• Title/Summary/Keyword: Forest Degradation

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Screening of Organo Phosphorus Insecticide Fenitrothion-Degrading Microorganisms (유기인계 살충제 fenitrothion 분해미생물 탐색)

  • Choi, Hyuek;Kim, Bok-Jin;Bae, Do-Yong;Lee, Young-Deuk;Kang, Sun-Chul
    • Korean Journal of Environmental Agriculture
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    • v.17 no.3
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    • pp.279-285
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    • 1998
  • Fenitrothion-degrading microorganisms were isolated from 124 sampling sites of paddy, upland, forest and polluted soil, and wastewater. A total of 1,071 strains were isolated from each selective medium supplemented with 50mg/l of fenitrothion - nutrient agar (NA) 601, potato dextrose agar (PDA) 201, Actinomycetes isolation agar (AIA) 168 and basal salt medium (BSM) 101, respectively. Twenty-eight effective strains of them, which showed more than 80% degradation of fenitrothion by the gasliquid chromatography(GLC) analysis. were successfully selected from each liquid culture supplemented with 50mg/l of fenitrothion - NB 12(upland soil 3, paddy soil 3, forest soil 2, polluted soil 4), PDB 8(upland soil 1, paddy soil 2, forest soil 2, polluted soil 3) and PSB 8(upland soil 1, forest soil 1, polluted soil 6), respectively. Four strains - NPal, NFol, PFol and BPol, which have the most powerful degradation activity were finally selected among 28 fenitrothion-degrading microorganisms based on the degradation rate at the concentration of 100mg/l fenitrothion in enrichment media.

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Forest Transition in Korea:Trends, Characteristics and Implications (한국의 산림 변천:추이, 특징 및 함의)

  • Bae, Jae Soo
    • Journal of Korean Society of Forest Science
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    • v.98 no.6
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    • pp.659-668
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    • 2009
  • Time series data on forest resources and population over the period from 1927 to 2007 were constructed and analyzed in order to identify trends and characteristics of forest transition in Korea. Korean forest transition could be classified into three phases in terms of the average annual growing stock of forest; forest degradation period (1927-1952), forest stagnation period (1953-1972) and forest growth period (1973-2007). Over the past 80 years forest area decreased 0.05% each year. The decreasing rate was very low, especially considering rapid economic growth and increased population of Korea with over 60% of forest cover. Growing stock per hectare significantly increased from $5.6m^3$ in 1952 to $97.8m^3$ in 2007, or 17.5 times during 1952 to 2007. Despise of increasing population and rapid economic growth, in particular, growing stock per capita has increased from $1.7m^3$ in 1952 to $12.9m^3$ in 2005 and un-stocked forest area decreased from 3,315 thousand ha to 165 thousand ha during the same period. In this regard, Korea represents a case of modern forest growth. Among 56 countries with more than 10 million of population and 10% or more of forest cover over the period 1990 to 2005, Korea is classified as a country which has high forest cover but low deforestation rate. Also, Korea is the only developing country which has 50% or more of forest cover and shows a below average deforestation rate.

Households' Characteristics, Forest Resources Dependency and Forest Availability in Central Terai of Nepal

