Deciduous Coniferous Forest Research Articles

Successional changes in aphyllophorales macromycetes at different stages of coniferous xylolysis

The state of modern protective plantations in coniferous-deciduous forests of the Non-Chernozem zone is characterized by great heterogeneity. Currently, both protective forest plantations and protective tree plantations are managed by an extensive method, often without taking into account biological relationships in the agrophytocenosis. Successional changes in Aphyllophorales macromycetes (AFMM) at different stages of xylolysis of large tree debris represent a complex biochemical process. The limiting conditions for the active growth of fungal mycelium inside wood include light, access to moisture and air, violations in water transport. As mycogenic xylolysis develops, there is an increase in the biodiversity of AFMM species, which reaches a maximum at stage III–IV. On a large data set of 332 model trees and 3,543 basidiomes of xylotrophic basidiomycetes, the presence of correlations between the settlement on the substrate of various ecological groups of AFMM involved in xylolysis was established. It has also been shown that the fruit bodies of fungi are actively formed under conditions of abiotic stress and their number increases in subsequent seasons. When using AFMM as indicators of the xylolysis stage of coniferous species, it is necessary to take into account that the development of mycelium depends on the structural features of the wood. The course of mycelium development in the trunk cross-section is associated with both the action of external environmental factors and interference processes between species. At the same time, the frequency of basidioma formation and their age are of great importance in field identification.

CARBON SEQUESTRATION IN A KARST MIRE OF THE MORDOVIAN RESERVE DURING THE LATE HOLOCENE

The article presents the results of the study of carbon accumulation over the past 3000 years in the Stol-bovoye karst mire located within the Smidovich Mordovian State Nature Reserve on the southern border of the coniferous-deciduous forests of the East European Plain. Minerothrophic (sedge, wood-sedge, grass) and mesotrophic (Sphagnum, grass-Sphagnum, sedge-Sphagnum, cotton grass) types of peat are present in the peat deposits of the Stolbovoye mire. The mire is at the mesotrophic stage of development. The content of organic carbon varies from 37,2 to 53,4% (49,7% on average). The nitrogen content in peat shows significantly higher variations along the core compared to organic carbon, i. e. from 1,1 to 2,6% (the average value is 1,9%). The total carbon pool in the Stolbovoye mire is about 6,7 kg/m2. The data obtained showed that a fast-growing peatland is capable to sequester large amounts of atmospheric carbon. The carbon accumulation rate in the studied peatland varies from 32,0 to 158,4 g C/m2/yr, with an average of 68,9 g C/m2/yr, which is significantly higher than the average carbon accumulation rates in different types of peatlands during the Holocene. A relationship between carbon accumulation rate and climatic changes over the past 3000 years was not revealed. A significant increase in the rate of carbon accumulation at a depth of 60 cm (480 cal. years BP) could be associated with the high productivity of vascular plants even at higher levels of mineralization/humification of their residues.

The Impacts of Phenological Stages within the Annual Cycle on Mapping Forest Stock Volume Using Multi-Band Dual-Polarization SAR Images in Boreal Forests

