Betula Ermanii Research Articles

Space exposure test of hardwood specimens in the International Space Station

To design a wooden satellite and select the appropriate wood species, we conducted a space exposure test of wood on the International Space Station (ISS). The space exposure test used the Japanese Experiment Module “Kibo” on the Exposed Experiment Bracket Attached on i-SEEP (ExBAS), which is connected to the exposed facility of the ISS. Three wood species considered candidates for the structure of a wooden satellite were used in the exposure test: honoki (Magnolia obovata), yamazakura (Cerasus jamasakura), and dakekanba (Betula ermanii). In the outgassing test conducted in preparation for the space exposure test, the collected volatile condensable materials (CVCM) of the three wood species were below the critical value; however, the total mass loss (TML) exceeded the critical value. However, this was not a problem, because most of the mass loss was due to water evaporation. A space exposure test was conducted for 10 months in 2022. Consequently, no change was observed in the weight of the exposed specimen, and no erosion due to atomic oxygen (AO) was observed. The exposure test was scheduled to be carried out in the forward direction of the ISS travel; however, owing to equipment trouble, it was installed in the opposite direction. This is because an insufficient AO flux collided with the specimen. In terms of wood color, the brightness of the three species decreased owing to space exposure, and saturation increased in two wood species, except for yamazakura. A thin-film layer was observed on the surface of the aluminum cover to which the exposed specimen was fixed, which may have also formed on the surface of the wood specimen, reducing its brightness. However, because the hue angle did not change significantly, only a slight deterioration of the surface layer owing to vacuum ultraviolet was observed. The results confirmed that the wood had hardly deteriorated in space for approximately 10 months.

Subfossil pollen spectra in the altitudinal belts of the Sikhote-Alin

This paper presents the characteristics and comparison of subfossil pollen spectra of modern plant communities in the altitudinal zones of the Northern Sikhote-Alin and the Southern Sikhote-Alin, using the cases of the Tordoki-Yani Mountain (absolute altitude 2090 m) and Oblachnaya Mountain (absolute altitude 1858 m). All pollen spectra from high mountains reflect the forests caused by long-distance transport of tree pollen. Due to the abundance of Picea pollen, the pollen spectra of the mountain tundra and upper part of the subalpine belts of the Northern Sikhote-Alin correspond to the most common type of vegetation at the upper forest borde r–the high-mountain spruce forest with Betula lanata, where Pinus pumila thickets can reach from the overlying belt. The largest amount of allochthonous pollen was found in the pollen spectra on the site without forest canopy. The pollen of broad-leaved trees was brought to high hypsometric levels by mountain-valley winds, rising air currents, from the underlying belts. The quantitative content of pollen of the main dominants of each altitudinal plant zone does not always accurately reflect the role of these taxa in the composition of the communities. The pollen productivity of Betula lanata exceeds the pollen productivity of the main forest forming species in all altitudinal zones, with the exception of the stone birch forests, therefore the share of its participation in the composition of the pollen spectra is overestimated. In the studied pollen spectra the content of Larix pollen is greatly underestimated compared to the role of this species in the forest stand, especially in soil samples from larch forest. It is associated with low pollen productivity, distribution and fossilization characteristics.

Pre-drought effects on northern temperate trees and vine invasion in forest gaps hindering regeneration

Northern temperate coniferous forests serve as crucial connectors between boreal and temperate forests, yet they are vulnerable to various stressors such as climate change and human activities. Severe drought poses a significant threat to plant species within these forests, prompting recent research into its impacts. However, many studies lack explicit definitions of post-disturbance vegetation processes and fail to identify potential interactions with disturbance factors, necessitating comprehensive discussions. This study examines the effects of drought on tree growth patterns of the main dominant species in northern temperate regions: Abies nephrolepis and Picea jezoensis, along with two commonly associated Betula ermanii, and Quercus mongolica. Additionally, new disturbance factors in forests inhabited by these species (A. nephrolepis and P. jezoensis) were evaluated based on community classification. The study sites were located in the Mt. Baekdu (Changbai) and South Korea regions, which are positioned at the southern limit of the phytogeographical patterns of target species. Results indicate that A. nephrolepis and P. jezoensis exhibit high levels of recovery and resilience, while B. ermanii and Q. mongolica demonstrate high resistance. Species-specific responses align with drought intensity, with resistance, recovery, and resilience decreasing notably with increasing pre-drought radial growth. South Korean forests, the invasion of the vine species Tripterygium regelii after the death of A. nephrolepis in the overstory vegetation threatens the regeneration of new trees. However, certain environmental factors, such as high rock exposure and dense overstory canopy, limit vine invasion. Based on the results, pre-drought radial growth emerges as a key determinant in how trees respond to drought. Additionally, the results suggest the potential for new disturbances to emerge in forest gaps due to overstory vegetation mortality induced by global warming. These findings contribute to a deeper understanding of increasing drought stress, aid in identifying climate refugia, and inform conservation priorities based on habitat characteristics.

