Red Pine Research Articles

Quantitative Changes of Phenolic Compounds in Pine Twigs by Variety, Harvest Season, and Growing Region.

Three new phenolic compounds including pinosylvin 3-methoxy-5-O-β-D-glucoside (PMG), taxiresinol 4’-O-α-L-rhamnoside (TRR), and lariciresinol 4’-O-α-L-rhamnoside (LRR) were first isolated and identified from red pine (Pinus densiflora Sieb. et Zucc.) twigs, together with four known compounds, such as (+)-catechin (CC), dihydromyricetin (DHM), dihydroquercetin 3-O-β-D-glucoside (DHQG), and dihydroquercetin (DHQ). Additionally, the concentrations of seven phenolic compounds in pine twigs were measured by high-performance liquid chromatography based on cultivars, harvest seasons, and growing environments. Red and black pine twigs contain 379.33 and 308.83 mg/100 g of PMG as the predominant phenolics, respectively, and their contents were significantly higher in spring than in autumn. Red pine twigs contain higher amounts of three dihydroflavonols (DHM: 87.82, DHQG: 38.47, and DHQ: 68.07 mg/100 g) and two lignans (LRR: 15.63, TRR: 30.72 mg/100 g) than black pine twigs, except for higher (+)-CC level (21.88 mg/100 g) in black pine twigs. Two pine twigs had much higher flavonoid and lignan levels in the autumn than they had in the spring. Two pine twigs harvested in several different areas do not significantly differ in their phenolic compositions and contents. These results suggest that red pine twigs possessing phytochemical phenolics may be useful as potential sources for promoting human health.

Modeling Climate Effects on Site Productivity of Plantation Grown Jack Pine, Black Spruce, Red Pine, and White Spruce Using Annual/Seasonal Climate Values

Site index (SI) is a commonly used measure of forest site productivity and is affected by climate change. Therefore, climate effects on site productivity were analyzed and modeled for jack pine (Pinus banksiana Lamb.), black spruce (Picea mariana (Mill.) B.S.P.), red pine (Pinus resinosa Ait.), and white spruce (Picea glauca (Moench) Voss) plantations using annual/seasonal values of climate variables. Jack pine and black spruce trees were each sampled from 25 plantations (sites), and red pine and white spruce trees were sampled from 30 and 31 plantations, respectively, from across Ontario, Canada. Stem analysis data collected from 201 jack pine, 211 black spruce, 90 red pine, and 93 white spruce trees were used in this study. To analyze and model climatic effects on site productivity, parameters of the stand height models were expressed in terms of climate variables. A nonlinear mixed-effects modelling approach was applied to fit the stand height models. Climate effects on site productivity was evaluated by predicting stand heights in three areas (the central, eastern/southeastern, and western parts of Ontario) for the period 2021 to 2080 under three emissions trajectories (representative concentration pathways (RCP) 2.6, 4.5, and 8.5 watts m−2). Climate effects on site productivity depended on tree species and location. For jack pine, climate effects were positive and pronounced only in western Ontario under all emissions scenarios. The effects were negative and mild after breast height age (BHA) 50 in central Ontario for black spruce. Similarly, the effects were negative and more pronounced at all areas after BHA 35 for red pine. On the other hand, for white spruce the effects were negative and highly pronounced from a young age under all scenarios, mainly in the southeast. For all species except for jack pine, climate effects were more pronounced under RCP 8.5 than the other two scenarios.

Akdeniz iklim bölgesindeki alt yükselti orman ve çalılıklarında yangın sonrası hızlı ekolojik değerlendirme ile restorasyon önerilerinin geliştirilmesi: Datça-Bozburun Özel Çevre Koruma Bölgesi örneği

