Quercus Mongolica Research Articles

Phenology advances uniformly in spring but diverges in autumn among three temperate tree species in response to warming

Predicting the length of growing season to further warming relies on both spring and autumn phenological responses of different species, but with little experimental evidence under different levels of warming. Here, the timing of spring phenology including budburst and leaf unfolding, and autumn phenology including leaf coloration and leaf fall, were examined in 2-year-old seedlings of three temperate tree species (Fraxinus mandschurica, Quercus mongolica, and Juglans mandshurica) that were grown in the field under warming conditions (W0, ambient; W2, +2°C; W4, +4°C). Our study showed that warming advanced budburst and leaf unfolding by 9 and 8 days in the W2 treatments and by 13 and 15 days in the W4 treatments, respectively, with the magnitude varied greatly among species. However, we found a delayed autumn leaf senescence only for Q. mongolica, for which leaf coloration and leaf fall delayed by 19 and 6 days and by 17 and 12 days in the W2 and W4 treatments, respectively. The temperature sensitivity of budburst declined with increasing temperature in Q. mongolica. The growing season was extended by 7–18 and 10–25 days in W2 and W4, primarily through the advancement of spring phenology. Warming increased budburst synchrony, such that J. mandshurica, which typically has the earliest leaf emergence, lost its growth and competitive advantages over the more phenologically plastic species, F. mandschurica and Q. mongolica. Our results provide new insights into the effects of elevated temperatures on phenological shifts and their potential influences on tree species recruitment and forest structure and composition.

Differences in the Quality, Yield, and Soil Microecology of Ginseng in Different Planting Environments

The quality and yield of ginseng are significantly affected by ecological factors, especially soil, which is a complex environment. This study compared the quality, yield, and soil differences of ginseng in a Mongolian oak forest (MOFG), birch forest (BFG), mixed wood forest (MWFG), poplar forest (PFG), farmland (FlG), and a felling forest (DfG). Based on these differences, the relationship between the three was explored, as was the most suitable forest type for developing understory ginseng cultivation. The soil bacteria diversity of DfG was similar to that of understory ginseng, and its ginsenoside content was at the same level as that of understory ginseng. The soil pH of FlG was significantly lower than that of the other five cultivation methods, and the soil bacteria were also different from them, especially those related to the nitrogen cycle. Ginsenoside Rg2 has a significant correlation with many soil factors and is sensitive to soil environmental differences. In conclusion, there were significant differences in the quality, yield, and soil environments between the different planting methods. MOFG was the most suitable for planting with excellent quality and high yield, while BFG was the worst; as such, planting in BFG should be avoided.

Interspecific Differences of Stem Diameter Variations in Response to Water Conditions for Six Tree Species in Northeast China

It is important to understand the response of stem diameter variations in dominant tree species to water conditions in Northeast China. The results will provide basic information for scientific predictions of the future development trend of temperate forests in the eastern mountainous area of northeast China. We employed a high-precision dendrometer to continuously monitor the stem radial changes of six dominant tree species in temperate forests in northeast China from 15 April to 24 October in 2021. Precipitation significantly promoted the tree stem diameter increment. The increment of stem diameter in Juglans mandshurica Maxim., Quercus mongolica Fisch. and Betula platyphylla Suk. had a significantly positive correlation with cumulative precipitation. Correlation analysis revealed that the stem radial change (SRC) of six tree species was positively correlated with precipitation (Pre) and relative humidity (RH), and negatively correlated with water vapor pressure deficit (VPD), indicating that the diameter growth of the six tree species was mainly restricted by water conditions. Under drought stress, the stem radial growth rate of the six tree species slowed down, the growth duration decreased and the tree water deficit (TWD) value increased, while there were obvious interspecific differences. Therefore, water conditions limited the stem radial growth of the six tree species, while each tree species had a different response to drought stress.

