cavity nesting honey bees are important for the conservation of bees. This study was aimed to determine the nesting habitat, nesting sites, nest height, and nest characteristics of naturally occurring cavity nesting honey bees in Kerala. The results showed that primary forests, disturbed or agricultural land as well as undisturbed lands were found to be the nesting habits of cavity nesting bees in Kerala. Among the nesting sites, tree hollows were the prevalent nesting sites of cavity nesting bees in Kerala wherein, the predominant tree species was Tectona grandis. The nest height of honey bee colonies from ground level varied from 0 cm to 600 cm and the number of combs in a colony varied from five to twelve. No significant differences were observed in the nest height and number of combs in the honey bee colonies in hill and plain regions of Kerala. Biserial correlation analysis revealed that in the plain regions, the proportion of parallel arrangement of combs to the direction of nest entrance was high (0.83) whereas in hilly regions the proportion of comb arrangement at right angles to the nest entrance was high (0.88).

A phytoindicational assessment of the vegetation of afforestation belts in the Middle Dnipro Region, Ukraine

Abstract We performed a study of the vegetation of afforestation belts in the Middle Dnipro Region of Ukraine. These were planted to protect agricultural land from adverse climatic conditions. The syntaxonomy of these afforestation belts is, so far, embedded in the synanthropic class of Robinietea tree plantations, but over time, these may need another syntaxonomic solution. Based on the data, a phytoindicational assessment of these communities was performed. The ecological features of the vegetation of afforestation belts have been determined by the mutual influence of ecological factors of different origin, and the extent of these impacts. In particular, the climatic conditions and edaphic factors and also the peculiarities of the environment-forming influence of different dominant tree species in the main layers and the age of these plantations, which determines at different stages of sylvestral succession processes. According to our phytoindicational assessment, use of cluster analysis of these biotopes of afforestation belts, proved their considerable similarity taking into account all ecological factors, and the distribution is mainly due to the predominant tree species. As a result of ordination analysis, it was found that the factors that most correlate with the ordinal axes are light regime, soil nitrogen and humidity. Phytocoenoses of afforestation belts are a very specific component of the forest biome in this region, because they have been artificially created.

Species-specific growth and transpiration response to changing environmental conditions in floodplain forest

Recent changes in the floodplain forests of Central Europe, caused mainly by changes in hydrological management and the increased frequency of droughts due to climate change, have led to severe degradation of floodplain ecosystems. Our main objective was to determine the sensitivity of trees to drought by observing the response of the tree phenology, stem radial growth, and physiology (sap flow) of three predominant tree species, namely English oak, narrow-leaved ash, and common hornbeam, to the environmental variables (climate). Stem radial growth began before bud break in ring-porous oak and ash, whereas in diffuse-porous hornbeam, growth onset occurred after leaf formation. The early onset with intense growth during favorable months (April–May) observed in ring-porous species was a major prerequisite for the successful growth of oak and ash at this site. Tree water deficit (TWD), an indicator of stem hydration, was triggered by decreasing soil moisture in all species, and was most prominent in ash, followed by oak. Intriguingly, sap flow was decoupled from TWD in all species and was driven primarily by evaporative demand from the atmosphere. Oak was the least conservative in regulating sap flow under atmospheric drought followed by hornbeam, whereas ash was most restricted and reduced its transpiration during dry periods. In contrast, ash was characterized by the highest radial growth and growth-based water-use efficiency. The lower water storage capacity of oak and ash is likely compensated by deep rooting and drought avoidance strategies, respectively. Tree species that tend to use surface soil water could be severely limited by more extractive species such as hornbeam. Despite the contrasting leaf and wood phenology, stomatal control, and rooting depth among the studied floodplain tree species, they exhibited analogous sap flow and water storage dynamics responses to drier conditions that enabled them to co-exist in the South Moravian Region. Nevertheless, our results suggest that the severe droughts and human-induced alterations in groundwater pose serious threats to floodplain forests in Central Europe, with certain tree species being unable to adapt to these altered conditions.