The Mediterranean Basin is a biogeography shaped by fires for millions of years. For the restoration of burned areas in the Mediterranean Basin, therefore, planning should increase resistance and resilience of plant communities to fire by considering adaptation strategies of plant species to fire. In this study, following the fire of 2021, affected approximately 12,500 hectares in Marmaris region, a rapid assessment method and post-fire restoration prescriptions were developed for the Datça-Bozburun Special Environmental Protection Area. By using EFFIS and Sentinel-2 satellite images, the burned area was determined and classified to fire severity with normalized burn ratio difference The regeneration potential of burned areas was revealed by counting the number of serotinous cones of Turkish red pine (Pinus brutia) and estimating potential coverage of maquis species in sampling areas based on stand type and burn severity levels. Open pine stands had the highest serotiny and high resprouting potential following maquis vegetation, while the young pine stands have the lowest level of serotiny. Considering results and slope degrees, six restoration prescriptions were developed for burned areas. While 6% of the burned area was recommended to be left unmanaged, natural regeneration + laying out branches with cones and natural regeneration with additional seeding, and artificial regeneration by planting saplings after terracing and tillaging were foreseen for the remaining areas. This simple and cost-effective methodology developed in this study is highly applicable to local practitioners and decision makers, as it can be carried out within two months following the fire.

Multi-model approach to integrate climate change impact on carbon sequestration potential of afforestation scenarios in Quebec, Canada

Afforestation of unproductive or currently non-forested territories can increase carbon land sinks and thus contribute to mitigate climate change. However, investments on large-scale afforestation could be risky because of the predicted effect of climate change on forest productivity of newly created plantations. The aim of this study was to assess the carbon sequestration and mitigation potential of afforestation scenarios with different species (Picea mariana, Picea glauca, Pinus banksiana, Pinus resinosa and Populus spp) on open woodlands and abandoned farmlands in the Province of Quebec (Canada) under different radiative forcing projections. We modelled carbon dynamics in these lands under three Representative Concentration Pathways projections (RCP 2.6, RCP 4.5, and RCP 8.5) over the 2021–2100 period. The forest gap model PICUS was used to model tree growth of afforested species as a function of the Representative Concentration Pathways 2.6, 4.5 and 8.5; these data were then used as input in the Carbon Budget Model – Canadian Forest Sector 3 to simulate the evolution of ecosystem carbon stocks and fluxes as a function of forest management and climate. Carbon transfer to harvested wood products, and carbon fluxes associated with product life cycles and substitution effects on markets, were also included in the analyses. Results showed that Pinus species responded more strongly to variations in radiative forcing than for the other simulated species. Overall, aboveground biomass was particularly altered by increased radiative forcing, which in turn reduced harvesting yield and transfers to wood processing and products. At the end of the simulation, despite the expected impacts of radiative forcing on ecosystems, afforestation scenarios on open woodlands with black spruce, white spruce, and jack pine can deliver carbon mitigation of 32% – 70% over the baseline scenario and 4% – 12% for red pine on abandoned farmlands and, hence, contribute to efforts to reduce GHG emissions, especially over the long term. Although climate change is expected to impact the growth of newly planted areas as part of afforestation efforts, the results of our study suggest that the choice of species to plant and the selected forest management strategy have a greater impact on carbon stocks than climate change itself. This study provides a better understanding of the dynamics of afforestation under climate change and whether investments in plantation can contribute to GHG reduction targets.

Carbon Sequestration Using Exotic Larches in Central Maine

The carbon sequestration potential of exotics might be considered as one of the several alternatives for forest adaptation to climate change. The results presented here demonstrate that exotic larches’ (Larix spp.) growth rates for both carbon accumulation and traditional forest products exceed those of both natural regeneration and other planted species when planted on a good site in Maine. Recent re-measurement of a species-site trial established in 1988 represents the 34th growing season. Species included Black Spruce (BS) (Picea mariana Mill.), European larch (EL) (Larix decidua Mill.), hybrid larch (HL) (L. x marschelensi), Japanese larch (JL) (L. kaempferi (Lam.) Carrière), Jack pine (JP) (Pinus banksiana Lamb.), Red pine (RP) (Pinus resinosa Ait.), Tamarack (TL) (L. larcinia (Du Roi) K. Koch), and White spruce (WS)(Picea glauca (Moench) Voss). All three of the exotic larches outgrew the other species. Hybrid larch had over nearly twice the merchantable volume (m3 ha−1) and over three times the sawlog volume (green tonnes ha−1) than Red pine. Hybrid larch had the highest growth rate at age 34, over 20 m3 per hectare per year (nearly 3.3 cords ac−1 year−1 or 6.8 tons−1 acre−1 year−1). The other two exotic larches are growing at over 19 m3 ha−1 year−1 (3 cords acre−1 year−1 or 6.4 tons acre−1 year−1). Converting these growth rates to accumulation of CO2eq over the 34-year period produces stunning contrasts compared to native species. Over the 34-year period, larch hybrids sequestered 2.4 times as much CO2eq as the untreated plots (444 vs. 186 tonnes−1 ha−1). We discuss practical implications for forest management and carbon policies.

