Long-term Forest Research Articles

Global estimation of above-ground biomass from spaceborne C-band scatterometer observations aided by LiDAR metrics of vegetation structure

The backscattered power recorded by a spaceborne scatterometer operating at C-band is sensitive to land surface parameters and is operationally used by some global remote sensing services, e.g., to estimate soil moisture. The estimation of forest variables, in particular above-ground biomass (AGB), from scatterometer data instead was seldom explored. Given the availability of multi-decadal sets of scatterometer observations from space, it is of interest to address the contribution of C-band scatterometer data to the quantification of carbon stocks stored in forests even if the spatial resolution of spaceborne scatterometers is very coarse. In this paper, we investigated the prospects of AGB estimation using backscatter observations by the MetOp Advanced SCATterometer (ASCAT) with a spatial resolution of 0.25°. For this study, ASCAT observations acquired in 2010 were used to be contemporary with AGB datasets selected to benchmark the performance of the estimation. A Water Cloud Model that integrates two allometric equations derived from spaceborne LiDAR data reproduced the relationship between observations of radar backscatter as a function of AGB. Estimates of AGB from individual observations were then combined with a weighted average to reduce uncertainties. Finally, a correction was introduced to compensate for the offset introduced by sloped terrain and surfaces not covered by woody vegetation on the AGB estimate of a pixel. Uncertainties associated with the scatterometer observations, and the modelling framework were propagated to obtain per-pixel values of the standard deviation of an AGB estimate. The proposed method explains much of the variance in AGB estimates when compared to measurements from inventory data (R2 = 0.72) and generated unbiased estimates globally (bias: −3.3 Mg⋅ha−1). Nonetheless, the discrepancy between estimated and plot-based AGB values tended to increase for decreasing biomass level from 20% to 60% of the reference AGB level. A further assessment related to global stocks indicated that the value estimated from the scatterometer dataset (596 Pg, 95% of which 563 Pg stored in forest land) was in line with two published estimates based on forest inventory data only (571 Pg and 600 Pg, respectively). Despite the coarse spatial resolution, our results indicate that C-band scatterometer observations from space can contribute to the characterization of terrestrial biomass pools. The record of observations starting in the early 1990s may provide an unprecedented way to look at long-term forest dynamics as well as to constrain the strength of carbon-climate cycle feedback simulated by Earth System models.

Environmental changes in SW France during the Middle to Upper Paleolithic transition from the pollen analysis of an eastern North Atlantic deep-sea core

AbstractEvaluating synchronies between climate and cultural changes is a prerequisite for addressing the possible effect of environmental changes on human populations. Searching for synchronies during the Middle-Upper Paleolithic transition (ca. 48–36 ka) is hampered by the limits of radiocarbon dating techniques and the large chronological uncertainties affecting the archaeological and paleoclimatic records, as well by their low temporal resolution. Here, we present a high-resolution, pollen-based vegetation record from the Bay of Biscay, sea surface temperature changes, additional14C ages, and a new IRSL date on the fine-sediment fraction of Heinrich Stadial (HS) 6. The IRSL measurements give an age of ca. 54.0 ± 3.4 ka. The paleoclimatic results reveal a succession of rapid climatic changes during the Middle-Upper Paleolithic transition in SW France (i.e. D-O 12–8 and two distinct climatic phases during HS 4). Comparison of the new paleoclimatic record with chronologically well-constrained regional archaeological changes shows that no synchronies exist between cultural transitions and environmental changes. The disappearance of Neanderthals and the arrival ofHomo sapiensin SW France encompassed a long-term forest opening, suggesting thatHomo sapiensmay have progressively replaced Neanderthals from D-O 10 to HS 4 through competition for the same ecological niches.

