Zelkova Serrata Research Articles

Assessment of Broad-Leaved Forest Stand Management

There are many broad-leaved forests in Japan that were formerly managed for charcoal production, which have been abandoned for decades. Appropriate thinning can revitalize these forests if the cost balance of the management is positive. Two critical elements are the construction of spur roads to facilitate mechanized harvesting operations and management planning that considers stand properties such as the growing stock, species, and tree size distribution. We surveyed three abandoned former broad-leaved coppice stands; one coastal, one cool temperate and one warm temperate. The stock in all three stands exceeded 300 m3 ha-1, two- to three-fold the official forest registry data estimates. The dominant species in terms of tree numbers are Castanopsis sieboldii, Pieris japonica, and Quercus glauca. Medium-sized trees involve those well suited for firewood, i.e., Quercus acuta, Quercus glauca, Quercus serrata, etc. Each plot contained a few large trees that potentially have a high market value, e.g., Cinnamomum camphora, Zelkova serrata, Abies firma, etc. The average income from harvested trees was estimated to be 10200 JPY (Japanese Yen) m-3, whereas the thinning costs would be 3200 to 5400 JPY m-3, with the additional spur road construction costs. The management cost balance of a broad-leaved stand in a 60 year rotation was evaluated with both Net Present Value (NPV) (for interest rates of 1, 2, 3, and 4%) and Internal Rate of Return (IRR). This balance was compared with that of a typical plantation stand of Japanese cedar (Cryptomeria japonica) and of a fast-growing plantation stand of Chinese fir (Cunninghamia lanceolata). The estimated NPVs were largest for the fast-growing plantation stand, second largest for the typical plantation stand, and lowest for the broad-leaved stand with a NPV interest rate of 1 + %. However, the IRR of the broad-leaved stand was the highest, followed by that of the fast-growing plantation stand, while the IRR of the typical plantation stand was the lowest. This order was the same for NPVs assuming higher interest rates. 1 JPY=0.0086 € on April 29, 2019.

The effects of tree characteristics on rainfall interception in urban areas

Trees in urban areas have significant effects on the urban ecosystem. They can be used to improve the water cycle in urban areas by increasing evaporation and reducing runoff through rainfall interception. Street trees placed in planters on impervious areas reduce runoff by intercepting rainfall and by temporarily storing raindrops on leaves. Therefore, understanding tree canopy geometry and the effect of rainfall interception is important in urban hydrology. In this study, we assessed the effect of tree canopy morphology on rainfall interception using four major street tree species, Sophora japonica L., Ginkgo biloba L., Zelkova serrata (Thunb.) Makino, and Aesculus turbinata Blume, in Seoul, South Korea. We measured throughfall for each tree and also derived three-dimensional data of tree canopy morphology with a terrestrial laser scanner. Tree height, canopy crown width, leaf area index (LAI), leaf area density, mean leaf area, and mean leaf angle were used to determine canopy morphology. The interception rate was mostly affected by the LAI; a higher LAI tended to result in a higher interception rate. Leaf area affected the rainfall interception rate when trees had similar LAIs. These findings on individual tree canopy rainfall interception can help us to understand the importance of rainfall interception in hydrology and for ecological restoration when planning urban green spaces.

Evaluating multiple bioclimatic risks using Bayesian belief network to support urban tree management under climate change

Understanding the vulnerability of trees affected by climate change is a key requirement for identifying management priorities and suggesting suitable urban tree species. To measure such vulnerability under changing climate conditions, indicators of bioclimatic characteristics should be identified and evaluated using past and current geographic growth ranges. However, although climate events often occur simultaneously (e.g., frost and drought), and management issues in this regard need to be clarified, it is challenging to consider multiple risks in a climate change vulnerability assessment. Therefore, we applied a Bayesian belief network (BBN) to interlink the bioclimatic requirements of species and seasonal climate risk of the study site to comprehensively assess the multiple risks. In particular, we integrated expert knowledge and supporting evidences from relevant studies to construct the BBN. The developed BBN revealed vulnerability to frost considering occurrences of cascading and co-occurring climatic risks such as warmer winters and droughts throughout the phenological cycle. As a case study, two tree species, Zelkova serrata and Camellia japonica from Seoul, Republic of Korea, were evaluated. Among the climatic risks considered, the BBN revealed that shortened frost hardening and the occurrence of spring frost right after an extraordinarily warm winter would mainly affect vulnerability to frost of the two species. In particular, C. japonica had high vulnerability due to its high susceptibility to coldness, though growing temperature will be perfectly satisfied under climate change. Generally, this study provides insights to consider multiple bioclimatic risks for guiding urban tree management under climate change.

