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This study investigated the properties and evaluated the potential utilizations of Paulownia wood (Paulownia tomentosa) grown in Korea, as wood qualities, bioenergy properties, heat-treated wood, and nanocellulose. There were significant differences in wood anatomy, physical, and mechanical properties of stem, branch, and root in Paulownia wood. The dimensional change of Paulownia wood increased after extraction in cold and hot water. Paulownia wood showed great resistance to termites and fungi. In carbonized branch wood, the heating value and pH of tension, lateral, and opposite wood increased with increasing temperature, while the char yield decreased. The cell wall structure and morphology of tension wood significantly changed after carbonization. The hemicellulose, lignin, and cellulose were decomposed with the increasing carbonization temperature. The stem, branch, root, bark, and leaf showed differences in bioenergy properties, and the heating value and ash content of all parts satisfied the standard of NIFS. Air heat-treated P. tomentosa wood showed a darker color and higher contact angle compared to the untreated wood. The lightness (L*) and wettability decreased with increasing temperature, while the weight loss, shrinkage, color change (ΔE), and relative crystallinity increased with increasing temperature. The mechanical properties of heat-treated wood decreased with increasing temperature. In FTIR analysis of wood chemical compound, the peaks at 1425cm-1 and 1370 cm-1 related lignin and hemicellulose compound did not change with the increase of heat treatment temperature, while the peak at 1031 cm-1 related to carbohydrate compound decreased with increasing temperature. Paulownia wood had low gas permeability and sound absorption, and the effect of air heat treatment in gas permeability and sound absorption was insignificant. Oil heat-treated P. tomentosa wood showed darker color than the air heat-treated wood, and the color changes increased with increasing temperature. The weight of P. tomentosa wood increased after oil heat treatment, and the weight decreased with increasing temperature. Mechanical grinding for nanocellulose was more effective for branch than stem and root. The Nano film of all samples showed similar color, and transparency. In conclusions, Paulownia tree is high potential resource for Korean wood industry such as the raw materials of lumber, bioenergy, and pulp.

This research evaluated the effect of strand pretreatment and strand mixture ratio on the properties of Dual-Species Bamboo Oriented Strand Board (DS-BOSB) from andong and tali bamboo. Andong and tali bamboo strands were steamed at 126 °C for 1 hour under 0.14 MPa pressure and followed by rinsing by 1% NaOH solution. The two types of strands were then mixed by the ratio of 100:0, 75:25, 50:50, 25:75, and 0:100 for andong and tali strand respectively. Three layered DS-BOSB was made with 0.7 g/cm3 target density and 8% phenol formaldehyde adhesive content. The shelling ratio of boards was 25:50:25 with the size of (30x30x0.9) cm3. The measurement of physical and mechanical properties for DS-BOSB evaluation referred to the JIS A 5908 (2003) standard and the results were compared with the CSA 0437.0 (Grade O-1) standard. The results showed that the steam-treated followed by 1% NaOH rinse on the strand increased the dimensional stability and mechanical strength (internal bond) of DS-BOSB. The higher ratio of tali bamboo improved the dimensional stability and internal bonding of DS-BOSB. The optimal mixture ratio to produce OSB from andong and tali bamboo were 50:50. All OSBs meet CSA 0437.0 (Grade O-1) standard.

For the manufacturing technique and utilization of traditional plywood or laminated veneer lumber with difficulties of plate deformation, warping and cracking, a novel thick veneer board prepared by 4-10 mm thick veneer as the basic unit is developing. Particularly, the super thick veneer as the core plate played an important role in manufacture thick veneer board. Thus, internal stress of release was vital for improving the properties of super thick veneer (ST veneer) obtained from poplar. In this study, we discussed the performance and preparation parameters of ST veneer including time, temperature, pressure and moisture content, which affected the elasticity behavior and improve the surface properties. Compression ratio (CR), springback ratio (SR) and bending height (BH) after springback were determined. Both compression and relicense ratio have been remarkably affected according to chance of flattening pressure and time. Moisture content and temperature have significant influence on bending height. The roughness of thick veneer decreased with increasing temperature and time whether cross or parallel to grain. The contact angles decreased with increasing pressing temperature resulting in better wettability. XPS results showed that temperature played a significant role in chemical changes of veneer surface. It was demonstrated that thermal-press treatment could improve the properties of ST veneer, and appropriate parameters could develop its functional utilization in the field of composite materials.

