• Title/Summary/Keyword: forest area changes

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Prediction of Land Use/Land Cover Change in Forest Area Using a Probability Density Function

  • Park, Jinwoo;Park, Jeongmook;Lee, Jungsoo
    • Journal of Forest and Environmental Science
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    • v.33 no.4
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    • pp.305-314
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    • 2017
  • This study aimed to predict changes in forest area using a probability density function, in order to promote effective forest management in the area north of the civilian control line (known as the Minbuk area) in Korea. Time series analysis (2010 and 2016) of forest area using land cover maps and accessibility expressed by distance covariates (distance from buildings, roads, and civilian control line) was applied to a probability density function. In order to estimate the probability density function, mean and variance were calculated using three methods: area weight (AW), area rate weight (ARW), and sample area change rate weight (SRW). Forest area increases in regions with lower accessibility (i.e., greater distance) from buildings and roads, but no relationship with accessibility from the civilian control line was found. Estimation of forest area change using different distance covariates shows that SRW using distance from buildings provides the most accurate estimation, with around 0.98-fold difference from actual forest area change, and performs well in a Chi-Square test. Furthermore, estimation of forest area until 2028 using SRW and distance from buildings most closely replicates patterns of actual forest area changes, suggesting that estimation of future change could be possible using this method. The method allows investigation of the current status of land cover in the Minbuk area, as well as predictions of future changes in forest area that could be utilized in forest management planning and policymaking in the northern area.

Changes of the Forest Types by Climate Changes using Satellite imagery and Forest Statistical Data: A case in the Chungnam Coastal Ares, Korea (위성영상과 임상통계를 이용한 충남해안지역의 기후변화에 따른 임상 변화)

  • Kim, Chansoo;Park, Ji-Hoon;Jang, Dong-Ho
    • Journal of Environmental Impact Assessment
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    • v.20 no.4
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    • pp.523-538
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    • 2011
  • This study analyzes the changes in the surface area of each forest cover, based on temperature data analysis and satellite imagery as the basic methods for the impact assessment of climate change on regional units. Furthermore, future changes in the forest cover are predicted using the double exponential smoothing method. The results of the study have shown an overall increase in annual mean temperature in the studied region since 1990, and an especially increased rate in winter and autumn compared to other seasons. The multi-temporal analysis of the changes in the forest cover using satellite images showed a large decrease of coniferous forests, and a continual increase in deciduous forests and mixed forests. Such changes are attributed to the increase in annual mean temperature of the studied regions. The analysis of changes in the surface area of each forest cover using the statistical data displayed similar tendencies as that of the forest cover categorizing results from the satellite images. Accordingly, rapid changes in forest cover following the increase of temperature in the studied regions could be expected. The results of the study of the forest cover surface using the double exponential smoothing method predict a continual decrease in coniferous forests until 2050. On the contrary, deciduous forests and mixed forests are predicted to show continually increasing tendencies. Deciduous forests have been predicted to increase the most in the future. With these results, the data on forest cover can be usefully applied as the main index for climate change. Further qualitative results are expected to be deduced from these data in the future, compared to the analyses of the relationship between tree species of forest and climate factors.

Change of Subalpine Coniferous Forest Area over the Last 20 Years (아고산 침엽수림 분포 면적의 20년간 변화 분석)

