Evergreen Broad-leaved Trees Research Articles

경기만 해안 및 도서지역 상록활엽수 식재 타당성 연구

경기만 해안 및 도서지역 상록활엽수 식재 타당성 연구

Complete plastome sequence of Syzygium forrestii Merr. et Perry (Myrtaceae): an endemic species in China

Syzygium forrestii Merr. et Perry is an evergreen broad-leaved tree, 8–15 metres tall. It is mainly distributed in the Southwest of China (Nu river valley to Xishuangbanna area), growing from 800 to 2400 metres above sea level. It grows in the evergreen broad-leaved forest and the hillside shrubbery. It is an endemic plant species in China. At present, it has not been artificially introduced and cultivated. However, its complete plastome information and systematic position is still unknown. Here we report and characterize the complete plastid genome sequence of S. forrestii in an effort to provide genomic resources useful for promoting its conservation and systematic research. The complete plastome is 159,996 bp in length and contains the typical structure and gene content of angiosperm plastome, including two inverted repeat (IR) regions of 26,414 bp, a large single-copy (LSC) region of 88,560 bp and a small single-copy (SSC) region of 18,608 bp. The plastome contains 115 genes, consisting of 81 unique protein-coding genes, 30 unique tRNA gene and 4 unique rRNA genes (5S rRNA, 4.5S rRNA, 23S rRNA and 16S rRNA). The overall A/T content in the plastome of S. forrestii is 63.10%. The complete plastome sequence of S. forrestii will provide a useful resource for the conservation genetics of this species as well as for the phylogenetic studies of Myrtaceae.

Habitat and Conservation Status of Rufous-necked Hornbill in Jigme Singye Wangchuck National Park, Bhutan

The Rufous-necked Hornbill habitat characteristics and conservation was studied in Jigme Singye Wangchuck National Park (JSWNP). The focal-bird approaches was used to determine the habitat components such as, the structure on vegetation, species composition; food-trees and nesting were assessed in the hornbill habitat. A total of 78 respondents were interviewed from five villages using semi-structured questionnaires. Vegetation assessment showed that the evergreen broad-leaved tree has the highest percentage share of 62.5%. A total of 42 tree species and 9 food-tree species, dominated by Lauraceae family in Tingtibi, and 35 tree species and 8 food-tree species, dominated by Hemamelidaceae in Nabji were recorded. Diameter at breast height size of tree species ranges from 14 cm to 250 cm. Nests were found in the cavities of living tree trunks of different tree species having large girth and tall trees. Rural timber extraction, land use changes, cattle grazing, and the roads and utility corridors contribute significant threats to the hornbill habitat. About 93.6% of the respondents had strong liking towards hornbill. Using hornbill as flagship or umbrella species would contribute to long-term conservation of hornbill.

Spatial variability of organic matter properties determines methane fluxes in a tropical forested peatland.

Tropical peatland ecosystems are a significant component of the global carbon cycle and feature a range of distinct vegetation types, but the extent of links between contrasting plant species, peat biogeochemistry and greenhouse gas fluxes remains unclear. Here we assessed how vegetation affects small scale variation of tropical peatland carbon dynamics by quantifying in situ greenhouse gas emissions over 1 month using the closed chamber technique, and peat organic matter properties using Rock-Eval 6 pyrolysis within the rooting zones of canopy palms and broadleaved evergreen trees. Mean methane fluxes ranged from 0.56 to 1.2 mg m−2 h−1 and were significantly greater closer to plant stems. In addition, pH, ranging from 3.95 to 4.16, was significantly greater closer to stems. A three pool model of organic matter thermal stability (labile, intermediate and passive pools) indicated a large labile pool in surface peat (35–42%), with equivalent carbon stocks of 2236–3065 g m−2. Methane fluxes were driven by overall substrate availability rather than any specific carbon pool. No peat properties correlated with carbon dioxide fluxes, suggesting a significant role for root respiration, aerobic decomposition and/or methane oxidation. These results demonstrate how vegetation type and inputs, and peat organic matter properties are important determinants of small scale spatial variation of methane fluxes in tropical peatlands that are affected by climate and land use change.