The objective of this research was to analyze the effect of hot-pressing temperature and Urea Formaldehyde (UF) and Methylene diphenyl diisocyanate (MDI) ratio on the physical and mechanical properties of particleboard. The first experiment was focused on pressing temperature treatment included 130, 140, 150, and 160oC. Particle is bonded using a combination of UF and MDI resin at a ratio of 70/30 (%w/w). Furthermore, the second experiment was focused on UF/MDI ratio treatment included of 100/0, 85/15, 70/30, 55/45 (% w/w). The particle was pressed at 140oC temperature. All of the particleboard in this research was produced in size of 25x25 cm2 using 12% resin content which target thickness and density were 1 cm and 0.75 g/cm3 respectively. Pressing time was determined to 10 minutes. Before the tests, the board was conditioned for 7 days. Good dimensional stability and mechanical properties were resulted by boards treated in 140oC temperature. The best ratio of UF/MDI was 55/45. The increase in the MDI adhesive ratio had an effect on the increase in MOE and MOR, however, the internal bond was in the contrary.

Cork granules are by-products after the production of various cork products, such as wine stoppers, and are considered as a valuable resource because of their good elasticity and slip resistance. In this study, the applicability of cork granules as paving materials for walkways and children's playgrounds was investigated. Cork granules with various particle sizes from 1 mm to 8 mm were obtained from Portuguese cork oak (Quercus suber). As a result of manufacturing cork paving materials with a thickness of 15 mm, their tensile strength was found to be 0.5 MPa or more. However, the tensile properties of the paving material made only with cork granules with a particle size smaller than 2 mm were less than 0.2 MPa. Furthermore, other physical properties of cork paving materials such as shock absorption, sliding resistance, and vertical deformation were all suitable for human activity. As a result of surface temperature measurement by a thermal imaging camera in summer, it was found that the cork paving material was more effective in alleviating the heat island phenomenon compare to the rubber one.

This study observed and compared the anatomical characteristics of compression, lateral, and opposite woods in the stem wood of Pinus merkusii and Agathis loranthifolia. The anatomical characteristics were observed with optical microscopy, scanning electron microscopy, and x-ray diffractometry. Compression wood of both species showed a gradual transition from earlywood to latewood, circular tracheid shape, many intercellular spaces, helical cavities, slit-like bordered pits, and piceoid pit in the cross-field. Helical ribs occurred only in the compression wood of Pinus merkusii. Lateral and opposite woods of Pinus merkusii showed mostly uniseriate bordered pits, pinoid and window-like pit in the cross-field, while those of Agathis loranthifolia mainly showed multiseriate bordered pits and taxodioid and cupressoid pit in the cross-field. In both species, compression wood had the shortest tracheid length, the smallest tracheid diameter, the thickest cell wall, the highest ray number, the smallest pit number per cross-field, the smallest pit diameter, the smallest relative crystallinity, the smallest crystal width, and the largest microfibril angle (MFA) among the parts. Compression wood had the smallest uniseriate and fusiform ray height in Pinus merkusii, while compression wood of Agathis loranthifolia showed the highest uniseriate ray height. Lateral and opposite woods showed a similar ray number, ray height, tracheid length, MFA, and crystalline characteristics in both species. In Pinus merkusii, lateral wood had larger tracheid diameter and thicker cell wall than opposite wood, while lateral and opposite woods had similar pit numbers per cross-field and pit diameter. In Agathis loranthifolia, lateral and opposite wood showed a similar tracheid diameter and cell wall thickness, while lateral wood showed greater pit numbers per cross-field and pit diameter than opposite wood. In conclusion, compression wood showed distinctive anatomical characteristics with lateral and opposite woods in both species, while lateral and opposite wood showed a difference in tracheid diameter, cell wall thickness, and pit number and diameter in the cross-field.

The objective of the study was to determine and compare the effects of the different heat treatment media on the physical and mechanical properties of Paulownia tomentosa and Pinus koraiensis woods. Heat treatment was conducted in oil and air at 180, 200, and 220°C for 1, 2, and 3 hours. The properties of the heat-treated woods including color, weight, density, volume shrinkage, compression strength, and hardness, were investigated. Oil heat-treated wood exhibited a darker color than the air heat-treated wood. Weight and density of oil heat-treated wood showed a remarkable increase, but those of air heat-treated wood slightly decreased. Oil heat-treated wood exhibited lower volume shrinkage compared to air heat-treated wood. Axial compressive strength increased by oil heat treatment at all temperatures, while in air heat treatment the axial compressive strength increased at 180 and 200°C and decreased at 220°C. The hardness of oil heat-treated Pinus koraiensis wood increased, in contrast with Paulownia tomentosa wood. In air heat treatment, both wood species showed a decrease in hardness. In conclusion, there were some differences in the effect of the heat treatment media on the physical and mechanical properties between the two wood species and heat treatment in oil is more effective method to improve some wood properties than heat treatment in air.

