• Proceedings of the Korea Water Resources Association Conference
• /
• 2009.05a
• /
• pp.1764-1768
• /
• 2009

현재 국내에서 치수경제성분석을 위한 홍수피해산정법으로는 하천설계기준에 제시되어 있는 다차원홍수 피해산정법(MD-FDA: Multi-Dimensional Flood Damage Analysis)이 광범위하게 사용되고 있다. 그러나 2004년 처음으로 지침이 나온 이후 각종 자산조사 원단위에 대한 갱신이 이루어지지 않아 현재 실정에 맞는 자산조사가 불가능하며, 일부 산정방식에서는 문제점도 지적되고 있다. 따라서 본 연구에서는 주거자산, 농업자산, 산업자산으로 나누어진 자산 항목과 인명피해액 산정을 위한 인명손실에 대한 각각의 원단위를 갱신하여 현재 경제상황에 맞는 적용이 이루어질 수 있게 하였다. 또한 과거 문제점이 지적되던 산정방식에 대해서 일부는 기술 방식을 고쳐 이해를 돕고, 일부는 새로운 방법론을 제시하였다. 그럼에도 불구하고 갱신된 원단위가 현재의 사회경제적 상황을 완벽히 반영한다고 판단되지는 않는다. 이는 통계자료의 양적 질적 부족으로 인해 기인된 것이다. 그러나 2004년 다차원홍수피해산정법이 처음 제시된 이후로 원단위의 갱신이 이루어지지 않았던 데 비해 통계자료의 형식적 내용적 변화상을 반영할 수 있게 하였다는 점에 있어서 연구의 의미가 있다. 본 연구의 결과 변경된 자산조사 방식과 각종 원단위는 치수계획 실무에서 홍수피해산정시 많은 참고가 될 것이다.

• Journal of Korean Society of Forest Science
• /
• v.94 no.1 s.158
• /
• pp.6-10
• /
• 2005

This study was conducted to understand the dynamics of naturally regenerated seedlings and saplings in 28years after selective cutting at natural Korean pine-broadleaved forests in Mt. Changbai. The number of naturally regenerated tree species was 16 species in 28 years after selective cutting. The appearance rate of naturally regenerated tree species was 56 percentage and the early-successional tree species of Acer ukurunduense, Acer mono, Acer pseudosieboldianum, Prunus padus var. pubescens, and Maackia amurensis were found in the first 10 years after selective cutting. The seedlings and saplings of shade-tolerant tree species of Pinus koraiensis, Acer mandshuricum, Ulmus laciniata were appeared and the appearance rate was higher than 75% after 15 years while it showed little changes from 19 years after selective cutting. The distribution density of seedlings and saplings of regenerated tree species in selective cutting area was 5,500~6,100 trees per hectare in the first 10 years, and it increased gradually along with the restoration of disturbed area and it could reach 7,500 trees per hectare after 15 years.

• Journal of Korean Society of Forest Science
• /
• v.109 no.4
• /
• pp.400-412
• /
• 2020

We analyzed the growth characteristics of naturally regenerated seedings of Larix kaempferi in order to propose a field-applicable regeneration method. Experimental sites were established at Gapyeong in Gyeonggi-do and at Bonghwa in Gyeongsangbuk-do. We analyzed seed inflow features, occurrence, and growth characteristics of natural seedlings for three years. The reserved seed-tree site producedthe greatest number of inflow seeds and followed by seed-tree site and clear-cut site. In addition, the reserved seed-tree method was found to be more efficient than other methods in evenly scattering seeds. The rate of seedling occurrence at treatment sites (e.g., harvesting and scratching) was 2.4%, which is 8.0 times higher than the seedling occurrence (0.3%) at the non-treatment sites. There were approximately 470,000 seedlings per hectare at the treatment sites in June of the first year after regeneration and approximately 78,000 seedlings per hectare in October of the third year. The average diameter of the root collar of the seedlings in the third year was 6.5 mm, and the average height of the seedlings was 50.4 cm. These results indicate that it is possible to create a secondary forest of L. kaempferi by natural regeneration if harvesting and scraping are implemented during seed fructification. Considering the rapid growth of L. kaempferi shown in this study, the proposed method would be an efficient reforestation technique.