Response of natural tree regeneration to climate adaptation treatments in Pinus resinosa-dominated forests

Uncertainty and emerging threats associated with climate change necessitate the development of new approaches for managing forest ecosystems. To address this need the Adaptive Silviculture for Climate Change (ASCC) Network was established to examine the efficacy of three climate adaptation strategies in important forest types across North America: 1) resistance to change by increasing overstory tree health through reduced inter-tree competition, 2) resilience by creating conditions that allow change within the natural range of variability while encouraging greater abundance of native species considered suitable for projected future climate, and 3) transition which involves actively facilitating systems to have a more adaptive response. The present study focused on the influence of Adaptive Silviculture for Climate Change treatments on natural regeneration in a Pinus resinosa Ait. (red pine)-dominated forest in northern Minnesota, USA. We aimed to answer the following research questions: 1) How do different climate adaptation strategies (resistance, resilience, and transition) influence natural regeneration relative to passive management? 2) Do impacts on the understory woody community, including trees and shrubs, differ among treatments in terms of abundance, composition, and diversity?Naturally regenerated trees and shrubs were sampled during the 5th growing season following Adaptive Silviculture for Climate Change treatment implementation (May-August 2019). The species composition of naturally regenerated trees differed among treatments as did adaptability, quantified as a composite index that integrated disturbance response and life history traits. The transition treatment resulted in greater capacity for adaptation to future conditions in the newly regenerated cohort. All treatments increased tree species diversity and richness relative to passive management, but the greatest woody species diversity occurred in the resilience treatment. This suggests a trade-off between maximizing woody species diversity (greatest in the resilience treatment) and adaptability (greatest in transition treatment). Overall, these results affirm the potential for using silviculture to increase tree diversity and adaptability through natural regeneration in anticipation of threats posed by changing climate in a major forest type, with results serving as a model for expectations in similar ecosystems.

Study on the suppression of pyrolytic gas flames in red pine wood by water mist

The suppression of forest fires has been one of the important research directions in the field of fire safety, fine water mist because of the advantages of easy access to materials, low price and no pollution to become one of the commonly used inhibitors to suppress forest fires, so previous research done for fine water mist suppression of forest fires, mostly for the macro level of fire suppression effectiveness and methodological research, for fine water mist and forest fire interaction mechanism research is less, this paper for the convenience of research, the In this paper, to facilitate the study of red pine wood as the research object, after high temperature pyrolysis analysis of pyrolysis gas components, the construction of fine water mist suppression of red pine wood pyrolysis gas flame Bunsen burner experimental system, study the effect of different additions of fine water mist on the laminar flame speed (SL) of red pine wood pyrolysis gas flame, and the use of chemkin software to study the mechanism of interaction between fine water mist and red pine wood pyrolysis gas flame, on the study of the interaction between fine water mist and red pine pyrolysis gas flames using chemkin software has some implications for the suppression of forest fires. In this paper, the pyrolysis gas products of red pine wood were firstly analysed by TG-DSC as well as GC/MS and found to consist mainly of H2, CO2, C2H4, CO, CH4, C2H6, C3H6 and C3H8, accounting for more than 98% of the gases. The Bunsen burner experimental system constructed for the suppression of red pine pyrolysis gas flames by fine water mist revealed that the flame height gradually increased with increasing fine water mist addition and the flame cone angle gradually decreased, indicating that the flame speed was gradually decreasing with increasing fine water mist addition. It was observed that the flame height did not change significantly at low equivalents as the amount of extinguishing agent added increased, indicating that the fine water mist had a weak pro-ignition effect on the red pine pyrolysis gas/air system. The influence of the gas content on the flame promotion effect of the fine water mist was investigated by chemkin software. It was found that the ratio of CO/H2 in the pyrolysis gas composition of red pine wood will determine the strength of the combustion promoting effect of the fine water mist in the interaction with the pyrolysis gas flame, the higher the ratio of CO/H2, the stronger the combustion promoting effect of the fine water mist in the interaction with the pyrolysis gas flame, and conversely the lower the ratio, the weaker the combustion promoting effect of the fine water mist in the interaction with the pyrolysis gas flame.