Feasibility of Ivy (Hedra helix) for landscaping in Seoul, Korea

Due to the global warming, Seoul in Korea seems to be plausible to grow evergreen broad-leaved trees over the cold winter. This offers the planting options to create green environment. Thus, it became worth investigating what kinds of evergreen broad-leaved plants could stand in Seoul during the winter. Ivy (Hedera helix) has been chosen in the current study which is a well-known native and ornamental plant in Europe. It grows in warm condition in general. The current study tracked H. helix which is evergreen cover plant over winter in order to evaluate the possibility for utilizing this species as a climber or cover-plant in Seoul. We found that H. helix can survive over the winter and can be utilized to create evergreen environment in Seoul. It also implies that similar kinds of plants could be tested assuming the environment of Seoul is becoming more suitable for the plants originated from the warmer sites. H. helix is an option for elaborating outdoor environments in the city that lacks of green color.

Transcriptome analysis reveals crucial genes involved in the biosynthesis of nervonic acid in woody Malania oleifera oilseeds

BackgroundMalania oleifera Chun et Lee (Olacaceae), an evergreen broad-leaved woody tree native to southwest China, is an important oilseed tree. Its seed oil has a high level of nervonic acid (cis-tetracos-15-enoic acid, over 60%), which is essential for human health. M. oleifera seed oil is a promising source of nervonic acid, but little is known about the physiological and molecular mechanisms underlying its biosynthesis.ResultsIn this study, we recorded oil accumulation at four stages of seed development. Using a high-throughput RNA-sequencing technique, we obtained 55,843 unigenes, of which 29,176 unigenes were functionally annotated. By comparison, 22,833 unigenes had a two-fold or greater expression at the fast oil accumulation stage than at the initial stage. Of these, 198 unigenes were identified as being functionally involved in diverse lipid metabolism processes (including de novo fatty acid synthesis, carbon chain elongation and modification, and triacylglycerol assembly). Key genes (encoding KCS, KCR, HCD and ECR), putatively responsible for nervonic acid biosynthesis, were isolated and their expression profiles during seed development were confirmed by quantitative real-time PCR analysis. Also, we isolated regulatory factors (such as WRI1, ABI3 and FUS3) that are putatively involved in the regulation of oil biosynthesis and seed development.ConclusionOur results provide novel data on the physiological and molecular mechanisms of nervonic acid biosynthesis and oil accumulation in M. oleifera seeds, and will also serve as a starting point for biotechnological genetic engineering for the production of nervonic acid resources.

Low-level summertime isoprene observed at a forested mountaintop site in southern China: implications for strong regional atmospheric oxidative capacity

Abstract. To investigate the atmospheric oxidative capacity (AOC) in forested high mountain areas adjacent to the photochemistry-active Pearl River Delta (PRD) region in southern China, one-month online observations of isoprene and its oxidation products methyl vinyl ketone (MVK) and methacrolein (MACR) were conducted at a national background station in Nanling Mountains in summer 2016. The results showed that the observed daytime isoprene levels (377±46 pptv) were significantly lower in comparison with other forest sites within and outside China, although the sampling site was surrounded with subtropical evergreen broad-leaved trees which are strong isoprene emitters. Also, high daytime (MVK + MACR) ∕ isoprene ratios (1.9±0.5) were observed. Based on the observations, we hypothesized that the lower isoprene levels in the study forest might be attributable to a strong AOC in relation to the elevated regional complex air pollution. In further data analyses, high site-level concentrations of daytime OH (7.3±0.5×106 molecules cm−3) and nighttime NO3 radicals (6.0±0.5×108 molecules cm−3) were estimated by using a photochemical box model incorporating the master chemical mechanism (PBM-MCM), and high regional mixing ratios of OH (19.7±2.3×106 molecules cm−3) during 09:00–15:00 LT were also obtained by applying a parameterization method with measured aromatic hydrocarbons. And besides, high initial mixing ratios (1213±108 pptv) and short atmospheric reaction time (0.27 h) of isoprene during the day were derived by a sequential reaction approach. All these indicate that isoprene was rapidly and highly oxidized in this forest, which supports our hypothesis. The study suggests that the complex air pollution in the PRD may have significantly elevated the background AOC of the adjacent forests, and probably affects the regional air quality and ecological environment in the long term. The feedback of forest ecosystems to the increasing AOC in southern China warrants further studies.