SAR images with two polarizations show strong potential for mapping forest stock volume (FSV) combined with limited samples. However, accurately mapping FSV still presents challenges in selecting the optimal acquisition date to obtain the SAR images during specific phenological stages within the annual forest cycle (growth and dormant stages). To clarify the impacts of phenological stages within the annual cycle on FSV mapping, SAR images with various polarization models and bands (Sentinel-1(S), GaoFen-3(GF-3 (G)) and ALOS-2(A)) were acquired within the growth and dormant stages of an annual cycle in a boreal evergreen coniferous forest (Chinese pine) and a deciduous coniferous forest (Larch). Subsequently, single-band (G, S, and A) and multi-band combined alternative variable sets (A + G, A + S, S + G, and A + S + G) were extracted within the same stage, respectively. Finally, the forward selection approach was utilized in conjunction with four different models (MLR, KNN, RF, and SVR) to obtain the most suitable variable sets and generate FSV mapping. The results demonstrated a strong correlation between the intensity of backscattering coefficients and the phenological stages of the forest. Within the dormant stage, there was a significant decrease in the gaps of backscattering coefficients obtained from the same polarization compared to those within the growth stage. Furthermore, the results also revealed that more signals from inside the canopy could be detected during the dormant stage in both evergreen coniferous forests and deciduous coniferous forests. Subsequently, the accuracy in mapping FSV obtained from single-band SAR images within the dormant stage are slightly higher than that within the growth stage, and the accuracy was still significantly affected by both overestimation and underestimation. Moreover, the combined effects of different bands significantly improve the reliability of mapped FSV. The rRMSE values in four multi-band combinations ranged from 22.37% to 29.40% for Chinese pine forests and from 21.27% to 34.38% for Larch forests, and the optimal result was observed from combinations of A + S + G acquired within the dormant stage. It is confirmed that SAR signal and their sensitivity to FSV depends on the stages of forest annual growth cycle. In comparison to the growth period, dual-polarization SAR data acquired during the dormant stage is more suitable for estimating FSV in boreal forests.

High-precision estimation of plant alpha diversity in different ecosystems based on Sentinel-2 data

At present, the accuracy of remote sensing estimation models of plant alpha diversity is generally low, and high-precision estimation models in deciduous broadleaved forest (DBF), deciduous coniferous forest (DCF) and evergreen coniferous forest (ECF) are still lacking. The main purpose of this study is to construct high-precision remote sensing models for plant alpha diversity in multiple ecosystems at global scale. Normalized Difference Vegetation Index (NDVI) were derived from Sentinel-2 data. NDVI and NDVI based spectral diversity/heterogeneity indices were selected as predictive variables, and alpha diversity indices were selected as response variables. Simple linear regression (SLR), partial linear regression (PLSR), and random forest (RF) models were used to evaluate the predictive ability of the predictive variables against the response variables under six ecosystems (evergreen broadleaved forest (EBF), DBF, ECF, DCF, shrub, and grassland), and to compare the estimated robustness of various spectral diversity indices. In terms of prediction accuracy, the SLR models were the worst, and the PLSR model were average. RF performed best, outperforming most current models. Especially in DBF, ECF, shrub and grassland, the determination coefficient R2 of RF models can be as high as 0.9. In terms of the prediction of α-diversity, the prediction effect of species richness was better than that of Shannon index, Simpson index and Pielou index. The higher the vegetation complexity, the more accurate the assessment of vegetation α-diversity tends to be, especially in DBF, shrub and grassland. According to the importance of predictive variables and model stability evaluation results, NDVI, standard deviation of NDVI (SD), and NDVI derived Shannon’s diversity index (Sha), Cumulative Residual Entropy (CRE), Pielou’s evenness index (Pie), Hill’s numbers (Hill), Berger-Parker’s diversity index (Ber), Parametric Rao’s index of quadratic entropy(paRao) are all powerful indicators for predicting plant alpha diversity. Among them, the prediction performance of NDVI and SD is better. This study is not only an exploration of the practicability of R package “rasterdiv”, but also an attempt to construct high-precision remote sensing estimation models of plant alpha diversity at global scale.

Assessment of the Biomass of Coniferous–Deciduous Forest by the Example of the Chashnikovo Training and Experimental Soil Ecological Center of Moscow State University

Assessment of the Biomass of Coniferous–Deciduous Forest by the Example of the Chashnikovo Training and Experimental Soil Ecological Center of Moscow State University

CONIFEROUS LEAF-BEARING FOREST BIOMASS ASSESSMENT BY THE EXAMPLE OF THE EDUCATIONAL AND EXPERIMENTAL SOIL AND ECOLOGICAL CENTER OF LOMONOSOV MOSCOW STATE UNIVERSITY “CHASHNIKOVO”