• Korean Journal of Environment and Ecology
• /
• v.17 no.2
• /
• pp.144-152
• /
• 2003

The purpose of this study was to investigate the effects of lime fertilization and light intensity on beech regeneration strategy in a mature beech forest(ca. 150 years old) gaps, which was located in the soiling areas Germany, where the soil is an acid brown earth. For the experiment canopy gaps of 30m diameter were cut, and one canopy gap remained as untreated while the other was limed(3t dolomite h $a^{-1}$). Soil chemistry, soil water potential, light intensity(PAR), ground vegetation, beech seedlings and mycorrhiza were investigated along transect from the stands into gaps to the north. The results of this study are followings: 1) In the limed gap, soil chemistry was greatly improved and a vigorous herb layer developed as compared to the unlimed gap. 2) Development and growth of the beech seedlings in the unlimed gap were generally deficient. Specially, developments of lateral roots were very lack. 3) Through the lime fertilization, the minerals contents of beech leaves such as calcium(Ca) and magnesium(Mg) were increased, while manganese(Mn) was decreased. There was antagonism between potassium(K) and calcium(Ca) or magnesium(Mg). 4) The relative mycorrhiza frequency(RM) in beech seedlings of the southern edge was very higher than that of the middle part, and through the lime fertilization extension of the species Laccaria amethystina appeared clearly. The results of this study showed that lime fertilize in forest, where the soil is acid, will be necessary..

• Journal of Korean Society of Forest Science
• /
• v.108 no.2
• /
• pp.189-199
• /
• 2019

The forest management paradigm has recently shifted from focusing on commercial production to focusing on ecosystem management. Accordingly, a natural seedling regeneration method that has a naturally high affinity has attracted much attention in recent years. The aim of this study was to determine the relationship among various environmental factors, lower stratum vegetation, and seedling regeneration in Pinus densiflora forests. The survey site comprised 50 sectors divided using the line transect method, and the survey data were divided into those from wet habitat (19 sites) and dry habitat (31 sites), depending on the soil humidity, and were analyzed separately to show the close relationship between soil humidity and natural seedling regeneration. As a result, the dry habitat exhibited high seedling density (157,419 trees/ha), with the main species being Quercus serrata, Zanthoxylum piperitum, Smilax china, and Pueraria lobata, while wet habitat exhibited low seedling density (57,895 trees/ha), with the main species being Stephanandra incisa, Castanea crenata, Lespedeza maximowiczii, Lysimachia barystachys, Aralia elata, and Styrax japonicus. The height and root-collar diameter under wet conditions exhibited faster growth than those under dry conditions. Height growth by the root-collar diameter in dry habitat increased faster than that in wet habitat. It was also confirmed that seedling regeneration in wet habitat exhibited a rapid growth pattern 5 years after germination. These results suggest that the seedlings begin to grow more rapidly after a period of suppression by competition with surrounding plants. Considering an ecosystem or ecological management approach, specific practices, such as bush control and vine clearing in wet habitats, should be more intensively conducted, especially at the beginning of the management operations.