Indonesian urban forest policies, practice and bioenergy potential of urban forest tree species

ABSTRACT This study examines Indonesian urban forest policy, practice, and potential with reference to forest composition and bioenergy potential. The results showed that there are challenges in the implementation of urban forest policies into urban forest practices. For example, the land size allocation for urban forests in Jakarta, Surabaya, and Malang is still not in accordance with the existing policies as their land size is far less than 10% of these total areas. Predominant tree species in Indonesian urban forestry are Pterocarpus indicus, Delonix regia, Polyalthia longifolia, Lagerstroemia speciosa, Mimusops elengi, Samanea saman, Tectona grandis, Ficus benjamina, Mangifera indica, and Tamarindus indica. These trees are considered as multipurpose species that can be utilised for bioenergy, wood-based furniture, food and foraging, medicine, and many other uses. Aside from firewood and charcoal, these trees should be explored for their potential as biofuel, biogas, bio-pellet, and electricity generation. Bioenergy potential of urban forest trees can be an important consideration for the Government of Indonesia to actualise the potential of the urban forest and to create energy-independent cities.

Phylogeography Reveals Geographic and Environmental Factors Driving Genetic Differentiation of Populus sect. Turanga in Northwest China.

Populus sect. Turanga (hereafter referred to as “Populus”), including Populus euphratica and Populus pruinosa, are the predominant tree species in desert riparian forests in northwestern China. These trees play key roles in maintaining ecosystem balance, curbing desertification, and protecting biodiversity. However, the distribution area of Populus forests has been severely diminished and degraded in recent years due to increased habitat destruction and human activity. Understanding the genetic diversity among Populus individuals and populations is essential for designing conservation strategies, but comprehensive studies of their genetic diversity in northwest China are lacking. Here, we assessed the population structures and genetic diversity of 1,620 samples from 85 natural populations of Populus (59 P. euphratica and 26 P. pruinosa populations) covering all of northwestern China using 120 single nucleotide polymorphism (SNP) markers. Analysis of population structure revealed significant differentiation between these two sister species and indicated that strong geographical distribution patterns, a geographical barrier, and environmental heterogeneity shaped the extant genetic patterns of Populus. Both P. euphratica and P. pruinosa populations in southern Xinjiang had higher genetic diversity than populations in other clades, perhaps contributing to local geographic structure and strong gene flow. Analysis of molecular variance (AMOVA) identified 15% variance among and 85% variance within subpopulations. Mantel tests suggested that the genetic variation among P. euphratica and P. pruinosa populations could be explained by both geographical and environmental distance. The genetic diversity of P. euphratica showed a significant negative correlation with latitude and longitude and a positive correlation with various environmental factors, such as precipitation of warmest quarter and driest month, temperature seasonality, and annual mean temperature. These findings provide insights into how the genetic differentiation of endangered Populus species was driven by geographical and environmental factors, which should be helpful for designing strategies to protect these genetic resources in the future.

Tree Diversity, Stand Structure and Community Composition of Tropical Forest in Eastern Ghats of Tamil Nadu, India

rest of Eastern Ghats is degrading due to various anthropogenic pressures. In a present study to assess the tree diversity and population structure in the tropical forest of Javadhu hill Eastern Ghats, Tamil Nadu, India, total of 62 tree species belonging to 44 genera and 23 families and 5140 stems were enumerated in 10 ha plots. Memecylon umbellatum was the predominant tree species followed by Psydrax dicoccos, Chloroxylon swietenia and Anogeissus latifolia. The mean density was 514 stems ha -1 and the density of trees ranged from 469-623 ha -1 . The basal area in all the study plots ranged from 19.4 m 2 /ha to 33.2 m 2 /ha and the mean basal area for the 10 ha plots was 19.87 m 2 /ha. All top five species had greater density and basal area in 30-90 cm girth class. The Euphorbiaceae are taxonomically diverse and constituted the most-speciose family followed by Combretaceae. The species richness of deciduous species was greater followed by evergreen and brevi-deciduous. The present study reveals that the forest ecosystem restores considerable tree diversity here which is under more threat due to anthropogenic pressure. Therefore, immediate conservation measure is required to preserve the vanishing forest resources.