The aim of the work was to assess the contribution of the following components - biomass and mortmass of tree stands, undergrowth, living ground cover, and forest litter - to the total organic matter’s pool of plant community. The object of the study was a territory of coniferous-deciduous forest located in Solnechnogorsk City District of the Moscow region, in which five permanent sample trial plots of 50·50 m were allocated. The greatest contribution to the total organic matter mass of studied plant communities was made by forest stand perennial parts (up to 87%) and forest stand mortmass (up to 14%), and phytomass of deciduous trees in stand containing 32 to 98%, which was connected with incompleteness of forest restoration succession process. The contribution of forest litter was no more than 3%; litter deposit was low (0,18-1,21 kg·m-2), which is not typical for spruce forests, as is the fact that all litter is of the destructive type. Living ground cover in terms of floristic composition and ecological-coenotic structure was typical for the subzone of coniferous-deciduous forests; its contribution to the overall productivity of forest biogeocenosis was insignificant. The spatial intrabiogeocenotic structure of litter reserves and living ground cover biomass distribution was disturbed compared to typical spruce forests due to the high proportion of deciduous species in the forest stand. Deciduous species inclusion in the tree tier, typical of the final stage of formation of a secondary coniferous forest during succession, caused a slight increase in the intensity of the biological cycle, which was indicated in this case by a decrease in the supply of litter and a simplification of their structure. Since the biomass and mortmass of tree stand make the greatest contribution to the sequestration of carbon by forest biogeocenoses, it is these components that require the most detailed assessment during monitoring observations, the purpose of which is to assess the carbon reserves of terrestrial ecosystems.

Influence of Clear Felling on СО2 Emission from Surface of Podzolic Soil of Coniferous–Deciduous Forest (Middle Taiga, Komi Republic)

Influence of Clear Felling on СО2 Emission from Surface of Podzolic Soil of Coniferous–Deciduous Forest (Middle Taiga, Komi Republic)

Association between Soil Physicochemical Properties and Bacterial Community Structure in Diverse Forest Ecosystems.

Although the importance of the soil bacterial community for ecosystem functions has long been recognized, there is still a limited understanding of the associations between its community composition, structure, co-occurrence patterns, and soil physicochemical properties. The objectives of the present study were to explore the association between soil physicochemical properties and the composition, diversity, co-occurrence network topological features, and assembly mechanisms of the soil bacterial community. Four typical forest types from Liziping Nature Reserve, representing evergreen coniferous forest, deciduous coniferous forest, mixed conifer-broadleaf forest, and its secondary forest, were selected for this study. The soil bacterial community was analyzed using Illumina MiSeq sequencing of 16S rRNA genes. Nonmetric multidimensional scaling was used to illustrate the clustering of different samples based on Bray-Curtis distances. The associations between soil physicochemical properties and bacterial community structure were analyzed using the Mantel test. The interactions among bacterial taxa were visualized with a co-occurrence network, and the community assembly processes were quantified using the Beta Nearest Taxon Index (Beta-NTI). The dominant bacterial phyla across all forest soils were Proteobacteria (45.17%), Acidobacteria (21.73%), Actinobacteria (8.75%), and Chloroflexi (5.06%). Chao1 estimator of richness, observed ASVs, faith-phylogenetic diversity (faith-PD) index, and community composition were distinguishing features of the examined four forest types. The first two principal components of redundancy analysis explained 41.33% of the variation in the soil bacterial community, with total soil organic carbon, soil moisture, pH, total nitrogen, carbon/nitrogen (C/N), carbon/phosphorous (C/P), and nitrogen/phosphorous (N/P) being the main soil physicochemical properties shaping soil bacterial communities. The co-occurrence network structure in the mixed forest was more complex compared to that in pure forests. The Beta-NTI indicated that the bacterial community assembly of the four examined forest types was collaboratively influenced by deterministic and stochastic ecological processes.

