Comparison of litterfall production in three forest types in Jeju Island, South Korea

Litterfall, which is influenced by physical and biological factors, is a major pathway for carbon and nutrient cycling in forest ecosystems. The purpose of this study was to investigate monthly litterfall production in three forests in Jeju Island differentiated by forest composition and precipitation: Cheongsu(Quercus glauca as the dominant species;low precipitation), Seonheulb(Q. glauca as the dominant species;high precipitation), and Seonheulm(Q. glauca and Pinus thunbergii as the dominant species;high precipitation). Litterfall was collected monthly from April to December 2015 and divided into leaf litter, twig, bark, seeds, and unidentified materials.Seasonal patterns of litterfall production varied across stands according to their species composition. However,the amount of leaf litterfall and total litterfall were comparable among stands, ranging from 362 to 375 g m-2 for leaf litter and 524 g m-2 to 580 g m-2 for total litterfall.Oak leaf litter in May was the highest in all stands, while needle litter was the highest in December in Seonheulm.High twig litterfall in July may be attributable to high rainfall with strong winds and storms during the rainy season. Although forest type and climate factor had no influence on litterfall amounts in this study, the pattern of litterfall production was species dependent, suggesting diverse effects on carbon and nutrient cycling in these forests.

The influence of environmental factors on species composition and distribution in a community forest in Northern Thailand

Understanding the environmental factors that influence tree species composition is essential for successful management of biodiversity and sustainable use of community forest resources.This study aims to assess tree species composition and distribution in the deciduous Ban Mae Chiang Rai Lum Community Forest in Northern Thailand and to analyze the influence of environmental factors on tree biodiversity in the forest.We conducted a stratified systematic sampling of the forest’s total area of 3925 ha,and twenty-five 0.16 ha survey plots were established in three different stands of the deciduous forests to estimate and characterize the difference in biological diversity among the stands.Canonical correspondence analysis(CCA)was used to investigate the environment factors affecting such differences in biodiversity of the stands.The results showed a high diversity of trees in the forest as 197 species,144 genera,and 62 plant families were recorded.The CCA ordination identified the environmental factors—the most important of which were elevation,distance to streams,soil moisture,organic matter,and distance to communities—that signifi-cantly influenced the diversity and distribution of tree species(p<0.05)in the community forest.Our findings indicate that the implementation of drought reduction measures such as building check dams,fire protection,and monitoring community forest-product usage would be recommended to further biodiversity conservation and the sustainable use of community forest resources.

Effects of deforestation on microbial diversity in a Siberian larch(Larix sibirica) stand in Mongolia

For evaluating microbial community changes in a Siberian larch stand disturbed by forest fire or clearcutting,357 clones were randomly selected and sequenced using a culture-independent approach and 16S rRNA sequencing to characterize the bacterial composition and diversity from the different disturbed Siberian larch stands.Interestingly,the burned larch stand had an increase in the relative amounts of b-proteobacteria and Firmicutes and a decrease in Acidobacteria,while Gemmatimonadetes increased Verrucomicrobia decreased in the harvested larch stand.Microbial diversity and richness were higher in the undisturbed larch stand than the disturbed(burned or clear-cut)larch stands,and the influence of clear-cutting was more negative than that of the forest fire.This study indicates that evaluating the microbial diversity of undisturbed,burned,and clear-cutting Siberian larch stands provides information about the impact of forest disturbances on soil microbial communities,which may be helpful for understanding and evaluating soil health and devising reafforestation strategies for larch.

Aqueous extract of Protaetia brevitarsis larvae increases mTOR-mediated growth rate in zebrafish larvae

Objective:To evaluate the effects of an aqueous extract of Protaetia brevitarsis(AEPB)on the growth of zebrafish and preosteoblast MC3T3-E1 cells.Methods:The effects of AEPB on the linear growth and the expression of growth-related genes in zebrafish and MC3T3-E1 cells were assessed using various molecular techniques.Furthermore,the involvement of the mammalian target of rapamycin(mTOR)pathway in AEPB-induced growth was investigated by employing the mTOR inhibitor rapamycin.Results:AEPB administration led to a significant and dose-dependent increase in zebrafish larvae growth over time.Additionally,AEPB treatment upregulated the expression of growth hormone-1(GH-1),insulin-like growth factor-1(IGF-1),growth hormone receptor-1(GHR-1),and cholecystokinin-a(CCKA)in zebrafish.Similarly,AEPB stimulated the expression and release of IGF-1 and accelerated mTOR expression in MC3T3-E1 cells.In addition,rapamycin hindered AEPB-induced linear growth in zebrafish larvae and suppressed the expression of growth-promoting genes by inhibiting mTOR activation.Conclusions:AEPB shows growth-promoting effects by upregulating growth-related genes and activating the mTOR signaling pathway.Further investigations are warranted to elucidate its mechanisms of action and explore its potential application in the development of growth-enhancing supplements for various purposes.