The objective of this study was to determine the effect of delignification on the properties of bamboo cellulose nanofibers and its nanocomposites. Milled bamboo powder (150-200 mesh) was delignified with sodium chlorite-acetic acid (SC-AA) treatment in reactions 1, 2, 3, and 4 cycles. The delignified bamboo fibers were then fibrillated using wet disk mill (Supermasscolloider MKCA6-2, Masuko Sangyo, Japan). The morphology, functional groups, and crystalline properties of the fibrillation products were characterized. Bamboo cellulose nanofibers and polyvinyl alcohol (PVA) matrix were used to prepare nanocomposites. The physical, optical, and mechanical properties of the nanocomposite were evaluated. The results showed that lignin content of ampel bamboo decreased 12% to 83% after SC-AA delignification. The diameter of ampel bamboo cellulose nanofibers decreased with increasing delignification. The Fourier Transform Infra-Red (FTIR) spectra confirmed that there was a decrease in lignin content although there were still residues left on the cellulose nanofibers. The crystallinity and atomic size of the crystals decreased with increasing delignification reaction. The water absorption and solubility of nanocomposites decreased with increasing delignification reaction on ampel bamboo. Ampel bamboo cellulose nanofibers with 4 times delignification had the highest nanocomposite transparency. Nanocomposite strength increased with increasing delignification.

Although chemical modifications (grafting ‘onto’) of CNCs have been successfully adopted to enhance theirdispersibility in apolar matrices and solvents, the problem of the dispersion level of mCNCs (chemically modified CNCs) in apolar matrices above a certain loading of nanoparticles remains an issue. CNCs were successfully modified using toluene diisocyanate, and the effects of the molar mass (Mw) and crystallinity (Xc) of semicrystalline poly(lactic acid) (PLA) on the mechanical and thermal properties of mCNC filled PLA nanocomposites were investigated. An increase in the mechanical properties of the PLA nanocomposites with mCNCs implied that Mw and Xc of PLA can be key factors to improve the dispersion level of mCNCs. In our solvent dilute polymer system, despite a reduction in the crystallinity of PLA with increasing mCNC loading level, the melting temperature of the PLAs remained constant due to the mCNC effect, which hinders the chain mobility of the PLAs. The results demonstrated that a fundamental understanding of the crystallinity and molar mass of polymers as well as surface modification of CNCs can be a reasonable approach to take full advantage of the potential usage of CNCs as reinforcements.

Mechanochromism is a stress-induced color change of materials and motivates smart applications such as stress-sensing, material damage-reporting, and information security. The principles to give mechanochromism include mechanophore, aggregation-induced emission, and structural colors. Cholesteric liquid crystal (ChLC) exhibits a structural color based on its selective reflection of circularly polarized light (CPL). Several cellulose derivatives are capable of expressing ChLC and can be a key component to produce mechanochromic materials. We have recently found that polymerized composites of ChLC solution of ethyl cellulose in acrylic acid demonstrated not only wide-ranging color change but also circular dichroic inversion upon mechanical stimulus at >120°C. Their original color and circular dichroism were recovered by post-thermal treatment. For propionylated hydroxypropyl cellulose, ChLC structure could be immobilized with various monomers, to which the contribution of hydrogen bonding and moderate compatibility was confirmed spectroscopically [Polymer 2019]. The extension of applicable monomers led to wide-ranging control of temperature and stress for mechanochromism expression. Most recently, we have succeeded in elucidating the effect of birefringence to the inversion of CPL handedness and simulating the mechanochromism. Cellulose-based ChLC is thus a promising material for smart mechanochromic material design.

Over a decade, cellulose based nanomaterials were hot research topics even cellulose is most useful biomass component for many applications. Last a few years, we have started to explore lignin based nano particles. However, the utilization of hemicellulose (typically 5-carbon sugars) is still the bottleneck of the current biorefinery industry. In this presentation after introducing our research in cellulose nanofibers, I will give an overview of our recent efforts: 1). Introducing hot-water extraction at relatively low temperature (120–180ºC) as an efficient pre-treatment strategy for the extraction of hemicellulose sugars from biomass as part of biorefinery process; 2) To utilize hemicellulose sugar stream, an effective hot-water pre-extraction and carbonization strategy of lignocellulosic biomass was introduced to synthesized fluorescent carbon dots (CDs) with tunable photoluminescence (PL) intensity and quantum yields (QYs) without carbonization of the entire biomass. No additional doping agent was used according to an innovative bio-refinery concept. The yields of de-branched sugars in hot-water extractions can be adjusted with increasing temperature between 120–180 ºC, thereby leading to distinct N-doping CDs after high temperature carbonization (220 ºC for 5 h); 3) Processing cellulose and lignin solid into lignin contained cellulose nanofibers and demonstrating a few unique applications such as superhydrophobic coating, nanodiamonds.