Carbon Allocation to Leaves and Its Controlling Factors and Impacts on Gross Primary Productivity in Forest Ecosystems of Northeast China

Carbon allocation in forest ecosystems is essential for the optimization of growth. However, remote-sensing-based research on the estimation of carbon allocation in forests is inadequate. This article considers forests in northeastern China as the research area and uses leaf area index (LAI) data combined with random forest and structural equation modelling methods to study the spatiotemporal distribution characteristics and driving factors of carbon allocation to leaves (ΔLAI) in deciduous broad-leaved forests (DBF), deciduous coniferous forests (DNF), and mixed forests (MF) during the green-up period (GUP) at a monthly scale during April, May, June, and July from 2001 to 2021, and clarifies the impact of leaf carbon allocation on gross primary productivity (GPP). The ΔLAI was the highest in DBF in April and in DNF and MF in May. The ΔLAI in April with an increasing trend year by year in DBF and MF, and the ΔLAI in May with an increasing trend in DNF. Among all the direct and indirect relationships that affect ΔLAI, temperature (TEM) has the highest path coefficient for DBF’s ΔLAI in April (−1.213) and the start of the season (SOS) has the highest path coefficient for DNF (−1.186) and MF (0.815). ΔLAI in the GUP has a significant positive impact on the GPP. In the MF, the higher ΔLAI in May was most conducive to an increase in GPP. During the critical period, that is April and May, carbon allocation to leaves effectively improves the carbon sequestration capacity of forestland. This information is of great value for the development and validation of terrestrial ecosystem models.

Geographical distribution and potential distribution prediction of thirteen species of Citrus L. in China.

Using DIVA-GIS software to study the spatial accumulation of Citrus species, an important economic crop in China. Draw the distribution maps of Citrus to concerning altitude and vegetation, and use DIVA-GIS' Bioclim ecological model and maximum information entropy model Maxent software to estimate the potential distribution areas of various Citrus species. The results show that the Citrus genus is located in the south of Qinling Mountains, mainly in the southwest of China and the coast of southeastern China. Sichuan and Chongqing are the most densely distributed regions of Citrus. The distribution of Citrus is closely related to the vegetation type and altitude. The vegetation types in the distribution area is evergreen broad-leaved forest, evergreen shrub, deciduous broad-leaved forest, mixed-leaf forest coverage area, deciduous coniferous forest, farmland, trees, other vegetation coverage, and evergreen coniferous forest. The current potential distribution area of Citrus is mainly in Guizhou, Hubei, Hunan, Guangdong, Guangxi, Yunnan,Sichuan, Chongqing, and other provinces and municipalities and their borders, while the potential distribution area in the future moves northward and enter Henan and southern Gansu. At the same time, climate warming changes the distribution of suitable areas of Citrus, which makes the suitable areas of C. sinensis Osbeck, C. reticulata Blanco, and other crops greatly increased. Planning the planting area will effectively improve the yield and quality in the future. Planning presents new challenges.

Siberian species on the steppe stations of the northwestern exclave of the meadow steppe

Climate warming has revived interest in the problem of species migration, changing vegetation boundaries. “Oka flora” in the Prioksko-Terrasny Nature Reserve is an isolated fragment of steppe communities in the zone of coniferous-deciduous forests. Its peculiarity is the significant participation of Siberian and Caucasian species. According to the results of long-term observations (25 years), the participation of Siberian species in steppe test sites was evaluated. In the steppe communities of the reserve, a relic floristic core is isolated, which includes species of glacial time (Carex obtusata, Draba sibirica, etc.) and species of warm Atlantic Time (Melica picta). The main part species in steppe test sites are typical steppe or meadow-steppe species, identical to the zonal meadow steppes. Modern research is devoted to identifying the features of biotopes of steppe communities. It has been established that steppe biotopes are the driest and warmest in the reserve. In recent years, there has been an expansion of the area of dense-grain cereals. Observations suggest that the ecosystem is capable of holding a pool of many species for a long time, although not all species manifest themselves in conditions of changing climatic trends. Herbaceous vegetation, depending on the hydrothermal conditions of the upper soil horizons, is the most mobile.