Arbuscular Mycorrhizal Fungi Associated with Tree Species in a Planted Forest of Eastern China

Arbuscular mycorrhizal fungi (AMF) play an important role in the establishment and maintenance of plant communities in forest ecosystems. Most previous studies about AMF have been conducted in natural forests, and little attention has been paid to trees in planted forests. This study investigated AMF associated with tree species and the relationships between edaphic factors and AMF communities in a planted forest of eastern China. We found high total AMF colonization rates in the roots of Carya illinoensis (Wangenh.) K. Koch, Zelkova serrata (Thunb.) Makinoz, Taxodium ‘zhongshansha’, Eucommia ulmoides Oliv., and Elaeagnus pungens Thunb., ranging from 62.07% to 100%, indicating that AMF can establish effective symbiotic relationships with these tree species. The AMF colonization rate was significantly and negatively correlated with soil phosphorus, while AMF colonization intensity was significantly and negatively correlated with soil moisture content, total carbon, and organic matter content. Spore density was in the range of 4.38 to 76.38 spores per g soil. In total, 35 AMF species from 10 genera were identified. Glomus and Acaulospora were the dominant genera. Acaulospora foveata and Septoglomus constrictum were the dominant species. AMF communities differed among the tree species and were closely related to edaphic factors, and AMF diversity was significantly related to soil carbon and pH. Our results revealed the colonization, community, and diversity of AMF associated with tree species, as well as their relationships with edaphic factors, in planted forests. Our findings can be used to provide insight on the utilization and management of AMF to maintain sustainable management of planted forests.

Precipitation on abscised leaves modulates leaf‐mining beetle (Trachys yanoi) survivorship and population dynamics

1. We clarified the effects of early leaf abscission on the survivorship of the leaf‐mining beetle Trachys yanoi Y. Kurosawa (Coleoptera: Buprestidae) and the underlying mechanism in relation to weather conditions in Japan. Trachys yanoi is an insect pest of zelkova trees [Zelkova serrata (Thunb.) Makino (Rosales: Ulmaceae)]. Larvae burrow into zelkova leaves and feed on leaf tissue, causing early leaf abscission.2. This study investigated the relationship between the beetle population and weather conditions over 10 years in a zelkova forest. The effects of moisture and temperature on adult emergence from early abscised leaves were examined in the laboratory and in the field.3. The beetle population in the studied forest was negatively affected by high precipitation levels when the beetles still inhabited early abscised leaves. Fewer adults emerged from early abscised leaves under wet conditions than under dry conditions, in both laboratory and field tests.4. These results demonstrate that early leaf abscission plays an important role in leaf‐mining beetle survivorship and population dynamics, and that the amount of precipitation when leaf‐mining beetles still inhabit early abscised leaves modulates this effect.5. Because precipitation when leaf‐mining beetles still inhabit early abscised leaves was mainly driven by an East Asian rainy season front, the beetle population dynamics were affected by the activity of the front.

Spatial distribution of vegetation along the environmental gradient on the coastal cliff and plateau of Janggi peninsula (Homigot), southeastern Korea

