• Title/Summary/Keyword: forest environmental factors

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Evaluation of Watershed Stability by the Forest Environmental and Stream Morphological Factors (산림환경 및 하천형태인자에 의한 유역안정성 평가)

  • Jung, Won-Ok;Ma, Ho-Seop
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.4 no.4
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    • pp.1-11
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    • 2001
  • This study was carried out to analyze the characteristics of forest environmental and stream morphological factors by using the quantification theory(I) for evaluation of the watershed stability. Present annual mean sediment yield of erosion control dams were investigated in 167 sites of erosion control dam constructed during 1986 to 1999 in Gyeongbuk. The results obtained from this study were summarized as follows; According to the coefficients of partial correlation, each factor affecting to sediment was shown in order of gravel contents, number of first streams order, number of total streams, length of total streams, forest type, length of main stream, parent rock, stand age, soil texture, stream order, slope gradient, soil depth and aspect. Descriptions of class I were as follow; Igneous rock of parent rock, hardwood stands of forest type, less than 20 year of stand age, less than 30cm of soil depth, sandy clay loam of soil texture, more than 41% of gravel contents, south~east of aspect, 2,501~3,500m of length of main stream, 21~25 of number of total streams, 5,501~10,000m of length of total streams, 3 or more than 4 of stream order, more than 16 of number of first stream orders and more than $31^{\circ}$ of slope gradient. Descriptions of class II were as follow; Metamorphic rock of parent rock, coniferous stands of forest type, more than 25 year of stand age, 31~40cm of soil depth, silt loam of soil texture, 11~20% of gravel contents, north~west of aspect, 2,501~3,500m of length of main stream, 16~20 of number of total streams, 3,501~5,500m of length of total streams, 3 of stream order, 11~15 of number of first stream orders and more than $31^{\circ}$ of slope gradient. Descriptions of class III were as follow; Sedimentary rock of parent rock, mixed stands of forest type, more than 25 year of stand age, more than 51cm of soil depth, silty clay loam of soil texture, less than 10% of gravel contents, south~west of aspect, less than 500m of length of main stream, less than 5 of number of total streams, less than 1,000m of length of total streams, less than 1 of stream order, less than 2 of number of first stream orders and less than $25^{\circ}$ of slope gradient. The prediction method of suitable site for erosion control dam divided into class I, II, and III for the convenience of use. The score of class I evaluated as a very unstable area was more than 8.4494. A score of class II was 8.4493 to 6.0452, it was evaluated as a moderate stable area, and class III was less than 6.0541, it was evaluated as a very stable area.

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Mapping Distribution of Dipterocarpus in East Kalimantan, Indonesia

  • Aoyagi, Kota;Tsuyuki, Satoshi;Phua, Mui-How;Teo, Stephen
    • Journal of Forest and Environmental Science
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    • v.28 no.3
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    • pp.179-184
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    • 2012
  • Dipterocarps (Dipterocarpaceae) is a dominant tree family of tropical rainforest in Southeast Asia. Dipterocarps have been exploited for its timber and disappearing fast in East Kalimantan. In this study, we predicted the distribution of dipterocarpus, one of the main dipterocarps genera, by evaluating its habitat suitability using logistic regression analysis with specimen collection points and environmental factors from GIS data. Current distribution of dipterocarpus was generated by combining the habitat suitability classes with an updated forest cover map. Rainfall, soil type, followed by elevation was the main factors that influence the distribution of dipterocarpus in East Kalimantan. Dipterocarpus can be found in a quarter of the current forest cover, which is highly suitable as habitat of Dipterocarpus.

An Application of Ordinations to Kwangnung Forest (광릉 삼림 군집에 대한 Ordination 방법의 적용)