Morphology and composition of calcium oxalate monohydrate phytoliths in the bark of Betula ermanii (stone birch): Case study from Sakhalin Island.

The morphology of calcium oxalate monohydrate precipitates (COM, Ca(C2O4)·H2O, P21/c, whewellite) occurring as crystals or intergrowths, as well as distribution of crystal-bearing idioblasts, have been studied for the first time in the bark of stone birch Betula ermanii from Sakhalin Island sampled in an area affected by mud volcanism and an unaffected typical forest environment taken for reference. The study addresses several issues (i) number and size of phytoliths and their distribution in different cell types; (ii) density of calcification in specific cells; (iii) habits of single crystals, twins, and complex intergrowths, as well as frequency of different morphologies and their relations. The trends of time-dependent morphological changes in separately analyzed crystals and intergrowths record the evolution of COM morphology from nuclei to mature grains. Of special interest are the nucleation sites and features of organic and inorganic seeds and nuclei for COM phytoliths. The precipitation process and crystal habits are mainly controlled by supersaturation, and it is thus important to constrain the Ca distribution patterns in different bark tissues. The B. ermanii samples were analyzed by several methods: scanning electron microscopy (SEM) for the distribution patterns and micromorphology of COM precipitates and bulk Ca content in bark; electron probe microanalysis (EPMA) for the mineral chemistry of COM precipitates; inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS) for trace elements in bulk bark and wood. RESEARCH HIGHLIGHTS: The distribution and morphology of whewellite precipitates in the analyzed B. ermanii bark samples indicate that the aqueous solution was most strongly supersaturated with respect to the Ca(C2O4)·H2O solid phase at the parenchyma-sclerenchyma boundary, where most of the COM spherulites are localized and often coexist with large single crystals and contact COM twins.

Response of stomatal density and size in Betula ermanii to contrasting climate conditions: The contributions of genetic and environmental factors.

As plant distribution and performance are determined by both environmental and genetic factors, clarifying the contribution of these two factors is a key for understanding plant adaptation and predicting their distribution under ongoing global warming. Betula ermanii is an ideal species for such research because of its wide distribution across diverse environments. Stomatal density and size are crucial traits that plants undergo changes in to adapt to different environments as these traits directly influence plant photosynthesis and transpiration. In this study, we conducted a multi-location common garden experiment using B. ermanii to (1) clarify the contribution of both environmental and genetic factors to the variation in stomatal density and size of B. ermanii, (2) demonstrate the differences in the plasticity of stomatal density and size among B. ermanii populations, and (3) understand how stomatal density and size of B. ermanii would respond to increased temperature and changing precipitation patterns. Genetic factors played a more significant role in stomatal size than environmental factors, suggesting that B. ermanii struggles to adjust its stomatal size in response to a changing environment. Our results also revealed a positive correlation between stomatal size plasticity and original habitat suitability, indicating that in B. ermanii populations in harsh environments exhibit lower adaptability to environmental shifts. Although stomatal density and size of B. ermanii showed the significant responses to increased temperature and shifting precipitation patterns, the response ranges of stomatal density and size to the environmental factors varied among populations. Our findings highlighted the interplay between genetic and environmental factors in determining the intraspecific variation in stomatal density and size in B. ermanii. This indicated that certain populations of B. ermanii exhibit limited stomatal plasticity and adaptability, which could directly affect photosynthesis and transpiration, suggesting potential population-specific fitness implications for B. ermanii under future climate change.