BackgroundCliffs are a major plant habitat around the coastal area, but in contrast to sand dunes and salt marshes, they have been little investigated in Korea. There are simple descriptions of cliff vegetation in studies on island vegetation, but there is no published paper, which addressed sea cliff vegetation synthetically. Furthermore, the coastal area where this study was carried out was designated as a conservation reserve. Even though, this area is exposed to intense recreational use such as trekking in these days.This study aims to clarify spatial distribution and structure of vegetation along the environmental gradient on coastal cliff and plateau in the Janggi peninsula (Homigot) located on southeastern Korea. Further, this study has also another objective to prepare a restoration plan to protect this conservation reserve from intense human disturbance.ResultsLandscape elements were arranged in the order of sea cliff risen directly on the sea, seashore, coastal cliff, and plateau covered with relatively deep soil in a coastal area of the Janggi peninsula (Homigot), southeastern Korea. Vegetation was sampled at 59 plots arranged from the sea cliff through the seashore and coastal cliff to plateau. The sea cliff, seashore, and coastal cliff, which compose the coastal landscape, were dominated by the seashore spatulate aster (Aster spathulifolius Maxim.) community, dwarf sand sedge (Carex pumila Thunb.) community, and seashore spatulate aster (Aster spathulifolius Maxim.) community. On the plateau corresponding to the ridge of the coastal cliff, black pine (Pinus thunbergii Parl.) community, golden rain tree (Koelreuteria paniculata Laxmann) community, east Asian hackberry (Celtis sinensis Pers.) community, sawleaf zelkova (Zelkova serrata Makino) community, and Korean oak (Quercus dentata Thunb.) community were established in the mentioned order along distance from the sea. Stand ordination showed a vegetation sequence from the seashore through the cliff to the plateau, consistent in its overall pattern among sites. This was dominated by topography. There is evidence for the importance also of salinity, drought and of soil depth.ConclusionThe lack of scientific interest in cliffs to date is in striking contrast to the commonness of cliffs around the whole national territory and to the attraction cliffs have had for humans throughout history. Cliffs provide a unique habitat, rarely investigated from an ecological viewpoint. Cliffs may represent an invaluable type of ecosystem, consisting of some of the least disturbed habitats on earth and contributing more to the biodiversity of a region than their surface coverage would indicate. Although this coastal area where this study was carried out was designated as a conservation reserve, this area is in danger of severe disturbance due to excessive recreational use. We recommended a restoration plan to protect this area from such a disturbance.

Remnant pattern of woods and scattered trees of <i>Celtis sinensis, Aphananthe asper</i>a and <i>Zelkova serrata</i> in the urban area of Kyoto for 30 years

In the urban area of Kyoto, woods and scattered trees of Celtis sinensis, Aphananthe aspera and Zelkova serrata with historical and cultural value aregrowing, but they have been decreasing due to urbanization. In this research, GIS analysis was conducted based on the information about detailed distribution survey in 1986 to clarify the habitat that needs to be considered for the conservation.As a result, the following facts were revealed.First, woods were divided and shrunk in the temples, not only for development aimed at the role played by temples such as cemeteries but also for development to enhance the accessibility of touristic implications such as parking lots. Second, scattered trees have been largely lost in residential areas, commercial lands, and public lands, mainly because of urbanization. In the residential areas, in addition, cutting scattered trees seems to have occurred due to the loss of spatial margin that affects the consciousness of landowners. Finally, woods and scattered trees were preserved in large-scale parks and buffer areas such as riverside and the foot of mountainsthat are not developed.In conclusion, it is necessary for the conservationto preserve spaces in declining trend and to create habitable environments in preserved spaces.

Effects of Arbuscular Mycorrhizal Fungi on Growth, Photosynthesis, and Nutrient Uptake of Zelkova serrata (Thunb.) Makino Seedlings under Salt Stress

Salinity is the primary restriction factor for vegetation conservation and the rehabilitation of coastal areas in Eastern China. Arbuscular mycorrhizal fungi (AMF) have been proved to have the ability to alleviate salt stress in plants. However, the role of AMF in relieving salt stress among indigenous trees species is less well known, limiting the application of AMF in the afforestation of local area. In this study, a salt-stress pot experiment was conducted to evaluate the effects of AMF on Zelkova serrata (Thunb.) Makino, a tree species with significant potential for afforestation of coastal area. The Z. serrata seedlings inoculated with three AMF strains (Funneliformis mosseae 1, Funneliformis mosseae 2, and Diversispora tortuosa) were subjected to two salt treatments (0 and 100 mM NaCl) under greenhouse conditions. The results showed that the three AMF strains had positive effects, to a certain extent, on plant growth and photosynthesis under normal condition. However, only F. mosseae 1 and F. mosseae 2 alleviated the inhibition of growth, photosynthesis, and nutrient uptake of Z. serrata seedlings under salt stress. The two AMF strains mitigated salt-induced adverse effects on seedlings mainly by increasing the leaf photosynthetic ability and biomass accumulation by reducing Na+ content, increasing P, K+, and Mg2+ content, as well as by enhancing photosynthetic pigments content and the stomatal conductance of leaves. These results indicated that AMF inoculation is a promising strategy for the afforestation of coastal areas in Eastern China.