Dipalmitoylphosphatidylcholine (DPPC) liposome was surface-decorated with hydrophobically modified thiolated carboxymethylcellulose (Hm TL-CMC)-capped gold nanoparticle (GNP) and hydrophobically modified poly(N-isopropylacrylamide) (Hm PNIPAM). GNP was prepared using Hm TL-CMC as a reducing agent for gold ions and a capping material for GNP. DPPC liposomes incorporating Hm TL-CMC-capped GNP and Hm PNIPAM were prepared by a film hydration and sonication method and they exhibited a multi lamellar structure along with GNP on its TEM micrograph. The temperature-responsive release of DPPC liposome was promoted when the liposome was incorporating Hm PNIPAM, possibly due to the thermal contraction of the polymer chains. DPPC liposome incorporating Hm TL-CMC-capped GNP showed a NIR-responsive release, possibly due to the photo thermal effect of GNP, and the NIR-responsive release was enhanced when the liposome was bearing Hm PNIPAM.

In this study, novel nanozymes, CNF/FeNCDs and CNF/PdNPs were prepared by synthesis of carbon dot and Pb nanoparticles on cellulose nanofibril (CNF), and their applications with its peroxidase activity and dye degradation were evaluated. For preparation of CNF/FeNCDs, Periodate oxidation of cellulose nanofibrils (CNF) is performed to produce dialdehyde functions. In a typical reaction, 100 g of 0.5% CNF is reacted with 500 mg sodium periodate at 45 °C temperature for 4 hours under dark conditions. As produced DACNF have an aldehyde content of 1.25 mM/g and yield was above 90%. Fe, N-doped carbon dots (FeNCDs) were prepared by a hydrothermal reaction of citric acid, FeCl2.4H2O and ethylene diamine, and then bound to dialdehyde cellulose nanofibrils via Schiff base reaction. Pd nanoparticles (PdNPs) on CNF were prepared by a rapid microwave. Subsequent reduction of Pd2+ ions was achieved using ethylene glycol (EG) as reducing agent under microwave irradiation. Effect of EG amount and microwave irradiation time was also studied. Comparative experiments under conventional heating revealed that 2 h of time is required for complete reduction whereas the microwave irradiation offered in just 120 s. It was observed that the FeNCD and PdNPs having a diameter of 5-10 nm were synthesis on CNFs. Binding of FeNCDs and PdNPs on CNF was confiremd by X-ray photoelectron spectroscopic analysis. X-ray diffraction patterns unveiled the face centered cubic (FCC) crystal structure of PdNPs. Peroxidase activity of CNF/FeNCDs and CNF/PdNPs was studied by catalyzing the H2O2 mediated oxidation of 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). The excellent peroxidase activity of both nanozymes was demonstrated through UV-vis spectra analysis of Ox-ABTS. By detecting the hydrogen peroxide formed by the cholesterol oxidase with the nanozymes, the cholesterol detection ability of the nanozymes was verified.

Silver nanoparticles (AgNPs) exhibit broad spectrum antibacterial effect, but their cores after use can persist in the environment, which presents a toxic effect on humans. To address this issue, silver-based biomaterials are regarded as green alternatives to AgNPs. In this study, we used kraft lignin, a green and biodegradable polymer derived from wood biomass, to prepare an aminated lignin-silver complex (Ag@AL complex) as an alternative antibacterial agent. A facile approach for preparing aminated lignin (AL) was realized by the amination of kraft lignin using 2-chloroethylamine hydrochloride in water solvent. The nitrogen content of optimized AL was 4.37%. Ag(Ⅰ) could be captured and reduced to metallic Ag(0) by AL, thereby forming AgNPs on the surface of AL. Importantly, the obtained Ag@AL complex was proven to be an effective antibacterial agent against gram-positive (Bacillus cereus, Staphylococcus aureus) and gram-negative (Salmonella enterica) bacteria.