Impact of ash fallout of the 2023 Shiveluch volcano eruption (Kamchatka) on forest vegetation

The ash fallout of Shiveluch volcano (April 11, 2023, Kamchatka) is the most intensive volcanic ash fallout of the last 60 years. We present the results of the reconnaissance fi eld investigations supplemented with analyses of satellite images of the area for estimations of deposits distribution and area aff ected by the ash fallout. We also estimated the properties of fi ne grained ash of andesitic composition and its infl uence on the forest vegetation composed by Picea yezoensis (Siebold et Zucc.) Carrière, Larix cajanderi Mayr и Betula ermanii Cham. As a result of moderate- scale ash fallout in the forest (thickness of freshly deposited ash is 5–8 cm), the negative impact on vegetation was minimal because the ash was fi ne-grained and was deposited on a thick snowpack, and the leaves were not formed yet. The forest vegetation on lower elevations was not damaged at all but strong changes occurred in grass and bush vegetation. We have observed the diminished density of plant coverage, decreased size of grass vegetation and a decreased number of plant species. Calamagrostis purpurea (Trin.) Link. s. l., a broadly represented dominant species among grass vegetation, became less common, but Chamerion angustifolium (L.) Holub became more widespread. The possibility of small plants to grow through the ash layer turned out to be strongly reduced. Mosses and lichens in the forest have been buried under the ash, the recovery could take several decades. We have found a notable impact on plants by ash remobilized by strong wind, this impact is the strongest in the open areas and on forest edges. This process can continue for many years due to the large volume of the deposited ash covering the open spaces of the volcano foot.

Two Centuries of Winter Temperature Variability Inferred from Betula ermanii Ring Widths near the Forests/Tundra Ecotone in the Changbai Mountain, China

In this study, we constructed a ring-width chronology derived from Betula ermanii (BE) near the transitional zone between forests and tundra within the Changbai Mountain (CBM) region. This chronology was established utilizing 55 cores obtained from 30 trees. Our analysis of growth/climate responses underscores the pivotal role of the mean maximum winter temperature in influencing radial growth. Drawing upon these growth/climate associations, we reconstructed the mean maximum temperature series for December of the preceding year through January of the current year for the years 1787 and 2005 CE, employing a standardized chronology. During the calibration period (1960–2005), the reconstructed series exhibited an explained variance of 36%. This reconstruction provides crucial insights into historical temperature fluctuations within the study area. Our findings indicate that year-to-year temperature variations did not manifest synchronously along the altitude gradient of Changbai Mountain. Notably, the response to recent winter warming exhibited disparities with the altitude on Changbai Mountain. Specifically, the higher altitude range (1950–2000 m a.s.l.) displayed a response to warming around 1960, the mid-altitude range (765–1188 m a.s.l.) responded around 1975, and the lowest altitude (650 m a.s.l.) responded by 1977. Consequently, the paleotemperature research outcomes from Changbai Mountain alone may not adequately characterize climate change in this region. We recommend future high-resolution temperature records be obtained through sampling at various altitudes to enhance the comprehensiveness of our understanding.

Broad-leaved and mixed cooltemperate forests from the class Fagetea crenatae Miyawaki, Ohba et Murase 1964 on Kunashir Island (the Kurils archipelago)

This study presents the classification and description of three new associations of cool-temperate zonal forests of the vegetation class Fagetea crenatae Miyawaki, Ohba et Murase 1964 on Kunashir and Hokkaido islands. The Filipendulo camtschaticae–Aceretum mayrii ass. nov. encompasses broad-leaved forests in eutrophic moist ecotopes dominated by Acer mono subsp. mayrii. The Abieti sachalinensis–Quercetum crispulae ass. nov. represents zonal mixed forests dominated by Quercus mongolica var. crispula with an admixture of coniferous tree species Abies sachalinensis, Taxus cuspidata, and Picea jezoensis (the latter only on Kunashir Island, in forests of the subass. piceetosum jezoensis). The Hydrangeo paniculatae–Quercetum crispulae ass. nov. includes secondary species-poor forests dominated by Q. mongolica var. crispula, Betula ermanii, or B. pendula subsp. mandshurica. All associations feature a dense understory of dwarf bamboo species Sasa spp., with the densest tickets found in Hydrangeo paniculatae–Quercetum crispulae forests. We also validated the union Carpino cordatae–Quercion crispulae Takeda, Uemura et Nakanishi ex Korznikov, Dzizyurova et Petrenko all. nov. which represents the zonal cool-temperate broad-leaved and mixed forests in Hokkaido, Sakhalin, Iturup and Kunashir. Broad-leaved forests of Kunashir exhibit lower species diversity compared to Hokkaido, missing typical temperate tree species such as Acer palmatum, Carpinus cordata, and Tilia japonica.