도시근린공원 리뉴얼을 위한 식재디자인 연구† - 경기도 시흥시 옥구공원을 대상으로 -

This paper aims to identify planting design for the renewal of Okgu Park, located in Siheung, Gyeonggi-do. I designate planting concept fit spatial functions and also suggest planting designs that are proper for a growth environment. The spatial functions of the research site are divided on the basis of the park facilities, its surroundings, and usage. To understand the planting concept, this paper looks into the distribution of plant species and the precise planting structure. To understand the planting concept and the current usage of shade space in the park, I examine the distribution of plant species and the precise planting structure. There are 48 kinds of plants, with <italic>Zoysia japonica</italic> area (28.84%), <italic>Prunus yedoensis</italic> (8.0%), <italic>Pinus thunbergii</italic> (6.73%) and <italic>Zelkova serrata</italic> (6.38%) taking up the majority. 27 places were chosen for researching the precise planting structure. The research shows that the average green coverage ratio is 38.14% and the average green capacity coefficient is 0.72m³/m². The growth defective rate of trees in the shade areas is estimated by averaging the classified growth conditions of individual trees per block of shade areas. Areas with an inferior environment for growth and low spatial usage in Okgu Park are selected as subjects for planting design. After comparing the spatial functions with planting concepts and analyzing the growth of plants, I identify 36,236m² areas with inferior growth condition. I also examine structures and the surrounding areas to find areas that require urgent planting improvement, specifically identifying landscape space and shade space around the fountain and the buffer space nearby the North gate. I rearrange spatial functions in the selected areas to devise a planting design considering the existing vegetation, layer structure, and its usage. I set the planting concept and direction to improve the landscape of the selected areas through implementing a planting design so the park users can be satisfied with each space.

The chloroplast genome of a landscape tree Zelkova serrata (Ulmaceae)

We reported the complete chloroplast genome for Zelkova serrata, the first in the distinctive genus Zelkova to be sequenced in the family Ulmaceae. The plastome is totally 158,495 bp in length, containing a pair of inverted repeats (IRs), a large single-copy region (LSR) and a small single-copy region (SSR), which are 26,456 bp, 86,921 bp and 18,684 bp, respectively. A total of 103 unique genes were identified in Z. serrata chloroplast genome, of which 88 are single-copy genes, while15 are duplicated in IR regions. Further, maximum-likelihood phylogenetic analyses were conducted using eight complete plastomes of the Ulmaceae, which support close relationships between Z. serrata, Ulmus gaussenii, and U. chenmoui.

Verifying the Possibility of Investigating Tree Ages Using Resistograph

This study aims to determine the ideal feed speed of a resistograph to evaluate the number of tree rings in several tree species. The needle speed was fixed at 1,500 r/min. Herein, various tree species, such as Pseudotsuga menziesii, Pinus koraiensis, Abies holophylla, and Zelkova serrata, were considered for experiments. Results showed that the most proper feed speed for Zelkova serrata, Larix kaempferi, Pseudotsuga menziesii, Abies holophylla, and Pinus koraiensis was 75, 100, 100, 150, and 175 cm/min, respectively. However, in all the cases, the electric resistance values of tree ring narrower than 1 mm were not suitable for determining tree-ring boundaries. Upon comparing the inter-annual time series of ring widths and electric resistance values of resistograph, a meaningful synchronization was verified. If resistograph would be improved to the extent that it can measure tree rings narrower than 1 mm, it can replace the conventional method used for counting the number of tree rings in the increment cores. Additionally, it can also be used to investigate the tree growth.

Variance components and parent–offspring cor- relations of growth traits vary among the initial planting spacings in Zelkova serrata

Abstract Variance components of tree height (HT) and stem diameter at 1.3 m above the ground (DBH) were investigated for the eight open-pollinated families of Zelkova serrata (Thumb.) Makino planted with three different initial planting spacings in a progeny test site, Chiba, Japan. Parent–offspring correlations were also evaluated by using these families and their mother trees. The smallest values of HT and DBH were observed in the narrowest initial planting spacing (1.10 x 1.10 m) compared to those in medium (1.30 x 1.36 m) and wide (2.00 x 1.80 m) spacings, suggesting that adverse effects of competition with neighboring trees occurred on both height and radial growth. Similar to HT and DBH, the initial planting spacings also affected the genetic parameter estimates: the ratio of family variance component to total phenotypic variance showed the highest value in narrow initial planting spacing for both HT and DBH. Thus, family variance component might include competition effects, leading to biased genetic parameter estimates. In contrast, parent–offspring correlation coefficients showed the highest value in wide initial planting spacing where competition effect might be smaller. Therefore, the growth traits of Z. serrata might be inherited from the parent to the offspring when competition effect was small.

