Subtree Layer Research Articles

The natural habitat and distribution of Echinosophora koreensis(Nakai) Nakai in Korea

The distribution and habitat characteristics of Echinosophora koreensis (Nakai) Nakai were investigated to compile basic data for conservation and restoration. The species Echinosophora koreensis is distributed within fourteen regions of the Korean Province of Gangwon, including Yanggu-gun, Inje-gun, Cheorwon-gun, Chuncheon-si and Hongcheon-gun. Natural habitats were located at altitudes of 192-626 m, with inclinations of 1-. One hundred and fifty seven vascular plant taxa were identified from 42 quadrats in 14 habitats. Dominant species among the woody plants, based on importance value, were Pinus densiflora and Quercus dentata in the tree (T1) layer, Quercus variabilis, Pinus densiflora and Quercus mongolica in subtree (T2) layer, and Fraxinus rhynchophylla, Prunus sargentii, Zanthoxylum schinifilium, and Ulmus davidiana var. japonica in the shrub (S) layer. Importance values for members of the herb layer were: Echinosophora koreensis 28.34%; Polygonatum odoratum var. pluriflorum 10.21%; Spodiopogon sibiricus 7.60%; Atractylodes ovata 4.77% and Carex lanceolata 4.13%. The importance values of the last four species were high, so they were at affinity with Echinosophora koreensis in their habitats. Average species diversity was 1.03, and evenness and dominance were found to be 0.82 and 0.16, respectively. The soil types were sandy loam and loam. Average field capacity was 13.28%, and the organic matter and soil pH were 6.70% and 5.77, respectively.

자생완도 호랑가시나무 자생지의 생태학적 특성

This study was conducted to analysis the ecological characteristics of "Wando HolIy"<TEX>$(llex{\times}wandoensis)$</TEX> which is expecting as a possible ornamental tree with its beautiful leaves, flowers and fruits, and to find special breeding material which have particular characteristics and also provide correct environmental information which are required for commercial cultivation. The hill of Galmoon-Ri, Gunoei-Myon, Jeonnam Province, Korea, were reported as a original habitat of native <TEX>$llex{\times}wandoensis$</TEX>. The investigation shows that soil pH of native habitat was 6.18, hardness was 2.39, humidity was 38.6%, direction of slope is SSW, and average inclination was <TEX>$15^{\circ}</TEX>. The vegetation around <TEX>$I.{\times}wandoensis$</TEX> is occupied by trees like an Quercus variabilis, Q. serrata, Q. acuta and so on. These are mixed forest of deciduous trees. Tree height reached up to about 12m and its coverage is about 30%. Q. salicina, Camellia japonica, I. integra, Cryptomeria japonica account for sub-tree layer. Tree height is around 8m and coverage is about 20%. Shrub layer was taken by Viburnum furcatum, Callicarpa japonica, Styrax japonica, Eurya japonica, Lindera obtusiloba, Ligustrum japonicum, Smilax china, Cornus walteri etc. Tree height reaches around l.2m and coverage is around 20%. Herb layer includes Trachelospermum asiaticum var. intermedium, Cymbidium goeringii, Dryopteris bissetiana, Disporum viridescens, Disporum smilacinum, Sasa borealis var. gracilis etc. Trachelospermum asiaticum var. intermedium, which are observed in southern evergreen zone, are dominant and its coverage is around 20%. The native habitat was in spoiled condition because of artificial thin out.

금원산 자연휴양림 산림식생의 종 조성

본 연구는 금원산 자연휴양림 산림식생의 층위별 종 조성을 파악하여 산림자원 관리에 필요한 기초자료를 제공할 목적으로 수행되었다. 금원산 자연휴양림의 교목층과 아교목층은 각각 27종과 44종으로 이루어져 있는 것으로 분석되었다. 층위별 중요치는 교목층의 경우 신갈나무와 졸참나무가 가장 높았으며, 아교목층은 당단풍의 중요치가 가장 높은 것으로 나타났다. 관목층과 초본층의 출현수종은 71종과 69종으로 각각 조사되었다. 종다양도와 균재도는 <TEX>$1.0391\sim1.5403$</TEX> <TEX>$0.7259\sim0.8320$</TEX>로 각각 분석되었다. 층위별 우점도는 교목층 0.2741, 아교목층 0.2440, 관목층 0.1680, 초본층 0.1702로 금원산 자연휴양림은 전층에서 다수의 종이 우점하고 있는 것으로 나타났다. 금원산 자연휴양림의 식생구조 분석 결과는 향후 산림자원의 생태적 관리방안을 마련하는데 기초정보로 활용될 수 있을 것이다. The objective of this study were to offer a basis data for application of management of forest resources through grasping of species composition by layer of forest vegetation in the Mt. Geumwon recreational forest. The tree and subtree layer consisted of 27 and 44 species in Mt. Geumwon recreational forest respectively. The importance value of Quercus mongolica (57.1) and Q. serrata (40.4) were highest in the tree layer and that of Acer pseudo-sieboldianum (43.4) was highest in the subtree layer, respectively. The shrub and herb layer was composed of 71 and 69 species, respectively. The value of species diversity ranged from 1.0391 to 1.5403. Evenness ranged from 0.7259 to 0.8320. Dominance was 0.2741 at tree layer, 0.2440 at subtree layer, 0.1680 at shrub layer, and 0.1702 at herb layer, which showed that Mt. Geumwon recreational forest is dominated by a large number of species at all layer. The result of forest vegetation in Mt. Geumwon recreational forest may be utilized as a basic data for application of reasonable ecological management of forest resources.