Cryptic diploid lineage of Betula ermanii at its southern boundary populations in Japan.

Polyploidy is thought to enable species diversification and adaptation to extreme environments. Resolving the ecological differences between a taxon's ploidy levels would therefore provide important insights into local adaptation and speciation. The genus Betula includes many polyploids, but estimates of their phylogenetic relationships and evolutionary history are uncertain because of cryptic lineages and species. As one of the southern boundary populations of Betula ermanii in Japan has been shown to have distinctive genetic characteristics and traits, the differences in ploidy levels between three southern boundary and various other Japanese B. ermanii populations were investigated using flow cytometry. Leaf and seed morphologies were also compared. Apart from individuals in southern boundary populations, all those sampled were tetraploid. Individuals from the southern boundary populations were mostly diploid, apart from a few from lower altitude Shikoku populations, which were tetraploid. Leaf and seed morphologies differed between tetraploids and diploids. Diploid individuals were characterized by leaves with a heart-shaped base and many leaf teeth, and seeds with relatively longer wings. The diploid populations could be considered a cryptic relict lineage of B. ermanii, and there is a possibility that this lineage is a diploid ancestor of B. ermanii and a relict population of the Sohayaki element. Further investigation of the Japanese Betula phylogenetic relationships would enable an informed discussion of taxonomic revisions.

Differences in photosynthetic and water use characteristics of four co-existing tree species at the treeline of the Japanese Alps

ABSTRACT Physiological characteristics of trees in the alpine treeline are critical for assessing the vulnerability of alpine forest ecosystems, but differences in water relations between co-existing deciduous and evergreen trees remain poorly understood. In this study, we analyzed the photosynthetic and water use characteristics of two deciduous broad-leaved (Sorbus matsumurana and Betula ermanii) and two evergreen coniferous (Abies mariesii and Pinus pumila) tree species at the treeline – i.e. the line connecting the highest patches of forest composed of trees at least three meters high – of Mt. Norikura in central Japan, to explore the physiological adaptations of trees to alpine environments. We monitored diurnal changes in leaf gas exchange rates and leaf and soil water potentials in each tree species during the growing season, as well as bulk leaf water relations based on pressure – volume curves and whole-tree hydraulic structures. The four species under study relied on different physiological characteristics at both leaf and plant levels for adaptation to their natural habitat. For maintaining water in leaves, S. matsumurana showed higher water use efficiency (WUE; the ratio of photosynthesis to transpiration) and osmotic adjustment. In contrast, B. ermanii showed lower WUE, while maintaining higher soil-to-leaf hydraulic conductivity with less stomatal control. In turn, A. mariesii showed higher WUE and leaf succulence. Meanwhile, P. pumila showed lower WUE but compensated for water loss through higher leaf hydraulic capacitance and tissue elasticity. Our observations demonstrate that tree species rely on specific physiological characteristics to adapt to the alpine treeline environment.

Divergent mechanisms of reduced growth performance in Betula ermanii saplings from high-altitude and low-latitude range edges

The reduced growth performance of individuals from range edges is a common phenomenon in various taxa, and considered to be an evolutionary factor that limits the species’ range. However, most studies did not distinguish between two mechanisms that can lead to this reduction: genetic load and adaptive selection to harsh conditions. To address this lack of understanding, we investigated the climatic and genetic factors underlying the growth performance of Betula ermanii saplings transplanted from 11 populations including high-altitude edge and low-latitude edge population. We estimated the climatic position of the populations within the overall B. ermanii’s distribution, and the genetic composition and diversity using restriction-site associated DNA sequencing, and measured survival, growth rates and individual size of the saplings. The high-altitude edge population (APW) was located below the 95% significance interval for the mean annual temperature range, but did not show any distinctive genetic characteristics. In contrast, the low-latitude edge population (SHK) exhibited a high level of linkage disequilibrium, low genetic diversity, a distinct genetic composition from the other populations, and a high relatedness coefficient. Both APW and SHK saplings displayed lower survival rates, heights and diameters, while SHK saplings also exhibited lower growth rates than the other populations’ saplings. The low heights and diameters of APW saplings was likely the result of adaptive selection to harsh conditions, while the low survival and growth rates of SHK saplings was likely the result of genetic load. Our findings shed light on the mechanisms underlying the reduced growth performance of range-edge populations.

