• Journal of Forest and Environmental Science
• /
• v.33 no.2
• /
• pp.136-146
• /
• 2017

We selected 6 plots ($100m^2$) located 2.2-3.8 km from Minamidake Crater on the north flank of Sakurajima Volcano. We conducted a field study to investigate the effects of volcanic activity on vegetation succession and surface erosion rate. The results showed that trees growing in plots further from the crater had a greater diameter at breast height (DBH), total height, and age. In addition, these plots had a greater number of woody plants and species, as well as a greater total cross-sectional area at breast height. The Fisher-Williams index of diversity (${\alpha}$) and the proportion of evergreen broad-leaved trees were higher in plots located further from the crater. Vegetation succession in these plots was not at the level of a climax forest. From 1972 to 2015, the timing for active volcano, the depth of volcanic ash layer, the dry density, and the pH of ground surface were lower for plots located further from the crater. Furthermore, the average annual sheet erosion from 1972 to 2015 was also lower for plots located further away from the crater. Overall, plots further away from the crater have a better environment for vegetation growth and a lower dry density of the volcanic ash surface layer. It is thought that lower dry density results in increased soil permeability, which impedes surface flow. In order to prevent debris-flow disasters, caused by mud and rock flow resulting from impaired soil penetrability, it is essential to promote soil development and restore penetrability by artificial vegetation restoration.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.21 no.4
• /
• pp.277-285
• /
• 2019

This study was conducted to understand the growth characteristics of Picea jezoensis that was one of representative subalpine species in Korea, in the light of the effects of wind and micro-topography in its habitats on Mt. Deogyu, Korea. The prevailing wind directions were southwest and west at the study sites. We randomly selected P. jezoensis (height ≥ 1.5 m) on windward, intermediate, and leeward slopes and measured diameter at breast height (DBH), height, crown length by 8 directions in upper, middle and lower sectors of the crown. We examined the micro-topography of P. jezoensis stood on and classified it into 3 types: type 1 was mounded and fully exposed to surrounding environments without neighboring trees; type 2 was somewhat wind-protected by surrounding rocks, but no neighboring vegetation; type 3 was on gentle slope or flat where P. jezoensis grew with neighboring trees or shrubs. The ratios of height to DBH, and estimated crown growth to actual crown growth (hereafter crown growth ratio) were compared among the three types of micro-topography on windward, intermediate and leeward sites. The height growth per DBH and crown growth ratio in the upper and middle crowns were the smallest on the windward site, and the highest on the leeward site (p < 0.01). The crown growth ratio on type 1 on the windward site was only 46% of that on type 3 on the leeward site. Although on the same windward slope, trees on type 1 had more deformed crown shapes than that on Type 3, showing asymmetric crown cross-sectional areas. Wind and micro-topography played critical roles on the crown growth of P. jezoensis.

• Korean Journal of Soil Science and Fertilizer
• /
• v.42 no.5
• /
• pp.323-329
• /
• 2009

This study was conducted to analyze growth responses of fast growing tree species(8 clones of hybrid poplars, Salix alba, Metasequoia glyptostroboides, Liriodendron tulipifera, Acer okamotoanum, and Quercus palustris), the chemical characteristics of soil and $NO_3-N$ concentration of groundwater in a plantation applied with liquid pig manure. Concentrations of nitrogen and phosphorous in the soil treated with liquid pig manure were higher than that of the soil treated without liquid pig manure. With the exception of S. alba, DBH(Diameter at Breast Height) growth of all the fast growing tree species treated with liquid pig manure was higher than that of the species treated without liquid pig manure. In liquid pig manure treatment group, P. euramericana 'Eco28' clone showed the best performance in height and DBH growth. Concentration of nitrogen in the leaf with liquid pig manure was higher than that of the leaf treated without liquid pig manure. Based on the $NO_3-N$ concentration of groundwater analyzed during the experimental period, there was no evidence that groundwater was polluted by the liquid pig manure applied at the plantation.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.17 no.1
• /
• pp.58-68
• /
• 2015