• Journal of Korean Society of Forest Science
• /
• v.107 no.1
• /
• pp.25-34
• /
• 2018

This study was performed to discover the comparison of the understory species composition and the growth velocity of the regeneration seedlings in Pinus densiflora forests being managed by the seed-tree method from 2008 year. The investigation site located in Bonghwa, Gyeongsangbuk-do province was established by eighteen quadrats such as six control ones, six slope ones and 6 concave ones, in which we carried out the vegetation survey and measured annual height growth of each seedlings. As a result of vegetation analysis, the understory vegetation of the seed-tree forest area was mainly composed of shrub plants such as Lespedeza bicolor, Zanthoxylum schinifolium, Securinega suffruticosa, Lespedeza maximowiczii and Stephanandra incisa, herb plants such as Miscanthus sinensis var. purpurascens, Carex humilis var. nana, Spodiopogon sibiricus and Artemisia keiskeana, and vine plants such as Pueraria lobata, Smilax sieboldii, Dioscorea batatas, Actinidia arguta, Vitis amurensis and Rubus crataegifolius. Especially, the vine plants were relatively more imported to the concave site than the control site and the slope site. As a result of measurement of growth velocity, the seedlings of the Pinus densiflora appeared to be 3,175 trees/ha for the non-suppressed trees and 7,842 trees/ha for the suppressed trees. In cases of the concave site, individuals of seedlings were much lower than those on the slope site, probably due to the competition effects of vine plants. Consideringly, silvicultural practices for clearing the vine plants should be inevitably accompanied. Also, the growth velocity of the suppressed and non-suppressed trees has been constantly increasing, those of the non-suppressed trees much higher than the suppressed trees. This represents that the seedlings grow rapidly after the suppressed period with competition to the surrounding plants. Therefore, specific practices such as blush control and vine clear should be carried out at the beginning stage of regeneration in the seed-tree stand.

• Journal of Korean Society of Forest Science
• /
• v.85 no.3
• /
• pp.524-531
• /
• 1996

The objective of this study was to determine the important factors affecting the early natural regeneration of Pinus densiflora S. et Z. Seed germination, survival and height growth of the pine seedlings were examined at four experimental plots of P. densiflora forests including forest roadside. Plots I and III were thinned in 1992, plot II was treated with hexazinone in 1993 after seed tree method was applied in 1982 and 1989. Seedlings emerged after thinning and the rate of their emergence depended on forest floor conditions. Seedling survival was related with light conditions, herbaceous vegetation, and degrees of rainfall. More seedlings emerged in forest hauling roads than within the forest because soil scarification due to logging provided better conditions for seed germination and seedling growth. Seed supply was enough, but germination rate was very low in the forest compared with that in the greenhouse because micro-environments such as organic layer and herbaceous plant acted as limiting factors. Weed control was needed for 4 to 5 years until seedlings grew upto about 50cm in height which was similar to that of herbaceous plants. But 10-40% coverage of herbaceous vegetation was needed to protect small seedlings from heavy rain. Forest works such as thinning and logging, over 40% of light were important factors to help the pine regeneration. However, over 70% coverage of herbaceous vegetation, and heavy rain inhibited rather survival and growth of pine seedlings.

• Journal of Korean Society of Forest Science
• /
• v.112 no.3
• /
• pp.280-289
• /
• 2023

Diverse native tree species are distributed in Korean forests; however, information on their regeneration strategies is limited. This study analyzed seed rain from 2011 to 2013, seedling emergence, seedling survival, lifespan distribution, and the relationship between seedling mortality and herbaceous vegetation for 3 years, from 2012 to 2014, to understand the natural regeneration and early survival characteristics of Fraxinus rhynchophylla Hance in natural broad-leaved forests. Seed rain and emerged seedling density significantly differed among the years (p < .05). An increase in seed rain was followed by an increase in seedling emergence in the following year. Seed rain in 2013 and seedling emergence in 2014 showed a significant correlation (p < .05), confirming the trait of F. rhynchophylla seeds that germinate in the following year after seed production. Seedlings emerged in late spring and early summer. Of the seedlings, 78% emerged in the early summer of 2014. Most seedlings died immediately after emergence. Of the seedlings that emerged in August 2012, 56% died within 2 months, and 38% of those that emerged in July 2014 died within 1 month. Shade and competition against ground vegetation chiefly affected the seedling survival of F. rhynchophylla. Fraxinus rhynchophylla showed mast seeding, with a large number of seed production in a particular year. A surge of seedling emergence followed in the early summer of the next year. However, most seedlings died in the same year of emergence. Fraxinus rhynchophylla has a high seedling mortality, but mast seeding and the resulting high seedling emergence produce a few survived seedlings, enabling the continuation of the F. rhynchophylla population. Efforts and research on the natural regeneration of native tree species are required to effectively manage natural forests in Korea.