3D-printed biodegradable cellulose nanocrystal (CNC)-reinforced chitosan/silk fibroin scaffolds were synthesized as an advanced material for regenerative medicine application. The developed bio-inks were characterized using Fourier transform infrared spectroscopy and X-ray diffraction analysis. The composite scaffolds exhibited better swelling potential and better degradation potential than the pure polymer scaffolds. The cytotoxicity of the developed scaffolds was measured using the WST-1 assay in the presence of human bone marrow-derived mesenchymal stem cells (hMSCs). Improved cell viability and mineral deposition were observed with composite scaffolds vis-à-vis pure polymer scaffolds, showing their improved biocompatibility and mineralization potential. Upregulation of osteogenic associated gene markers was observed in the composite scaffold-treated media compared to the control, indicating enhanced osteogenic efficiency. The osteogenic induction process occurs via the mitogen-activated protein kinase pathway. Higher M1 macrophages polarization occurred in the scaffolds treated media after 24 h of incubation, which assisted the angiogenesis in bone tissue regeneration during the initial stage. Moreover, shifting from M1 to M2 macrophages polarization was observed in the scaffolds treated media after 3 days of incubation, suggesting its tissue regeneration potential. Compared to the control group, enhanced bone regeneration was observed in the calvaria defect rat model with the printed scaffolds, indicating their superior osteogenic efficiency. These results demonstrate that the printed scaffolds are promising materials for vascularized bone-healing applications and provide practical approaches for biomaterial development.

Multi-layered cellulose nanocrystal (CNC) structure with hyaluronic acid (HA) and doxorubicin hydrochloride (DOX) was fabricated for tumor-targeted drug delivery. DOX was coated to the outer surface of rod-shaped CNC via an electrostatic interaction. Then, DOX@CNC composites were wrapped with HA for CD44 receptor-mediated endocytosis in cancer cells. Anionic charged HA was bound to DOX@CNC for CD44 receptor-positive tumor-targeted drug delivery. HA@DOX@CNC with 327 nm length, 12 nm width, -38 mV zeta potential, and 3% drug content was successfully prepared. Designed HA@DOX@CNC composite exhibited higher uptake and antiproliferation efficiencies in lung adenocarcinoma (A549 cells). Cy5.5 (which is one of near-infrared fluorescence dyes)-conjugated HA-covered DOX@CNC was injected intravenously to A549 tumor-implanted mouse model and the biodistribution profile was monitored by optical imaging. HA@DOX@CNC group displayed higher tumor accumulation efficiency following intravenous injection. Also, it did not induce any serious systemic toxicities. It can be concluded that HA@DOX@CNC can be used efficiently and safely for systemic cancer therapy.

Cellulose nanocrystals (CNCs) extractable from plants have excellent biodegradability and biocompatibility. Also, the CNC films can be easily fabricated via solution process. In this respect, the CNCs are emerging materials for various applications. For a use of CNCs in electronic devices, mixing CNCs with other functional nanomaterials can be an efficient strategy to increase conductivity. In this study, we fabricated and characterized CNC-graphene hybrid films on a polyethylene terephthalate substrate using a bar-coating method. The changes in the sheet resistance of the flexible CNC films were observed by varying the graphene dispersion ratio. The structural property and electronic structure of CNC-graphene films were investigated using scanning electron microscopy and X-ray photoelectron spectroscopy. Based on these results, we discuss the physical origin of changes in the sheet resistance. In addition, we fabricated the CNC-graphene paper by adding a glycerol additive. The properties of the CNC-graphene paper were significantly varied by the choice of a graphene dispersion type. The use of graphene dispersion including functional groups results in higher uniformity. Thus, the same sheet resistance values of CNC-graphene paper could be obtained on both front and back sides.

The zonal climax in humid temperate areas in East Asia is the Primary Mixed Forest of Korean Pine and Broadleaved Tree Species and most of them has been derived into secondary forest currently. Many of the secondary forest has become the mixed forest by artificially planted Korean pine and naturally regenerated broadleaved leaved tree species through the dynamic management approach of “planting conifers and reserving broadleaved tree species” in Northeast China’s temperate forest region. For promoting the growth of Korean pine trees and broadleaved trees harmoniously, microspace of individual trees of Korean pine was quantitatively regulated according to Opening Degrees (OP=1.0, 1.5 and 2.0) and the morphological development of Korean pine trees was elucidated by long time positioning investigation from 12 sample plots in 3000 m2 in University Forest of Northeast Forestry University at Maoershan, which is located in Maoershan Town, Shangzhi City, Heilongjiang Province, China. The results were shown as follows: (1) the ratio of lower 2 wheel lateral branch base diameter to diameter at breast height (BBD/DBH) could be the indicator of under canopy Korean pine tree light environment, the smaller the better; (2) the response patterns of height, diameter, crown width and individual tree volume of different age-class Korean pine trees to each OP were different, OP=2.0 was significantly better than other two OPs for 30-year-old and 15-year-old Korean pine populations but no certain pattern for that of 9-year-old Korean pine population, especially, the individual volume of Korean pine trees in OP=2.0 were 197% and 113% higher than that of OP=1.0 and 1.5 respectively for 30-year-old population and 212% and 343% for 15-year-old population but no evident changes for 9-year-old population; ten year data of height, diameter and individual volume showed the same patterns; (3) 28.2% Korean trees in OP=2.0 for 30-year-old population has reached to the upper tree canopy height but only 4.1% and 1.1% for other two OPs. Conclusion: Opening degree 2.0 treatment for Korean pine tree was the proper one that could promote fast growth of under-canopy planted Korean pine trees.