Experimental and modeling analysis of laminar flame speed over the pyrolytic gas from red pinewood

In combustion research, the laminar flame speed (SL) is an important basis for the study of fuel combustion and mechanism verification. A large number of studies have been done on various combustibles, mostly focusing on gas and liquid combustibles, but less on solid combustibles, and the SL of solid combustibles cannot be measured directly and effectively by conventional methods. This paper uses red pine wood as the object of study, analyses the pyrolysis gas components after high-temperature pyrolysis, and uses the Bunsen burner experimental system to study the SL of pyrolysis gas, and obtains the laminar flame speed (SL) of the gas-phase flame when burning red pine wood, which has certain guiding significance for the study of the laminar flame speed (SL) of solid combustibles. In this paper, firstly, the pyrolysis gas products of red pine wood were analyzed by TG-DSC as well as GC/MS, and it was found that the direct reaction was the most violent at 210°C–410 °C, and the reaction rate gradually levelled off after 410 °C. It was also found that the gas mainly consisted of H2, CO2, C2H4, CO, CH4, C2H6, C3H6 and C3H8, accounting for more than 98%, and with the pyrolysis Secondly, the laminar flame speed (SL) of the gas products was investigated using the Bunsen burner, and it was found that the laminar flame speed (SL) of the pyrolysis gases gradually increased with the increase of the pyrolysis temperature, with 15.7 cm-s−1, 32.94 cm-s−1 and 36.89 cm-s−1 for the pyrolysis gases at 350 °C, 450 °C and 550 °C, respectively Finally, numerical simulations were carried out to investigate the effects of initial temperature and altitude induced changes in air pressure and oxygen concentration on the laminar flame speed of the gas products, and it was found that the laminar flame speed of pyrolysis gases gradually increased with increasing initial temperature and decreased with increasing altitude. The effect of hydrocarbon gases on the SL-max of CH4 is essentially linear in the concentration range of 40%, while the effect of H2, CO and CO2 is essentially in the quadratic polynomial distribution.

Effects of pre-steaming treatment on high-temperature and low-humidity drying characteristics of super-heavy timber with boxed-heart of Korean red pine and Douglas-fir

This study aimed to investigate how pre-steaming affects the drying times, final moisture contents (final MCs), and prevention of checking during the high-temperature and low-humidity drying process of boxed-heartwood Korean red pine (Pinus densiflora S. et Z.) and Douglas-fir (Pseudotsuga menziesii) with 20 × 20 cm and with 30 × 30 cm cross sections. Although average final MCs of the larger cross sections were slightly higher than those of smaller cross sections, all were over-dried between 3.3% and 8.1% MC, compared to the in-use moisture content for outdoor building materials. All the pre-steamed samples were only slightly defected by surface checks of 5 mm or less in width. The sample timbers with the 20 × 20 cm cross-sectional size were slightly defected by internal checking, whereas those with the 30 × 30 cm cross-sectional size were severely defected. However, there was no clear impact of pre-steaming time on the prevention of internal checking.

Prediction of Wildfire Fuel Load for Pinus densiflora Stands in South Korea Based on the Forest-Growth Model

A prediction model was developed for the wildfire fuel load of Korean red pine (Pinus densiflora) stands with susceptibility to forest fire based on the forest-growth model. Furthermore, a time-series analysis was performed on the variation in forest-fire fuel load according to forest management. National Forest Inventory stand data of 1434 plots for P. densiflora stands were used, and the final forest-fire fuel load prediction model was developed using the Weibull function and mortality model. The fit index of the diameter distribution model ranged from 0.58 (0th percentile) to 0.96 (50th percentile), and that of the mortality model was 0.68. The prediction of the stand growth variation after 20 years based on the growth data of managed and unmanaged stands indicated a mean stand density of 1518 trees per ha for unmanaged stands, and 885 trees per ha for managed stands. Regarding the variation in the available canopy fuel load distribution, the predicted annual increase was approximately 0.7 ton/ha for unmanaged stands and approximately 0.5 ton/ha for managed stands. These findings will contribute to setting fuel management criteria to prevent forest fire spread while providing the quantitative data of the characteristics of stand growth variation and the predicted wildfire fuel load.

Identification of upregulated genes in Tricholoma matsutake mycorrhiza.