A Tool for Long-Term Forest Stand Projections of Swedish Forests

The analysis of forest management strategies at landscape and regional levels forms a vital part of finding viable directions that will satisfy the many services expected of forests. This article describes the structure and content of a stand simulator, GAYA, which has been adapted to Swedish conditions. The main advantage of the GAYA implementation compared to other resources is that it generates a large number of management programmes within a limited time frame. This is valuable in cases where the management programmes appear as activities in linear programming (LP) problems. Two methods that are engaged in the projections, a climate change response function and a soil carbon model, are designed to complement other methods, offering transparency and computational effectiveness. GAYA is benchmarked against projections from the Heureka system for a large set of National Forest Inventory (NFI) plots. The long-term increment for the entire NFI set is smaller for GAYA compared with Heureka, which can be attributed to different approaches for modelling the establishment of new forests. The carbon pool belonging to living trees shows the same trend when correlated to standing volume. The soil carbon pool of GAYA increases with increased standing volume, while Heureka maintains the same amount over the 100-year projection period.

Turgor loss point predicts survival responses to experimental and natural drought in tropical tree seedlings.

Identifying key traits that can serve as proxies for species drought resistance is crucial for predicting and mitigating the effects of climate change in diverse plant communities. Turgor loss point (πtlp ) is a recently emerged trait that has been linked to species distributions across gradients of water availability. However, a direct relationship between πtlp and species ability to survive drought has yet to be established for woody species. Using a manipulative field experiment to quantify species drought resistance (i.e., their survival response to drought), combined with measurements of πtlp for 16 tree species, we show a negative relationship between πtlp and seedling drought resistance. Using long-term forest plot data, we also show that πtlp predicts seedling survival responses to a severe El Niño-related drought, although additional factors are clearly also important. Our study demonstrates that species with lower πtlp exhibit higher survival under both experimental and natural drought. These results provide a missing cornerstone in the assessment of the traits underlying drought resistance in woody species and strengthen πtlp as a proxy for evaluating which species will lose or win under projections of exacerbating drought regimes.

POTENSI TEGAKAN DI KPHL BATU SERAMPOK, PROVINSI LAMPUNG

Data and information regarding the potential of forest stands is very important in the preparation of Long-Term Forest Management Plan at Forest Management Unit. The purpose of the study was to analyze the potential of stands in the Protected Forest Management Unit Batu Serampok. Data and information were collected using a stratified systematic sampling with random start inventory method, then vegetation was analyzed to obtain an index of importance. The results showed a diversity of potential stands. The species that predominate in the seedling phase are clove (Syzygium aromaticum), because the commodity is easily grown and liked by the community. The species that has the highest importance in the sapling phase is bayur (Pterospermum sp.), This is because the species is included in the semi-intolerant classification and its distribution is quite easy. In the pole phase, the dominant species are bayur and mango (Mangifera indica). The dominance of bayur has decreased in the pole phase due to changes in environmental conditions, adaptability and the presence of other plants developed by the community. Mango also have a fairly dominant number, as well as other types of Multi Purpose Tree Species (MPTS) plants. Then at the tree level, the dominant species include bayur, jengkol (Archidendron pauciflorum), teak (Tectona grandis), gondang (Ficus variegata), candlenut (Aleurites moluccana) and petai (Parkia speciosa). In this phase there has been a balance between species of wood forest and MPTS. This happened because of the intervention of the HKm group in determining the types of plants to be developed. The preparation of the RPHJP document in Forest Management Unit should pay attention to the types of plants that are dominant and preferred by the community, especially in the planning part of forest land reforestation program.