  • Kim, Eun-Sook;Lee, Ji-Sun;Park, Go-Eun;Lim, Jong-Hwan
    • Journal of Korean Society of Forest Science
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    • v.108 no.1
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    • pp.10-20
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    • 2019
  • The purpose of this study is to identify the long-term area changes in the subalpine coniferous forests in Korea in order to understand the changes in the subalpine forest ecosystems vulnerable to climate change. We analyzed 20 years of time-series Landsat satellite images (mid 1990s, mid 2010s) for change detection of coniferous forests and compared with the long term changes of climate information to identify their relationship in the study area. As a result, the area of coniferous forests in the study region decreased by 25% over 20 years. The regions with largest changes are Seoraksan, Baegunsan-Hambaeksan-Jangsan, Jirisan, and Hallasan. The region with the largest decrease in area was Baegunsan (reduced area: 542 ha), and the region with large decrease in area and the largest rate of decrease was Hallasan (rate of decrease: 33.3%). As the Jeju region has the most rapid temperature rise, it is projected that Hallasan is the most vulnerable forest ecosystem affected by climate change. The result of this study shows that from a long-term perspective the overall coniferous forests in the subalpine region are declining, but the trend varies in each region. This national and long-term information on the change of coniferous forests in the subalpine region can be utilized as baseline data for the detailed survey of endangered subalpine coniferous trees in the future.

Study on Timber Yield Regulation Method using Probability Density Function (확률밀도함수를 이용한 목재수확조절법 연구)

  • Park, Jung-Mook;Lee, Jung-Soo;Lee, Ho-Sang;Park, Jin-Woo
    • Journal of Korean Society of Forest Science
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    • v.109 no.4
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    • pp.504-511
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    • 2020
  • This study estimated planned felling volumes to set targets for management planning of nationwide country-owned forests. Estimates were made using timber harvest prediction methods that use probability density functions, including area weighting (AW), area ratio weighting (ARW), and sample area change ratio weighting (SCRW). Country-owned forest areas in 2010 and 2015 were used to estimate planned felling volumes, as shown in basic forest statistics, and calculations were made assuming that the felling areas were the changes in the forest area over the 5-year period. For the age classes of V-VI, the average felling ages for AW, ARW, and SCRW were 5.41, 5.56, and 5.37, respectively, and the felling areas were 594,462, 586,704, and 580,852 ha, respectively, with ARW reaching closest to the actual changes. The actual changes in the areas and chi-squared test results were most stable with the SCRW method. This study showed that SCRW was more adequate than AW and ARW as a method to predict timber harvests for forest management planning.

An Analysis on the Structural Changes of Rural Land Use According to Urbanization (도시화에 따른 농촌토지이용구조변화 분석)

  • Hwang, Han-Cheol;Go, Young-Bae
    • Journal of Korean Society of Rural Planning
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    • v.13 no.2
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    • pp.85-92
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    • 2007
  • This study aims to show how the urbanization of Korea has progressed for the last three decades, what its characteristics are, and how rural land use has changed by the national and district(cities and counties) level. The land use changes accompanying to the urbanization is analyzed through 3 indicators such as urbanization rate, the rate of cultivated and forest land and the rate of urbanized area. The statistical data are 30 years from 1976 to 2005 for time series analysis by the national level, and are for the two years of 1995 and 2005 by the district level. The relationship between urbanization and land use changes in the national level is analyzed using statistical analysis(Correlation Analysis). In order to analyze the dynamic and spatial urbanization and land use changes effectively in the district level, Z-score, Paired T-test, Correlation Analysis, Analysis of Variance and Chi-squire Test are used. The results show negative correlation between urbanization rate and the rate of cultivated and forest land, and positive correlation between urbanization rate and the rate of urbanized area respectively. In the aspect of the change of urbanization rate, four categories are examined. In addition, four types are characterized on the basis of the rate of cultivated and forest land and the rate of urbanized area between 1995 from 2005.

A Study of the Employment Policies and Outlooks of the Forest and Green Jobs Area (산림 및 녹색산업분야 일자리 고용 전망에 관한 연구)

  • Shinn, Yun Ho
    • Journal of Agricultural Extension & Community Development
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    • v.19 no.3
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    • pp.673-697
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    • 2012
  • The purpose of this study was to describe the policies and outlooks of the green jobs including the forest area. The Methodology of the study was mainly on literature review and second data used and analyzed to get the result. The findings of the study was the manpower of Green Jobs was 2.5% in 2009, it should be expected to 2.9 percent in 2016, and overall of the green jobs and forest area of the outlooks should be increased from 46 percent to 56 percent in each sector of green and forest area. The climate changes and environmental pollutions would push the conditions of new green jobs in forest area as well as waste-based industry. The suggestions were made based on the study of which one is policy-making should be prepared for creating Green Jobs and the forest area.