Responses of soil greenhouse gas emissions to soil mesofauna invasions and its driving mechanisms in the alpine tundra: A microcosm study

Climate change is resulting in significant modifications of the altitudinal patterns of soil fauna in mountains, leading to their upward invasion and alteration of soil ecological processes. However, the effects of soil greenhouse gas (GHG) emissions from soil mesofauna invasion and their driving mechanisms have not been clearly understood. To address this knowledge gap, we simulated a soil mesofauna invasion from an Erman's birch forest (EB) to the alpine tundra (AT) of the Changbai Mountain in Northeast China. Four treatments were established: no soil mesofauna (S0), native species (SN), invasive species (SI), and invasive species superposed native species (SS). We conducted a 79-day microcosm experiment, utilizing gas chromatography and high-throughput sequencing, to explore the variations in soil greenhouse gas emissions and their driving factors. Results showed that the cumulative CO2 emissions under SN, SI, and SS, compared with S0, increased by 34.13 %, 73.93 %, and 107.64 % and cumulative N2O emissions increased by 59.05 %, 101.18 %, and 183.88 %, respectively. Compared to SN, the cumulative emissions of CO2 and N2O increased by 29.89 % and 26.31 % under SI and by 54.91 % and 78.59 % under SS, respectively. The impacts of invasive species and native species on greenhouse gases were not a simple additive effect. Abiotic (soil variables) and biotic (soil mesofauna and microbial diversity) factors explained 37.76 % and 44.41 % of the total variations in CO2 and N2O emissions, respectively, in which NH4+-N and C: N ratios contributed the largest variations. The contribution of soil mesofauna diversity to the variations in CO2 and N2O emissions was higher than that of microbial diversity. The bacterial network graph density was correlated with soil CO2 and N2O emissions. Our findings highlight that soil mesofauna invasions increased GHG emissions, and these variations were predominantly explained by biotic rather than abiotic factors.

The composition of non-structural carbohydrates affects the respiration and morphology of tree fine roots in Japan Alps

Non-structural carbohydrates (NSC), such as soluble sugars and starch, are important drivers of physiological function and survival in woody plants. The soluble sugar and starch in the organs of woody plants might affect their resource acquisition, but little is known about their direct association with the fine root physiological function. Here, we aimed to quantify the storage of soluble sugar and starch in the fine roots of two woody species, found under the alpine treeline, namely, Maries' fir (Abies mariesii) and Erman's birch (Betula ermanii). We also set out to identify the relationship between each NSC and both fine root respiration and morphology of the plants. To this end, the concentrations of soluble sugar and starch, root respiration rate, and specific root length (SRL) were measured in three root diameter classes: <0.5, 0.5–1.0, and 1.0–2.0 mm. In both species, we found that the sugar concentration of <0.5 mm roots was lower than that in both 0.5–1.0 and 1.0–2.0 mm roots, whereas there were no clear differences in starch concentration among the three classes. Additionally, our results showed that the sugar concentration was negatively correlated with the root respiration rate and SRL, whereas starch concentration did not show any correlation with these factors. Altogether, these findings suggest that the soluble sugar in fine roots can act as a direct source of energy for the roots to aid soil resource acquisition, whereas the starch can serve as an indirect, longer-term storage reservoir. Such distinct differences in the storage and function of soluble sugar and starch in fine roots are likely to improve our understanding of the sink-size of each process in terms of carbon consumption for root respiration and root morphology for soil resource acquisition.