How the Strength of Monsoon Winds Shape Forest Dynamics

Monitoring long-term forest dynamics can improve our understanding of how tree species change under varying environmental conditions over time. The Nanjenshan Nature Reserve, located in the southernmost part of Taiwan, is covered by natural tropical forest and affected by the northeast monsoon wind in the winter. To explore how monsoon wind shapes the structure of vegetation, we used the long-term data of the Lanjenchi plot (high wind exposure forest) and Nanjenshan plot I (low wind exposure forest) located in the Nanjenshan Nature Reserve. In these two plots, all free-standing trees with diameter at breast height (DBH) ≥ 1 cm were identified, measured, and mapped five times in thirty years (1989–2019). Temporal changes of tree abundance, dominance, recruitment, and mortality were calculated for all species. We recorded 9694 ± 3924 individual ha−1 belonging to 126 species in the high wind exposure forest and 4019 ± 1791 individual ha−1 belonging to 105 species in the low wind exposure forest in the latest census (census 5). From 1989 to 2019, stem density in the high wind exposure forests decreased (from 12,179 ± 6689 to 9694 ± 3924 individual ha−1), while stem density in the low wind exposure forests increased (from 3253 ± 1208 to 4019 ± 1791 individual ha−1). The stem density of the rare species, which survived only in the high wind exposure forest, decreased over time. However, the basal areas of these two forests barely changed during the study periods. Due to environmental conditions, the two forests have developed different forest structures in spaces and time. Species stem density in the high wind exposure forest and diversity could continually decrease and affect the maintenance of species diversity in the monsoon wind-shaped forest.

Long-Term Forest Conversion Affects Soil Stability and Humic Substances in Aggregate Fractions in Subtropical China

Soil aggregates are the basic structural components of soil, which are important factors that can predict erosion resistance. However, few researchers have investigated the effects of forest conversion on the stability of soil aggregates, particularly in subtropical forests. In this study, soils from various depths (0 to 30 cm) were collected from four forest types (transformed from broadleaved forests (BMF) to combined coniferous broadleaved (CBMF), Chinese fir (FF), and bamboo forests (BF)) to determine the impacts of forest conversion on the physical and chemical properties of soil, water-stable soil aggregates, and aggregate-associated humic substances. The results showed that forest conversion had no effects on the soil’s physical properties, or the humic substances in bulk soil, but had significant effects on soil aggregates. In addition, the conversion of broadleaved forest to Chinese fir forest increased the soil stability, and to bamboo forest, decreased the soil stability. Finally, the soil’s physicochemical properties were closely related to aggregate-associated humic substances. In summary, specific forest management measures should be applied to strengthen the positive impacts and reduce the negative impacts associated with forest conversion.

Fire Impacts on Recruitment Dynamics in a Seasonal Tropical Forest in Continental Southeast Asia

The effects of forest fires on tree recruitment dynamics in tropical forests is important for predicting forest dynamics and ecosystem function in Southeast Asia. To our knowledge, no studies have examined the effects of fire intensity on community-level recruitment patterns in tropical forests due to the rarity of long-term observation datasets in fire-impacted tropical forests and the difficulty of quantifying fire intensity. We addressed two questions: (1) is tree recruitment among species affected by fire intensity? and if so, (2) are there specific plant functional traits associated with these responses? We used data from a long-term forest dynamics plot at the Huai Kha Khaeng (HKK) Wildlife Sanctuary in Thailand. The HKK plot occurs in a strongly seasonal tropical environment and has experienced several fires since its establishment in 1994. We found 46 tree species (52% of the 89 species analysed) showed evidence of reduced recruitment rates with increasing fire intensities during the most recent fire in 2005. Tree species in this flammable landscape have various leaf and wood functional traits associated with fire. Spatial and temporal variability in fire activity may lead to alterations in long-term taxonomic and functional composition of the forest due to selection on fire-related traits.

Variation in Leaf Morphological Traits of European Beech and Norway Spruce Over Two Decades in Switzerland