Many plant roots associate with fungi to form mycorrhizae; tree roots especially associate with ectomycorrhizal fungi, such as Tricholoma species. Tricholoma matsutake is an economically important fungus in Asian countries and usually inhabits forests primarily composed of Pinus densiflora (Japanese red pine). In this study, to understand the mycorrhizal association between T. matsutake and P. densiflora, genes specifically expressed in mycorrhiza compared with those expressed in mycelia and fruiting bodies were identified by RNA-seq. This revealed that genes for chromatin, proteasomes, signal transduction, pheromones, cell surface receptors, cytoskeleton, RNA processing and transporters from T. matsutake were highly expressed in mycorrhiza. It also identified 35 mycorrhiza-induced small secreted proteins (MiSSPs) that were highly expressed in mycorrhiza. Meanwhile, genes for proteases, defence-related proteins, cell-wall degradation, signal transduction, pinene synthesis, plant hormones and transporters from P. densiflora were highly expressed in mycorrhiza. These genes may be involved in mycorrhizal formation and maintenance. A MiSSP, 1460819, was highly expressed in mycorrhiza, and this expression was maintained for 24 months. These results provide insight into the mycorrhizal association between T. matsutake and P. densiflora.

Optimization of eco-friendly Pinus resinosa biochar-dodecanoic acid phase change composite for the cleaner environment

The use of waste materials in sustainable energy forms has gained a tremendous research focus, which has risen the trend of energy demand coupled with environmental concerns. Contemplating that, biochar material from organic waste has been considered as shape stabilizing materials for the organic phase change materials (PCMs) aiming for thermal energy storage (TES) applications. Pinus resinosa (PR) fruits have been pyrolyzed into biochar which has exhibited a highly porous and channel-like morphology with a surface area of 27.99 m2/g. Dodecanoic acid (DA) in 1:1, 2:1, 3:1, and 4:1 ratios have been incorporated into the PR biochar for the fabrication of shape-stabilized phase change composites (DAPR). The highest melting and solidification enthalpies are exhibited by the DAPR-4 composite, though the values are almost similar to the DAPR-3 composite. Therefore, 3:1 DA to PR biochar can be considered as the optimum ratio. The maximum encapsulation efficiency and ratio are calculated to be 32.53 % and 32.66 %, respectively while the highest melting enthalpy is obtained at 50.87 J/g. All the DAPR composites have demonstrated admirable leakage-proof performance at elevated temperatures along with the congruent thermal cycle resilience up to 100 cycles of heat charging and discharging, without any alteration in temperatures and enthalpies. The exceptional thermal and structural stabilities manifested by the DAPR samples are ascribed to the capillary action, surface functionality, and space confinement effects of the biochar.

Spatial responses of soil carbon stocks, total nitrogen, and microbial indices to post-wildfire in the Mediterranean red pine forest

Wildfire is a key ecological event that alters vegetation and soil quality attributes including biochemical attributes at spatial scale. This knowledge can provide insights into the development of better rehabilitation or restoration strategies that depend on the ecological dynamics of vegetation, fungi, and animals. The present study aimed to understand the causes and consequences of spatial variability of soil organic carbon, microbial biomass C concentrations, and soil quality indices as impacted by wildfire in a red pine forest. This study was conducted using kriging and inverse distance neighborhood similarity (IDW) interpolations methods. The carbon stocks were significantly (P = 0.002) higher in burned areas compared to those of unburned areas by 255% whereas microbial biomass carbon and microbial respiration were significantly (P < 0.0001 and P = 0.02) lower in burned areas by 66% and 90%, The Pearson's correlation analysis showed that carbon stocks were positively correlated with pH (0.61), total nitrogen (0.60) and ash quantity (0.41), but negatively correlated with microbial biomass carbon (−0.46) and nitrogen (−0.61), and microbial respiration (−0.48). The IDW interpolation method better-predicted pH, bulk density, and microbial biomass carbon and nitrogen compared to kriging interpolation, whereas the kriging interpolation method was better than IDW interpolation for the other studied soil properties. We concluded that pH, EC, SOC, C/N, MR, MBC/SOC, and MBC/MBN can be reliable indicators to monitor the effect of wildfire on forest soils. The wildfire event increased soil carbon stocks, TN, pH, and qCO2, but decreased MBC and MBN.