There are only few studies of Russian Far East climate; moreover, dendrochronological studies in the continental part of this huge territory are absent. Meanwhile, most of tree species form northeastern China, Korean peninsula and Japan are presented in this region. In addition, the Russian Far East is the northern boundary of some tree species ranges and this significantly increases their climatic sensitivity. Also, some forests in the Russian Far Eastern have not been subjected to human activity for the last 2000-4000 years. Finally, the southern part of the Russian Far East is sensitive to global climatic changes as it is under the influence of cold air flow from northeastern Asia during the winter and summer monsoons. All the factors create favorable conditions for dendroclimatic studies. Mixed forests with Korean pine (Pinus koraiensis Siebold et Zucc.) are the main vegetation type Russian Far East. This area is the northeastern limit of the Korean pine-broadleaved forests range, which are also found in northeastern China, on the Korean peninsula, and in Japan. The Sikhote-Alin mountains is one of the few places where significant areas of old-growth Korean pine-broadleaved forest remain. The territory of Russian Far East is characterized by a monsoon climate which is determined by the interaction of the Pacific Ocean and the Siberian anticyclone. So, the radial growth of Korean pine in the study region is mainly limited by the pre-growth autumn-winter season temperatures and spring-to-early summer precipitation. Using the tree-ring width of Pinus koraiensis, we reconstructed the mean minimum temperature of the previous August-December for the southern part of Sikhote-Alin Mountain Range, northeastern Asia, Russia, for the past 486 years. Also, we reconstructed April–June precipitation for the southern, central, and northern Sikhote-Alin Mountain Range for the past 300 years. So, we obtained the first climate reconstructions for this region, and for the first time for northeast Asia, we present a reconstruction with a length exceeding 486 years. The results of our research are important for studying the climatic processes that have occurred in this region and northeastern Asia and for situating them within the scope of global climatic change.

The signs of global warming are everywhere, and are more complex than just climbing temperatures. Climate change encompasses not only rising average temperatures but also extreme weather events. More frequent extreme weather events and water scarcity across the U.S. make it more expensive and difficult to sustain crop production. Therefore, effective breeding of climate resilient crop cultivars combined with adaptation of crop production systems to better cope with the challenges of future climate change are of key importance. High-throughput genotyping and phenotyping technologies offer a new approach to examine Genetics (rice and the associated soil microbiome) x Environment x Management interactions for developing climate resilient crop cultivars with enhanced production and quality as a means to mitigate the effects of a changing climate.

This study was conducted to test the statistical significance of fertility variation among families and to select superior families for acorn production in the breeding seedling seed orchards (BSSOs) of Quercus acuta and Quercus glauca. The seed orchards were located in Jeju island and established by seedlings raised from selected parents for genetic testing in 2006. Re-selection from the BSSOs would be necessary to establish advanced generation seed orchards in order to expand the afforestation of evergreen warm broad-leaved trees in response to climate change. In the spring of 2021, the numbers of female and male flower were counted from ten individuals per family in the BSSOs. The female flowers were counted individually over the entire crown, but the number of male flowers was estimated by multiplying the average number of flowers per branch by the total number of branched bearing flowers. To test statistical significance of which parameter is not satisfied through the normality test, we used a nonparametric analysis. Correlation analysis was performed to quantify the association between female and male flower production. As the results, the significant difference of flower production among families was found in both seed orchards. The averages of female flower production were 65.3 and 181.9 in Q. acuta and Q. glauca. The positive rank correlation was existed between male and female flower production in the BSSOs. Broad-sense heritability on female and male flower production were 0.191 and 0.147 in Q. acuta, and 0.285 and 0.068 in Q. glauca, respectively. Sexual asymmetry (e.g., maleness index) between female and male, and contribution variation among families (e.g., parental balance) were analyzed to find reasonable alternatives in the management of seed orchards. Effective population size of seed crops was predicted as a concept of status number. Loss of gene diversity (accumulation of group coancestry) would not be alarming in the BSSOs. Our results would be helpful to select breeding materials for establishing new seed orchards and supplying genetically improved seeds of evergreen warm tree species, which is one of the backbones of strategy of carbon sink in the 2050 Carbon Neutrality of Korea Forest Service.