Leaf morphological traits (LMTs) of forest trees have been observed to vary across space and species. However, long-term records of LMTs are scarce, due to a lack of measurements and systematic leaf archives. This leaves a large gap in our understanding of the temporal dynamics and drivers of LMT variations, which may help us understand tree acclimation strategies. In our study, we used long-term LMT measurements from foliar material collections of European beech (Fagus sylvatica) and Norway spruce (Picea abies), performed every second year from 1995 to 2019 on the same trees within the Swiss Long-term Forest Ecosystem Research Program LWF. The 11 study plots (6 beech, 4 spruce, and 1 mixed) are distributed along gradients of elevation (485–1,650 m a.s.l.), mean annual precipitation (935–2142 mm), and mean annual temperature (3.2–9.8°C). The investigated LMTs were (i) leaf or needle mass, (ii) leaf area or needle length, and (iii) leaf mass per area or needle mass per length. We combined this unique data set with plot variables and long-term data on potential temporal drivers of LMT variations, including meteorological and tree trait data. We used univariate linear regressions and linear mixed-effects models to identify the main spatial and temporal drivers of LMT variations, respectively. For beech LMTs, our temporal analysis revealed effects of mast year and crown defoliation, and legacy effects of vapor pressure deficit and temperature in summer and autumn of the preceding year, but no clear long-term trend was observed. In contrast, spruce LMTs were mainly driven by current-year spring conditions, and only needle mass per length showed a decreasing long-term trend over the study period. In temporal models, we observed that LMTs of both species were influenced by elevation and foliar nutrient concentrations, and this finding was partly confirmed by our spatial analyses. Our results demonstrate the importance of temporal analysis for determining less recognized drivers and legacy effects that influence LMTs, which are difficult to determine across space and species. The observed differences in the temporal drivers of beech and spruce LMTs suggest differences in the adaptation and acclimation potential of the two species.

Forest Transitions in the United States, France and Austria: dynamics of forest change and their socio- metabolic drivers

ABSTRACT Understanding the drivers of forest transitions is relevant to inform effective forest conservation. We investigate pathways of forest transitions in the United States (1920–2010), France (1850–2010), and Austria (1830–2010). By combining evidence from forest inventories with the forest model CRAFT, we first quantify how change in forest area (ΔA), maximum biomass density (ΔBdmax ), and actual biomass as fraction of maximum biomass (ΔFmax ) shaped forest dynamics. Second, to investigate the connections between forest change and societal resource use, or social metabolism, we quantify the importance of selected proximate and underlying socio-metabolic drivers. We find that agricultural intensification and reduced forest grazing correlated most with positive ΔA and ΔBdmax . By contrast, change in biomass imports or harvest did not explain forest change. Our findings highlight the importance of forest growth conditions in explaining long-term forest dynamics, and demonstrate the distinct ways in which resource use drove forest change.

Carbon Stabilization Pathways in Soil Aggregates During Long-Term Forest Succession: Implications from Δ13c Signatures

Carbon Stabilization Pathways in Soil Aggregates During Long-Term Forest Succession: Implications from Δ13c Signatures

Modeling Fire Hazards for the Maintenance of Long-Term Forest Inventory Plots in Alberta, Canada

Modeling Fire Hazards for the Maintenance of Long-Term Forest Inventory Plots in Alberta, Canada

Controls of contemporary (2001–2018) springtime waterflow dynamics in a Large, snowmelt-dominated basin in northeastern North America

The objective of this study was to characterise the primary forcing variables and system feedback responsible for daily waterflow dynamics within a large, international river system (Canada and USA) during 17 melt seasons from 2001 to 2018. An analysis based on extreme gradient boosting showed that daily waterflow in four subcatchments of the upper Saint John River (SJR, Wolastoq) basin during the 17 melt seasons was to a large measure controlled by the area’s seasonal warming associated with the springtime increase in regional incident global radiation and northeasterly advection of sensible and latent heat from southerly locations. Historically, seasonal surges in air temperature and cumulative snow degree-days were shown to contribute to roughly 60% of the control on subcatchment discharge by influencing the production and timing of snowmelt. Peak accumulation of snow on the ground provided the second most important control of discharge, accounting for about 15.6% of the overall control at a daily timescale. Cumulative short- and long-term forest cover losses in the four subcatchments provided some control, but at varying levels (i.e., 4.8–14.2%) dependent on the extent of total forest cover loss and other subcatchment traits. Convergent cross mapping confirmed the unidirectional, causal relationship between annual forest cover loss and daily discharge rates at the outlet of three of the four subcatchments. The strength of the annual-forest-cover-removal-to-daily-discharge signal within the four subcatchments varied, with the subcatchment with the least annual forest cover loss (<1%, over the 17 years), predictably displaying the weakest signal (p = 0.282). Forest cover removal was shown to increase springtime discharge for all subcatchments, albeit at different rates. This work provides a more comprehensive, mechanistic interpretation of daily snowmelt control of stream/river flow dynamics in northeastern North America.