Korean Red Pine (Pinus densiflora) Bark Extract Attenuates Aβ-Induced Cognitive Impairment by Regulating Cholinergic Dysfunction and Neuroinflammation.

In this study, we investigated the anti-amnesic effect of Korean red pine (Pinus densiflora) bark extract (KRPBE) against amyloid beta1-42 (Aβ1-42)-induced neurotoxicity. We found that treatment with KRPBE improved the behavioral function in Aβ-induced mice, and also boosted the antioxidant system in mice by decreasing malondialdehyde (MDA) content, increasing superoxide dismutase (SOD) activities, and reducing glutathione (GSH) levels. In addition, KRPBE improved the cholinergic system by suppressing reduced acetylcholine (ACh) content while also activating acetylcholinesterase (AChE), regulating the expression of choline acetyltransferase (ChAT), postsynaptic density protein-95 (PSD-95), and synaptophysin. KRPBE also showed an ameliorating effect on cerebral mitochondrial deficit by regulating reactive oxygen species (ROS), mitochondrial membrane potential (MMP) and ATP levels. Moreover, KRPBE modulated the expression levels of neurotoxicity indicators Aβ and phosphorylated tau (p-tau) and inflammatory cytokines TNF-α, p-IκB-α, and IL-1β. Furthermore, we found that KRPBE improved the expression levels of neuronal apoptosis-related markers BAX and BCl-2 and increased the expression levels of BDNF and p-CREB. Therefore, this study suggests that KRPBE treatment has an anti-amnestic effect by modulating cholinergic system dysfunction and neuroinflammation in Aβ1-42-induced cognitive impairment in mice.

Contribution of Water-Insoluble Organic Nitrogen to Nitrogen Deposition on a Forest: a Case Study in a Red Pine Forest on the Northern Foot of Mt. Fuji, Japan

Contribution of Water-Insoluble Organic Nitrogen to Nitrogen Deposition on a Forest: a Case Study in a Red Pine Forest on the Northern Foot of Mt. Fuji, Japan

ASSESSING RED PINE SEEDLINGS USING UAV POINT CLOUDS AND FIELD-VERIFIED DATA

Abstract. Accurate, reliable, and cost-efficient approaches to forest monitoring are critical for sustainable forest management. The use of digital photogrammetry for tree height estimation is well-known among forest managers and remote sensing researchers. Satellite remote sensing has not been very successful in providing detailed and reliable estimates of tree height. Unmanned Aerial Vehicles (UAVs) are one of the latest remote sensing platforms to get forest attributes information at very high temporal and spatial resolution. This study assessed the potential of using digital aerial photogrammetry point clouds and UAV acquired high-resolution imagery to estimate red pine seedlings' height in Adirondacks, New York. Seedling's location, height, crown width, and diameter were measured from 16 fixed area sample plots, and multispectral imagery was acquired with DJI Matrice 100- UAV fitted with Micasense RedEdge-M camera. UAV was flown under clear sky conditions at 93-meter height in a single grid pattern with 80% front and side overlap. PIX4D software was used to process UAV multispectral imagery and generate Digital Surface Model (DSM) and Orthomosiac at 6.08 cm/pixel resolution along with 3D Digital Terrain Model (DTM). 3D densified point cloud layers of regeneration canopy were generated at an average density of 1.54 per m3. Seedlings were differentiated from bare ground cover through supervised image classification methods. Preliminary results of this study highlight that multispectral imagery acquired from UAVs has the potential to characterize and provide detailed structural information to estimate red pine seedlings' height.

Development of Variable-Density Yield Models with Site Index Estimation for Korean Pines and Japanese Larch

The objectives of this study were to develop site index and variable-density yield models for Korean red pine (Pinus densiflora Siebold &amp; Zucc.), Korean white pine (P. koraiensis S. &amp; Z.), and Japanese larch (Larix kaempferi (Lamb.) Carrière) in Korea. The data were collected between 2012 and 2021 from repeatedly measured empirical plots in each target stand in the North Central region of Korea: Gangwon and North Gyeongsang provinces. To develop the site index for each species, a dominant height growth model by species was developed using the Chapman–Richards function. The site index was computed with a base age of 40 years and used as an independent variable to predict the stand volume. To develop the variable-density yield models, three stand density variables, the stand age, and the site index were applied. The stand density variables used were the stand basal area, the number of trees per hectare, and the relative density. All the models were successfully developed with significant parameters and reasonable fit statistics, and the residuals analyzed presented unbiased scatter plots. Yield models with the stand basal area, or the number of trees, can be used to predict the stand volume. The yield model with relative density was flexible to apply across the stand age because the input of the absolute stand density was not required. Model simulation and comparisons with other studies also supported the applicability of the models developed in this study. The models were found to be highly applicable for predicting and simulating these targeted stands, particularly in Korea.