Effects of Water Level Change on Wetland Vegetation in the Area of Riparian Forest for Dam Construction Period -Focused on the Hantan River Dam- (댐 건설 기간 수위변화가 하반림 일대 습지 식생에 미치는 영향 -한탄강댐을 사례로-)

  • Park, Hyun-Chul;Lee, Jung-Hwan;Lee, Gwan-Gyu
    • Journal of Forest and Environmental Science
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    • v.30 no.1
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    • pp.76-84
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    • 2014
  • This study was performed to monitor the effects of water level change on changes of landscape, vegetation community, and species diversity of riparian forest. Hantan river dam, study area, has been constructed in the area of Chansoo-myeon, Pocheon-si and Yeoncheon-eup, Yeoncheon-gun, Gyeonggi-do, which is a dam for flood control only in flooding season. Landscape changes were notable after the construction of coffer dam, and the changes were caused by water level increase in areas of riparian forests which consisted of mainly withered willow as a dominant species in the flooding season. It changed vegetation communities of riparian forest from Phragmites japonica and Salix koreensis to Phragmites japonica. Species diversity index was lowest in 2010 when the coffer dam was constructed and showed an increasing trend later. Thus, this study is well in agreement with a previous report that plants of the genus Salix wither by muddy water during flooding and also suggests, controlling water level of river and prediction of water level change's effects should be considered when any facilities are planned.

Changes of Concentration of Al, Mn and Ni in Throughfall, Stemflow and Rainfall (수관통과우, 수간류 및 임외우에서 Al, Mn 및 Ni의 농도 변화)

  • 이총규;김우룡;김종갑
    • The Korean Journal of Ecology
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    • v.22 no.5
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    • pp.295-298
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    • 1999
  • This study was carried out to investigate the changes in concentration of heavy metals in throughfall, stemflow and rainfall at the survey area. The Al concentration of Pinus thunbergii forest was 1.3 times higher than those of Quercus acutissima forest at industrial area, and 2.1 times higher at urban area. The Al concentration of stemflow was 2.3 times and 113 times, 4.8 times and 55 times, respectively, higher than those of throughfall, and rainfall at both industrial and urban area. The Al concentration of rainfall was lower at industrial and urban area. The Mn concentration of Pinus thunbergii forest was 2.4 times higher than those of Quercus acutissima forest at urban area. Heavy metal concentrations in rain water were the higher in stemflow, and in the order of throughfall and rainfall. Seasonal changes of heavy metal concentration were the highest on December at industrial area, and were higher in the order of March>June>August. Seasonal changes were not remarkable at urban area. Heavy metal concentrations were higher in the order of Al>Mn>Ni at industrial area, and Mn>Al>Ni at urban area.

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Long Term Changes of the Amount of Surface Runoff in Forest Fire Area (산불발생지에 있어서 표면유출수량의 장기적인 변화에 관한 연구)

  • Ma, Ho-Seop;Jeong, Won-Ok
    • Journal of Korean Society of Forest Science
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    • v.98 no.4
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    • pp.458-463
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    • 2009
  • The purpose of this study was to evaluate the changes of surface runoff by comparisons between burned and unburned area after forest fire. The amount of surface runoff in burned area was more high 1.72 times in the year of fire, 1.44 times in one year later, 1.38 times in five years later and 1.16 times in ten years later than those of unburned area. Therefore, surface runoff in the burned area almost tended to be stabilized like unburned area ten year later after forest fire. The most affecting factors on the amount of surface runoff in burned and unburned area were number of unit rainfall, number of rainfall accumulated and unit rainfall. But coverage was shown to mitigate the amount of surface runoff in burned and unburned area.