This study compares the wind stability of Larix kaempferi (Lamb.) Carr., Pinus koraiensis Sie. & Zucc. and Abies holophylla Maxim. to understand and inform wind risk management of these plantation trees at Daegwallyeong, Korea. Temporary square plots of $20m{\times}20m$ ($400m^2$) were laid out, and DBH (Diameter at Breast Height) and height for trees greater than 10 cm in DBH were measured by species. A total of 15 plots with 5 plots each in L. kaempferi, P. koraiensis and A. holophylla stands were sampled at random. Among the species, A. holophylla and P. koraiensis have comparatively lower h/d (Height/DBH) ratios than L. kaempferi. These results indicate that the former two species are more wind firm than the latter species. About 9% of the L. kaempferi trees have higher h/d ratios than the critical threshold limit 80. These trees are vulnerable to wind damage and should be removed in the next thinning regime. The analysis of variance detected a significant difference (p < 0.05) in the h/d ratios and Gini coefficient indicating species differences and DBH size variation, respectively. Gini coefficient was 16.4% in A. holophylla, 15.9% in P. koraiensis and 14% in L. kaempferi stands indicating limited DBH size variation. Lower h/d ratios are attributed to thinning in these stands and tree morphological differences. To increase wind firmness, low thinning should concentrate to remove trees with the h/d ratio above 80 coinciding at the time of stand distinction phase. Forest managers and practitioners should measure and maintain h/d ratios of trees below the critical threshold limit of 80 through stand density management. Variable density thinning approach should be tested to increase tree DBH sizes of the even-aged stands.

• Journal of Korean Society of Forest Science
• /
• v.112 no.1
• /
• pp.83-92
• /
• 2023

This study was established to investigate the site environment of mixed forests in Korea and to estimate the growth and yield of stands using national forest resources inventory data. The growth of mixed forests was derived by applying the Chapman-Richards model with diameter at breast height (DBH), height, and cross-sectional area at breast height (BA), and the yield of mixed forests was derived by applying stepwise regression analysis with factors such as cross-sectional area at breast height, site index (SI), age, and standing tree density per ha. Mixed forests were found to be growing in various locations. By climate zone, more than half of them were distributed in the temperate central region. By altitude, about 62% were distributed at 101-400 m. The fitness indexes (FI) for the growth model of mixed forests, which is the independent variable of stand age, were 0.32 for the DBH estimation, 0.22 for the height estimation, and 0.18 for the basal area at breast height estimation, which were somewhat low. However, considering the graph and residual between the estimated and measured values of the estimation equation, the use of this estimation model is not expected to cause any particular problems. The yield prediction model of mixed forests was derived as follows: Stand volume =-162.6859+6.3434 ∙ BA+9.9214 ∙ SI+0.7271 ∙ Age, which is a step- by-step input of basal area at breast height (BA), site index (SI), and age among several growth factors, and the determination coefficient (R²) of the equation was about 96%. Using our optimal growth and yield prediction model, a makeshift stand yield table was created. This table of mixed forests was also used to derive the rotation of the highest production in volume.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.16 no.5
• /
• pp.83-92
• /
• 2013

The present study documented the characteristics of habitats and nests of Goshawk [Northern goshawk] Accipiter gentilis breeding in Gongju-si, Chungcheongnam-do and Haepyung, Kyungsangbuk-do, Eumsung-gun, Chungju-si, Chungcheongbuk-do from April 2007 to August 2011. Breeding habitat includes of mixes and deciduous trees and ravine forest, ranging from small to large areas and it used make a new nest and fix up the old nest at Goshawk. Goshawk make nests on Japanese larch Larix leptolepis, Japanese red pine Pinus densiflora and Pitch pine Pinus rigidae of $15.8{\pm}2.36m$ (range=7.4~18.7m) in height and $34.6{\pm}7.38cm$ (range=20.8~47.4cm) in diameter-at-breast height (DBH). It has $135.8{\pm}3.37cm$ in outer diameter of nest, $26.2{\pm}2.39cm$ in inner diameter, $7.1{\pm}1.41cm$ of depth, and $3.1{\pm}0.40Kg$ of weight. Breeding habitat (n=13) has 5~7 nests. It has 7 (53.8%) nest in fix up the old nest and 4 (30.8%)nests in make a new nest.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.11 no.2
• /
• pp.55-65
• /
• 2008

