• Title/Summary/Keyword: forest site productivity

Search Result 68, Processing Time 0.025 seconds

Estimation of Stand Growth and CO2 Removals for Juglans mandshurica Plantations in ChungJu, Chungcheongbuk-do in Korea (충북 충주지역 가래나무의 임목생장량 및 이산화탄소 흡수량 추정)

  • Son, Yeong Mo;Kim, Rae Hyun;Kim, Young Hwan;Lee, Kyeong Hak
    • Journal of Korean Society of Forest Science
    • /
    • v.98 no.6
    • /
    • pp.646-651
    • /
    • 2009
  • In this study, it was intended to prepare a stem volume table (with or without bark) and a stand yield table for Juglans mandshurica, plantations in Chungju, located in Chungcheongbuk-do, Korea. For the calculation of stem volume, we applied Kozak's growth model, which showed the best fitness index (97%). With this model, it was able to prepare the first yield table for Juglans mandshurica in Korea. Site index model, an indicator of forest productivity, was derived by using the Chapman-Richard model, in which the basic stand age was set to 30 years. The resulted site index ranged between 16 and 22. Based on the yield table of Juglans mandshurica resulted from this study, the volume for a 70-year-old stand with a midium site index class was estimated to be $238m^3/ha$, which is $100m^3/ha$ higher than the volume estimated from the yield table of Quercus acutissima. The yield table of oak trees has been used in the estimation of most broadleaf stands in Korea. However, the result of this study indicated that it is necessary to generate a stand yield table for each broadleaf species. The annual $CO_2$ removals of 30-year-old Juglans mandshurica plantations in the ChungJu region was estimated to be $5.84tCO_2/ha$. The stem volume and stand yield table of Juglans mandshurica plantation resulted from this study would provide a good information in decision making for forest management in ChungJu region.

The Yarding Productivity and Cost of Cable Yarding Operation by Yarder Attached on Trator -Using the Chuncheon Tower-yarder - (트랙터부착 집재기를 이용한 집재작업 분석 -춘천집재기를 중심으로 -)

  • Han, Won Sung;Han, Han-Sup;Kim, Yeong-Suk;Shin, Man Yong
    • Journal of Korean Society of Forest Science
    • /
    • v.97 no.6
    • /
    • pp.641-649
    • /
    • 2008
  • This study was conducted to evaluate the productivity and the operational costs of the Chuncheon Tower-yarder, a skyline yarding system used in Korea. Detailed time study data were collected from 4 thinning sites in Japanese larch (Larix leptolepis) stands; one site for uphill yarding and three sites for downhill yarding. This study derived regression models to estimate the average cycle time (sec.) for uphill and downhill yarding. The average yarding cost was $12,844won/m^3$ for uphill yarding, while downhill yarding cost was $13,221won/m^3$. The average yarding time was 239 sec/cycle for uphill yarding, while downhill average yarding time was 274 sec/cycle. We found that uphill yarding productivity was higher when the operation system was examined under the same work conditions (i.e. standardized comparison) except yarding directions for both uphill yarding and downhill yarding.

A Study on Effect of Forest Fire on Change of Soil Properties (산화에 의한 토양특성 변화에 관한 연구)

  • Park, Gwan Soo;Lee, Sung Woo
    • Korean Journal of Agricultural Science
    • /
    • v.27 no.2
    • /
    • pp.95-100
    • /
    • 2000
  • This study was carried out to estimate the effect of forest fire on physical and chemical properties of soil. The forest fire was in April 1997 in pinus densiflora dominant forest at Chungju of Chungbuk. After forest fire, dead trees were not cut. Soil samples were collected at 0-5, 5-10, and 10-20cm soil depths in November 1998 from the burned and unburned sites. The analyzed factors were soil organic matter, total N, available P, exchangeable K, Ca, and Mg, and CEC, pH, bulk density, and moisture content. There was no forest floor in burned site, but unburned site has the forest floor of 4cm thick. There were no differences in soil organic matter, total N, available P, exchangeable K, Ca, and Mg, and CEC, pH, bulk density, moisture content in all soil depth, between burned and unburned sites, except in available P in 5-10cm soil depth. Forest fire had not changed the physical and chemical soil properties in this study. However, burning of vegetation and forest floor organic matter may have adverse influence on long-term site productivity.

