• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.755-763
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• 2010

Fine sediment loadings from agricultural watersheds have led to habitat degradation in Lake Takkobu, northern Japan. Fifteen lake sediment core samples were obtained and analyzed to develop a chronology using physical sediment characters, $^{137}Cs$, and tephra. The reconstructed sedimentation rates over the past ca 300 years suggested that sedimentation rates increased drastically after land use development. With a natural sedimentation rate of 0.1-1.1 mm $year^{-1}$ until 1898, lake sedimentation accelerated to 0.6-12.8 mm $year^{-1}$ after 1898. The sedimentation rates after land use change, such as forestry, river engineering works, and agricultural development, were about 6-12 times higher than that under natural conditions, leading to accelerated lake shallowing over the last ca 100 years. Sedimentation rates between 1898 and 1963 differed with location in the lake because of spatial variation in the sediment flux from the contributing rivers and their watersheds. The sedimentation rate in the southern zone between 1898 and 1963 was significantly higher than that in the middle and northern zones, reflecting active sediment production associated with forestry for charcoal production and canal construction for transportation in the southern watersheds and wetlands. The sedimentation rate after 1963 did not vary among the three zones, because decreasing sedimentation was found in most of the southern sites whereas an increasing trend was observed in the middle and northern sites. This result can be explained by shallowing of lake-bottom morphology with sedimentation and the resultant reduction of sediment retention capacity in the southern zone. Moreover, the sedimentation rate at sampling sites close to river mouths increased by 5-32 times compared with natural rates before 1898. The Kushiro River, into which Lake Takkobu drains under regular flow conditions, further contributed to an increased sedimentation rate, because water from the Kushiro River flows back into Lake Takkobu during floods.

• Korean Journal of Environmental Biology
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• v.37 no.3
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• pp.229-248
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• 2019

This study was carried out to investigate the flora of Mt. Jaamsan on the Gyeongsang supergroup, Korea. From the results of eight field surveys from March to October 2017, we have identified 530 total taxa, representing 483 species, eight subspecies, 35 varieties, two forms, and two hybrids, which were placed in 325 genera and 110 families. The plant formation of Mt. Jaamsan is the deciduous broad-leaved and conifer mixed forests, which are the common ones in the middle part of the Korean Peninsula. Most of the mountain is covered with young secondary forest, which is mainly composed of Quercus spp., and Pinus. Out of these 530 taxa, 12 are endemic to Korea, 17 taxa are listed on the Korean Red List of threatened species, 65 are floristic target species, and 55 are invasive alien species. The percentage of naturalized index(NI) and urbanization index (UI) were 10.4% and 17.2%, respectively. Mt. Jaamsan has a high plant diversity, including endemic and rare species, which consist of geomorphological landscapes. We considered that the composition and distribution of species are affected by the different environmental factors according to the sedimentary rocks, drying ridges, valleys, and streams. Together with the rocks and soils were the substrate type that play a major role in providing the unique habitats for sun plants in the area.

• Journal of Korean Society of Forest Science
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• v.28 no.1
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• pp.67-96
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• 1975

The serious consequences of the roadside erosion and its impact on sedimentation and deterioration of roadside landscape continue to be documented in Koreas. An analysis on the landscape conservation treatments was made through the field survey for the 8 radial roadsides around Seoul area. This was performed to identify and evaluate the present restoration measures, and to establish the practical standard measures for the landscape conservation treatments on the cut-and banking roadside slopes.

• Journal of Korean Society of Forest Science
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• v.80 no.4
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• pp.369-378
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• 1991

Major statutory nature protection areas include Nature Parks, Nature Reserves. Nature Ecological System Protected Areas. Biosphere Reserves, Nature Protected Forests, Wildlife Sanctuaries, and Protection Forests with total area of 1,124,000 ha. These protected areas cover almost 18% of the forested area. The number of visitors of NPs reached over 33 million per year with sharp increasing rate over the years. To protect the deteriorated hiking trails and camp grounds caused by overuse, two management policies have been implemented : cooking prohibition and natural rest rotation system. While prohibition of cooking is based on the fact that most of the solid wastes in nature parks are leftovers of cooking, natural rest rotation system is mainly for rehabilitation of deteriorated areas by natural processes. The system has closed 47 trails(in 27 mountains) throughout the country since January 1991, which is scheduled to continue 3 years. Due to the lack of accumulated scientific knowledge on how, when and where to close, application of the system leaves much to be desired. This paper discusses the current efforts to protect the natural resources for recreational use and suggests future directions for an effective policy implementation.