High-throughput discovery of plastid genes causing albino phenotypes in ornamental chimeric plants

Chimeric plants composed of green and albino tissues have great ornamental value.To unveil the functional genes responsible for albino phenotypes in chimeric plants,we inspected the complete plastid genomes(plastomes)in green and albino leaf tissues from 23 ornamental chimeric plants belonging to 20 species,including monocots,dicots,and gymnosperms.In nine chimeric plants,plastomes were identical between green and albino tissues.Meanwhile,another 14 chimeric plants were heteroplasmic,showing a mutation between green and albino tissues.We identified 14 different point mutations in eight functional plastid genes related to plastid-encoded RNA polymerase(rpo)or photosystems which caused albinism in the chimeric plants.Among them,12 were deleterious mutations in the target genes,in which early termination appeared due to small deletion-mediated frameshift or single nucleotide substitution.Another was single nucleotide substitution in an intron of the ycf3 and the other was a missense mutation in coding region of the rpoC2 gene.We inspected chlorophyll structure,protein functional model of the rpoC2,and expression levels of the related genes in green and albino tissues of Reynoutria japonica.A single amino acid change,histidine-to-proline substitution,in the rpoC2 protein may destabilize the peripheral helix of plastid-encoded RNA polymerase,impairing the biosynthesis of the photosynthesis system in the albino tissue of R.japonica chimera plant.

Diversity patterns and phylogenetic structure of vascular plants along elevational gradients in a mountain ecosystem, South Korea

Recently, a phylogenetic diversity and community structure analysis as complementary to species-centric approaches in biodiversity studies provides new insights into the processes of community assembly. In this study, we analyzed species and phylogenetic diversity and community structures for woody and herbaceous plants along two elevational transects on Mt. Baekhwa, South Korea. The species richness and phylogenetic diversity of woody plants showed monotonic declining patterns with increasing elevation along all transects, whereas herbaceous plants showed different patterns, such as no relationship and a reversed unimodal pattern, between the study transects. The main drivers of these patterns were climate and habitat variables for woody and herbaceous plants, respectively. In addition, the phylogenetic community structure primarily showed phylogenetic clustering regulated by deterministic processes, especially environmental filtering, such as climate or habitat factors, along the two transects, although herbaceous plants along a transect depicted phylogenetic randomness as a result of a neutral process. Our findings suggest that deterministic and neutral processes may simultaneously control the community structures along small-scale elevational gradients such as local transects, although the deterministic process may be the predominant type.

Compatible taper and stem volume equations for Larix kaempferi(Japanese larch) species of South Korea

In this study, compatible taper and stem volume equations were developed for Larix kaempferi species of South Korea. The dataset was split into two groups: 80% of the data were used in model fitting and the remaining 20% were used for validation. The compatible MB76 equations were used to predict the diameter outside bark to a specific height, the height to a specific diameter and the stem volume of the species. The result of the stem volume analysis was compared with the existing stem volume model of Larix kaempferi species of South Korea which was developed by the Korea Forest Research Institute and with a simple volume model that was developed with fitting dataset in this study. The compatible model provided accurate prediction of the total stem volume when compared to the existing stem volume model and with a simple volume model. It is concluded that the compatible taper and stem volume equations are more convenient to use and therefore it is recommended to be applied in the Larix kaempferi species of South Korea.