Intra-annual tree-ring δ18O and δ13C reveal a trade-off between isotopic source and humidity in moist environments.

Tree-ring intra-annual stable isotopes (δ13C and δ18O) are powerful tools for revealing plant ecophysiological responses to climatic extremes. We analyzed interannual and fine-scale intra-annual variability of tree-ring δ13C and δ18O in Chinese red pine (Pinus massoniana) from southeastern China to explore environmental drivers and potential trade-offs between the main physiological controls. We show that wet season relative humidity (May-October RH) drove interannual variability of δ18O and intra-annual variability of tree-ring δ18O. It also drove intra-annual variability of tree-ring δ13C, whereas interannual variability was mainly controlled by February-May temperature and September-October RH. Furthermore, intra-annual tree-ring δ18O variability was larger during wet years compared with dry years, whereas δ13C variability was lower during wet years compared with dry years. As a result of these differences in intra-annual variability amplitude, process-based models (we used the Roden model for δ18O and the Farquhar model for δ13C) captured the intra-annual δ18O pattern better in wet years compared with dry years, whereas intra-annual δ13C pattern was better simulated in dry years compared with wet years. This result suggests a potential asymmetric bias in process-based models in capturing the interplay of the different mechanistic processes (i.e., isotopic source and leaf-level enrichment) operating in dry versus wet years. We therefore propose an intra-annual conceptual model considering a dynamic trade-off between the isotopic source and leaf-level enrichment in different tree-ring parts to understand how climate and ecophysiological processes drive intra-annual tree-ring stable isotopic variability under humid climate conditions.

Physical and chemical characteristics of the bamboo culm and wood carbonized at low temperature

Physical and chemical characteristics of bamboo culm heat-treated at low temperature (200 °C to 320 °C) were analyzed to understand their carbonization mechanisms. The physical features and chemical compositions of four Indonesian and one Korean bamboo species were examined, and they were compared with red pine and cork oak after treatment. Weight loss, pH, and calorific value increased with increasing temperature. Weight loss and calorific value of the bamboo species increased from 200 to 240 °C, while those of the wood species increased from 240 to 280 °C. The pH of the bamboo and wood changed from acidic to neutral at 280 and 320 °C, respectively. The crystalline cellulose of the samples in the X-ray diffraction analysis changed to amorphous at various temperatures for each material. In Fourier transform infrared spectroscopy, all species showed a considerable change in hemicellulose peaks at 280 °C and a substantial change in cellulose peaks at 320 °C. In conclusion, the carbonized bamboo culm showed a considerable difference, at 200 °C to 320 °C, in the physical and chemical characteristics.

БЛОК-ЭФФЕКТ, ВЛИЯЮЩИЙ НА ГЕНЕТИЧЕСКИЕ ПАРАМЕТРЫ, НА ПРИМЕРЕ ИССЛЕДОВАНИЯ 23-ЛЕТНЕГО ПОТОМСТВА PINUS BRUTIA

Many environmental and biological factors could be effective on estimation of genetic parameters in progeny trials. Number of blocks (also called as replicate) is one of the most important environmental factors in these estimations. Effect of block scenarios on genetic parameters were investigated based on height and diameter at breast height in a 23-year-old progeny trial established by 4 blocks of seed stand and seed orchard seedlings of Turkish red pine (Pinus brutia Ten.) in this study. Averages were 14.14 m for tree height and 17.69 cm for diameter at breast height in polled seed sources. Generally significant (p&lt;0.05) differences among blocks, and families for the traits in the scenarios were found by results of analysis of variance. While variance of error was similar for both traits, there were large differences were estimated among other variance components for the scenarios. Individual heritability, phenotypic coefficient of variation, genetic coefficient of variation, and genetic gain varied for the traits and block scenarios. Results of the study emphasized effect of block numbers on genetic parameters