This study was surveyed to analyze vegetation structure of mountainous wetlands in Chung-ju city and around area from September to November, 2006. 6 sites of total 15 potential mountainous wetlands were discriminated throughout field survey. By classification system of mountainous wetlands presented in manual of forest wetlands research, types of wetlands were classified into slant and a flat. Many sites were covered with land plants as Pueraria thunbergiana and so on. To understand vegetation structure of mountainous wetlands, Height, DBH (diameter at breast height), DI (Dominance Index), Sociability and Constancy were surveyed and Based on this result, a projection chart was drawn. As results, Salix koreensis in tree layer and Persicaria thunbergii and Impatiens textori in herb layer were surveyed as broadly distributed species. This study is mainly focused on vegetation condition of mountainous wetlands. But, it will be needed studying on classification system of mountainous wetland type and functional assessment for conservation or management of wetlands.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.13 no.1
• /
• pp.1-13
• /
• 2010

This study was accomplished to identify and analyze vegetation structure of Mountainous Wetlands in Dan-yang and around area, and surveyed from September to November, 2006. 6 sites of total 16 potential Mountainous Wetlands by GIS based wetland forecasting system (Korea National Arboretum, 2006) were identified as wetlands throughout field survey by the indicators such as hydrology, soil and vegetation. By classification system of Korea National Arboretum (2006), types of wetlands were classified into 3 slope-types and 3 flat-types. To understand vegetation structure of wetlands, height, DBH (diameter at breast height), DI (Dominance Index), sociability and constancy were surveyed and the projection diagram and charts ware drawn. As results, Salix koreensis in woody plant layer and Persicaria thunbergiiin and Juncus effusus var. decipiens in herb layer were surveyed as broadly distributed species. The wetlands of Dan-yang around area were similar to those of Chung-ju around area, but the species of plants and hydrology conditions were different. This study is mainly focused on vegetation condition of Mountainous Wetlands. But, further studies on functional assessment for management and restoration of wetlands were necessary.

• Journal of Ecology and Environment
• /
• v.33 no.1
• /
• pp.67-77
• /
• 2010

Stand structure and spatial associations of the dominant tree species in Quercus mongolica stands were investigated to understand interspecific relationships and the persistent dominance of Q. mongolica. We examined the species composition, DBH (diameter at breast height) distribution, and spatial distribution of trees (${\geq}\;2.5\;cm$ DBH) in two permanent $100\;m\;{\times}\;100\;m$ plots in Q. mongolica-dominant stands on the western part of Mt. Jiri. Ripley's K-function was used to characterize the spatial patterns and associations of dominant tree species. Q. mongolica showed a continuous and reverse-J shaped DBH distribution with clumped spatial distribution in both study sites. Q. mongolica and Abies koreana exhibited a negative association implying potential interspecific competition. The positive spatial association between Q. mongolica and Alnus hirsuta var. sibirica and Fraxinus sieboldiana were affected by site characteristics: limited habitat conditions with a large proportion of rock surface. Our results suggest that interactions among species were complex and ranged from positive to negative. Differences in stand and site characteristics and regeneration mechanisms among the species play an important role in regulating their spatial distribution patterns, while competition between individuals also contributes to spatial patterning of these communities. The high density and the early developmental stage of spatial distribution and structural characteristics of Q. mongolica and the relatively low importance values of other species in the stands imply that Q. mongolica will remain dominant in the study sites in the near future.

• Korean Journal of Plant Resources
• /
• v.36 no.1
• /
• pp.91-99
• /
• 2023

Plus tree selection is the essential first step in a tree improvement program. This study was carried out to select plus trees of black locust (Robinia pseudoacacia L.) for tree improvement in Korea. The candidate plus trees of black locust were selected from twenty-one places in the four provinces (Gangwon, Gyeonggi, Chungcheong and Gyeongsang) following comparison selection. The trees were examined for qualitative and quantitative traits of economic interest like tree height (H), diameter at breast height (DBH), clear bole height (CBH), stem straightness (SS), crown size (CS) and disease resistance. The 64 selected trees showed higher quality in growth characteristics than control trees. Average of height, DBH, CBH, SS and CS were 20.5 m, 31.1 cm, 10.1 m, 1.2 and 5.2 m respectively. In particular, it was shown that the growth characteristics were higher in Chungcheong population. The superiority percentage of selected candidate plus trees of black locust over their respective check trees ranged from 7.3% to 18.9% in height, 20.0% to 40.6% in DBH, 32.8% to 73.5% in CBH, 42.9% to 55.2% in SS and -11.1% to 9.4% in CS, respectively. The selected black locust will be useful in future tree breeding programs based on their clonal and progeny performance.