Community Structure and Growth Rate of Korean Quercus mongolica Forests by Vegetation Climate Zone

Q. mongolica forests are representative forest types in Korea, belonging to the intermediate succession stage with the highest species diversity. Identifying the community structure and growth rate of Q. mongolica forests by the vegetation climate zone can help in planning efficient forest restoration strategies for each vegetation climate zone. The proportions of major communities based on the vegetation climate zones newly adjusted by the Korea National Arboretum in 2020 were determined. Major dominant species were identified in Quercus mongolica forests in which Q. mongolica dominates by more than 50% by analyzing the importance based on the basal area of the trees using data from the 7th National Forest Inventory Survey. The basal area growth rate was analyzed for permanent sample plots from the 5th to 7th National Forest Inventory Surveys. The analysis revealed statistically significant differences in the basal area growth rate by vegetation climate zone over a 10-year period. However, it should be noted that Q. mongolica forests with younger age classes were more abundant in the warm southern temperate zone; thus, it is likely that age class has a greater effect on the rate of basal area increase than the vegetation climate zone.

The Funga of Higher Fungi of Mt. Jeombong in Korea: A Survey of Mongolian Oak Forest in 2017

This research was conducted to determine the biodiversity of higher fungi at the supersite of Mt. Jeombong from July to October 2017 during the second long-term ecology research by the National Institute of Ecology under the management of the Ministry of Environment of Korea. Forty-three families, 74 genera, and 130 species of higher fungi were found within the permanent square area of Mt. Jeombong and a 10 m radius of the ecological flux tower. Russulaceae (54 species, 21.9%), Amanitaceae (17 species, 6.9%), and Boletaceae (17 species, 6.9%) were the top three species taxa found in mycorrhizal mushrooms. Mycenaceae (nine species, 8.5%), Polyporaceae (11 species, 4.5%), and Strophariaceae (11 species, 4.5%) were the top three species taxa found in saprophytic mushrooms. These results were analyzed and compared with those of previous fungal mushroom studies.

Discomycetes of the Livadiysky Ridge (Primorye Territory, Russia)

The article presents the results of a revision of the collection of discomycetes found in plant communities of the subalpine belt of the Livadiysky Ridge. The ridge is located in the south of Primorye Territory and is characterized as an area with well-preserved southern indigenous Far East vegetation in its lower belt. In the volume of the studied 118 specimens, 62 species were identified, among which are both widespread and new to Primorsky Krai. To date, 79 species of discomycetes are known to occur in the plant communities of the Livadia ridge. The list of species known in the mycobiota of Primorye Territory was supplemented by five taxa, of which three are new for the Far East region of Russia (Ciborinia candolleana, Paragalactinia michelii, Sphaerosporella hinnulea). For a number of rare species, new locations were noted. Thus, the second collection point in the region was indicated for Cenangium ferruginosum (on dead wood of Quercus mongolica) and for Sclerencoelia fascicularis (on dead wood of Populus sp.).

Growth versus storage: response of Pinus tabuliformis and Quercus mongolica seedlings to variation in nutrient supply and its associated effect on field performance

Growth versus storage: response of Pinus tabuliformis and Quercus mongolica seedlings to variation in nutrient supply and its associated effect on field performance

Non-Structural Carbohydrates and Growth Adaptation Strategies of Quercus mongolica Fisch. ex Ledeb. Seedlings under Drought Stress

Under drought stress, plants can change their morphology, physiological characteristics, and carbon allocation to maintain survival and growth. Non-structural carbohydrates (NSC) are major substrates for plant metabolism and play an important role in seedling survival and growth under drought conditions. Mongolian oak (Quercus mongolica Fisch. ex Ledeb.), a constructive species distributed in northeast China, has a high drought tolerance. However, studies on seedling growth and the NSC dynamics of Mongolian oak under different drought intensities and durations are limited. To investigate this, our study measured photosynthetic characteristics, growth, biomass, and NSC concentrations for Mongolian oak seedlings on the 0, 15th, 30th, 45th, and 60th day of the experiment under three soil moisture conditions [75% ± 5% (CK), 50% ± 5% (W1), and 23% ± 5% (W2) of soil moisture field capacity (FC)]. Results showed that the growth and biomass gradually decreased as the soil moisture decreased, but the root: shoot ratio and root biomass allocation ratio gradually increased. In the W1 treatment (moderate drought), NSC content in the stems and taproots was 7.42% and 16.39% higher than those in CK at 60 days. However, in W2 treatment (severe drought), NSC content in the stems and taproots was significantly higher than those in CK during the whole period (p < 0.05), and they were 14.14% and 26.69% higher than those in CK at 60 days. We found that, under drought stress, Mongolian oak seedlings had lower growth but higher allocation to root biomass and higher NSC content in stems and roots. Furthermore, the root system became a vital carbon sink under drought stress and was beneficial for seedling survival.