Spatiotemporal Contribution of Participants in Patrolling Efforts from a Forest Station, Pu Hu Nature Reserve, Vietnam

Understanding the contributions of participants from management practices and those from the local community to protected areas (PAs) as nature reserves, is crucial for forest protection and resource conservation. Thus, empirical studies have usually investigated whether patrolling has significantly improved forest protection action. Many previous studies have exhaustively examined the contributions to forest protection by rangers or local persons, but there has been little research on the contribution of both sides to patrol efforts with separate consideration given to each. This paper explores insights into the patrol efforts in the Nam Tien forest station. The total number of patrollers, walking distances, and working days across years were significantly different between the ranger and local person patrol groups. There was a considerable variation in the number of patrollers (Z = 2.02; p &lt; 0.01), distance (Z = 2.45; p &lt; 0.01) and working days (Z = 2.37; p &lt; 0.01) between rangers and local persons related to monthly patrolling. For the traditional patrols in the various PAs, it is shown that, for long-term forest protection, local persons patrolling should be considered more, in order to achieve the sustainable conservation.

Long-Term Impact of Transhumance Pastoralism and Associated Disturbances in High-Altitude Forests of Indian Western Himalaya

The Himalayan Mountains are geodynamical important, featuring a wide climatic range with a rich diversity of flora, fauna, human communities, culture, and social set-up. In recent decades, due to constant anthropogenic pressure and considerable changes witnessed in the climate of the region, species of this region are threatened. Here, we assessed the impact of nomadic settlement and associated disturbances on plant species composition, diversity parameters, ecosystem properties, and fire incidence in high-altitude forests of Western Himalaya, India. Based on the distance between nomadic settlement location and forest, we classified forest as near nomadic settlement (NNS) or away nomadic settlement (ANS) forest types. We found a significant variation in plant species composition between forest types. Three species, namely, Sibbaldia cuneata, Poa annua, and Abies pindrow, contribute 25% of the cumulative variation in plant species composition. Studying live plants, we found a significant difference only for density, in which ANS had a higher average density than NNS. Considering dead plants, we found a significant difference in all nine plant-related parameters evaluated between sites. NNS had a higher value of all parameters evaluated, except for height, which was higher in ANS sites. ANS forest type show 1.3 times more average carbon stock (160.39 ± 59.03 MgCha−1; mean ± SD) than NNS forest type (120.40 ± 51.74 MgCha−1). We found a significant difference in plant diversity evaluated between forest types. ANS had higher values of Margalef and Fisher diversity but lower values of evenness. We found that NSS had significantly higher values of fire incidences, whereas ANS has a higher normalized differential vegetation index and enhanced vegetation index. Overall, our study showed that species composition, diversity, and fire incidence are strongly impacted due to nomadic settlements. These findings are paramount for designing appropriate livelihood options for indigenous communities and management policies of the long-term forest harvest to achieve global goals and the UN Decade on Ecosystem Restoration targets (2021–2030) to protect the sustainable development of forest mountainous regions.