  • Panta, Menaka;Kim, Kyehyun;Lee, Cholyoung
    • Journal of Korean Society of Forest Science
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    • v.98 no.5
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    • pp.548-557
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    • 2009
  • For centuries, forests have been a key component of rural livelihood. They are important both socially and economically in Nepal. Firewood and fodder are the basic forest products that are extracted daily or weekly basis in most of the rural areas in Nepal. In this study, a field survey of 100 households was conducted to examine the degree of forest dependency and forest resource availability, households' livelihood strategy and their relationship with forest dependency in Chitwan, Nepal. A household' response indexes were constructed, Gini coefficient, Head Count Poverty Index (HCI) and Poverty Gap Index (PGI) were calculated and one way ANOVA test was also performed for data analysis. Data revealed that 82/81% of all households were constantly used forest for firewood and fodder collection respectively while 42% of households were used forest or forest fringe for grazing. The Forest Product Availability Indexes (FPAI) showed a sharp decline of forest resources from 0.781 to 0.308 for a 20-yr time horizon while timber wood was noticeably lowered than the other products. Yet, about 33% of households were below the poverty threshold line with 0.0945 PGI. Income distribution among the household showed a lower Gini coefficient 0.25 than 0.37 of landholdings size. However, mean income was significantly varies with F-statistics=246.348 at P=0.05 between income groups (rich, medium and poor). The extraction of firewood, fodder and other forest products were significantly different between the income group with F-statistics=16.480, 19.930, 29.956 at P=0.05 respectively. Similarly, landholdings size and education were also significantly different between the income groups with F-statistics=4.333, 5.981 at P=0.05 respectively. These findings suggested that income status of households was the major indicator of forest dependency while poor and medium groups were highly dependent on the forests for firewood, fodder and other products. Forest dependency still remains high and the availability of forest products that can be extracted from the remaining forestlands is decreasing. The high dependency of households on forest coupled with other socioeconomic attributes like education, poverty, small landholders and so on were possibly caused the forest degradation in Chitwan.Therefore, policy must be directed towards the poor livelihood supporting agenda that may enhance the financial conditions of rural households while it could reduce the degree of forest dependency inspired with other income generating activities in due course.

Spatial Relationship of Suburb, Road and River in respect to Forest Canopy Density Change Using GIS and RS

  • Pantal, Menaka;Kim, Kye-Hyun
    • 한국공간정보시스템학회:학술대회논문집
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    • 2005.11a
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    • pp.257-270
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    • 2005
  • Many studies states that improperly uprising of infrastructure may cause leading the forest degradation and canopy reduction in many tropical forest of Asian countries. Other studies revealed that habitat destruction and fragmentation, edge effects, exotic species invasions, pollution are provoked by roads. Similarly, environmental effects of road construction in forests are problematic. Similarly, many researches have been indicated that roads have a far greater impact on forests than simply allowing greater access for human use. Moreover, people using river as means of transportation hence illegal logging and felling cause canopy depletion in many countries. Therefore, it is important to comprehend the study about spatial relation of road, river and suburb followed by temporal change of forest canopy phenomena. This study also tried to examine the effect of road, river and suburb in forest canopy density change of Terai forest of Nepal from you 1988 to 2001. So, Landsat TM88, 92 and 001 and FCD (Forest Canopy Density) mapper were used to perform the spatial .elation of canopy density change. ILWIS (Integrated Land and Water Information System) which is GIS software and compatible with remote sensing data was used to execute analysis and visualize the results. Study found that influence of distance to suburb and river had statistically significance influenced in canopy change. Though road also influenced canopy density much but didn't show a statistical relation. It can be concluded from this research that understanding of spatial relation of factors respect with canopy change is quite complex phenomena unless detail analysis of surrounding environment. Hence, it is better to carry out comprehensive analysis with other additional factors such as biophysical, anthropogenic, social, and institutional factors for proper approach of their effect on canopy change.

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The Root from Heracleum moellendorffii Exerts Anti-Inflammatory Activity via the Inhibition of NF-κB and MAPK Signaling Activation in LPS-Stimulated RAW264.7 Cells

  • Park, Su Bin;Kim, Ha Na;Kim, Jeong Dong;Park, Gwang Hun;Son, Ho-Jun;Eo, Hyun Ji;Song, Jeong Ho;Jeong, Hyung Jin;Jeong, Jin Boo
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2018.10a
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    • pp.96-96
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    • 2018
  • Although the roots of Heracleum moellendorffii (HM-R) have been long treated for inflammatory human diseases, scientific evidence for the anti-inflammatory activity of HM-R is not sufficient. In this study, we investigated anti-inflammatory activity and mechanism of action of HM-R in LPS-stimulated RAW264.7 cells. HM-R blocked LPS-induced NO and PGE2 production, but not HM-L. HM-R inhibited LPS-induced overexpression of iNOS, COX-2, $IL-1{\beta}$ and IL-6 in RAW264.7 cells. HM-R inhibited LPS-induced $NF-{\kappa}B$ signaling activation through blocking $I{\kappa}B-{\alpha}$ degradation and p65 nuclear accumulation. In addition, HM-R inhibited MAPK signaling activation by attenuating the phosphorylation of ERK1/2, p38 and JNK. Furthermore, HM-R inhibited attenuated LPS-mediated overexpression of the osteoclast-specific factors such as NFATc1, cathepsin K, MCP-1 and TRAP. These results indicate that HM-R may exert anti-inflammatory activity by inhibiting $NF-{\kappa}B$ and MAPK signaling activation. From these findings, HM-R has potential to be a candidate for the development of chemopreventive or therapeutic agents for the inflammation and inflammatory diseases.