Castanea crenata and Diospyros kaki have been cultivated for a long time and main forest crops in Korea. These are distributed nationwide, and commercial cultivations are in the southern part of Korea, except the mountainous sites (highland region). However, due to climate change, the optimal regions of the crop trees are shifting northward. We planted various cultivars of two species in mountainous site to investigate their adoptability for future cultivation. We adopted image and hyperspectral spectrum to monitor their phenological and physiological responses to the environment in the current optimal cultivation (southern region) and experimental site (northern mountainous). The chlorophyll content of both species was higher in the cultivation site than in the mountainous site. On the other hand, the chlorophyll fluorescence of C. crenata in July was higher in the mountainous site than cultivation site. The stomatal conductance showed a large difference by each month and sites due to local weather condition. D. kaki in the mountainous site showed that the leaf area did not increase for each tree even when the stem grew. Also, the increase in vitality of D. kaki in the mountainous site was decreased compared to the cultivation site. It was investigated that D. kaki was more difficult to adapt than C. crenata. On the other hand, ‘Okgwang’ showed the best cultivars of C. crenata in the mountainous sites.

The introduction of genotype II African swine fever (ASF) virus (ASFV) into the Korean peninsula in 2019. The outbreak of ASF in domestic pigs occurred on September 16, 2019, right after the autumn rainy season ended. Since then, 14 more cases have occurred, and there have been no additional cases until the last occurrence of Inje area, Gangwon-do. It resulted in unprecedented disease propagation via slow geographical expansion through wild boar populations, short- and long-distance human-mediated translocations, and incursions into naïve wild boar and domestic pig populations. The disease is now progressing slowly, mainly in the mountainous regions of Gangwon-do. The global dimension of the current epidemic shows that all countries need to be prepared for an introduction. In its natural habitat in Africa, ASFV is maintained within an ancient cycle between soft argasid ticks and the common warthog. Once introduced to the domestic pig population, direct and indirect virus transmission occurs with or without involvement of the tick vector in the pig-tick and domestic pig epidemiological cycles respectively. In the domestic pig cycle, human activities involving pigs or farming activities in areas where ASF positive wild boars have been found. ASF epidemiology in the presence of wild boar and northern European climates where it already occurred and still suffers from the disease has proved to have specific characteristics, described in the wild boar-habitat epidemiological cycle. In this cycle wild boar carcasses and the resulting contamination of the environment play key roles in virus persistence. However, in addition that this virus is highly resistant to the environment, the fact that topographical features of lots of mountainous areas Korea has, makes it more difficult to control. In both the wild boar-habitat and the domestic pig epidemiological cycle, fully implemented biosecurity is the key for stopping virus transmission and controlling the disease. Positive examples from the Czech Republic and Belgium show that control and eradication of ASF from the wild boar-habitat cycle can be achieved. Both these cases, as well as the example of Sardinia, where ASFV genotype I now seem very close to eradication after more than 40 years presence, further underline the importance of involving, engaging and understanding all stakeholders in the value chains from farm and forest to fork in order to accomplish ASF control and eradication.

The zoonotic diseases, virus and bacteria-borne, are major concern to the global security. African swine fever (ASF) is high contagious and high mortality haemorrhagic viral disease in domestic and wild boar (Sus scrofa). Bacteria-borne zoonotic diseases such as Salmonella and Shiga toxin-producing Escherichia coli were detected in wild boar (S. scrofa) in Korea. However, ASF is found in almost all countries around the world, particularly in sub-Saharan Africa. The outbreaks have spread through China, Mongolia and Vietnam, South Korea, North Korea, India as well as northeast region Myanmar, Bhutan, and Bangladesh during the last two years. But on 17 September 2019, the first outbreak of African swine fever in a pig farm was confirmed in South Korea. Based on genetic sequence with the phylogenetic analysis ASFV isolates were in South Korea belong to genotype II and serogroup 8. However, genomic characterization whole genomic sequence of ASFV isolates are required for typing, control measures, management, and development of vaccine against ASFV. Till date, there is no effective approved vaccine or antiviral drugs in the market against ASF infection. Therefore, control/prevention and management is the best strategy to handle of the ASF infection. ASF is a transboundary animal disease (TAD) that can be spread by live or dead pigs, domestic or wild, and pork products. The prevention strategies of ASF are early detection, design more cost-effective surveillance e.g. modelling for transmission dynamics, find out the risk factors including role of wild boar and soft ticks, and biosafety and biosecurity measures. In our presentation, we discuss about the viral and bacterial zoonotic diseases in future concerns, cost-effective surveillance, and mitigation measures of zoonotic (ASF) diseases.