Contribution of biological soil crusts to soil organic matter composition and stability in temperate forests

Biological soil crusts (biocrusts) play an important role in the biogeochemical C-, N- and P-cycles but there is limited knowledge about their effect on the composition and stability of organic matter (OM) in soil. In pine and beech dominated temperate forests, the different compartments of biocrust, crust-adhering soil and crust-free soil were analysed by pyrolysis field ionization mass spectrometry (Py-FIMS) and C K-edge X-ray absorption near edge structure (XANES) spectroscopy. Phototrophic biocrust communities had been determined morphologically. Predominant tree species affected OM composition and stability but an overriding effect of biocrust organisms was observed. In biocrusts, the OM mineralization potential was high due to a high carbohydrate/ketone ratio and a high proportion of the fatty acid C22:0. A high proportion of free fatty acids in combination with a high carbohydrate proportion was identified as a relative marker for biocrusts and additional high proportions of lignin dimers were specific for samples under pine. In biocrust under pine, OM in soil compartments was characterized by large proportions of long-chain aliphatics from plant cuticular material. In A-horizon substrate under beech, OM compound classes were not affected by phototrophic species richness, suggesting functional redundancy of these biocrust organisms with regard to OM composition. In contrast to A-horizon substrate, OM in C-horizon substrate was characterized by a higher proportion of easily decomposable material. Under pine, forest management intensity (SMI) affected OM by stand age and density due to effects on phototrophic biocrust species. We conclude that compartment, vegetation, horizon substrate and SMI affected OM composition and stability, and biocrusts hence contributed to soil OM diversity in forest ecosystems.

Incidence and Severity of End-Splitting in Plantation-Grown Eucalyptus pellita F. Muell. in North Borneo

Eucalyptus pellita F. Muell. is currently the predominant tree species deployed for tree plantation establishment in some parts of Borneo, particularly Sabah state, Malaysia. Its low disease susceptibility, good growth and form, and desirable wood properties make E. pellita particularly suitable for plantation development in the wet tropical regions of south-east Asia. In spite the many positive traits, practical field observations indicate that the species is susceptible to end-splitting. There is some anecdotal evidence to suggest a genetic relationship with the incidence of end-split, although these observations were not statistically tested. This study evaluates the occurrence of end-splitting in five-year old plantation E. pellita in Sabah as affected by family and growth attributes. An existing progeny tree breeding trial, involving seeds that originated from Papua New Guinea, China, Vietnam, Australia, Sabah, and Sarawak with 106 families, was used to carry out the split assessment. Logs from the second thinning were cut into 2.2-m-long sections. The end splits were measured three days later; the incidence and severity of splitting were assessed at both the large and small ends of each log by using a designated split scoring system. The study shows that 99% of all log cross sections (per cut surface) experienced signs of splitting, with an average of 2.7 splits per cut surface. Overall, 54% of all splits were classed as ‘Three-Quarter Radial Splits’ while the occurrence of internal splits was negligible. Split severity showed a heritable and significant difference (h2 = 0.24 at p ≤ 0.05) among the family levels. Splitting was also significantly related to growth factors such as tree height and diameter at breast height (DBH). The findings suggest that end-splitting is caused by family–environment interactions. This offers the opportunity to improve the wood resource of E. pellita via breeding strategies.

ЛАНДШАФТНАЯ ХАРАКТЕРИСТИКА ГОРОДСКИХ ЛЕСОВ Г. РОСТОВ-НА-ДОНУ

The study of the composition of urban forest plantations in order to increase their productivity is one of the important tasks of forestry. The Rostov region belongs to the sparsely forested area (the forest cover of the territory is only 2.5%), the main part of the plantations (70%) is artificial forests. Taking into account the pace of urbanization, as well as the development of industry and agriculture in a million-plus city, urban forests not only perform the most important sanitary and hygienic functions (protection from wind and dust, noise reduction, soil protection from erosion processes, etc.), but also recreational facility for local residents. To conduct research, we used methods generally accepted in taxation, and the processing and analysis of the results obtained were carried out using the methods of mathematical statistics. This article presents a landscape characteristic of urban forest plantations in Rostov-on-Don: Shchepkinsky forest and Aviator Park. The taxation description of forest stands by sections is given. We determined the composition of plantations and identified the predominant tree and shrub species. The distribution of urban forests by land categories is presented: forest lands covered by forests and not covered by forests, as well as non-forest lands. We have classified plantings into groups: coniferous, hard-leaved and soft-leaved, as well as into age groups (young stands, pole stands, middle-aged, maturing, ripe, overmature). Most of the stands are deciduous species in the growth retardation stage with an age of about 70 years. Analysis of the obtained data shows that in the urban forests of Rostov-on-Don there is a lack of species diversity of tree and shrub vegetation, mainly coniferous plantations, as well as the introduction of introduced flora of both trees and shrubs. For the sustainable development of forest stands, landscape felling and mass planting of young stands are required.