Urbanization and Long-Term Forest Dynamics in a Metropolitan Region of Southern Europe (1936–2018)

Although peri-urban landscapes in Southern Europe still preserve a relatively high level of biodiversity in relict natural places, urban expansion is progressively consuming agricultural land and, in some cases, forest cover. This phenomenon has (direct and indirect) environmental implications, both positive and negative. The present study contributes to clarifying the intrinsic nexus between long-term urban expansion and forest dynamics in a representative Mediterranean city based on diachronic land-use maps. We discuss some counterintuitive results of urbanization as far as forest expansion, wildfire risk, and biodiversity conservation are concerned. Forest dynamics were investigated at two time intervals (1936–1974 and 1974–2018) representing distinctive socioeconomic contexts in the Rome metropolitan area in Central Italy. Additionally, the spatial relationship between forest cover and urban growth was evaluated using settlement density as a target variable. All over the study area, forest cover grew moderately over time (from 18.3% to 19.9% in the total landscape), and decreased along the urban gradient (i.e., with settlement density) more rapidly in 2018 than in 1936. The diversification of forest types (Shannon H index) was higher in areas with medium-density settlements, indicating a tendency towards more heterogeneous and mixed structures in rural and peri-urban woods that undergo rising human pressure. The dominance of a given forest type (Simpson’s D index) was higher at high settlement density areas. Evenness (Pielou’s J index) was the highest at low settlement density areas. The long-term assessment of land-use dynamics in metropolitan fringes enriched with a spatially explicit analysis of forest types may inform regional planning and environmental conservation, which could delineate appropriate strategies for sustainable land management in Southern European cities.

The competitive mechanism between post-abandonment Chinese fir plantations and rehabilitated natural secondary forest species under an in situ conservation policy

During the past 30 years, the global forest area has been subject to a continuous increase in planted forests and a decline in natural forests, raising significant concerns about biodiversity protection. Once these plantations are abandoned due to changes in conservation or forest management policies, can they recover to the same state as natural forests during secondary succession? The key ecological processes supporting the stable coexistence or competitive elimination mechanisms between post-abandonment plantations and natural secondary forest tree species are still poorly understood and may be the decisive ecological processes driving secondary forest restoration. A 12-ha long-term forest plot was established in an abandoned Chinese fir plantation that has been protected under an in situ protection policy for 40 years. In total, 66,317 individual trees were stem mapped and identified at the species level, and the spatial survival strategies and species coexistence mechanisms between Chinese fir and natural secondary forest tree species were investigated. The results showed that the spatial survival strategy of Chinese fir could effectively trade off a high conspecific density-dependent mortality rate of individuals during the early stage of secondary succession for the long-term survival of the whole population, which promoted its dominance during later stages of succession. By contrast, although the higher survival rate and larger intraspecific aggregation scale of natural secondary forest individuals favored their survival during initial colonization, this spatial survival strategy might occur at the cost of neglecting suitable habitats and the loss of competitive advantages at the later stage of succession. Regarding interspecific competition, the asymmetric competition process further ensured the advantages of Chinese fir in individual size growth and increased the competitive advantage of Chinese fir over natural secondary forest tree species by exclusion through interspecific competition during the later secondary succession stage. Our results suggest that implementing a forest recovery program or an in situ protection policy based on post-abandonment monoculture plantations may involve great uncertainty about whether the goal can be achieved. Specifically, although this strategy could quickly increase forest coverage and restore the forest landscape, it may also create difficulties in restoring the forest to its original state.

Tree recruitment is determined by stand structure and shade tolerance with uncertain role of climate and water relations.