Comparison of allometric equations and biomass expansion factors for six evergreen broad-leaved trees in subtropical forests in southern Korea

ABSTRACTThis study was conducted to compare the allometric equations and biomass expansion factors (BEFs) of six dominant evergreen broad-leaved trees (Camellia japonica L, Castanopsis sieboldii Hatus, Quercus acuta Thunb, Q. glauca Thunb, Machilus thunbergii S. et Z., and Neolitsea sericea Koidz) in subtropical forests. A total of 86 trees were destructively sampled to quantify the aboveground biomass of each tree component (i.e., leaves, branches, and stem). Species-specific or generalized allometric equations and species-dependent BEFs were developed for each tree component of the six broad-leaved forest trees. Species-specific allometric equations were significant (P < 0.05), with the diameter at breast height (DBH) accounting for 68–99% of the variation, whereas generalized allometric equations explained 64–96% of the variation. The values of stem density ranged broadly from 0.49 g cm−3 for C. sieboldii to 0.79 g cm−3 for Q. glauca, with a mean value of 0.68 g cm−3. The BEFs were significantly (P < 0.05) lower for C. sieboldii (1.25) than for M. thunbergii (2.02). Stem density and aboveground BEFs had a significant negative relationship with tree ages. The results indicate that species-specific allometric equations and species-dependent BEFs are applicable for obtaining accurate biomass estimates of subtropical evergreen broad-leaved forests.

Species, size, and location of “giant trees” in Tokyo’s urban area and western suburbs

ABSTRACT The Japanese landscape has been characterised by the occurrence of ancient, massive trees described here as “giant trees”, and many of these have had major historic, cultural, and religious significance. However, modern Japan has experienced significant and rapid urbanisation and in relation to ancient woods and trees, “cultural severance” too. This study identified the species, size, and locations of the giant trees growing in Tokyo’s urban centre and its western suburbs, by conducting field surveys and collecting data from published studies. Classification of sites according to tree girth, with giant trees, revealed six broad locations: (1) forest and agricultural lands of managed secondary and later abandoned woodland with deciduous, broad-leaved trees; (2) public gardens, comprising useful and ornamental plants introduced from southern Japan; (3) parks, including mostly exotic species; (4) shrine sites, including Zelkova serrata, conifers, and evergreen broad-leaved trees; (5) temple sites, including many Torreya nucifera; and (6) Imperial lands, with rare species of trees in low numbers. The highest percentage of giant trees (36%) were found in parks, followed by temple and shrine sites (32%), whereas only 10% were found in other historical places. This study highlights the importance of studying giant tree habitats and history and identifying the relationships between human activities and living trees.

Nurse Effect of the Residual Canopies on the Survival of Evergreen Broadleaved Tree Seedlings Planted in a Coastal Pine Wilt Disease Stand

Nurse Effect of the Residual Canopies on the Survival of Evergreen Broadleaved Tree Seedlings Planted in a Coastal Pine Wilt Disease Stand

First Report of Lasiodiplodia gilanensis Causing Twig and Leaf Blight on Machilus thunbergii in Zhejiang Province of China.