  • PDF

Comparison of Carbon Storage between Forest Restoration of Abandoned Coal Mine and Natural Vegetation Lands (폐탄광 산림복원지와 자연식생지의 탄소저장량 비교)

  • Kim, So-Jin;Jung, Yu-Gyeong;Park, Ki-Hyung;Kim, Ju-Eun;Bae, Jeong-Hyeon;Kang, Won-Seok
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.26 no.5
    • /
    • pp.33-46
    • /
    • 2023
  • In this study, carbon storage in the aboveground biomass, litter layer, and soil layer was calculated for abandoned mining restoration areas to determine the level of carbon storage after the restoration project through comparison with the ecological reference. Five survey sites were selected for each abandoned mining restoration area in Boryeong-si, Chungcheongnam-do, and the ecological reference that can be a goal and model for the restoration project. The carbon storage in the restoration area was 0~21.3Mg C ha-1, the deciduous layer 3.3~6.0Mg C ha-1, and the soil layer(0-30cm) 8.3~35.1Mg C ha-1, showing a significant difference in carbon storage by target site. The total carbon storage was between 6.1 and 35.3% of the ecological reference, with restoration area ranging from 14.0 to 62.4 Mg C ha-1. The total carbon storage in the restoration area and the ecological reference differed the most in the aboveground biomass and was less than 12%. Based on these results, forest restoration area need to improve the carbon storage of forests through continuous management and monitoring so trees can grow and restore productivity in the early stages of the restoration project. The results of this study can be used as primary data for preparing future forest restoration indicators by identifying the storage of abandoned mining restoration areas.

An Analysis of the Operational Productivity and Cost for the Utilization of Forest-biomass(II) - the Analysis of Operational Cost - (산림바이오매스 이용을 위한 산림작업 공정 및 비용 분석(II) - 작업비용 분석 -)

  • Mun, Ho-Seong;Cho, Koo-Hyun;Park, Sang-Jun
    • Journal of Korean Society of Forest Science
    • /
    • v.104 no.2
    • /
    • pp.230-238
    • /
    • 2015
  • This study was analyzed the operational cost of logging and chipping operations in order to develop the efficient logging operation system for the utilization of forest-biomass. Analysis of the operational cost of logging operation systems, the operation system D which include chain saw, tower-yarder, mini-forwarder and truck was calculated the lowest cost to be $68,498Won/m^3$. In the utilization of forest-biomass, the operation system E which include chipping by mini-chipper at the site, forwarding of chips by mini-forwarder, transportation of chips by truck was estimated to be 90,770 Won/Ton. Thus, These results are determined as an effective operating system for logging operation and the utilization of forest-biomass.

Assessment of Ecosystem Productivity and Efficiency using Flux Measurement over Haenam Farmland Site in Korea (HFK) (플럭스 관측 기반의 생태계 생산성과 효율성 평가: 해남 농경지 연구 사례)

  • Indrawati, Yohana Maria;Kim, Joon;Kang, Minseok
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.20 no.1
    • /
    • pp.57-72
    • /
    • 2018
  • Time series analysis of tower flux measurement can be used to build quantitative evidence for the achievement of climate-smart agriculture (CSA). In this study, we have assessed the first objective of CSA (regarding ecosystem productivity and efficiency) for rice paddy-dominated heterogeneous farmland. A set of quantitative indicators were evaluated by analysing the time series data of carbon, water and energy fluxes over the Haenam farmland site in Korea (HFK) during the rice growing seasons from 2003 to 2015. Four different varieties of rice were cultivated during the study period in chronological order of Dongjin No. 1 (2003-2008), Nampyung (2009), Onnuri (2010-2011), and Saenuri (2012-2015). Overall at HFK, gross primary productivity (GPP) ranged from 800 to $944g\;C\;m^{-2}$, water use efficiency (WUE) ranged from 1.91 to $2.80g\;C\;kg\;H_2O^{-1}$, carbon uptake efficiency (CUE) ranged from 1.06 to 1.34, and light use efficiency (LUE) ranged from 0.99 to $1.55g\;C\;MJ^{-1}$. Among the four rice varieties, Dongjin No. 1-dominated HFK showed the highest productivity with higher WUE and LUE, but comparable CUE. Considering the heterogeneous vegetation cover at HFK, a rule of thumb comparison suggested that the productivity of Dongjin No1-dominated HFK was comparable to those of monoculture rice paddies in Asia, whereas HFK was more efficient in water use and less efficient in carbon uptake. Saenuri-dominated HFK also produced high productivity but with the growing season length longer than Dongjin No.1. Although the latter showed better traits for CSA, farmers cultivate Saenuri because of higher pest resistance (associated with adaptability and resilience). This emphasizes the need for the evaluation of other two objectives of CSA (i.e. system resilience and greenhouse gas mitigation) for complete assessment at HFK, which is currently in progress.