The dynamics of wild populations of Henosepilachna vigintioctomaculata Motch. (<i>Coleoptera:Coccinellidae</i>) in Primorsky Krai

Relevance. Population dynamics (population waves) is an intrinsic quality of population systems. These fluctuations can be induced by various factors, e.g. environmental conditions and resource availability, elements of a food chain from the same or a higher level (competitors, parasites, predators), and diseases. Few researchers have addressed the issue of the population dynamics of Henosepilachna vigintioctomaculata in the Russian Far East. This paper investigates the reasons why the potato ladybird beetle became a pest of introduced cultivated plants.Materials and methods. To collect data on imagines, all research sites were examined at intervals of eight days during the entire period of the study. The examination of the research sites was conducted within one day. All the imagines taken from host plants were marked at the first encounter by puncturing their elytra with a sewing needle (0.4 mm in diameter) according to Hirano. The next generation of beetles was marked with nail polish (in two-three days after emergence) to avoid traumatizing the insects. At the second encounter, these beetles were also marked by puncturing their elytra with a needle. The methods implemented did not have an adverse effect on the survivability of the studied imagines. The beetles were released to the same plants where they had been taken from. The research data were analyzed by Jolly’s method.Results. Overwintered imagines appeared in the fields and began ovipositing at the end of May. The first generation of imagines appeared at the end of June – the begging of July. The second generation of imagines could be observed at the end of July – the beginning of August. A part of the imagines migrated to overwintering sites without ovipositing approximately at the end of August. The overwintered beetles were observed to emerge on the Mongolian oak Q uercus mongolica, the greater celandine Chelidonium majus, and the bird cherry Prunus padus. A typical primary biotope of the potato ladybird beetle was a potato field at the stage of vegetative growth (5-7 leaves) surrounded by the couch grass Elymus repens, the common dandelion Taraxacum officinale, and the perennial sow-thistle Sonchus arvensis. Marking the overwintered and new generations of imagines showed that the presence of the potato ladybird beetle in an ecosystem depended on agricultural and agrometeorological conditions.

Genome-Wide Identification and Expression Analysis of the bHLH Transcription Factor Family and Its Response to Abiotic Stress in Mongolian Oak (Quercus mongolica)

The basic helix-loop-helix (bHLH) family, one of the largest families of transcription factors in plants, is extensively involved in the growth, development, and stress response of several woody plants. However, no systematic analysis of the bHLH gene family in Quercus mongolica has been reported. We characterize QmbHLH genes and identify the functions of QmbHLH proteins in Q. mongolica. We used bioinformatics approaches, qRT-PCR analysis, and RNA sequencing data to examine chromosomal distributions, gene structures, and conserved patterns, and identified 89 QmbHLH genes, which were divided into 21 subgroups based on the phylogenetic analysis of bHLH genes in Arabidopsis thaliana. Segmental replication played a more prominent role than tandem duplication in the expansion of the QmbHLH gene family. Based on patterns of tissue-specific expression, protein interactions, and cis-element analysis, QmbHLH genes may be extensively involved in the growth and development of Q. mongolica. In leaves, stems, and roots, 12 selected QmbHLH genes exhibited responsiveness to abiotic stresses (salt, cold, weak light, and drought). Our study facilitates follow-up functional investigations of the bHLH gene family in Q. mongolica and provides novel insights into bHLH superfamilies in woody plants.

Modeling knot features using branch scars from Mongolian oak (Quercus mongolica).

Wood quality is an important indicator for modern sawmills. Internal wood characteristics can be derived from their correlations with external appearances. In this study, we developed linear regression models to predict knot size from surface features of Mongolian oak (Quercus mongolica) using data collected from 53 trees. For this, manual measurements and X-ray computed tomography scanning technology was respectively used to obtain internal and external features of 1,297 knots. Our results showed that Mongolian oak knots were generally concentrated in the middle part of oak stems, with fewer knots observed at the top and base. The parameters of knot and scar showed significant correlations (P<0.01), where length and diameter of the corresponding external scar increase with increasing the length and diameter of a knot. The corresponding external scar can be used as an effective indicator to predict the internal value of oak logs. The accuracy of our constructed model is more than 95% when assessed against independent test samples. These models thus can be applied to improve the practical production of oak timber and reduce commercial loss caused by knots. These additional data can improve the estimation of the influence of knots on wood quality and provide a theoretical foundation for investigating the characteristics of hardwood knots.

