• Journal of Forest and Environmental Science
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• 제32권3호
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• pp.237-252
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• 2016

Improved knowledge of the environmental factors affecting the natural regeneration of tree species in limestone forest is urgently required for species conservation. We examined the environmental factors and tree species characteristics that are important for colonization in diverse forest stands growing on a limestone hill in northern Thailand. Our analysis estimated the relative influence of forest structure and environmental factors on the regeneration traits of tree species. We established sixty-four $100-m^2$ plots in four forest stands on the limestone hill. We determined the species composition of canopy trees, regenerating seedlings, and saplings in relation to the physical environment. The relationships between environmental variables and tree species abundance were assessed by canonical correspondence analysis (CCA), and we used generalized linear mixed models to examine data on seedling/sapling abundances. The CCA ordination indicated that the abundance of tree species within the mixed deciduous forest was closely related to soil depth. The abundances of tree species growing within the sink-hole and hill-slope stands were positively related to the extent of rocky outcropping; light and soil moisture positively influenced the abundance of tree species in the hill-cliff stand. Physical factors had a greater effect on tree regeneration than did factors related to forest structure. Tree species, such as Ficus macleilandii, Dracaena cochinchinensis, and Phyllanthus mirabilis within the hill-cliff or sink-hole stand, colonized well on large rocky outcroppings that were well illuminated and had soft soils. These species regenerated well under conditions prevailing on the limestone hill. The colonization of several species in other stands was negatively influenced by environmental conditions at these sites. We found that natural regeneration of tree species on the limestone hill was difficult because of the prevailing combination of physical and biological factors. The influence of these factors was species dependent, and the magnitude of effects varied across forest stands.

• 농업생명과학연구
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• 제43권6호
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• pp.19-27
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• 2009

본 연구는 산불 피해지에서의 임분구조 및 입지환경인자를 분석함으로서 이에 따른 산화 피해정도를 모형화하고 산화피해지의 피해목 처리에 따른 구성종의 종다양도 및 그 식생회복 형태를 구명하고자 하였다. 입지환경인자에 의한 산화피해율간의 관계를 정준상관 분석 및 로지스틱 회귀분석한 결과, 해발고 200m, 100m, 사면경사가 30도 이상인 입지의 임분밀도가 높은 소나무단순단층림이 산화 발생 피해율이 높은 것으로 추정되었다. 산화지 피해목 처리방법에 따른 식생회복 과정을 분석한 결과 피해목 존치보다는 피해목을 제거하는 것이 식생회복에 효과적이라 사료되었다. 따라서 산불피해지에 대한 식생회복을 위한 적절한 시업적 조치는 입지, 자생 수종 등을 복합적으로 고려하여야 할 것으로 사료되었다.

• 한국환경복원기술학회지
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• 제2권1호
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• pp.38-47
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• 1999

The mixed rural city is adjusting to change by urbanization. The recent landcover change in mixed rural city is an important factor that changes structure and function of regional ecosystem. Landscape ecology is an integrated ecology widely available for environmental science such as nature conservation and sustainable land-use planning. As the concern about environmental quality rises, many studies are trying to create and conservate for biotop. The creation of biotop is related to the plan and management of the effective landuse because the important factor to change the structure and function of ecological area in the country. This study was carried out to establish the foundation of the landuse plan to analyze the change of landuse and to plan the scheme in creating biotop and landuse. We used the approach of ecological landscape and using landscape indices with RS(Remote Sensing) and GIS(Geographic Information System) technology, spatio-temporal variations of areas and distribution of forest patches were examined in the Sunghwan in Chonan from 1985 to 1996. A result of this study showed that the area of forest and paddy decreased by urban sprawl. The size of patch in the forest and agriculture had been smaller and irregular form, heterogeneity of size of forest and agriculture patches within sub-basin was increased, pattern of forest and agriculture patches decreased the corridor and network from 1985 to 1996.

• 한국환경과학회지
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• 제31권9호
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• pp.735-741
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• 2022

Global warming affects forests and their ecology. Diversity in the forest is a buffer that reduces the damage due to global warming. Mixed forests are ecologically more valuable as versatile habitats and are effective in preventing landslides. In Korea, most forests were created by simple afforestation with trees of evergreen species. Typically, evergreen trees are shallow-rooted, and deciduous trees are deep-rooted. Mixed forest tree roots grip the soil effectively, which reduces the occurrence of landslides. Therefore, improving the distribution of tree types is essential to reduce damage due to global warming. For this improvement, the investigation of tree types of the forest is needed. However, determining the tree type distribution of forests that are spread over wide areas is labor-intensive and time-consuming. This study suggests effective methods for determining the distribution of tree types in a forest that is spread across a relatively wide area. Using normalized difference vegetation index and RGB images from unmanned aerial vehicles, each evergreen and deciduous tree, and grassland area can be distinguished. The distinguished image determines the distribution of tree type. This method is effective compared to directly determining the tree type distribution in the forest by the use of manpower. The data from these methods could be applied to plan a mixed forest or to prepare for future damage due to global warming.