Anticipation of the Future Suitable Cultivation Areas for Korean Pines in Korean Peninsula with Climate Change (기후변화를 고려한 잣나무의 미래 적지적수 변화 예측)

  • Choi, Jaeyong;Lee, Peter Sang-Hoon;Lee, Sanghyuk
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.18 no.1
    • /
    • pp.103-113
    • /
    • 2015
  • Korean pines(Pinus koraiensis) are one of the major plantation species in the Republic of Korea and their natural habitats range from Japan and China to Siberia. The seed of Korean pines, pine nuts, are well know for good food reserves. Due to the global changes which drive the Korean peninsula into the semi-tropical climate, current plantations and natural habitats of Korean pines are faced with the change in the environmental conditions to some extent. To anticipate suitable sites for Korean pines in the future, the location of Korean pines were extracted from the 'Map of suitable trees on a site' that provides the map of suitable trees on a site considering tree species for timber and special uses, and then MaxEnt modelling was used for generating a prediction map on the basis of statistical analysis. As a result, the order of predicted suitable sites were Kangwon-do, Kyungsangbuk-do and Chungcheongbuk-do provinces and sites with high elevation within those provinces were considered most suitable in common. The prediction map of suitable sites for Korean pines presented that suitable sites in the future decreased by 72.2% by 2050's and almost disappeared with a decrease of 92.1% by 2070's on a nationwide scale. In relation to the major production regions of pine nuts in South Korea - Gapyung gun and Yangpyung gun, Kyunggi province and Hongcheon gun, Kangwon province, suitable sites within their areas were predicted to increase by 2050's but become extinct in South Korea by 2070's. To establish a long-term countermeasures against the improvement on forest productivity quality in terms of managing national food security, the result from this study can be considered as a firm basis of predicting plantation suitability. Also, it can be used to predict the changes in supply of forest products and thereby market values in accordance with climate change scenarios.

Work Load of Felling Work Using Chain Saw in Japanese Larch Plantation Site (체인톱을 이용(利用)한 낙엽송(落葉松) 벌목작업(伐木作業)에서의 작업강도분석(作業强度分析))

  • Lee, Joon Woo;Park, Bum Jin;Kim, Jae Won;Song, Tae Young
    • Journal of Korean Society of Forest Science
    • /
    • v.87 no.2
    • /
    • pp.121-130
    • /
    • 1998
  • This study was carried out to investigate working time, productivity, and heart rate during thinning using chain saw in Japanese larch(Larix leptolepis) plantation site for analysis of physical work load, and to investigate maximal oxygen uptake of worker for analysis of maximal work capacity. The real working time was 366 minutes in a day ; about 192 minutes in the a.m., 174 minutes in the p.m.. The ratio of real working time per total working time was approximately 90%. The rate of moving(Mo) to real working times was 26.3, which was the largest one of work elements. Average maximal oxygen uptake, as an asset of personnel performance, was $2.42{\ell}/min$($46.5m{\ell}/kg/min$). During the real working time, average productivity, the mean rate of increase of heart rate, and the mean work load index was $2.62m^3/hr$, 93.2%, and 41.9%, respectively.

  • PDF

Characteristics of Soil Disturbance Caused by Passages of Harvester and Forwarder in Cut-to-Length Harvesting Operations (단목생산작업에 있어서 하베스터와 포워더의 임내주행에 따른 토양교란 특성)