Effects of Tree Root Density on Soil Total Porosity and Non-Capillary Porosity Using a Ground-Penetrating Tree Radar Unit in Shanghai, China

To explore the relationship between arbor root density and corresponding physical soil properties (total porosity, non-capillary porosity, specific weight, bulk density, moisture content, and permeability), noninvasive methods such as Tree Radar Unit (TRU) were utilized to detect the root systems of 10 species of tree that are commonly used in Shanghai green spaces with more than 70% frequency of occurrence. Using TRU and soil investigation, root density and soil porous features were determined for different tree species, depth slices, and distances. The relationships among root density, soil porosity, and non-capillary porosity were identified using variance analysis and regression analysis. The results indicated that root density decreased with increasing distance from the trunk and soil depth. Soil porosity and non-capillary porosity had significantly positive and linear correlations with root density. Compared with lawns, trees such as Zelkova serrata, Koelreuteria paniculata, Cinnamomum camphora, and Metasequoia glyptostroboides had the greatest effects on soil improvement through soil porosity and non-capillary porosity. Due to the spatial distribution of root systems, trees could be divided into three types based on their influence at various soil depths.

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

ABSTRACTThe 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.

Micropropagation of Mespilus germanica L.

The data presented in this paper is supporting the research article “Variable seed behavior increases recruitment success of a hardwood tree, Zelkova serrata, in spatially heterogeneous forest environments” (Oyama et al., 2018) [1]. We provided the data of several ecological properties of the two types of the seeds (i.e. shoot seeds vs. single seeds) with distinctly different dispersal behaviors. We provide data of terminal velocity, which was measured by releasing 50 replicates of each seed type from a height of 5.0 m in dead air space in a gymnasium. We also show the data of germination cue [i.e. red:far-red (R:FR) ratios], which was examined in plant growth chambers that received three distinct R:FR ratios (0.1, 0.4, and 1.0; 16 h photoperiod) or no illumination. Further, we show the data of the rates of multi-locus outcrossing rates and biparental inbreeding in each of single- and shoot seeds. The mating system parameters were estimated by assaying a total of 80 shoot seeds and 70 single seeds that were randomly collected from Parent 1 and Parent 2 for five microsatellite loci. Finally, we show the data of hemispherical canopy photographs, which were taken at different distance from the adults using a digital camera equipped with a fisheye lens.

Strategy for Screening of Antioxidant Compounds from Two Ulmaceae Species Based on Liquid Chromatography-Mass Spectrometry.

Liquid chromatography-mass spectrometry (LC-MS)-based untargeted metabolomics implies that annotated metabolites can serve as potential markers of the associated bioactivities of plant extracts. Firstly, we selected Aphananthe aspera and Zelkova serrata (Family: Ulmaceae) from 16 Korean plant species based on their distinct principal component analysis (PCA) patterns in LC-MS datasets and antioxidant activity assays. Further, we chose 40% solid-phase extraction (SPE) extracts of the two species displaying the highest antioxidant activities coupled with distinct PCA patterns. Examining the metabolite compositions of the 40% SPE extracts, we observed relatively higher abundances of quercetin, kaempferol, and isorhamnetin O-glucosides for A. aspera, whereas quercetin, isorhamnetin O-glucuronides, and procyanidin dimer were relatively higher in Z. serrata. These metabolites were clearly distinguished in pathway map and displayed strong positive correlations with antioxidant activity. Further, we performed preparative high-performance liquid chromatography (prep-HPLC) analysis coupled with the 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) assay to validate their functional correlations. As a result, quercetin O-sophoroside was determined as the main antioxidant in A. aspera, while isorhamnetin O-glucuronide and procyanidin dimer were the primary antioxidants in Z. serrata. The current study suggests that the LC-MS-based untargeted metabolomics strategy can be used to illuminate subtle metabolic disparities as well as compounds associated with bioactivities.