ZIF-67@Cellulose nanofiber hybrid membrane with controlled porosity for use as Li-ion battery separator

Zeolitic imidazolate framework-67(ZIF-67) was synthesized on the surface of cellulose nanofibers(CNFs)in methonal to address the problems of unhomogeneous pore size and pore distribution of pure CNF membrane.A combination of Energy Dispersive X-Ray Spectroscopy(EDS),X-ray photoelectron spectroscopy(XPS) and X-ray powder diffraction(XRD) patterns were used to determine the successful synthesis of ZIF-67@CNFs.The size of the ZIF-67 particles and pore size of the ZIF-67@CNF membrane were50-200 nm and 150-350 nm, respectively.The prepared ZIF-67@CNF membrane exhibited excellent thermal stability,lower thermal shrinkage and high surface wettability.The discharge capacity retention of the Li-ion batteries(LIBs) made with ZIF-67@CNF,glass fiber(GF),CNF and commercial polymer membranes after 100 th cycle at 0.5 C rate were 88.41%,86.22%,83.27%,and 81.03%,respectively.LIBs with ZIF-67@CNF membrane exhibited a better rate capability than these with other membranes.No damage of porous structure or peel-off of ZIF-67 was observed in the SEM images of ZIF-67@CNF membrane after100 th cycle.The improved cycling performance,rate capability,and good electrochemical stability implied that ZIF-67@CNFs membrane can be considered as a good alternative LIB separator.

Analysis of genetic diversity and differentiation of artificial populations of yellowhorn(Xanthoceras sorbifolium) in China using ISSR markers

Yellowhorn （Xanthoceras sorbifolium Bunge） is a drought-tolerant tree in the family Sapindaceae that is native to northeastern China. Its remarkably oil-rich seeds are a reliable biodiesel source. An inter simple sequence repeat （ISSR） analysis showed genetic variation among four artificial populations in China： two in Inner Mongolia （IM）, one in Liaoning （LN）, and one in Shandong （SD）. The average percentage of polymorphic loci was 81.25 % for these four populations. The Forest Farm in SD showed the highest number of effective alleles （Ne）, Shannon index （I）, and expected heterozygosity （He）, i.e., 1.598, 0.470, and 0.325, respectively, but the lowest number of alleles （Na） as 1.600. Based on an analysis of molecular variance, 23 % of the total genetic variation was found among populations, and 77 % within populations. A principal coordinate analysis revealed two groups （Group 1： Lindonglinchang, Jianping Agriculture Research Station and Forest Farm; Group 2： Jinjilinchang）. Understanding the genetic diversity among artificial yellowhorn populations in China, detected using ISSRs, will be useful for yellowhorn conservation and improvement. Additional arti-ficial and natural populations need to be included in the future for a country-wide perspective.

An improved draft genome sequence of hybrid Populus alba×Populus glandulosa

Populus alba × P.glandulosa clone 84 K,derived from South Korea,is widely cultivated in China and used as a model in the molecular research of woody plants because of hi gh gene transformation efficiency.Here,we combined63-fold coverage Illumina short reads and 126-fold coverage PacBio long reads to assemble the genome.Due to the hi gh heterozygosity level at 2.1% estimated by k-mer analysis,we exploited TrioCanu for genome assembly.The PacBio clean subreads of P.alba × P.glandulosa were separated into two parts according to the similarities,compared with the parental genomes of P.alba and P.glandulosa.The two parts of the subreads were assembled to two sets of subgenomes comprising subgenome A(405.31 Mb,from P.alba)and subgenome G(376.05 Mb,from P.glandulosa) with the contig N50 size of 5.43 Mb and 2.15 Mb,respectively.A high-quality P.alba × P.glandulosa genome assembly was obtained.The genome size was 781.36 Mb with the contig N50 size of 3.66 Mb and the longest contig was 19.47 Mb.In addition,a total of 176.95 Mb(43.7%),152.37 Mb(40.5%)of repetitive elements were identified and a total of 38,701 and 38,449 protein-coding genes were predicted in subgenomes A and G,respectively.For functional annotation,96.98% of subgenome A and 96.96% of subgenome G genes were annotated with public databases.This de novo assembled genome will facilitate systematic and comprehensive study,such as multi-omics analysis,in the model tree P.alba X P.glandulosa.