Effects of habitat differences on the scatter-hoarding behaviour of rodents (Mammalia, Rodentia) in temperate forests.

To discover the differences in hoarding strategies of rodents for different seeds in different habitats, we labelled and released three different types of seeds, including Pinuskoraiensis, Corylusmandshurica, and Quercusmongolica, in temperate forests of northeastern China and investigated the fate of seeds in four different habitats that included a broad-leaved forest, mixed-forest edge, mixed forest, and artificial larch forest. Our research showed that the hoarding strategy of rodents was found to vary substantially in different habitats. The survival curves of seeds from different habitats showed the same trend, but the rates of consumption in different habitats varied. More than 50% of the seeds in the four habitats were consumed by the tenth day. It took 20 days to consume more than 70% of the seeds. The rate of consumption of P.koraiensis seeds reached 96.70%; 99.09% of the C.mandshurica seeds were consumed, and 93.07% of the Q.mongolica seeds were consumed. The seeds were consumed most quickly in the artificial larch forest. In general, most of the early seeds were quickly devoured. After day 20, the consumption gradually decreased. Rodents found the seeds in the artificial larch forest in a shorter average time than those in the other types of forests. The average earliest discovery time was 1.4 ± 0.9 d (1-3 d). The average earliest discovery time in all the other three habitats exceeded 7 d. The median removal times (MRT) was distributed around the seeds at 14.24 ± 10.53 d (1-60 d). There were significant differences in the MRT among different habitats. It was shortest in the artificial larch forest at 7.67 ± 6.80 d (1-28 d). In contrast, the MRT in the broad-leaved forest was the longest at 17.52 ± 12.91 d (4-60 d). There were significant differences in the MRT between the artificial larch forest and the other habitats. There was less predation of the three types of seeds at the mixed-forest edge, and the most seeds were dispersed. The rates of predation of the P.koraiensis, C.mandshurica, and Q.mongolica seeds were 28.33%, 15.83%, and 44.0%, and 59.17%, 84.17%, and 48.0% of the seeds were dispersed, respectively. The average dispersal distances of all the seeds were less than 6 m, and the longest distance recorded was 18.66 m. The dispersal distances and burial depths differed significantly among the four types of habitats. The distance of seed dispersal was primarily distributed in 1-6 m.

Chemical Elements Recorded by Quercus mongolica Fisch. ex Ledeb. Tree Rings Reveal Trends of Pollution History in Harbin, China

Rapid industrialization has led to a dramatic increase in air pollution. In China, the factors driving the abundance and composition of smog, particularly fine particulate matter, remain poorly understood, and short-term air pollution data are available from few air quality monitoring networks. Using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), chemical elements (Mg, Al, Si, S, K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Sr, Tl, Pb, Bi) were analyzed in Quercus mongolica Fisch. ex Ledeb. tree rings from Harbin, China, in latewood at 5-year resolution over the period 1965–2020. The temporal trend of some elements was influenced by physiological factors, by environmental factors such as pollution, or influenced by both. Mg, K, Zn, Cu, Ni, Pb, As, Sr and Tl showed changes in pollution levels over time. The signal of K, Zn, Ni, Cu and Pb in trees from Harbin statistically did not differ from those at the control site after the 2000s. Our analysis confirmed the success of the undertaken emission reduction measures, which lead to an improvement in China’s urban air quality after 2010. However, As increased from 2000 to 2020 in Harbin which is consistent with rising As concentrations in China. Our study proved that dendrochemistry is a reliable tool to monitor the long-term history of pollution and to contribute to extending instrumental records of pollution back in time.