• International journal of advanced smart convergence
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• 제10권1호
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• pp.216-224
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• 2021

Aim of this research was to classify forest types at Wando in Jeonnam Province and develop warm temperate forest management system with application of Remote Sensing and GIS. Another emphasis was given to the analysis of satellite images to compare forest type changes over 10 year periods from 2009 to 2019. We have accomplished this study by using ArcGIS Pro and ENVI. For this research, Landsat satellite images were obtained by means of terrestrial, airborne and satellite imagery. Based on the field survey data, all land uses and forest types were divided into 5 forest classes; Evergreen broad-leaved forest, Evergreen Coniferous forest, Deciduous broad-leaved forest, Mixed fores, and others. Supervised classification was carried out with a random forest classifier based on manually collected training polygons in ROI. Accuracy assessment of the different forest types and land-cover classifications was calculated based on the reference polygons. Comparison of forest changes over 10 year periods resulted in different vegetation biomass volumes, producing the loss of deciduous forests in 2019 probably due to the expansion of residential areas and rapid deforestation.

• 한국환경복원기술학회지
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• 제27권3호
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• pp.1-18
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• 2024

The study aims to establish a direction for forest ecological restoration by classifying forest types and understanding the ecological characteristics of the Uljin forest area damaged by a large fire in 2022. Hierarchical cluster analysis and indicator species analysis were conducted on 78 survey plots located in the forest fire-affected area, and four forest cover types were derived: P. densiflora pure forests, P. densiflora dominant forests, mixed broad-leaved forests, and Q. variabilis dominant forests. As a result of visually comparing changes in forest types before and after forest fire damage, by classifying data according to whether or not upper dead trees are included, it was confirmed that pine forests, which have a high proportion of pine trees, spread widely due to forest fire damage. However, broad-leaved mixed forests and oyster oak dominant forests showed characteristics of maintaining concentration, indicating that pine forests were severely damaged. As a result of the important value analysis, during the process of natural recovery after a forest fire, the species that appear early in the lower layer are the sprouts of existing species such as Quercus mongolica Fisch. ex Ledeb., Quercus variabilis Blume, Fraxinus sieboldiana Blume, Rhododendron mucronulatum Turcz. The distribution of diameter at breast height by forest cover type showed that among areas with extreme forest fire damage, the proportion of dead trees was relatively high and structural changes were large in P. densiflora pure forests and P. densiflora dominant forests where pine trees had a high distribution ratio. However, if continuous monitoring is carried out in the future with reference to the results of this study and plant data is collected and analyzed from a mid- to long-term perspective, it is believed that it will be used as useful data to promote forest ecological restoration projects in forest fire-affected areas.

• Journal of Ecology and Environment
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• 제32권4호
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• pp.237-247
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• 2009

This study was conducted to determine the carbon (C) contents in different mixed stands of P. dens if/ora and deciduous oak species in Gwangneung, central Korea. Five mixed stands with different ratios of P. densiflora and deciduous oak species were chosen based on the basal area of all trees ${\geq}\;5cm$ DBH: pure P. densiflora (P100D0), 70% P. densiflora + 30% deciduous oak species (P70D30), 44% P. densiflora + 56% deciduous oak species (P50D50), 37% P. densiflora + 63% deciduous oak species (P40D60), and 10% P. densiflora + 90% deciduous oak species (P10D90). Total C contents in the overstory (aboveground and belowground) vegetation were higher in the mixed stands (P70D30, P50D50, P40D60) than in the pure stands (P100D0, P10D90). Moreover, except for P40D60, C contents of forest floor (litter and coarse woody debris) were larger in the mixed stands (P70D30, P50D50) than in the pure stands. However, total soil C contents up to 30cm depth were highest in the pure deciduous oak stand than in the pure P. densiflora stand and mixed stands. Total ecosystem C contents (Mg/ha) were 163.3 for P100D0, 152.3 for P70D30, 188.8 for P50D50, 160.2 for P40D60, and 150.4 for P10D90, respectively. These differences in total ecosystem C contents among the different mixed stands for P. densiflora and deciduous oak species within the study stands were attributed by the differences in vegetation development and forest management practices. Among the five study stands, the total ecosystem C contents were maximized in the 1:1 mixed ratio of P. densiflora and deciduous oak species (P50D50).