The effect of fertilization on early growth of konara oak and Japanese zelkova seedlings planted in a harvested pitch pine plantation

We determined a suitable amount of fertilizer for konara oak（Quercus serrata） and Japanese zelkova（Zelkova serrata） planted in a harvested pitch pine（Pinus rigida） plantation. Two-year-old bare-root seedlings of konara oak and one-year-old containerized seedlings of Japanese zelkova were planted in April 2011. Three plots were established for each tree species to evaluate each of three fertilization applications. Solid compound fertilizer（N：P：K = 3：4：1） was applied yearly in three amounts（control： no fertilization, F1： 180 kg ha-1, and F2：360 kg ha-1）, every May from 2011 to 2013. We measured the root collar diameter and height, and analyzed the compartmental N and P concentrations. Compartmental N concentrations of konara oak and Japanese zelkova were not consistent based on amount of fertilization. However,the compartmental P concentrations of konara oak and Japanese zelkova were significantly different in the order of F2, F1, and control. Although the differences in growth of konara oak appeared after 3 years of fertilization,Japanese zelkova showed differences after only 2 years of fertilization owing to differences in seedling type. Growth of konara oak was affected by fertilization at F1 and F2 in2013. However, growth of Japanese zelkova was affected only at F2. Nutrient demand of Japanese zelkova appeard to be higher than that of konara oak, at least during the early growing period. Results from this study could be practically used in harvested pitch pine plantations to determine appropriate fertilization regimes.

Proximate and mineral components of Viscum album var. coloratum grown on eight different host tree species

Mistletoes are parasite plants growing on various tree species,taking nutrients from the host.Beneficial compounds of mistletoe were used in medicine and these mistletoes were commonly collected from oak species that were not well identified.We analyzed the nutritional value by measuring proximate and mineral components of Korean mistletoe(Viscum album var.coloratum)from various host trees.Carbohydrate was the most proximate component in both leaves and twigs followed crude protein,crude fiber,crude ash and crude fat.While the contents of the proximate components and minerals varied among hosts and between plant parts,leaves contained higher crude protein and ash,and more minerals except for magnesium than twigs,although no significant difference was found inmistletoe grown on Prunus mandshurica.There were significant differences of proximate and mineral contents depending on the host species.Mistletoe grown on Chaenomeles sinensis contained higher levels of carbohydrates,crude fat,crude ash,magnesium,calcium,sodium,iron,and zinc than mistletoe grown on other species.Mistletoe grown on P.mandshurica contained high mineral levels of potassium,copper and phosphorous.The nutritional value of mistletoes were greatly influenced by the host species but among the hosts,specific nutrients accumulated in leaves more than in twigs,and vice versa.Based on the analysis,Korean mistletoe contains relatively good quality of nutrients and has high potential for dietary supplements as well as for medicinal compounds.

Below-ground growth characteristics of 13-year-old Pinus densiflora on different contour conditions in a post-fire plantation in Samcheuk,Korea

We estimated the growth volume of artificially reforested Pinus densiflora in a post-fire area on three different contour conditions by comparing and analyzing the vertical and horizontal distributions of below-ground roots on each contour. The main roots at the south-facing slope (SS) developed in a long and straight form, and those on the north-facing slope (NS) in a twisted form. The side roots developed more than the main roots on the Ridge. The depth of taproots decreased in the following order: SS?>?NS?>?Ridge. The roots on the SS developed in a pile-form root structure whereas those in the Ridge and NS developed concentrically near the root collar. The amount of root development decreased in the following order: SS?>?NS?>?Ridge. The ratio of fine roots from the whole-root development decreased in the following order: Ridge?>?SS?>?NS. These results can guide considerations of growth differences according to the planting contour conditions for future establishment of P. densiflora artificial plantations.

Estimation of genetic parameters on growth characteristics of a 35-year-old Pinus koraiensis progeny trial in South Korea

The effects of genetic and environmental factors on Pinus koraiensis growth were studied based on a35 year-old progeny trial composed of open-pollinated offspring of twenty-one plus trees.Height,DBH and volume of the offspring was analyzed using restricted maximum likelihood/best linear unbiased prediction in mixed model analysis.Significant site and family effects on the three traits were observed.The distinct growth of offspring by site with disparate climates corroborated the importance of planting species in suitable conditions.Growth differences by family was significant,emphasizing the importance of identifying families with either superior or inferior performance.The parental ranking was assigned in the sites,inferring the breeding value of each plus tree.The estimates of individual heritability(h_(i)^(2))of height,DBH and volume growth were 0.169-0.645,0.108-0.331 and 0.129-0.343 respectively,with higher h_(i)^(2) of the height than DBH on each site.Coefficient of variance of genetic effect was higher with DBH in some cases,indicating the scope for selection is larger for this trait despite the lower heritability compared to height.For the variation between families in terms of the performance stability across sites,consideration of the genotype by environment interaction is required in selecting materials to be used in reforestation with Korean pine.A few families with either superior or inferior performance retained their parental ranking for at least a decade.Other families with increased growth on a particular site were identified,indicating their high breeding value and low stability.Differences in the genetic performance of the families by site requires delineation of the breeding region of the species.