РЕЗУЛЬТАТЫ МОНИТОРИНГА УРОЖАЙНОСТИ ДУБА МОНГОЛЬСКОГО – ОСНОВЫ КОРМОВОЙ БАЗЫ КОПЫТНЫХ ЖИВОТНЫХ В ЗАПОВЕДНИКЕ «БАСТАК»

The Mongolian oak Quercus mongolica Fisch. ex Ledeb. along with the Korean pine, Pinus koraiensis Siebold et Zuss form the ecosystem integrity basis at the Bastak Reserve. The study of these species productivity is important and relevant. Currently, a number of articles have been published on the Korean pine nut productivity in the protected area. However, the information concerning the Mongolian oak yield is available only in the Annals of Nature. This paper presents the assessment data on the Mongolian oak acorns yield as a fodder base for a number of wild animals being the nutrition for the Amur tiger. This species productivity monitoring has been carried out at Bastak Nature Reserve since 2015. However, the first acorn harvest was obtained only in 2017. The assessment is made on permanent transects in different areas of the reserve. The research shows that monitoring of the Mongolian oak harvest in the Bastak reserve is carried out irregularly. The productive and lean years alternation trend has not been determined yet, unlike in the Lazovsky Reserve. Perhaps, because of a short monitoring period. The Mongolian oak acorns yield is significantly influenced by the weather conditions, primarily, the absence of rainy days during the flowering period. It is noted that in the absence of Mongolian oak acorns yield there is a good harvest of pine nuts partially compensating the absence of acorns as a nutrition for ungulates. However, maintaining a stable density of ungulates needs certain bio-technical measures, such as feeding grounds.

Convolutional neural network tree species identification based on tree-ring radial section image features.

Convolutional neural networks can automatically identify tree species based on the images of structural features of tree-rings samples. In this study, we used a tree-ring image dataset for different species to achieve tree-ring based species automatic identification with high accuracy by four convolutional neural network models (LeNet, AlexNet, GoogLeNet, and VGGNet), aiming to determine the identification accuracy of the models, clarify the species misidentification during the automatic processes, and explore the identification differences among the models. The results showed that tree species identification derived from the trained convolutional neural network models was reliable, with the GoogLeNet and LeNet showed the highest (96.7%) and lowest (66.4%) identification accuracy. The tree species identifications using different models were highly consistent. Quercus mongolica and Abies nephrolepis showed the highest (100% for AlexNet) and lowest identification accuracy, respectively. Misidentification could occur among tree species with similar tree-ring structure. The identification accuracy of the models was higher at family and genus levels than that at the species level. The identification accuracy of broadleaf tree species was higher than that of coniferous trees due to distinct radial structure among broadleaf species. Overall, our method achieved a high accuracy for tree species identification, and provided a fast, convenient, and automatic tree species identification by detecting specific tree-ring properties with convolutional neural network.

Correlation between litter decomposition rate of &lt;i&gt;Quercus mongolica&lt;/i&gt; leaf and microclimatic factors at Mt. Jeombongsan

Correlation between litter decomposition rate of &lt;i&gt;Quercus mongolica&lt;/i&gt; leaf and microclimatic factors at Mt. Jeombongsan

Vegetation community dynamics during naturalized developmental restoration ofPinus tabulaeformisplantation in North warm temperate zone

AbstractThe study is to explore the dynamics of community structure, diversity, interspecific relationships and stability during naturalized developmental vegetation restoration which realized by natural interaction between plantation and native trees without human’s involvement. The naturalized developmental restored forests in Baxianshan National Reserve were divided into three typical stages (i.e. Pinus tabulaeformis forest stage, mixed forest stage and near-natural forest stage) according to the ratio of P. tabulaeformis coverage to arbor layer, and the zonal natural secondary forests for control. According to the data of each wood gauge, we focused on the dynamics of community in terms of structure, diversity and stability. We found that, (i) The composition of dominant populations kept stable since the mixed forests stage and the α-diversity increased with restoration; (ii) The diameter class structure of tree layer exhibited a tendency of bell-shaped type toward inverted J-type, indicating an active regenerating and developmental status; (iii) Niche width of dominant populations such as Juglans mandshurica, Quercus mongolica, Quercus variabilis and Tilia amurensis increased during restoration, while that of Quercus dentata population decreased after playing a pioneer role; (iv) The proportion of negative association and high niche overlapped population pairs (&amp;gt;0.5) both decreased with restoration. In summary, naturalized developmental restoration has promoted the actively developing and regenerating of populations and improved the healthy restoration of plantation community. The status and interrelationships of populations were still being adjusted. The results provide a reference for revealing the dynamic characteristics of vegetation community development in naturalized developmental restoration of plantations.