  • Han, Sang-Kyun;Lee, Kyeong-Cheol;Oh, Jae-Heun;Mun, Ho-Seong;Lee, Sang-Tae;Choi, Yun-Sung;Choi, Byoung-Koo
    • Journal of Korean Society of Forest Science
    • /
    • v.108 no.1
    • /
    • pp.67-76
    • /
    • 2019
  • With an increasing demand of timber production, the use of heavy machinery in forest management has significantly increased, causing the changes of soil physical properties and the decline of long-term site productivity. This study was conducted to evaluate the effects of logging slash (non-slash, slash $7.3kg/m^2$, and slash $11.5kg/m^2$) and machine passes(harvester 1 pass and forwarder 1 to 10 passes) on soil physical properties at 10 cm, 20 cm and 30 cm soil depths in harvester and forwarder operations and also to estimate the degree of soil surface disturbance. The results indicated that soil bulk density in the non-slash treatment site increased 10 %~29 % (25~139 % in soil penetration resistance) at all soil depths, compared with the slash treatment site(slash $11.5kg/m^2$). Therefore, the creation of a slash mat could be an effective way to minimize the changes of soil physical properties. In addition, 92 % of total soil compaction in slash treatment site was created within harvester 1 pass and forwarder 5 passes. In non-slash treatment site, 84 % of total soil compaction was created within first harvester and forwarder passes. The results showed that slash treatment was effective to reduce soil compaction caused by machine passes and also it is necessary to create designed forwarding trails for minimizing soil compaction area at timber harvesting sites.

Effect of micro-environment in ridge and southern slope on soil respiration in Quercus mongolica forest

  • Lee, Jae-Seok
    • Journal of Ecology and Environment
    • /
    • v.42 no.4
    • /
    • pp.210-218
    • /
    • 2018
  • Background: Soil respiration (Rs) is a major factor of the absorption and accumulation of carbon through photosynthesis in the ecosystem carbon cycle. This directly affects the amount of net ecosystem productivity, which affects the stability and sustainability of the ecosystem. Understanding the characteristics of Rs is indispensable to scientifically understand the carbon cycle of ecosystems. It is very important to study Rs characteristics through analysis of environmental factors closely related to Rs. Rs is affected by various environmental factors, such as temperature, precipitation, soil moisture, litter supply, organic matter content, dominant plant species, and soil disturbance. This study was conducted to analyze the effects of micro-topographical differences on Rs in forest vegetation by measuring the Rs on the ridge and southern slope sites of the broadly established Quercus mongolica forest in the central Korean area. Method: Rs, Ts, and soil moisture data were collected at the southern slope and ridge of the Q. mongolica forest in the Mt. Jeombong area in order to investigate the effects of topographical differences on Rs. Rs was collected by the closed chamber method, and data collection was performed from May 2011 to October 2013, except Winter seasons from November to April or May. For collecting the raw data of Rs in the field, acrylic collars were placed at the ridge and southern slope of the forest. The accumulated surface litter and the soil organic matter content (SOMC) were measured to a 5 cm depth. Based on these data, the Rs characteristics of the slope and ridge were analyzed. Results: Rs showed a distinct seasonal variation pattern in both the ridge and southern slope sites. In addition, Rs showed a distinct seasonal variation with high and low Ts changes. The average Rs measurements for the two sites, except for the Winter periods that were not measured, were $550.1\;mg\;CO_2m^{-2}h^{-1}$ at the ridge site and $289.4\;mg\;CO_2m^{-2}h^{-1}$ at the southern slope, a difference of 52.6%. There was no significant difference in the Rs difference between slopes except for the first half of 2013, and both sites showed a tendency to increase exponentially as Ts increased. In addition, although the correlation is low, the difference in Rs between sites tended to increase as Ts increased. SMC showed a large fluctuation at the southern slope site relative to the ridge site, as while it was very low in 2013, it was high in 2011 and 2012. The accumulated litter of the soil surface and the SOMC at the depth range of 0~5 cm were $874g\;m^{-2}$ and 23.3% at the ridge site, and $396g\;m^{-2}$ and 19.9% at the southern slope site. Conclusions: In this study, Rs was measured for the ridge and southern slope sites, which have two different results where the surface litter layer is disturbed by strong winds. The southern slope site shows that the litter layer formed in autumn due to strong winds almost disappeared, and while in the ridge site, it became thick due to the transfer of litter from the southern slope site. The mean Rs was about two times higher in the ridge site compared to that in the southern slope site. The Rs difference seems to be due to the difference in the amount of litter accumulated on the soil surface. As a result, the litter layer supplied to the soil surface is disturbed due to the micro-topographical difference, as the slope and the change of the community structure due to the plant season cause heterogeneity of the litter layer development, which in turn affects SMC and Rs. Therefore, it is necessary to introduce and understand these micro-topographical features and mechanisms when quantifying and analyzing the Rs of an ecosystem.