Biocycle of nitrogen in a Cyclobalanopsis glauca-dominated evergreen broad-leaved forest in East China

The nitrogen (N) cycling was elucidated in a 40-year-old subtropical evergreen broad-leaved forest dominated by Cyclobalanopsis glauca growing on red soil in Zhejiang Province, East China. The concentrations of N in the representative species ranged from 0.49% to 1.64%, the order of which in various layers was liana and herb layers > understory layer > tree and subtree layers; in various organs was leaf > branch > root > trunk; and aboveground parts > underground parts. The sequence of the concentrations of N in C. glauca was understory > tree > subtree layer; young and high-growing > old organs; reproductive > vegetative organs. Seasonal dynamics of the concentrations of N in C. glauca in the tree and subtree layers was comparatively stable. It was lower in autumn (October) in root, branch, and leaf in the tree layer, and low in January in the understory. There was no evident change in regularity of the concentrations of N in varying diameter classes. The concentrations of N in the litterfall, precipitation, throughfall, litter layer, and soil were 0.74%–2.30%, 0.000,038%, 0.000,09%, 1.94%, and 0.59%, respectively. The standing crop of N in the plant community was 1,025.28 kg/hm2, accumulation in the litter layer was 224.88 kg/hm2, and reserve in the soil was 55,151 kg/hm2. Annual retention of N was 119.47 kg/hm2, return was about 84.13 kg/hm2, among which litterfall was 78.49 kg/hm2 and throughfall, 5.64 kg/hm2. Annual absorption of N was 203.60 kg/hm2. Annual input of N through incident precipitation was 4.88 kg/hm2. Compared with other forest types, cycling rate of N in the community was lower than in deciduous broad-leaved forests, rain forests, and mangroves, and was moderate in evergreen broad-leaved forests. N use efficiency of this forest was moderate among the forest types cited. According to the characteristics of the biocycle of phosphorous, it was concluded that N availability in the soil of this forest was not lower, and phosphorous not N was the limiting factor in the growth of plants in this community.

落葉前後に観測した航空機レーザスキャナによるＤＳＭを用いた落葉広葉樹林内の階層構造の把握

In this study, we calculated the difference quantity of the DSM of before defoliation, while defoliation, and after defoliation using time series airborne laser scanner, and we tried to estimate the stratification in deciduous broadleaved forest by grasp of the growth and the covering situation of subtree layer, shrub layer, and herb layer from the amount of change of DSM. The target area of this study was set to Zelkova serrata forest and cherry forest (Prunus yedoensis etc.) in Tama Forest Science Garden. As a result, it was able to be divided 4 stratification types that deciduous broadleaved tree layer in which the understory vegetation does not develop, deciduous broadleaved tree layer in which shrub layer and herb layer develop, deciduous broadleaved tree layer in which subtree layer and shrub of evergreen broadleaved tree develop, and evergreen broadleaved tree layer (Quercus glauca mainly) .

Vegetation and flora of Hibiscus hamabo inhabited naturally in Soan Island

Hibiscus hamabo, called "Hwang-geun", growing about 3m in height is a deciduous shrub or subtree of Malvaceae. Because the number of these species is very limited in the world, the Ministry of Environment has designated H. hamabo as a preserved plant. The Korea Forest Service also protects it strictly by law since H. hamabo is an out-of-the-way plant and possibly may be exterminated soon in Korea. Investigation for distribution and ecological characteristics of the habitat for H. hamabo was carried out on Soan Island. Two wild H. hamabo were found at the forest edge (equation omitted) along the sea coast located in the southern part of Soan Island and this was the first report in the Korean academic world. These two wild H. hamabos were growing in a naturally inhibited area. The diameters at the base were 12cm and 15cm. The Tree heights were 150cm and 210cm and the number of branches of each wild H. hamabo was 4 and 7. However, the present condition of these plants was not good. Environmental conditions of the naturally inhibited area of H. hamabo were very mild because it is located at the edge of the forest and is always sunny during the daytime since the slope of the inhibited area is facing South. The ground drained very well since the soil was made of gravels and sand. Because the percent of vegetation of the subtree layer where H. hamabo was growing was 40%, the cover degree and sociability of flex crenata trees and Eurya japonica were found to be high. In the naturally inhibited area of H. hamabo, a dominant value of Rubus parvifolius in the lower part of the herb layer was very high and many plants in Compositae, such as Artemisia princeps var. orientalis and Erigeron annuus, were also present. A dominant value of liana, such as Vitis thunbergii var. sinuata, Rosa multiflora, Clematis terniflora and Hedera rhombea, and Gramineae plants that rhizomes were well developed and aggressively propagated, such as Miscanthus sinensis var. purpurascens, Phragmites communis, Spodiopogon cotulifer and Oplismenus undulatifolius which were surveyed as high, too. These results imply that H. hamabo might be exterminated soon through a natural selection if the proper management of the naturally inhibited area of H. hamabo is not conducted continually.