• 한국산림과학회지
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• 제90권5호
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• pp.632-642
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• 2001

강원도 양양군에서 소나무 단순림 5개소(個所)와 침엽수(針葉樹)와 관엽수(關葉樹)가 혼효(混淆)되어 있는 천연림(天然林) 내(內)의 지표동물, 특히 딱정벌레(Carabidae)를 대상으로 조사, 비교하였다. 소나무림 내에 서식하는 딱정벌레상(相)은 장소별 차이가 적게 나타났으며 토양동물군집(土讓動物群集)의 생물다양도(生物多樣度)도 낮았다. 딱정벌레 가운데 Synuchus 속(屬)의 종개체수(種個體數)는 솔잎혹파리(Thecodiplosis japonensis)의 피해솔(被害率)이 높은 장소 일 수록 증가(增加)하는 경향(傾向)이 나타났으며, 이 속(屬)에 속하는 종류(種類)는 솔잎혹파리를 섭식하는 주요한 보식자(補食者)로 파악되었다. 또한 침 활엽수가 혼효된 천연림(天然林)에 비하여 소나무림에는 상위(上位) 분류군(分類群)에 속하는 산림동물의 종수(種數) 및 딱정벌레과(科)의 속수(屬數) 종수(種數)가 모두 적었고, 특히 비상능력(飛翔能力)이 없는 대형 딱정벌레류의 대부분은 천연림(天然林)에서만 채집되었다. 따라서 해발고(海拔高)가 낮은 지역에 조성된 소나무림에서는 이전(以前)에 산림파괴(山林破壞)로 손실된 많은 종(種)이 아직도 회부(回復)되지 않은 것으로 파악되었다.

• 한국산림과학회지
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• 제96권2호
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• pp.227-234
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• 2007

The forest canopy gap has been well known as a substantial process of forest cyclic regeneration and important role in stand structure, dynamics, and biodiversity of the forest ecosystem. Based on 3,600 $5m{\times}5m$ square grids in a 9ha permanent experimental plot, the study was conducted to evaluate the regeneration pattern of woody species by developmental stage {seedlings (<1 m of height), saplingI (>1 m of height, <2 cm of DBH), and saplingII (2 cm$<200m^2$), $201-400m^2$, $400-600m^2$, $601-800m^2$, and $>800m^2$) in the mixed broadleaved-Korean pine forest. The results indicated that the regenerating trees of Populus ussuriensis occurred only in the canopy gap area, considered to be a typical gap-dependent species. The regeneration of Ulmus japonica, Ulmus laciniata, and Maackia amurensis could be generally satisfied with the gap size of $201-600m^2$, Betula costata and Prunus padus with gap size of $401-800m^2$, Picea koraiensis with gap size of $201-800m^2$, Fraxinus mandshurica and Syringa reticulata var. mandshurica with smaller than $800m^2$, respectively. Acer ukurunduense and Acer tegmentosum were likely to have no problem with the gap size to make gap regeneration. Acer mono and Tilia amurensis looked more capable of regenerating in the closed canopy disregarding the upper crown condition. The regeneration of Pinus koraiensis and Abies nephrolepis had no trouble under the canopy condition in less than $800m^2$of gap size. The density of regenerating shrubs was rather high, especially under the closed canopy, considered to be associated with great amount of regeneration production in such shade tolerant species as Lonicera maackii, Corylus mandshurica, Euonymus pauciflorus, and Philadelphus schrenkii under the closed canopy. Pearson correlation coefficient was computed to compare the similarity among non-gap area and five gap size classes by developmental stages for trees and shrubs. The similarity coefficients among closed canopy and the gap size classes were mostly significantly correlated to each other with a few exceptions.

• 펄프종이기술
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• 제43권5호
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• pp.60-67
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• 2011

Hemicelluloses pre-extracted from Korean mixed wood chip were investigated as a wet-end additive. Hemicelluloses dissolved in hot water and alkali solution were isolated by ethyl alcohol precipitation from pre-extractives. They showed molecular weight of 9,000 ~ 27,000 g/mol as revealed by size exclusion chromatography. The reduction of molecular weight through hot water extraction was caused by autohydrolysis. Chemical composition of the hemicelluloses were analyzed with high-performance liquid chromatography and UV-Vis spectroscopy. As the surface charge of isolated hemicelluloses were negative, the adsorption of hemicelluloses onto softwood unbleached kraft pulp fiber was promoted by poly-DADMAC. The physical properties of handsheets increased as the molecular weight of hemicellulose increased. On the other hands, the optical property decreased with hemicellulose adsorption.