Toposequence variability in tree growth associated with leaf traits for Larix gmelinii

Intraspecific variations in leaf traits and tree growth along environmental gradients are crucial for survival and distribution of the tree species, but they are substantially less quantified than interspecific counterparts. Here, we examined the intraspecific variations in leaf hydraulics and economics traits and growth of Larix gmelinii Rupr. – the predominant tree species in the Eurasian boreal forests with a toposequence approach. The toposequence included three replicated 1000-m transects of the larch plantation (31-year-old), each of which consisted of three plots located at the toe-, mid-, and top-slope, respectively. We found that the leaf hydraulics traits showed a “high-low-high” pattern along the toposequence, while the leaf economics traits, total biomass (TB) and TB increment (TBI) displayed an opposite trend, largely consistent with changes in site conditions especially soil nitrogen concentration. This suggests that the intraspecific variation in tree growth is coupled with leaf traits and site conditions. Leaf mass per area explained 21.9% of the variability in TB, while and the ability of drought tolerance explained 22.5% of that in TBI; and the interactions of hydraulic and economic variables explained additional 23.1–26.2% of that in TB or TBI. This result indicates that leaf traits interactively affect TB and TBI, but the hydraulics and economics play major roles in the short-term growth rate and relatively long-term biomass stock, respectively. Together, our findings demonstrate that the larch trees acclimate the leaf traits and growth/biomass accumulation to site conditions, and provide insights into the mechanistic understanding of forest production.

Сучасний стан насаджень дендропарку "Володимирівський" ДП "Гутянське лісове господарство" та перспективи його розвитку

Визначено сучасний стан, виявлено назрілі проблеми та встановлено пріоритети подальшого розвитку дендропарку "Володимирівський" державного підприємства "Гутянське лісове господарство". Проведено збір даних і впорядкування відомостей про досліджувану дендрологічну частину парку. На підставі аналізу дослідних даних визначено найважливіші цінності дендрологічної частини: природні, соціально-економічні, культурні, рекреаційні, естетичні, еколого-освітні; окреслено пріоритети щодо їх збереження, охорони та відтворення. Проаналізовано фактори впливу на цінності та функціональність дендрологічної частини лісового фонду із ранжуванням проблем. Виділено 21 просторовий складовий елемент. Територія дендропарку поділена на дві частини – заповідну (лісову прогулянкову) зону та зону регульованої рекреації, що умовно розділені модриновою алею, яка бере свій початок від центральної брами в північній частині парку і закінчується біля бесідки для відпочинку відвідувачів у південній частині. Підтверджено, що особливої природної цінності та неповторності парк набуває завдяки 12 дубам-велетням 100-річного віку, із середнім діаметром 56 см і середньою висотою 23,5 м, що утворили куртину площею 0,21 га. Проаналізовано стан панівної за площею породи Pinus sylvestris L. і встановлено, що насадження цієї рослини штучного походження 50-60-річного віку із чагарниковим підліском займає площу 0,28 га, а природні 8-12-річного віку – 3,35 га, що разом становить 3,63 га, або 51 % від площі дендропарку. Відзначено, що на площі 1,1 га сосна звичайна зростає із природним поновленням Betula pendula Roth., Populus tremula L., Acer platanoides, Acer negundo. З'ясовано, що серед зелених насаджень парку переважають деревостани ІІ класу віку, а переважаючою повнотою насаджень парку є повнота 1,0. За результатами оцінювання сучасного стану подано рекомендації щодо розвитку території дендропарку.