Russula rubiginosus sp. nov. in Russula subsect. Maculatinae from Heilongjiang Province, Northeast China

Russula rubiginosus sp. nov. (Subsect. Maculatinae) associated with Quercus mongolica is described and illustrated based on phylogenetic analyses of internal transcribed spacer (ITS) ribosomal DNA sequences and morphological evidence. This species is characterized by the rusty spots on the pileus and stipe, an acrid taste, a yellow spore print, smaller basidiospores, and abundant cystidia in pileipellis and stipitipellis. Furthermore, the morphological characteristics were described in detail and compared with R. globispora and R. subrubescens.

Effects of warming, photoperiod, and nitrogen addition on the main phenological phases of Quercus mongolica

With a large artificial climate chamber, we examined the effects of warming (control, +1.5 ℃, +2.0 ℃), photoperiod (10, 14, 18 h) and nitrogen addition (0, 5, 10, 20 g N·m-2·a-1) on the main phenological phases of Quercus mongolica in Northeast China. The results showed that 1.5 and 2.0 ℃ warming significantly advanced the bud swelling stage and delayed the leaf fully coloring stage, which prolonged the growing season. The extended days increased with the increases of warming range. Photoperiod significantly affected autumn phenology (leaf coloration onset stage, leaf coloration in general stage, leaf fully coloring stage). Compared with photoperiod of 14 h, short photoperiod (10 h) significantly delayed leaf coloration onset stage by 7.0 d, and prolonged the peak of growth season. Nitrogen addition significantly advanced the bud swelling stage, bud opening stage, first leaf unfolding stage and full leaf unfolding stage. The leaf fully coloring stage was significantly delayed by 9.5 d only at the high nitrogen level of 20 g N·m-2·a-1, indicating that high nitrogen addition prolonged the growing season of Q. mongolica. The synergistic effects of warming and high nitrogen addition (20 g N·m-2·a-1) significantly delayed the leaf fully coloring stage, which prolonged leaf coloration stage, and the synergistic effects of warming and short photoperiod, the synergistic effects of nitrogen addition and short photoperiod. The synergistic effects of warming, nitrogen addition and short photoperiod all significantly delayed the leaf coloration onset stage, which relatively prolonged the peak of growing season.

Ectomycorrhizal fungi enhance salt tolerance of Quercus mongolica by regulating ion balance

We explored the effects of salt stress on the growth of Quercus mongolica and the effects of ectomycorrhizal fungi (ECMF) on the ion balance of Q. mongolica. After inoculating four kinds of ECMFs (Gomphidius visci-dus, Suillus leteus, Suillus grevillea, Boletus edulis) on Q. mongolica seedlings, we treated the annual non-mycorrhizated and mycorrhizated seedlings with NaCl stress (0, 100, 200, 300 mmol·L-1) for 36 days, and then analyzed the mycorrhizal characteristics, growth, leaf injury symptoms, leaf electrolyte permeability, water content, and ion contents in roots, stems, and leaves. The results showed that the four ECMFs could establish a symbiotic system with Q. mongolica, and that root system of mycorrhizal seedlings was stronger than that of non-mycorrhizal seedlings. Under salt stress, the growth of Q. mongolica seedlings was inhibited, with the symptoms of scorched leaves. The damage to leaf plasma membrane and the degree of water loss were aggravated with the increases of salt stress. Under low salt stress (100 mmol·L-1), Q. mongolica preferentially accumulated Na+ in roots and stems. Under medium-high salt stress (200-300 mmol·L-1), roots became the primary organ for accumulating Na+. ECMF regulated ion balance in plant by increasing the Na+ level in roots and reducing the Na+ accumulation in stems and leaves, enhancing the absorption of K+ and Ca2+ to increase the K+/Na+ and Ca2+/Na+. The four ECMFs had different mitigation effects on salt poisoning of Q. mongolica. G. viscidus had the strongest effect, followed by S. leteus, while S. grevillei and B. edulis had relatively little effect.