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Estimation of Above-Ground Biomass of a Tropical Forest in Northern Borneo Using High-resolution Satellite Image

  • Phua, Mui-How;Ling, Zia-Yiing;Wong, Wilson;Korom, Alexius;Ahmad, Berhaman;Besar, Normah A.;Tsuyuki, Satoshi;Ioki, Keiko;Hoshimoto, Keigo;Hirata, Yasumasa;Saito, Hideki;Takao, Gen
    • Journal of Forest and Environmental Science
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    • v.30 no.2
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    • pp.233-242
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    • 2014
  • Estimating above-ground biomass is important in establishing an applicable methodology of Measurement, Reporting and Verification (MRV) System for Reducing Emissions from Deforestation and Forest Degradation-Plus (REDD+). We developed an estimation model of diameter at breast height (DBH) from IKONOS-2 image that led to above-ground biomass estimation (AGB). The IKONOS image was preprocessed with dark object subtraction and topographic effect correction prior to watershed segmentation for tree crown delineation. Compared to the field observation, the overall segmentation accuracy was 64%. Crown detection percent had a strong negative correlation to tree density. In addition, satellite-based crown area had the highest correlation with the field measured DBH. We then developed the DBH allometric model that explained 74% of the data variance. In average, the estimated DBH was very similar to the measured DBH as well as for AGB. Overall, this method can potentially be applied to estimate AGB over a relatively large and remote tropical forest in Northern Borneo.

Tree Diversity, Distribution and Population Structure of a Riparian Forest from Certain Zones along the Dikhu River in Nagaland, India

  • Leishangthem, Devlin;Singh, Maibam Romeo
    • Journal of Forest and Environmental Science
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    • v.34 no.1
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    • pp.31-45
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    • 2018
  • At present the biodiversity of the riparian forest is under threat due to various anthropogenic pressures. Hence study was conducted along the three unprotected zones of riparian forest in Dikhu river, Nagaland, north-east India in order to compared the diversity, distribution and population structure of riparian trees. In each zone $100{\times}100m^2$ plot were marked and subdivided into 20 plots of $10{\times}10m^2$. 10 plots on each side of the river were taken randomly covering 0.02 ha. Only tree with dbh ${\geq}10cm$ and dbh above 1.5 m above ground level were recorded as individual species. A total of 29 tree species belonging to 18 families were recorded from the three zones of the river. Tree species richness was highest at the middle zone (19) followed by upper (14) and lower zone (7). The most abundant species and family recorded at upper, middle and lower zones were Melia azaderach of Euphorbiaceae ($380\;stems\;ha^{-1}$), Terminalia chebula of Euphorbiaceae ($432.5\;stems\;ha^{-1}$) and Duabanga grandiflora of Lythraceae ($365\;stems\;ha^{-1}$) respectively. The ranges of diversity indices observed in the three zones were: Shannon-Wiener index (1.25-0.73), Simpson diversity index (0.42-0.93), Evenness index (0.47-0.37) and Index of co-dominance (0.75-0.94). Rest of other indices were also estimated and compared. Distribution of trees shows the contagious pattern common in the upper and middle zones and regular in the lower zone. The girth size class analysis demonstrated that the riparian forest is in less mature succession stage. This study emphasize the need for management and conservation of riparian forest by developing policy to declare the riparian zone as protected area to prevent further degradation and loss of biodiversity from these unregulated zones along the river.