Within-species plant phylogeny drives ectomycorrhizal fungal community composition in tree roots along a timberline

Fungal community structure in tree roots and in surrounding soils is constrained significantly by plant phylogenetic relationships among multiple species. However, whether plant phylogenetic relationships within a single species can mediate fungal community structure has not been investigated. Here, we surveyed ectomycorrhizal (EcM) and saprotrophic (SAP) fungal community structure in fine roots and in neighboring soils of Betula ermanii along the Changbai Mountain timberline. When accounting for the effects of soil properties, root traits, and geographic distance, within-species plant phylogeny was the sole driver of EcM fungal community composition in roots, whereas geographic distance was the strongest driver of SAP fungal community composition in soils and roots. Deterministic processes were dominant in root EcM fungal community assembly, and stochastic processes were dominant in SAP fungal community assembly. Overall, the findings demonstrate that within-species plant phylogeny drives EcM fungal community composition in roots, and fungal community assembly is both guild- and habitat-dependent.

Liverworts of the South Kamchatka Nature Park: Survival in Active Volcanism Land

Kamchatka, due to its position in hemiarctic northeast Asia on the migration pathways of taxa from Asia to America and vice versa, which has an insular geographical position and provides numerous pieces of evidence regarding current active volcanism, has a peculiar flora. The study of the liverwort flora of the southeastern part of the Kamchatka Peninsula (South Kamchatka Nature Park), which, until now, has been very poorly explored, showed high taxonomic richness and some specificity due to volcanic evidence. In total, 132 species have been recorded in this sector of the “Pacific Ring of Fire”. This number is quite high compared to other floras of hemiarctic Asia. The influence of volcanism on flora formation is prominent due to the regular renewal of substrates, the appearance of specific habitats (for example, thermal water outlets), the displacement of vegetation belts, and ashfalls leading to the presence of extended spaces free of vegetation cover and is an area that is open for invaders. The altitudinal zonality, despite the difference of 2000 m in elevation, is not clearly expressed in the flora of the liverworts: arctomontane species descend far down the altitudinal profile, reaching the Betula ermanii forests. The “plantless” uppermost belt in the mountains, commonly described in floristic studies of vascular plants, is not actually free of plants if liverwort occurrences are considered. A number of species normally occupy unusual habitats in the studied flora due to contemporary volcanism evidence, e.g., sulfur-rich substrates.

Database and primer selections affect nematode community composition under different vegetations of Changbai Mountain

High-throughput sequencing technology is increasingly used in the study of nematode biodiversity. However, the annotation difference of commonly used primers and reference databases on nematode community is still unclear. We compared two pairs of primers (3NDf/C_1132rmod, NF1F/18Sr2bR) and three databases (NT_v20200604, SILVA138/18s Eukaryota and PR2_v4.5 databases) on the determination of nematode community from four different vegetation types in Changbai Mountain, including mixed broadleaf-conifer forest, dark coniferous forest, betula ermanii Cham and alpine tundra. Our results showed that the selection of different primers and databases influenced the annotation of nematode taxa, but the diversity of nematode community showed consistent pattern among different vegetation types. Our findings emphasize that it is necessary to select appropriate primer and database according to the target taxonomic level. The difference in primers will affect the result of nematode taxa at different classification levels, so sequencing analysis cannot be used for comparison with studies using different primers. In terms of annotation effect in this study, 3NDf/C_1132rmod primers with NT_v20200604 database could provide more information than other combinations at the genus or species levels.

Which Is the Best Substrate to Regenerate? A Comparative Pot Experiment for Tree Seedling Growth on Decayed Wood and in Soil

Dead wood is an important microsite for seedling regeneration in forest ecosystems. Although recent studies have found important associations between fungal wood decay type (white rot and brown rot) and both density and species composition of regenerating seedlings, its abiotic and biotic mechanisms are unknown. In the present study, pot experiments were conducted with the seedlings of two ectomycorrhizal tree species (Abies veitchii and Betula ermanii) and two arbuscular mycorrhizal tree species (Chamaecyparis obtusa and Cryptomeria japonica) to evaluate their growth using three substrates: brown rot wood, white rot wood, and soil. Results showed that the shoot growth of B. ermanii grown in white rot wood was greater than in other substrates, but this effect disappeared in sterilized substrates, suggesting some biotic positive effects occur in white rot wood. The seedling weights of Cr. japonica and Ch. obtusa were found to be greater in soil than in wood, and this may be partly attributable to the high mycorrhizal rate of their roots in soil. Colonization of arbuscular and ectomycorrhizal fungi was restricted to the seedlings in unsterilized soil. These results demonstrate the importance of the biological mechanisms affecting seedlings’ preferences for a variety of regeneration microsites and illustrate the need for future experiments to include larger sets of seedling species.