  • 강윤순
    • Journal of Plant Biology
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    • v.25 no.2
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    • pp.83-99
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    • 1982
  • In this study, thirty-two stands in Kwangnung forest located in the central part of Korea were preferentially selected. In each stand, all stems for trees and shrubs were recorded by species and their girths were measured down to 5cm. In addition, several enviromental factors such as field soil pH, field soil moisture, soil compressibility, depth of soil, thickness of litter layer, elevation and basal area were measured. Three soil cores were sampled and various physical and chemcial properties was determined. The vegetational data were subjected to three kinds of multivariate ordination(PO, PCA, RA). The results suggested that Kwangnung forest was consisted of three forest types: coniferous, mixed and broad leaved forest communities. The relation between the stand scores of ordination and several environmental factors were investigated in terms of correlation analysis in order to examine the relationships between the vegetation and certain environmental factors. As a result of this analysis, the amount of sand content in A1 horizon decreased frm the coniferous to broad leaved forest, while maximum field capacity, pore space, exchangeable cations, loss on ignition, soil pH nad the amount of total nitrogen had a tendancy to increase significantly. However, easily soluble phosphorus appeared to have little to do with the forest types. The result of species ordination of centered-standardized PCA suggested that the major successional pathway in Kwangnung forest was; Pinus densifloralongrightarrowQuercus mongolica, Q. serrata, Q. alienalongrightarrowCarpinus laxifloralongrightarrowC. erosa in sequence. This trend is in good agreement with the past studies. In three kinds of ordination (centered PCA, centered-standardized PCA and RA) based on nineteen species and twenty-five stands, the total variances accounted for the first three axes were 77%, 46% and 63% respectively. The estimated beta diversity in Kwangnung forest assumed as a coenocline, was 1.5~1.8 HC. Increasing the effect of the sampling errors on ordination perfermance, this low heterogeneity seems to cause the poor concentration of the total variance. The results from the four kinds of ordination were in good agreement with each other, especially between PO, centered-standardized PCA and RA appeared robust. It seems to be worthy of applying multivariate method for analyzing other forest communities in Korea.

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Analysis of the Individual Tree Growth for Urban Forest using Multi-temporal airborne LiDAR dataset (다중시기 항공 LiDAR를 활용한 도시림 개체목 수고생장분석)

  • Kim, Seoung-Yeal;Kim, Whee-Moon;Song, Won-Kyong;Choi, Young-Eun;Choi, Jae-Yong;Moon, Guen-Soo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.22 no.5
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    • pp.1-12
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    • 2019
  • It is important to measure the height of trees as an essential element for assessing the forest health in urban areas. Therefore, an automated method that can measure the height of individual tree as a three-dimensional forest information is needed in an extensive and dense forest. Since airborne LiDAR dataset is easy to analyze the tree height(z-coordinate) of forests, studies on individual tree height measurement could be performed as an assessment forest health. Especially in urban forests, that adversely affected by habitat fragmentation and isolation. So this study was analyzed to measure the height of individual trees for assessing the urban forests health, Furthermore to identify environmental factors that affect forest growth. The survey was conducted in the Mt. Bongseo located in Seobuk-gu. Cheonan-si(Middle Chungcheong Province). We segment the individual trees on coniferous by automatic method using the airborne LiDAR dataset of the two periods (year of 2016 and 2017) and to find out individual tree growth. Segmentation of individual trees was performed by using the watershed algorithm and the local maximum, and the tree growth was determined by the difference of the tree height according to the two periods. After we clarify the relationship between the environmental factors affecting the tree growth. The tree growth of Mt. Bongseo was about 20cm for a year, and it was analyzed to be lower than 23.9cm/year of the growth of the dominant species, Pinus rigida. This may have an adverse effect on the growth of isolated urban forests. It also determined different trees growth according to age, diameter and density class in the stock map, effective soil depth and drainage grade in the soil map. There was a statistically significant positive correlation between the distance to the road and the solar radiation as an environmental factor affecting the tree growth. Since there is less correlation, it is necessary to determine other influencing factors affecting tree growth in urban forests besides anthropogenic influences. This study is the first data for the analysis of segmentation and the growth of the individual tree, and it can be used as a scientific data of the urban forest health assessment and management.

Analysis of Forest Image according to Main Tree Species (숲의 주요 수종에 따른 이미지의 규명)

  • Kim, Jin-Sook;Shin, Chang-Sup;Yeoun, Poung-Sik;Park, Suk-Hee;Koo, Wan-Hae
    • Journal of Environmental Science International
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    • v.22 no.11
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    • pp.1519-1527
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    • 2013
  • We have researched the image of different forest species by asking those who use these forests how they feel when enjoying them for their various purposes. We surveyed five different forest areas, these were a pine forest a korean pine forest a cypress forest a broad leafed forest and a mixed forest. We asked 806 people how these forests made them feel and what they thought was the image of these forests. We offered them a choice of 18 pairs of adjectives to describe how they felt. We used the SD Scale and discovered 4 different factors. A feeling of comfort and freshness and a feeling of order and space. There was also a feeling of intimacy with nature. Each forest gave out its own feeling and image. comfort and freshness was felt by those in the pine forest, the korean pine forest, the broad leafed forest and the mixed forest. A Feeling of order and space was felt in the korean pine forest. Intimacy was felt in the pine forest, broad leafed forest and the mixed forest.