Tradeoff between the number of firefighting resources and the level of fire ignition prevention efforts in the Republic of Korea

This study explores the tradeoff relationship between the number of initial attack firefighting resources and the level of fire ignition prevention efforts mitigating the probability of human-made fires in the Republic of Korea,where most fires are caused by human activities.To examine this tradeoff relationship,we develop a hybrid model that combines a robust optimization model with a stochastic simulation model.The robust optimization minimizes the expected number of fires not receiving a pre-defined response,such as the number of firefighting resources that must arrive at the fire within half an hour,subject to budget constraints and uncertainty about the daily number and location of fires.The simulation model produces a set of fire scenarios in which a combination of number,location,ignition time,and intensity of fires occur.Results show that fire ignition prevention is as cost-effective as initial attack firefighting resources given the current budget in the Republic of Korea for reducing the expected number of fires not covered by the predefined response.The mixed policy of fire suppression and fire prevention may produce some gains in efficiency relative to the dominant policy of strong fire suppression strategies.

Synergic effect of sex pheromone(7R,8S)-cis-7,8-epoxy-2-methyloctadec-17-ene on(+)-disparlure of the Asian gypsy moth,Lymantria dispar, in Korea

field attraction test of (7R,8S)-cis-7,8-epoxy-2- methyloctadec-17-ene (= 7R,8S-epo-2me-17ene-18Hy), a trace component of the sex pheromone gland of the Asian gypsy moth,(Lymantria dispar), traps that were baited with the trace component attracted more L. dispar than traps baited with (7S,8R)-cis-7,8-epoxy-2-methyloctadec-17-ene (= 7S,8R-epo-2me-17ene-18Hy) and unbaited traps. However, traps baited with 7R,8S-epo-2me-17ene-18Hy were less attractive than traps baited with (+)-disparlure [=(7R,8S)-cis-7,8-epoxy-2-methyloctadecane], the sex pheromone of L. dispar. Combination tests with (?)-disparlure, 7R,8S-epo-2me-17ene-18Hy, and 7S,8R-epo-2me- 17ene-18Hy revealed that 7R,8S-epo-2me-17ene-18Hy acted synergistically with (?)-disparlure.

Anti-inflammatory effects of natural volatile organic compounds from Pinus koraiensis and Larix kaempferi in mouse model

Natural volatile organic compounds(VOCs) extracted from conifers such as P. koraiensis and L. kaempferi have long been studied for their anti-oxidant, anti-proliferative, and anti-inflammatory effects. To evaluate the anti-inflammatory effects of VOCs from P. koraiensis and L. kaempferi, lipopolysaccharide(LPS) was administered to generate a mouse model for inflammation by the nasal route to the lungs and intraperitoneally to the whole body. VOCs of P. koraiensis and L. kaempferi were exposed to the mice by standardized wood panels with closed system. Increased levels of serum IgE and PGE2 were observed after exposure to dexamethasone and VOCs. We further determined the expression levels of inflammatory cytokine mRNA in the LPS-induced inflammation model by the reverse transcription quantitative polymerase chain reaction. Furthermore, the levels of cyclooxygenase-2, tumor necrosis factor-α, interleukin-1β, and interleukin-13 were determined in peripheral blood mononuclear cells. Those inflammatory cytokines and the key enzyme for inflammation cyclooxygenase-2 expression in PBMCs were strongly reversed by dexamethasone and VOCs. Lung tissues after nasal LPS exposure showed increased cytokine mRNA expressions which were suppressed by treatment with dexamethasone and VOCs. Furthermore, the damage induced by LPS was attenuated by dexamethasone and VOCs. In conclusion, the results from the present study indicate that VOCs of P. koraiensis and L. kaempferi have a therapeutic potential in the treatment or prevention of local and systemic inflammation due to their immunosuppressive effects.