Distance to a River Modifies Climate Legacy on Vegetation Growth in a Boreal Riparian Forest

Inter-annual variability in growing season temperature and precipitation, together with snow coverage duration, determine vegetation growth in boreal ecosystems. However, little is known about the impact of concurrent and antecedent climate, particularly snow cover duration, on vegetation growth in a boreal riparian forest. Additionally, significant uncertainty exists regarding whether the distance to a river (as a proxy of groundwater availability) further modifies these climatic legacy effects on vegetation growth. To fill this knowledge gap, we quantified the responses of different vegetation types (shrub, deciduous coniferous and broadleaf forests) to concurrent and antecedent climate variables in a boreal riparian forest, and further determined the magnitude and duration of climate legacies in relation to distance to a river, using MODIS-derived NDVI time series with gridded climate data from 2001 to 2020. Results showed that higher temperature and precipitation and longer snow cover duration increased vegetation growth. For deciduous coniferous forests and broadleaf forests, the duration of temperature legacy was about one year, precipitation legacy about two years and snow cover duration legacy was 3 to 4 years. Further, distance to a river modified the concurrent and antecedent temperature and snow cover duration legacy effects on vegetation growth, but not that of precipitation. Specifically, temperature and snow cover duration legacies were shorter at the sites near a river compared to sites at greater distance to a river. Our research highlights the importance of snow cover duration on vegetation growth and that closeness to a river can buffer adverse climate impacts by shortening the strength and duration of climate legacies in a boreal riparian forest.

Carbon budget of different forests in China estimated by an individual-based model and remote sensing.

Forests play a key role in the regional or global carbon cycle. Determining the forest carbon budget is of great significance for estimating regional carbon budgets and formulating forest management policies to cope with climate change. However, the carbon budget of Chinese different forests and their relative contributions are not completely clear so far. We evaluated the carbon budget of different forests from 1981 to 2020 in China through combining model with remote sensing observation. In addition, we also determined the relative contribution of carbon budget of each forest type to all forests in China. Eight forest types were studied: evergreen coniferous forest (ECF), deciduous coniferous forest (DCF), coniferous and broad-leaved mixed forest (CBF), deciduous broad-leaved forest (DBF), evergreen broad-leaved forest (EBF), evergreen deciduous broad-leaved mixed forest (EDBF), seasonal rain forest (SRF), and rain forest (RF). The results indicated that the Chinese forests were mainly carbon sink from 1981 to 2020, particularly the annual average carbon budget of forest from 2011 to 2020 was 0.191 PgC·a-1. Spatially, the forests' carbon budget demonstrated obvious regional differences, gradually decreasing from Southeast China to Northwest China. The relative contributions of carbon budget in different forests to all forests in China were different. During 2011-2020, the ECF forests contributed the most carbon budget (34.45%), followed by DBF forests (25.89%), EBF forests (24.82%), EDBF forests (13.10%), RF forests (2.23%), SRF forests (3.14%) and CBF forests (1.14%). However, the DCF forests were found mainly as carbon source. These results contribute to our understanding of regional carbon budget of forests.

USE OF PHYTO-INDICATION METHODS IN ASSESSMENT OF RELATIONSHIP OF NITROGEN CONTENT IN PLANTS WITH THEIR GROWING CONDITIONS (ON THE EXAMPLE OF FORESTS IN THE SOUTHERN MOSCOW REGION)

The relationship of the chemical composition of plants with conditions of their growth and their contribution to soil nitrogen during dying is revealed. The study was based on the materials of geobotanical relevés of 15 forest plots in the subzone of coniferous-deciduous forests in the south of the Moscow Region. Two methods of phytoindication were used. The type of habitat conditions was determined according to the Vorobyov-Pogrebnyak’s indicator species. The point values of soil nitrogen richness were calculated according to the Tsyganov’s scale. The nitrogen content in plant organs, samples of forest litter and soil was determined using gas chromatography. The analysis of the data showed a correlation between the types of forest vegetation conditions and the points on the Tsyganov’s nitrogen richness scale for the conditions of the southern Moscow Region. The nitrogen content in the forest litter has a high reliable relationship with the types of habitat conditions. It is shown that plants from the habitats which are richer in nitrogen according to the Tsyganov’s nitrogen richness scale have a higher nitrogen content in leaves, stems and rhizomes than plants growing in poorer soil conditions. The conducted study has shown the validity of using phytoindication scales for the assessment of soil conditions.