Volumetric equation development and carbon storage estimation of urban forest in Daejeon, Korea

ABSTRACTThis study was performed to develop equations which are suitable for estimating carbon storage of urban forest in Daejeon, Korea and to evaluate carbon storage and sequestration of urban forest using developed equations. Among the urban forest, we only concern about the major street tree species (Platanus occidentalis, Ginko biloba, Zelkova serrata, Chionanthus retusa, and Acer pseudo-sieboldianum) which are planted alongside a road for vehicles as well as pedestrian in urban area. Developed equations showed R2 of 0.93 (Z. serrata), 0.67 (P. occidentalis), 0.96 (G. biloba), 0.93 (C. retusa), and 0.88 (A. pseudo-sieboldianum) when they were derived from diameter at breath height (DBH). Using the DBH-volume equation, the five street tree species (P. occidentalis, G. biloba, Z. serrata, C. retusa, and A. pseudo-sieboldianum), which account for 70% of total street trees in the Daejeon, stored about 4290 tons of carbon. Among the five street tree species, P. occidentalis constituted more than 50% of total stored carbon and followed by G. biloba. Based on the carbon storage, five street tree species can sequestrate 216 tons of carbon annually which means that 793 tons of carbon dioxide (CO2) removal from the air every year.

Variable seed behavior increases recruitment success of a hardwood tree, Zelkova serrata, in spatially heterogeneous forest environments

Abstract Variable seed behavior (e.g., seed heteromorphism) plays an important role in enhancing plant fitness by spreading risk in spatially and temporally changing environments. This adaptation is common in herbs but rare in trees. Zelkova serrata, one of the most important commercial tree species in Japan, has two types of seeds: shoot seeds that disperse via a seed-bearing shoot and single seeds that disseminate after separating from shoots. To evaluate whether the seeds of Z. serrata show heteromorphism, we compared several inherent ecological properties (e.g., seed mass, degree of seed dormancy, and dispersal ability) between the two seed types and assessed the effects of variable seed behavior on recruitment success in forest environments. The degree of seed dormancy did not differ between the two seed types. Seed mass increased with a delayed seed dispersal time but did not differ between the two types at any time. Seed dispersal ability was greater in shoot seeds than in single seeds. These inherent seed behaviors suggest that the two types of seeds do not reflect seed heteromorphism. The results, however, indicate that shoot seeds dispersed larger seeds over much greater distances than did single seeds, particularly at later seed dispersal times, whereas a greater number of single seeds were disseminated near adults. To evaluate the effects of variable seed dispersal ability on seedling establishment in forest environments, we measured seedling performance at different distances (≤27.5 m) from adults isolated from one another in the forest understory. Seedling density, survival, and growth did not vary with distance from adults (i.e., there was little negative distance-dependent seedling mortality), which suggests that single seeds can contribute to persistent seedling banks near conspecific adults. To evaluate the advantages of long-distance dispersal of shoot seeds for recruitment on disturbed sites (i.e., gaps), we compared the occurrence and relative abundance of Z. serrata among 1100 plots with different slopes; steep slopes are closely associated with gap creation (e.g., landslides). The occurrence and relative abundance of Z. serrata increased with slope inclination, which suggests that shoot seeds may enhance recruitment success in disturbed sites along steep slopes, thereby generating Z. serrata-dominated forests. This suggests that the variability in seed behavior of Z. serrata may enhance recruitment success in spatially heterogeneous forest environments. Knowledge of the unique reproductive behaviors and the wide range of habitats suitable for this species is important for forest managers when making sustainable timber production plans for Z. serrata.

帯状更新地におけるケヤキ,スギ,ヒノキの成長 : 植栽から9年目および11年目の結果

帯状更新地におけるケヤキ,スギ,ヒノキの成長 : 植栽から9年目および11年目の結果

Comparison of artificial cavities in woods of Japanese zelkova (Zelkova serrata) and Japanese red pine (Pinus densiflora) with four kinds of decay diagnostic instruments

Comparison of artificial cavities in woods of Japanese zelkova (<i>Zelkova serrata</i>) and Japanese red pine (<i>Pinus densiflora</i>) with four kinds of decay diagnostic instruments