Tree regeneration is a key process for long‐term forest dynamics, determining changes in species composition and shaping successional trajectories. While tree regeneration is a highly stochastic process, tree regeneration studies often cover narrow environmental gradients only, focusing on specific forest types or species in distinct regions. Thus, the larger‐scale effects of temperature, water availability, and stand structure on tree regeneration are poorly understood.We investigated these effects in respect of tree recruitment (in‐growth) along wide environmental gradients using forest inventory data from Flanders (Belgium), northwestern Germany, and Switzerland covering more than 40 tree species. We employed generalized linear mixed models to capture the abundance of tree recruitment in response to basal area, stem density, shade casting ability of a forest stand as well as site‐specific degree‐day sum (temperature), water balance, and plant‐available water holding capacity. We grouped tree species to facilitate comparisons between species with different levels of tolerance to shade and drought.Basal area and shade casting ability of the overstory had generally a negative impact on tree recruitment, but the effects differed between levels of shade tolerance of tree recruitment in all study regions. Recruitment rates of very shade‐tolerant species were positively affected by shade casting ability. Stem density and summer warmth (degree‐day sum) had similar effects on all tree species and successional strategies. Water‐related variables revealed a high degree of uncertainty and did not allow for general conclusions. All variables had similar effects independent of the varying diameter thresholds for tree recruitment in the different data sets.Synthesis: Shade tolerance and stand structure are the main drivers of tree recruitment along wide environmental gradients in temperate forests. Higher temperature generally increases tree recruitment rates, but the role of water relations and drought tolerance remains uncertain for tree recruitment on cross‐regional scales.

Age-Based Survival Analysis of Coniferous and Broad-Leaved Trees: A Case Study of Preserved Forests in Northern Japan

Scientifically sound methods are essential to estimate the survival of trees, as they can substantially support sustainable management of natural forest resources. Tree mortality assessments have mainly been based on forest inventories and are mostly limited to planted forests; few studies have conducted age-based survival analyses in natural forests. We performed survival analyses of individual tree populations in natural forest stands to evaluate differences in the survival of two coniferous species (Abies sachalinensis (F. Schmidt) Mast. and Picea jezoensis var. microsperma) and all broad-leaved species. We used tree rings and census data from four preserved permanent plots in pan-mixed and sub-boreal natural forests obtained over 30 years (1989–2019). All living trees (diameter at breast height ≥ 5 cm in 1989) were targeted to identify tree ages using a Resistograph. Periodical tree age data, for a 10-year age class, were obtained during three consecutive observation periods. Mortality and recruitment changes were recorded to analyze multi-temporal age distributions and mean lifetimes. Non-parametric survival analyses revealed a multi-modal age distribution and exponential shapes. There were no significant differences among survival probabilities of species in different periods, except for broad-leaved species, which had longer mean lifetimes in each period than coniferous species. The estimated practical mean lifetime and diameter at breast height values of each coniferous and broad-leaved tree can be applied as an early identification system for trees likely to die to facilitate the Stand-based Silvicultural Management System of the University of Tokyo Hokkaido Forest. However, the survival probabilities estimated in this study should be used carefully in long-term forest dynamic predictions because the analysis did not include the effects of catastrophic disturbances, which might significantly influence forests. The mortality patterns and survival probabilities reported in this study are valuable for understanding the stand dynamics of natural forests associated with the mortality of individual tree populations.

ASSESSMENT OF THE STATE AND RESTORATION OF BIOLOGICAL RESOURCES OF SCOTS PINE (PINUS SILVESTRIS L.) IN THE SOUTH OF THE CENTRAL RUSSIAN UPLAND

The paper deals with an assessment of the current state and prospects for the creation of artificial forest plantations based on Pinus silvestris L. to increase the bio resource potential of the south of the Central Russian Upland. There have been tested and methodically substantiated various methods of creating long-term forest plantations based on Pinus silvestris L. by improving the methods of sowing seeds. Evaluation of the effectiveness of various methods of sowing pine has shown that more guaranteed and uniform seedlings and further development of seedlings provide sowing with cones. Having an equal number of seed holes when sowing with seeds and cones, it can be stated that the number of holes in which seedlings appeared during sowing with cones is 56.8% higher, the survival rate of seedlings is 34.6% higher, the number of seedlings is 25% higher, and the number plants per hole – by 50%. Sowing with cones is economically more profitable-no need to engage in costly threshing of seeds; cones are easier to plant during mass plantings in the process of laying artificial forest plantations; cones have a high hygroscopicity, the seeds are constantly in a moist state and germinate well, regardless of the conditions of soil and air moisture.