Unraveling Effect of Snow Cover on Spring Vegetation Phenology across Different Vegetation Types in Northeast China

Snow cover has significantly changed due to global warming in recent decades, causing large changes in the vegetation ecosystem. However, the impact of snow cover changes on the spring phenology of different vegetation types in Northeast China remains unclear. In this study, we investigated the response of the start of the growing season (SOS) to different snow cover indicators using partial correlation analysis and stepwise regression analysis in Northeast China from 1982 to 2015 based on multiple remote sensing datasets. Furthermore, we revealed the underlying mechanisms using a structural equation model. The results show that decreased snow cover days (SCD) and an advanced snow cover end date (SCED) led to an advanced SOS in forests. Conversely, an increased SCD and a delayed SCED led to an advanced SOS in grasslands. The trends of SCD and SCED did not exhibit significant changes in rainfed cropland. The maximum snow water equivalent (SWEmax) increased in most areas. However, the proportion of the correlation between SWEmax and SOS was small. The impact of snow cover changes on the SOS varied across different vegetation types. Snow cover indicators mainly exhibited positive correlations with the SOS of forests, including deciduous broadleaf forests and deciduous coniferous forests, with positive and negative correlations of 18.61% and 2.58%, respectively. However, snow cover indicators mainly exhibited negative correlations in the SOS of grasslands and rainfed croplands, exhibiting positive and negative correlations of 4.87% and 13.06%, respectively. Snow cover impacted the SOS through the “temperature effect” in deciduous broadleaf forests, deciduous coniferous forests, and rainfed croplands, while it affected SOS through the “moisture effect” in grasslands. These results provide an enhanced understanding of the differences in snow cover changes affecting SOS in different vegetation types under climate change in Northeast China.

A watershed-scale evapotranspiration model considering forest type, stand parameters, and climate factors

We developed a model to estimate evapotranspiration (ET) for temperate coniferous and broadleaf forests that considers stand structure (density and height) and meteorological data (precipitation, air temperature, solar radiation, and vapor pressure deficit) as input. We used globally available data from 65 publications, as well as 37 datasets from sources such as FLUXNET, that were collected mainly from temperate climates. The wet canopy evaporation (Ewet) submodel consisted of a nonlinear function to determine the ratio of interception loss to precipitation from stand density for coniferous forests or stand height for broadleaf forests. The parameters of the Ewet submodel were determined separately for rainfall and snowfall. The dry canopy evaporation (Edry) submodel consisted of a simplified Penman–Monteith equation, including a nonlinear function to determine the reference surface conductance from stand height. We tested the prediction ability of the model using data from three locations covered by evergreen coniferous (ET, 13–83 mm/month) and deciduous coniferous forests (24–104 mm/month) in central Japan, and a deciduous broadleaf forest (1–59 mm/month) in northern Wisconsin, USA, for a mixture of rain and snow. Our model reproduced seasonal ET patterns, with mean absolute errors of 10 ± 5, 12 ± 7, and 6 ± 9 mm/month for the evergreen coniferous, deciduous coniferous, and deciduous broadleaf forests, respectively. The model is applicable to ET estimation over watershed-scale areas with heterogeneous biotic (forest condition) and abiotic (meteorological) factors in landscapes with complex topography.