Machilus thunbergii Sieb. et Zucc. (Lauraceae) is a broad-leaved evergreen tree and an endangered species in warm-temperate and subtropical areas of China. It also has high ornamental, timber-use, and soil-conservation functions. In recent years, brown to dark-brown lesions were found on leaves or on twigs of M. thunbergii, which caused decay of the cortex. We first found this disease on about 30% of M. thunbergii trees in April 2017 in Zhejiang Tongling Mountain National Forest Park at Wencheng, Wenzhou, Zhejiang province. Symptomatic material from leaves and stems was surface sterilized in 75% ethanol for 10 s and then in 3% NaClO for 3 min, rinsed three times in sterilized distilled water, dried, transferred onto potato dextrose agar (PDA), and incubated at 25°C. Fourteen pure isolates from symptomatic tissues were obtained by single-spore isolations. These isolates formed colonies with abundant villous aerial hyphae. The colonies initially were gray and then turned to black. The strains had black, scattered, or clustered pycnidia and cylindrical conidiophores that occasionally branched. The conidia of the strains were fusiform, thick walled, 31.2 ± 2.5 μm long, and 16.7 ± 1.5 μm wide (length-to-width ratio = 1.9 ± 0.2), and with obtuse apices tapering to a truncate base. Initially, conidia were single celled and transparent, and then they became double celled and the melanin gradually increased. The morphology was similar to the description of Lasiodiplodia gilanensis Abdollahzadeh, Javadi & A.J.L. Phillips (Abdollahzadeh et al. 2010). Genomic DNA samples of the 14 isolates were extracted using the cetyl trimethylammonium bromide method. The β-tubulin (TB) gene was amplified by polymerase chain reaction assay using primers bt2a/bt2b, and a portion of the translation elongation factor 1-alpha (EF1-α) gene was amplified using primers EF-1-986/EF-728. The amplified DNA fragments were then sequenced, and the sequences of all 14 isolates were identical. The sequences of TB (GenBank accession no. MG372749) and EF1-α (GenBank accession no. MG372751) in the representative strain HNDNYB-1 were 100 and 100% identical to the TB sequence of L. gilanensis strain 3K59 (GenBank accession no. KF955888) and the EF1-α sequence of L. gilanensis strain IRAN1501C (GenBank accession no. GU945341), respectively (Abdollahzadeh et al. 2010; Chen et al. 2014). Morphological and molecular results confirmed the isolate as L. gilanensis. Five isolates were selected for pathogenicity tests. Healthy twigs and leaves of M. thunbergii were collected in the field and wounded with a sterilized needle. A 5-mm-diameter mycelial plug of each isolate was excised from the margin of a 4-day-old colony from a PDA plate and placed to the wounded twigs or leaves, and the twigs and leaves were treated similarly with uncolonized plugs as a control. All plants were maintained in an artificial climate chamber at 25°C and 90% relative humidity with a 12-h photoperiod per day. After 5 days, typical lesions developed on inoculated twigs and leaves, whereas control plants remained asymptomatic. The L. gilanensis strains were only reisolated from inoculated plants, and then they were confirmed via morphological observations and genomic DNA testing as identical to the original inoculated strains. L. gilanensis has previously been isolated on California pistachio and pomegranate (Chen et al. 2014; Urbez-Torres et al. 2016), but to the best of our knowledge, this is the first report of this pathogen on M. thunbergii worldwide.

Approximate Bayesian computation analysis of EST-associated microsatellites indicates that the broadleaved evergreen tree Castanopsis sieboldii survived the Last Glacial Maximum in multiple refugia in Japan.

Climatic changes have played major roles in plants' evolutionary history. Glacial oscillations have been particularly important, but some of their effects on plants' populations are poorly understood, including the numbers and locations of refugia in Asian warm temperate zones. In the present study, we investigated the demographic history of the broadleaved evergreen tree species Castanopsis sieboldii (Fagaceae) during the last glacial period in Japan. We used approximate Bayesian computation (ABC) for model comparison and parameter estimation for the demographic modeling using 27 EST-associated microsatellites. We also performed the species distribution modeling (SDM). The results strongly support a demographic scenario that the Ryukyu Islands and the western parts in the main islands (Kyushu and western Shikoku) were derived from separate refugia and the eastern parts in the main islands and the Japan Sea groups were diverged from the western parts prior to the coldest stage of the Last Glacial Maximum (LGM). Our data indicate that multiple refugia survived at least one in the Ryukyu Islands, and the other three regions of the western and eastern parts and around the Japan Sea of the main islands of Japan during the LGM. The SDM analysis also suggests the potential habitats under LGM climate conditions were mainly located along the Pacific Ocean side of the coastal region. Our ABC-based study helps efforts resolve the demographic history of a dominant species in warm temperate broadleaved forests during and after the last glacial period, which provides a basic model for future phylogeographical studies using this approach.