국립공원 아고산대 독립훼손지 복원식생 분포특성 및 관리방안

This study was conducted to provide basic data for mid-to long-term monitoring and establishment of management plans by analyzing the existing vegetation and identifying the vegetation distribution characteristics for the restored vegetation in Nogodan and Seseokpyeongjeon in Jirisan National Park located in the subalpine zone among the independent damaged areas. Actual vegetation survey range was established in consideration of the distribution of the watershed around the damaged area. The surveyed area of Seseokpyeongjeon was 55,037㎡, and the surveyed area of Nogodan was 166,599㎡. In Seseokpyeongjeon, the vegetation coverage by the herbaceous layer was almost 90% or more, there was no bare exposure, and the coverage of the shrub layer was stabilized at 60% or more. The main emerging tree species were planted species such as Abies koreana, Betula ermanii, Fraxinus sieboldiana, Rhododendron schlippenbachii, Rhododendron mucronulatum var. ciliatum, and Weigela florida as well as natively migrated native species. In Nogodan, the shrub vegetation dominated by Quercus mongolica, Salix caprea, Rhododendron schlippenbachii, Rhododendron mucronulatum var. ciliatum, and Tripterygium regelii was the most widely distributed with 52% of the area, and the overall diet was good. The native vegetation of Nogodan was presumed to be a cypress colony. Naturalized plants were distributed in the military base demolition site, so active management was required. The study site was predicted to develop into a vegetation landscape in harmony with the surrounding natural vegetation in the long term. In the future, the restoration model for damaged areas should be set in consideration of the native vegetation of the nearby area, but the goal to achieve restoration should be set at a feasible level.

СТРУКТУРНЫЕ ОСОБЕННОСТИ КОРЫ ОДНОЛЕТНЕГО СТЕБЛЯ BETULA ERMANII CHAM. ПОД ВОЗДЕЙСТВИЕМ ГАЗО-ГИДРОТЕРМАЛЬНЫХ ВЫХОДОВ ВУЛКАНА БАРАНСКОГО

The authors studied structural changes in the tissues of bark of annual stem Betula ermanii Cham. (Betulaceae Gray) under various environmental conditions. They collected the Betula ermanii samples in typical for this species conditions, characteristic of the Sakhalin Island, Krasnaya Mountain, Starozavodsky solfatara field, Baransky Volcano on the island of Iturup, and the Blue Lakes thermal springs area. A comparative quantitative analysis of the anatomical features of bark of annual stem made it possible to identify unidirectional structural changes in the conditions of gas-hydrothermal outcrops of Baransky Volcano, both upward and downward. These parameters include a number of crystals in cortex and phloem parenchyma, sieve tube diameters, the total number of ph loem rays and the uniseriate rays’ quantity, and the length of uniseriate phloem rays. The rest of bark tissue parameters of annual stem Betula ermanii from the studied habitats either showed no significant change, or changed in only one of the habitats with unfavorable conditions. The phellem width, the number of phellem cells in the radial row, and width of secondary phloem are modified in the Starozavodskoye solfatara field. The specific area of protophloem fibers and sclereids is changed under the conditions of thermal Blue Lakes. Thus, the structural response of annual stem Betula ermanii bark under extreme conditions of gas-hydrothermal springs associates mainly with a change of secondary phloem traits – sieve tubes and ray parenchyma parameters.

Secondary phloem traits in mature stems of Betula ermanii in stressful environments of volcanic activity

This research summarizes the results of study of structural peculiarities of Betula ermanii growing around Baransky Volcano close to the thermal Golubye Ozera. We have performed statistical analysis of parameters of the secondary phloem of multiyear shoots and stems and found some features tied to extreme environmental conditions. We have found that structural reaction of the secondary phloem of multiyear shoots and stems of B. ermanii to the extreme conditions of post-volcanic activity of Baransky Volcano manifests itself as changes in the geometry of the conductive elements and dilatation of the radial parenchyma in the non-conductive phloem. We believe these changes to be adaptive in nature due to the need for increased conductivity in volcanic landscapes.