Особенности активного микогенного ксилолиза на сосне обыкновенной в зоне хвойно-широколиственных лесов

Микогенный ксилолиз на сосне обыкновенной ( Pinus sylvestris L . ) в хвойно-широколиственных лесах Нечерноземной зоны представляет собой сложный биохимический процесс, в котором участвуют четыре группы афиллофоровых грибов (АФГ). К лимитирующим условиям активного роста грибного мицелия внутри древесины относятся: свет, доступ к влаге и воздуху, нарушения в водном транспорте. По мере развития микогенного ксилолиза наблюдается рост биоразнообразия видов АФГ, которое достигает максимума на стадии III-IV. На большом массиве данных из 119 модельных деревьев и 3512 базидиом ксилотрофных базидиомицетов было показано, что плодовые тела грибов активно формируются в условиях абиотического стресса и в последующие сезоны число их увеличивается. Доминирующее положение в грибном комплексе на стадии II-III занимает целлюлозоразрушающий гриб Neoantrodia serialis [= Antrodia serialis ], а также лигнин-разрушаюшие грибы Stereum sanguinolentum и Trichaptum fuscoviolaceum. На стадии III-IV микогенного ксилолиза преобладает рост F. pinicola , стратегия освоения древесины которого похожа на N. serialis [= A. serialis ]. В процессе биологического разложения древесины сосны, разные виды АФГ эволюционировали по непохожим стратегиям освоения субстрата, формируя болезни по типу белой гнили (кольцевая коррозионная) или бурой гнили (сегментарная коррозионная). Исследования авторов продемонстрировали быстрое освоение субстрата S. sanguinolentum , с широким охватом большого объема ствола не только по периметру, но и в ядре ствола и далее в направлениях вверх и вниз внутри дерева по градиенту влаги и воздуха. Стратегия F. pinicola иная, и связана с приспособленностью к биохимии субстрата, поэтому он так широко распространен во многих местообитаниях и на разных частях ствола сосны обыкновенной. Mycogenic xylolysis in Scots pine ( Pinus sylvestris L.) in coniferous-deciduous forests of the Non-Chernozem zone is a complex biochemical process involving four groups of Aphyllophorales fungi (APF). The limiting conditions associated with the directed active growth of fungal mycelium inside the wood include illumination, access to moisture and air. With the development of mycogenic xylolysis, there is an increase in the biodiversity of AFG species, which reaches a maximum at stage III-IV. On a large data set of 119 model trees and 3512 basidiomes of xylotrophic basidiomycetes, it was shown that the fruit bodies of fungi are actively formed under abiotic stress and in subsequent seasons their number increases. The dominant position in the APF complex at stage II-III is occupied by the cellulose-destroying fungus Neoantrodia serialis [= Antrodia serialis ], as well as the lignin-destroying fungi Stereum sanguinolentum and Trichaptum fuscoviolaceum . At stage III-IV of mycogenic xylolysis, the growth of Fomitopsis pinicola prevails, the strategy of developing wood of which is similar to N. serialis [= A. serialis ]. In the process of biological decomposition of pine wood, different types of APF evolved according to different strategies for the development of the substrate, forming diseases of the type of white rot (annular corrosive) or brown rot (segmental corrosive). Our research has demonstrated the rapid development of the substrate of S. sanguinolentum , with a wide coverage of a large volume of the trunk not only along the perimeter, but also in the trunk core and further in the directions up and down inside the tree along the gradient of moisture and air. The strategy of Fomitopsis pinicola is different, and is related to the adaptation to the biochemistry of the substrate, which is why it is so widespread in many habitats and on different parts of the trunk of the scots pine.