Environmental changes and human activity since the Neolithic: Evidence from pollen and phytoliths in Hochung, Sai Kung area, Hong Kong

An excavation has revealed in Hochung, in the Sai Kung area of Hong Kong, which mainly deposited during the Middle to Late Neolithic period. Base on pollen and phytolith analysis, and combine with pervious published report reconstructed the paleoenvironmental changes around the archeological site. Results show that the settings around the Hochung site changed from river bank, lagoon to floodplain marsh and finally changed to cultivated land during Middle to Late Holocene. Evidence of pollen and phytoliths, coupled with the excavated relics, revealed that the Neolithic culture was characterized by fishing and hunting at ~4200–3500 yr BP, without evidence of rice cultivation or other agricultural activity in this area. Until the Tang and Song Dynasties, rice cultivation appeared based on pollen and phytolith assemblages, but the area of excavated site was not yet an in situ rice field. During the Ming and Qing dynasties, rice agriculture flourished, and the area turned into a local paddy field, lasting until 1960s. Meanwhile, the gradual reduction of evergreen broad-leaved trees and the increase of pioneer plants such as Dicranopteris and other secondary plants since the Tang and Song dynasties imply that the expansion of human agricultural activity caused serious damage to the natural evergreen broad-leaved forest. In the history period, the agriculture civilization has very closely relationship between the south area and the north area, especially from the Qin Dynasty to present.

Photosynthesis of three evergreen broad-leaved tree species, Castanopsis sieboldii, Quercus glauca, and Q. myrsinaefolia, under elevated ozone

Abstract: The main goal of this study was to obtain detailed information on photosynthetic responses of evergreen broad-leaved tree species to ozone (O3). For this, two-year-old seedlings of Castanopsis sieboldii, Quercus glauca, and Q. myrsinaefolia were grown for one growing season, from 15 May to 27 October 2014 under three levels of gas treatments, charcoal-filtered air and 1.0 time and 1.5 times ambient O3 concentrations. We analysed the intercellular CO2 concentration-response curve of the net photosynthetic rate, i.e., the A/Ci curve, in July and October, and growth measurement was carried out at the end of the experiment in October. We observed a difference in O3 susceptibility among the species. Negative effects of O3 were observed on the growth and photosynthetic traits of C. sieboldii, while no significant effects on these traits were noted in the two Quercus species. The decrease in light-saturated net photosynthetic rate (Asat) of C. sieboldii under elevated O3 was accompanied with a significant decrease in the maximum rate of carboxylation (Vcmax). Decreases of leaf nitrogen content and nitrogen use efficiency to Rubisco are considered as factors contributing to lower Vcmax in C. sieboldii seedlings under elevated O3. In addition to the decrease in Vcmax, O3 exposure induced marginal increase of stomatal limitation of photosynthesis. These results indicate that both biochemical and diffusion processes in photosynthesis are responsible for the decrease in Asat of C. sieboldii under elevated O3.

A paradox of latitudinal leaf defense strategies in deciduous and evergreen broadleaved trees

The classical “low latitude–high defense” hypothesis is seldom supported by empirical evidence. In this context, we tested latitudinal patterns in the leaf defense traits of deciduous broadleaved (DB) and evergreen broadleaved (EGB) tree species, which are expected to affect herbivore diversity. We examined the co-occurrence of leaf defense traits (tannin and phenol content, leaf mechanical strength, leaf dry matter content, leaf mass per area, and leaf thickness) in 741 broadleaved tree species and their correlations with species geographical range in East Asian island flora. We discovered contrasting latitudinal defense strategy gradients in DB and EGB tree species. DB species employed chemical defenses (increasing tannin and phenol content) at higher latitudes and physical defenses (softer and thinner leaves) at lower latitudes, whereas EGB tree species exhibited opposite latitudinal defense patterns. The “low latitude high defense” hypothesis included a paradoxical aspect in chemical and physical defense traits across broadleaved tree species. To reconcile paradoxical defense strategies along the latitudinal gradient, we conclude that interactive correlations among leaf traits are controlled by leaf longevity, which differs between DB and EGB tree species.