Performance and genetic diversity of 23 provenances of northern red oak(Quercus rubra L.)after 25 years of growth in South Korea

Growth traits and genetic diversity of 23 provenances of Quercus rubra introduced from North America were analyzed in a provenance trial established with a randomized block design in Hwaseong,Gyeonggi,South Korea in 1993.Growth variables and survival at age 25 were compared with results from early stages.Height,DBH,volume and stem straightness of Q.rubra was better than those of the domestic oak(Quercus accutissima).Growth of the Dunham Island provenance from New York was the best among the 23 provenances that of the Eagle River provenance from Wisconsin was poorest.Survival rate at age25 was on average 52%.The longitude of seed origin and growth of provenance were consistently significantly negatively correlated at all ages.Growth of coastal provenances was superior to that of the inland provenances,which were separated by the Appalachian Mountains.Genetic diversity and genetic distance among the provenances were evaluated using micro satellite markers.The allelic frequencies showed high polymorphism in 10 microsatellite loci,and 292 alleles were found.Of 10 loci,two were commonly found in the 23 provenances.The mean allelic diversity and heterozygosity observed among the provenances were similar to those from the native populations of Q.rubra in North America.Nei’s genetic distance among the 23 was estimated and showed that a clear trend between geographic and genetic distances,indicating that some provenances have high genetic diversity with superior growth performance.

Biomass growth characteristics of 13-year-old Pinus densiflora S.et Z.in a post-fire plantation on different contour conditions in Samcheuk,Korea

We used preliminary data to estimate the growth volume of artificially reforested Pinus densiflora in a post-fire area on three different contour conditions. We compared the growth of P. densiflora on a south-facing slope(Ssth), north-facing slope(Snth) and ridge area(Ridge), using 7 trees selected from each stand aspect. The tree height, diameter and growth volume were measured and the dry weight of each plant part were compared and analyzed. The results revealed that the total dry weight was highest on Ssth(5992.3 g), followed by Snth(4833.2 g) and lowest on Ridge(3160.1 g). The height growth was highest on Snth(285.8 cm), followed by Ssth(274.5 cm) and lowest on Ridge(211.5 cm). The diameter growth was greatest on Ssth(7.37 cm), followed by Snth(7.10 cm) and lowest on Ridge(5.72 cm). The volume growth was highest on Ssth(4257.7 cm3), followed by Snth(3750.7 cm3) and lowest on Ridge(2093.7 cm3). Therefore, we should consider and include the concept of slope orientation together with differences in habitat environments in afforestation projects when creating artificial forests with P. densiflora. These study results can serve as important preliminary data for future establishment of artificial forest of P. densiflora in a post-fire plantation.

Aqueous extract of freeze-dried Protaetia brevitarsis larvae promotes osteogenesis by activating β-catenin signaling

Objective:To investigate the effect of an aqueous extract of Protaetia brevitarsis(AEPB)on osteogenesis using preosteoblast MC3T3-E1 cells and zebrafish larvae.Methods:Flow cytometric analysis was used to measure the cytotoxicy.Alkaline phosphatase activity was detetmined using p-nitrophenyl phosphate as a substrate.Calcium deposition was detected using alizarin red staining along with osteogenic marker expression in preosteoblast MC3T3E1 cells.In addition,vertebral formation in zebrafish larvae was detected using calcein staining and osteogenic gene expression.Results:AEPB highly promoted the expression of osteogenic markers including runt-related transcription factor 2,osterix,and alkaline phosphatase,along with elevated levels of mineralization in MC3T3-E1 cells.Moreover,AEPB accelerated vertebral formation in zebrafish larvae accompanied by upregulated expression of osteogenic genes.FH535,an inhibitor of Wnt/β-catenin,suppressed AEPB-induced osteogenic gene expression and vertebral formation,indicating that AEPB stimulates osteogenesis by activating the Wnt/β-catenin signaling pathway.Conclusions:AEPB stimulates osteoblast differentiation and bone formation by activatingβ-catenin.Therefore,AEPB is a promising material that induces osteogenesis,and is useful for the treatment of bone resorption diseases.