THE INFLUENCE OF THE TYPE OF FOREST AND THE TYPE OF FOREST GROWING CONDITIONS ON THE STABILITY OF SPRUCE STANDS IN THE ZONE OF CONIFEROUS-DECIDUOUS FORESTS OF THE PERM KRAI

There has been a massive drying out of spruce plantations in recent years. Many versions about the cause of this phenomenon have been put forward by scientists. Despite the active study of the problem of drying out of spruce plantations around the world, a forest management system aimed at reducing the damage from drying out has not been developed yet. Important silvicultural indicators of plantations that can affect their stability are the type of forest growing conditions and the type of forest. The purpose of the study was to establish the influence of the type of forest and the type of forest growing conditions on the resistance to drying out of spruce forests growing in the zone of coniferous-deciduous forests of the Perm Krai. The spruce forests of this territory were the objects of study. The sanitary condition of spruce forests growing in common types of forest growing conditions (B2, C2, C3) and forest types (green moss spruce and pine forest, wood sorrel spruce and pine forest, linden spruce and pine forest, grass spruce and pine forest) of the Perm Krai was determined. The weighted average scores values of the sanitary condition of the spruce forest of the surveyed forest plantations were distributed by forest types and types of forest growing conditions. Statistical indicators of the average weighted scores of the sanitary condition of spruce in different types of forests were obtained. A one-factor analysis of variance was carried out to compare the mean values. It was established that the type of forest and the type of forest growing conditions have an impact on the sanitary condition of spruce stands. The better the forest growing conditions, the more resistant the spruce trees are to drying out, on average. At the same time, soil moisture is more important than soil nutrient status.

Labile and Stable Fractions of Organic Carbon in a Soil Catena (the Central Forest Nature Reserve, Russia)

The composition of soil organic carbon (SOC) is an important soil quality indicator. We investigated the effect of site-specific soil-forming factors on plant debris and SOC properties along a soil catena with Retisols and Stagnosols in a mixed coniferous–deciduous forest. We examined sites at the summit and middle slope positions with relatively well-aerated soils and sites at footslope positions with waterlogged soils. The concentrations of labile and stable pools of SOC were determined using the method of three-stage chemodestruction. The degree of litter decomposition was calculated, and ash content was determined in the folic and histic soil horizons. The results of our study showed that SOC mostly accumulated in the forest litter and histic horizons of Stagnosols at the footslope positions. The forest litter, folic, and histic horizons were dominated by labile carbon. Equal concentrations of labile and stable carbon were typical of the mineral horizons. The location of the soil in the catena affects the partition and characteristics of SOC in umbric and albic soil horizons. SOC was found to be more stable in the soils at the footslope positions compared to the soils in other locations, because of the lower decomposition of plant remains. Larger stocks of organic carbon, including labile carbon, were restricted to the footslope catena positions.

Changes in a Parcel Structure of Liana-Broadleaved Forests in Primorsky Region Over 20 Years

The study of the parcel structure dynamics of the Primorsky region’s forests is necessary to identify the natural restoration patterns of a formation unique to the region - primary coniferous-broad-leaved forests. As a result of economic activity, these forests, saturated with relic elements, were replaced by secondary ones in most of the affected area. The studies were carried out in the catchment area of the Komarovka river (Southern Primorye, Ussuri region). The article presents the results of the parcel structure study in the broad-leaved-linden hazel with liana vegetation of the herb forest type, which is representative for the region and is also the most complex as far the derivative forests formation is concerned. The classical research method was used: a detailed description and mapping on a scale of 1 : 100 of all phytocoenosis levels was performed on a permanent trial plot (PTP), followed by a pairwise maps comparison and the parcels allocation. An analysis of the phytocoenosis transformation over 20 years of restorative succession has shown that the main silvicultural and inventory characteristics of the stand have changed insignificantly. In the forest stand’s composition, an almost complete dropping out of aspen and linden has occurred, the latter being one of the main species of the local ecosystems. At the same time, the positions of the underbrush and the tree species, characteristic of primary coniferous-deciduous forests, have both strengthened. Changes in the parcel structure indicate the successful restoration of the primary forest type: two secondary complementary (small) parcels disappeared in the phytocoenosis, one more has joined the six conditionally-indigenous ones; there also was a natural enlargement of conditionally indigenous parcels and the alignment of their boundaries. The high indicator role of the grass layer was properly reflected in the study.