Plant community type and site conditions of coastal forests consisting of evergreen broad-leaved tree species in warm temperate zone in south-west Japan

Plant community type and site conditions of coastal forests consisting of evergreen broad-leaved tree species in warm temperate zone in south-west Japan

Environmental conditions for seed germination and seedling growth of Cinnamomum camphora (Lauraceae): the possibility of regeneration in an abandoned deciduous broad-leaved forest, eastern Japan

ABSTRACTCinnamomum camphora is an evergreen broad-leaved tree distributed throughout southeastern China, Taiwan, and southern Japan. This tree has been widely cultivated and utilized by humans since ancient times; therefore, its natural distribution and regeneration are ambiguous. We established a mowing zone and a control zone in an abandoned deciduous broad-leaved forest in eastern Japan. In the mowing zone, an evergreen dwarf bamboo, Pleioblastus chino, and evergreen broad-leaved trees such as Quercus myrsinifolia and Eurya japonica were cut at ground level. We set nine study sites (1 × 1 m quadrats) on the forest floor of these zones, and measured the fraction of absorbed photosynthetically active radiation (fAPAR), soil moisture content, and soil temperature. Overall, 120 seeds of C. camphora were sown at a depth of 1 cm on each site, and seed germination and the survival and growth of seedlings were monitored over 4 years. Seed germination ratios at the sites were negatively affected by fAPAR and soil moisture content and positively affected by daily fluctuation of soil temperature. Seedling survival ratios and heights were negatively affected by fAPAR and positively affected by soil moisture content; no seedlings survived at the control site, and the height of seedlings was significantly higher under the canopy gap. Seeds of C. camphora could germinate in an abandoned secondary forest in eastern Japan, but the dominance of P. chino largely prevented the establishment of seedlings; the presence of a canopy gap, along with consecutive mowing, was considered to be indispensable for regeneration.

A Conformational Isomer of Soulattrolide from the Stem Bark of Calophyllum symingtonianum and Its Antibacterial Activity

Callophylum symingtonianum (Guttiferae), an evergreen broad-leaved tree that usually grows in hill forests, can be found distributed in the Malay Peninsula. The barks, leaves, flowers and seeds is often used medicinally to treat diarrhea and rheumatism. In the present study, we isolated two inophyllum type coumarins, 12-O-ethylinophyllum D (1) and iso-soulattrolide (2) from the stembarks of C. symingtonianum together with their antibacterial activity. The compounds were isolated by chromatographic methods on a silica gel. The structures were established by spectroscopic methods including UV, IR, (1D and 2D) NMR and mass spectrometry as well as by comparison with several literature sources. The antibacterial activity of those compounds was tested using a disc-diffusion assay against Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa. Both compound exhibited mild inhibition against P. aeruginosa with both 111 µg/ml MIC value. Compound 2 also inhibits S. aureus with 25 µg/ml MIC value.

Impact of environmental factors on the decoupling coefficient and the estimation of canopy stomatal conductance for ever-green broad-leaved tree species

Impact of environmental factors on the decoupling coefficient and the estimation of canopy stomatal conductance for ever-green broad-leaved tree species

Root exudate analogues accelerate CO2 and CH4 production in tropical peat

Root exudates represent a large and labile carbon input in tropical peatlands, but their contribution to carbon dioxide (CO2) and methane (CH4) production remains poorly understood. Changes in species composition and productivity of peatland plant communities in response to global change could alter both inputs of exudates and associated greenhouse gas emissions. We used manipulative laboratory incubations to assess the extent to which root exudate quantity and chemical composition drives greenhouse gas emissions from tropical peatlands. Peat was sampled from beneath canopy palms (Raphia taedigera) and broadleaved evergreen trees (Campnosperma panamensis) in an ombrotrophic wetland in Panama. Root exudate analogues comprising a mixture of sugars and organic acids were added in solution to peats derived from both species, with CO2 and CH4 measured over time. CO2 and CH4 production increased under most treatments, but the magnitude and duration of the response depended on the composition of the added labile carbon mixture rather than the quantity of carbon added or the botanical origin of the peat. Treatments containing organic acids increased soil pH and altered other soil properties including redox potential but did not affect the activities of extracellular hydrolytic enzymes. CO2 but not CH4 production was found to be linearly related to microbial activity and redox potential. Our findings demonstrate the importance of root exudate composition in regulating greenhouse gas fluxes and propose that in situ plant species changes, particularly those associated with land use change, may account for small scale spatial variation in CO2 and CH4 fluxes due to species specific root exudate compositions.