STAGES OF THE CURRENT STATE OF LAND FORESTRY PURPOSES AND FEATURES OF THEIR USE IN THE CONTEXT OF THE LEGAL REGIME

The article analyzes the structure of the land fund, the distribution of Ukraine's forest area by predominant tree species, and states that the division of land by categories is a dynamic process, whenever in the course of economic activity on land there may be a need to change its purpose. Determining and changing the ownership of a land plot to a certain category of land is the prerogative of public authorities - state and local self-government, which are endowed with such powers. The analysis of forest cover in Ukraine in terms of natural zones and structure of land for forestry purposes in Ukraine, where from the total area of forestry lands and forests on other categories of lands is 10.8 million hectares, of which 9.7 million hectares are covered with forest vegetation. The analysis of the given data testifies to an uneven arrangement of the specified category of lands of the territory of Ukraine. In particular, they are concentrated mainly in Polissya and the Ukrainian Carpathians.The stages of legal regulation and use of forest lands are proposed. Regarding the solution of these two problems lies in the plane of decision-making on land use, establishing a socially optimal purpose of land, compliance with land legislation, promoting reforestation and afforestation; stimulating the preservation and increase of forest land productivity, which requires the use of levers of influence on land and forest users; irrational use of forest lands, which leads to loss of potential benefits of the landowner.

Reduction of carbon absorption capacity of forest stands in Zhytomyr Polissya due to the pine stands mortality

According to the signed climate Paris Agreement, Ukraine is faced with the task to prevent the global average air temperature from rising above 2,0 °C in order to avoid an increase in droughts, extinction of certain species of plants and animals, drying up and diseases of tree species, etc. To preserve and increase the number of natural carbon sinks, scientists pay attention in particular to the system of improving forest, soil, and other natural resources management. Among thirty main forest-forming species in Ukraine, Scots pine (Pinus silvestris L.) is the predominant tree species, in Zhytomyr Polissya, in particular, its amount is 388,4 thousand hectares, which is 59 % of all tree plantations.
 To establish the carbon absorption capacity of pine plantations of Zhytomyr Polissya, we have laid temporary test squares (CCIs) in state-owned enterprises: Baran Forestry hunting enterprise; Belokrovytsia Forestry; Gorodnitsky Forestry; Emilchinskoye Forestry; Zhytomyr Forestry; Korostensky hunting enterprise; Malinsky Forestry; People's Specialized Forestry; Novograd-Volyn Experienced Forestry; Ovruch Specialized Forestry; Olevsky Forestry; Slovenian Forestry Agribusiness.
 According to the methods of P. I. Lakida, A. A. Storochinsky, O. I. Poluboyarynova, A. S. Atkin, A. I. Kobzar, we established a phytomass of pine plantations in a completely dry state and obtained conversion coefficients that made it possible to estimate the difference between CO2 emissions and carbon sequestration. 
 The statistical analysis showed homogenous average height, but not for other indicators. We found a very asymmetric right distribution in terms of age, density, bonity, Volume of the trunk, and phytomass, moderate distribution in terms of average diameter and left distribution for average height. The excess factor indicated an acute vertex distribution by density and a flat-top distribution by all other indicators.
 The total area covered by forest vegetation of pine forest areas is 388.4 thousand hectares (according to the latest accounting for 01.01.2011), with a total stock of stem wood 102.7 million m3, accumulate in their phytomass 23.5 million tons of carbon. The density of the phytomass per 1 m2 of forested vegetation is 52.7 kg. Medieval pine plantations absorb the most carbon in Zhytomyr Polissya — 12.1 million tons.
 In recent years, there has been an increase in lost areas covered with forest vegetation under pine trees due to the damage by biotic, abiotic and anthropogenic factors.
 The loss of pine forest plantations for various reasons reduces the carbon absorption capacity of Zhytomyr Polissya forests, as pine stands are the vast majority in the study area - 59%.
 It is established that pine forest plantations of Zhytomyr Polissya in their phytomass accumulate 23.5 million tons of carbon per year. The density of carbon per 1 m2 of forested vegetation is 25.7 kg.
 It is found that medieval pine plantations absorb the most amount of carbon in Zhytomyr Polissya — 12.1 million tonnes.
 It has been established that lost forest plantations due to anthropogenic, biotic and abiotic factors,between 2010 and 2018, could sequestrate 0.17-0.33 million tonnes of carbon in their phytomass reducing the level of CO2 pollution from 10 to 47 %.