Analysis of Forest Environmental Factors on Torrent Erosion control work area in Gyeongsangnam-do - Focus on Erosion Control Dam and Stream Conservation - (경남지역 야계사방사업지의 산림환경특성 분석 - 사방댐 및 계류보전사업을 중심으로 -)

  • Kang, Min-Jeng;Kim, Ki-Dae;Oh, Kang-San;Park, Jin-Won;Park, Jae-Hyeon
    • Journal of agriculture & life science
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    • v.50 no.5
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    • pp.111-120
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    • 2016
  • The objective of this study was to provide basic information for selecting the right timing and the right place of erosion control of stream on Gyeongsangnam-do. In order to achieve this objective, a total of 526 erosion control dams and 230 mountains stream conservation facilities on the constructed places and construction planned places for the erosion control were investigated on site, forest physiognomy, and hydrologic conditions. The erosion control dams and mountain stream conservation facilities were mostly constructed in the area, which has the sedimentary rock, 200-400m of altitude, a slope of 21~30°, and II of landslide hazard map. Among the forest environmental factors, it was only similar to the construction frequency in the areas that have small diameter class, III age class. Also, we investigated the hydrological environmental factors that determine the size and numbers of erosion control dam. The places constructed to the highest frequency were below 50ha in the area, 2.1~4.0km/㎢ of drainage density, longitudinal water system, 61~90mm of maximum precipitation per hour, and 201~300mm of day maximum precipitation. As the results, the sites and floodgate conditions between the constructed places and stream conservation facilities for the erosion control showed to be very similar. Therefore, these results indicate that the erosion control of the stream of the areas, which have the disruption of mountain peaks and the high erosion risk areas, should be used on both the erosion control dam and stream conservation facilities.

Application and Development of Carbon Emissions Factors for Deciduous Species in Republic of Korea - Robinia pseudoacacia, Betula platyphylla, and Liriodendron tulipifera - (국내 활엽수종의 탄소배출계수 개발 및 적용 - 아까시나무, 자작나무, 백합나무를 대상으로 -)

  • Lee, Sun Jeoung;Yim, Jong Su;Kang, Jin Take;Kim, Raehyun;Son, Yowhan;Park, Gawn Su;Son, Yeong Mo
    • Journal of Climate Change Research
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    • v.8 no.4
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    • pp.393-399
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    • 2017
  • According to the United Nations Framework Convention on Climate Change (UNFCCC), all parties have to submit the national GHG inventory report. Estimating carbon stocks and changes in Land Use, Land-Use Changes and Forestry (LULUCF) needs an activity data and emission factors. So this study was conducted to develop carbon emission factor for Robinia pseudoacacia L., Betula platyphylla var. japonica, and Liriodendron tulipifera. As a result, the basic wood density ($g/cm_3$) was 0.64 for R. pseudoacacia, 0.55 for B. platyphylla, and 0.46 for L. tulipifera. Biomass expansion factor was 1.47 for R. pseudoacacia, 1.30 for B. platyphylla, and 1.24 for L. tulipifera. Root to shoot ratio was 0.48 for R. pseudoacacia, 0.29 for B. platyphylla, and 0.23 for L. tulipifera. Uncertainty of estimated emission factors on three species ranged from 3.39% to 27.43% within recommended value (30%) by IPCC. We calculated carbon stock and change using these emission factors. Three species stored carbon in forest and net $CO_2$ removal was $1,255,398\;t\;CO_2/yr$ during 5 years. So we concluded that our result could be used as emission factors for national GHG inventory report on forest sector.

A Structural Relationship between Place Attachment and Environmental Factor to Temple Forest Trail in Gyeongju National Park (경주국립공원 사찰숲길에 있어 장소애착과 환경요인의 구조적 관계)

  • Lee, Duk-Jae;Kwon, Tae-Ho
    • Korean Journal of Environment and Ecology
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    • v.26 no.2
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    • pp.283-291
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    • 2012
  • The aim of this study is to explore the structural relationship between recognition to environmental factor and place attachment of the users of temple forest trail in Gyeongju National Park, and to suggest political implications on conservation management of National Park from the viewpoint of landscape attachment. Survey with a structured questionnaire was implemented to visitors to the Bulkuksa, a representative temple in Geyongju National Park. Structural equation model was developed from the analysis of collected data. Results showed that place dependence positively affected place attachment in significance, whereas place identity did not significantly affect place attachment. Place attachment was affected rather by place dependence(path coefficient=0.55). Place attachment positively affected the recognition of environmental factors in significance. Landscape use factors compared to facility use factors were affected rather by place attachment(path coefficient=1.01). This result verified the importance of landscape factors of National Park, and suggested a management plan focused on the landscape conservation of forest trail of traditional temple.