In order to cope with African swine fever, wild boar population density surveys were conducted in four regions of Gangwon-do (Hoengseong, Hongcheong, Yanggu, and Hwacheon), and a study on home range was conducted in Yanggu. Camera trap was used for the wild boar population density survey, and a total of 16 cameras were installed in 4 regions, with 4 cameras in each region. As the results of analyzing the camera trap data collected for six months from November 2020 to May 2021, the average monthly wild boar population densities were 0.1(±0.09)/㎢ in Yanggu, 0.07(±0.09)/㎢ in Hwacheon, 0.06(±0.09)/㎢ in Hongcheon, and 0.04(±0.06)/㎢ in Hoengseong. Home range was calculated based on the movement of 50 days by attaching a GPS transmitter to a wild boar captured in Yanggu (a female of one year age). The area of home range was MCP 100% 12.01㎢, MCP95% 5.42㎢, and MCP50% 1.21㎢.

In October 2019, Korea confronted with the first African Swine Fever(ASF) cases in wild boar. Although Korea placed enormous efforts, including installing fences, hunting wild boars, and removing infected carcasses immediately to slow down the spread of ASF, ASF in wild boar rapidly expanded throughout northern Korea. As of April 2021, a total of 1,312 cases occurred in 13 cities/counties. World organization for animal health noted that the spread of ASF is closely related to the wild boar density, and management of the wild population is inevitable for ASF prevention because no vaccine nor cure is currently available. Therefore, understanding the population density in and around the ASF outbreak areas is essential for systematic population control. Different methods such as drive counts, snow tracking, pallet counts, and distance sampling have been used to estimate the abundance or density of wild boars. We compared these methods with respect to different conditions. Among various methods, using camera traps with statistical analyses can estimate the density with high accuracy and precision. Camera trapping also allows collecting additional ecological data such as activity patterns related to hunting and occupancy. However, considering the mountainous landscape in Korea, the installation effort could be overwhelming. A reliable density estimate will help set hunting numbers to manage the wild boar population and contribute to eradicating ASF in Korea.

African Swine Fever Virus (ASFV) is a severe viral disease spreading rapidly worldwide, including Korea, in both wild boar (Sus scrofa) and domestic pig (Sus domesticus populations. An individual based model (IBM) was developed to simulate movement of individual wild boars concurrently liking with ASFV transmission. Movement of wild boar followed the rules according to the hidden Markov model (HMM) to select optimal habitats with different natural resources (leaf types and water). HMM parameters were obtained based on field data observed in Bukhan Mountain, Seoul, Korea, from June, 2018 to May, 2019. Subsequently ASFV transmission was incorporated into the model when healthy boars contacted infected boars. The model output was presented in the Hoengseong area, Korea. Simulation results indicated that contact rate and carcass removal frequency were important in controlling disease transmission during the course of wild boar movements.

Potential serious impacts of the climate change on our living environments have evoked global interest in creating low carbon cities. The field of landscape architecture is directly associated with design and construction of low carbon cities. This presentation explores the existing trends and future new directions in landscape architecture to establish a low carbon eco-city in Korea. Much research in the field has been conducted for the last 25 years from the middle of the 1990s, even though scientists concerned have not been diverse. Trends of the research can be classified into two grand types. They are a) net carbon uptake by urban greenspace and b) carbon emissions from production or construction of landscape materials and facilities. The former type includes three sub-types: a) carbon uptake and storage by urban greenspace, b) carbon reduction from building energy savings by tree planting, and c) carbon release from greenspace maintenance. These achievements could be useful in understanding carbon cycling of urban ecosystem. However, there is still limitation in quantifying carbon budget for urban structural components. Future research directions in landscape architecture require estimating especially the size of greenspace supply to offset carbon emissions and net carbon reduction by land cover types and landscape facilities through life cycle analysis. These tasks could contribute to land use planning on an urban scale and spatial design on a site scale to help create a low carbon eco-city.

Low-carbon landscape is a landscape element composed of landscape materials and facilities that can minimize carbon footprint or maximize carbon absorption. Minimizing the carbon footprint in the landscape creation process is possible through eco-friendly material selection and low management technology. Carbon absorption is achieved by trees and soil to store and sequester carbon generated within the city. As such, the low-carbon landscape has emerged as one of the core elements of a carbon-neutral city since the 2000s. However, research on low-carbon landscape in Korea is still in the conceptual establishment stage. If the design elements of the low-carbon landscape are derived through a systematic and systematic approach, it will be a useful metric in Korea's ecological landscape field, urban planning, and spatial management in the future. In this study, the low-carbon landscape constituent resources were explored based on the landscape design criteria in the urban landscape space, which is a low-carbon landscape. The landscaping elements constituting the low-carbon landscape were classified into four categories: space, facilities, materials, and planting, and each detailed element was derived. The carbon-neutral effect of the Korean landscape space was discussed using the derived components of the low-carbon landscape.