Development of Innovative Technologies for Enhancing Low Flow Discharge and Reducing Turbid Material from Overcrowded Forest Plantations by Intensive Thinning in Japan

  • Otsuki, Kyoichi;Kasahara, Tamao;Onda, Yuichi
    • Proceedings of the Korea Water Resources Association Conference
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    • 2012.05a
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    • pp.18-18
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    • 2012
  • In Japan, about 67% of the land is covered by forests and about 41% of them consist of plantations. About 35% of the plantations consist of old-aged plantations of older than 50 yearsand the percentage is projected to 67% in ten years' time. Although the trees of these plantations are supposed to be cut for timber production, most of them remain unmanaged and thus overcrowded mainly due to declining domestic forest industry. Since the forests are mostly located in headwater watershed, there are growing concerns about the degradation of water resources by these unmanaged plantations. To understand the ecohydrological processes in these plantations and examine the effect of intensive 50-60 % thinning to increase infiltration rate and reduce overland flow and soil erosion by recovering understory vegetation, the JST-CREST project "Development of Innovative Technologies for Increasing in Watershed Runoff and Improving River Environment by the Management Practice of Devastated Forest Plantation (Representative: Yuichi Onda)" has been launched since 2009. The ultimate objective of this project is to provide potential scenario to enhance low flow discharge in drought period and reduce turbid material in high flow period. We have been conductingintensive field observation campaign in five research sites across Japan. In Fukuoka site, integrated ecohydrological observations have been conductedin two contrastive watersheds since 2010. Intensive 50% thinning was conducted from January to April 2012 and comparative studies of ecohydrological processes before and after thinning have been started. The interim results from all the sites of this project will be presented in the 3rd International Congress for Forest and Water in a Changing Environment held in Fukuoka during 18-20 September, 2012 (http://www.forest.kyushu-u.ac.jp/~ecohydrol/3ForestWater/index.html).

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A Study on Damage Factors and Causes of Natural Forest in Regional Ecological Network at Chungnam Province (충남 광역생태네트워크 자연녹지의 훼손 인자 및 원인에 관한 연구)

  • Lee, Jong-Mun;Cho, Yong-Hyeon;Kim, Kwang Dong;Lee, Minwoo;Kim, Jinki;Choi, Jung-Kwon;Kim, Won-Tae;Yun, Chung-Weon;Kang, Hee-Kyoung
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.18 no.6
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    • pp.97-110
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    • 2015
  • This study aimed to classify damaged lands, to find what are the damage factors affecting the studied area, and to present a prescription in order to provide some benefit for the restoration of Regional Ecological Network at Chungnam province. Finally we classified damaged lands from 1st to 4th damaged lands according to relative intensity of damage. The main damage factors for the First Damage Lands were humus horizon, soil hardness and plant species richness. In the Second Damage Lands, those were soil hardness, plant species richness, number of plants and dominant plant species. In the Third Damage Lands, those were humus horizon, soil hardness, plant species richness, number of plants and dominant plant species. In the Fourth Damage Lands, those were humus horizon, organic matter, soil hardness, EC, T-N content, plant species richness, number of plants and dominant plant species. In every cases, the damage of soil and vegetation was originated due to development carried out by human being. The changes in soil condition were not big enough for it to affect plant growth, however, degradation of vegetation was still severe.

Study on the Hydrolysis Kinetics of Xylan on Different Acid Catalysts (다양한 산 촉매에서 자이란 가수분해 특성)

  • Na, Byeong-Il;Lee, Jae-Won
    • Korean Chemical Engineering Research
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    • v.52 no.2
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    • pp.226-232
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    • 2014
  • In this study, we investigated kinetic model for the acid-catalyzed xylan hydrolysis at temperature $120{\sim}150^{\circ}C$. Also, we analyzed the kinetic parameters for xylose production and furfural decomposition. The hydrolysis of xylan and the degradation of xylose were promoted by high reaction temperature and acid concentration. The optimal hydrolysis condition for the highest reaction rate constants ($k_1$) was different depending on the acid catalysts. Among sulfuric, oxalic and maleic acid, the xylan reaction rate constants ($k_1$) to xylose had the highest value of $0.0241min^{-1}$ when 100 mM sulfuric acid was used at $120^{\circ}C$. However, sulfuric acid induced more xylose degradation compared to oxalic and maleic acid hydrolysis. The activation energy for xylan degradation was the highest when sulfuric acid was used.