• Journal of Korean Society of Forest Science
• /
• v.96 no.1
• /
• pp.107-114
• /
• 2007

Establishments of the seedlings inside the natural forest from adjacent artificial forests would be an important factor in forest stand dynamics. This study was conducted to see the invasion of Korean pine (Pinus koraiensis) seedlings which is not native in this region, into the natural deciduous broad-leaved forest in Gwangneung, Korea. There is no mother tree at the I ha study site while the number of naturally regenerated P. koraiensis seedlings was 345 trees and 56% of them were clumped with more than two seedlings at each point. Applying the image segmentation method to IKONOS satellite image of January, 2003, the distance from the center of 1 ha study site to the nearest mother tree and plantation of Korean pine were 200 m and 270 m, respectively. The average height and root-collar diameter of the seedlings were 34 em and 7 mm, respectively and the age of 207 seedlings (60%) were below 5 years old. Most abundant range of soil moisture gradient and LAl (leaf area index) were from 16 to 20% and those of LAI were from 3.1 to 3.5. To understand the dynamics and seed dispersal pattern of Korean pine in the Gwangneung natural deciduous broad-leaved forests, additional studies not only long-term monitoring of growth and mortality of naturally regenerated Korean pine seedlings but also application of stable isotope analysis and molecular genetic techniques was recommended.

• Journal of Forest and Environmental Science
• /
• v.17 no.1
• /
• pp.1-17
• /
• 2001

Forming a part of "Cooperative Practical Study for the Modernization of the Management of National Forest", this study was conducted to provide overall ecological information for the natural regeneration of major tree species on the basis of community structural attributes in the deciduous forest ecosystem. Followings are summarized characteristics of the natural regeneration for the selected tree species. Betula costata : Although large number of seeds are dispersed by wind, they require mineral soils to germinate. Thick litter layer could be an obstacle to germinate. After germination, the seedling requires large amount of light for successful establishment. Acer mono : Characterized by high shade tolerance and weak drought resistance, the seedling should be overcasted with more than 50% of canopy coverage. High stand density should be maintained to produce good quality of timber. The potential of coppice may be high. Ulmus laciniata : Since this species needs high rate of troll moisture and light, around 60% of canopy coverage should be maintained to retain moisture and incoming light. The competition with other vegetation should be removed for the favor of successful seedling establishment. Fraxinus mandshurica : This species requires moist mineral soils to germinate. After germination, the seedling needs large amount of light and moisture for successful establishment. Site preparation should be applied to reduce competition with weedy vegetation. Fraxinus rhynchophylla : Interval of large seed crops may be highly varied. Thick litter layer could be an obstacle to germinate. Site preparation should be applied to reduce competition with weedy vegetation so as to achieve successful seedling establishment. Quercus mongolica : Including the difficulty of seed supply by the consumption, thick litter layer and mountain bamboo cover could be the obstacle to germinate. More than 50% of relative light intensity is necessary to achieve successful seedling establishment. Kalopanax pictus : Thick litter layer could be an obstacle to germinate. The seedling needs large amount of light and moisture for successful establishment. Abies holophylla : In spite of high shade tolerance, the growth rate in sapling stage may be extremely slow. Cornus controversa : Seeds (drups) are consumed and dispersed by animals, tending to be not sufficient in seed supply. This species requires large amount of light for successful germination and seedling establishment. Tilia amurensis : The difficulty of seed supply might be expected with low seed purity and double dormancy. Since thick litter layer could be an obstacle to germinate, the species requires moist mineral soils for successful germination. The potential of coppice may be extremely high.