• Korean Journal of Environment and Ecology
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• v.25 no.5
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• pp.710-716
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• 2011

The growth characteristics and the several component content of leaves in one year old tetraploid of Robinia pseudoacacia introduced at five site planted respectively were surveyed in Sangwon area Pyongyang, and the expand plant possibility and the leaves harvested as feed additive use of possibility in Democratic People's Republic of Korea was discussed in comparison with tetraploid of R. pseudoacacia of Yanqing area. The results were as follows (1) the length and stump diameter of annual sprouting stems at Sangwon area were smaller 50% than the tetraploiod of R. pseudoacacia stems that Yanqing area; (2) the length of sprouting stems in slope sites of Eastern (E), Western(W) and Southern(S) at Sangwon were higher 23~30% than the length that Northern slope site(N), and the diameters of sprouting stem in the slope of Eastern(E) and Southern(S) were higher 14~23% than the slope sites of Northern(N) and Western(W); (3) crude protein contents and ash contents of leaves at Sangwon were higher 40% general R. pseudoacacia and similar to the leaves that Yanqing area.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.21 no.3
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• pp.103-111
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• 2016

Seasonal dynamics of kelp forest-forming algae, Ecklonia cava population formed following the large-scale disturbance by Typhoon 'Bolaven' in August 2012 were investigated in Jeju Island, Korea. Morphological characteristics, recruits density, mortality rate, total density and biomass were monitored bimonthly from June 2013 to June 2015. Total and longest blade lengths, and individual weight of E. cava showed distinct seasonal trends. Stipe length increased from winter to spring, but did not show increase or reduced from summer to autumn. This indicates that morphological characteristics of E. cava are mainly affected by the change of blades. The optimal temperature for E. cava growth was about $15-18^{\circ}C$ during winter to spring while the growths were inhibited at the water temperature above $20^{\circ}C$ during summer. E. cava exhibited very low recruitment during spring-summer. However, high recruitment was observed on April 2015 when canopy cover was very low due to low density. This indicates that recruitment of E. cava was controlled not by seasonal effects but by physical factors such as canopy and space. The mortality rate of juvenile plants was highest due to their unstable settlement. By June 2015, 34 months after the disturbances, E. cava was almost recovered to the pre-disturbance population size structure. These results suggest that recovery of kelp forest following the large-scale disturbance requires a considerable period of time (more than three years). This study should provide valuable ecological information on management, restoration and protection of kelp species.

• FLOWER RESEARCH JOURNAL
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• v.18 no.1
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• pp.29-32
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• 2010

This study was conducted to determine the effects of cutting position, media, and auxin on rooting of Artemisia keiskeana cuttings. In the cutting positions, the cutting of middle and basal positions had a better growth in the both upper and lower part than the cutting of the top position. Especially, the cutting of the middle position showed the highest rooting rate, at 68.3%. In the media, peatmoss showed the latest date on the rooting initiation. Also, the growth, survival rate and rooting rate of the upper part and lower part were low. However, the cutting in vermiculate showed the fastest date on the rooting initiation, and had a significant effect on the growth of the upper part and lower part, showing the highest rooting rate and survival rate in all tested media. When cuttings were treated by auxin, the rooting rate and growth of cuttings were higher than the control. The control showed the lowest rooting rate, at 41%, while, the auxin treatment showed the highest, rate over 80%. Whereas when treated by NAA, the lower part of cuttings had a better growth than these treated by IBA. Also, the higher the concentration of auxin was, the higher the rooting rate and growth rate of Artemisia keiskeana cuttings were.

• Journal of Climate Change Research
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• v.9 no.4
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• pp.303-312
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• 2018

In Ethiopia, climate change and deforestation are major issues hindering sustainable development. Local Ethiopian communities commonly perceive an increase in temperature and a decrease in rainfall. Meteorological data shows that rainfall has declined in southern Ethiopia, and spring droughts have occurred more frequently during the last 10-15 years. The frequently occurring droughts have seriously affected the agriculture-dominated Ethiopian economy. Forests can play an important role in coping with climate change. However, deforestation is alarmingly high in Ethiopia, and this is attributed mainly to agricultural expansion and fuel wood extraction. Deforestation has led to a decrease in various benefits from forest ecosystem services, and increased ecological and environmental problems including loss of biodiversity. To resolve the issues effectively, it is crucial to enhance climate change resilience through reforestation and various international collaborations are urgently needed. To continue collaboration activities for resolving these issues, it is first necessary to address fundamental questions on the nature of collaboration: does collaboration aim for a support-benefit or a mutual benefit situation; dividing the workload or sharing the workload; an advanced technology or an appropriate technology; and short-term and intensive or long-term and extensive?. Potential collaboration activities were identified by sectors: in the governmental sector, advancing governmental structure and policy, enhancing international collaborations and negotiations, and capacity building for forest restoration and management; in the research and education sector, identifying and filling gaps in forestry and climate change education, capacity building for reforestation and climate change resilience research, and developing bioenergy and feed stocks; and in the business and industry sector, supporting conservation based forestry businesses and industries, while promoting collaboration with the research and education sectors. It is envisaged that international collaboration for enhancing climate change resilience through reforestation will provide a strong platform for resolving climate change and deforestation issues, and achieving sustainable development in Ethiopia.

• Journal of Environmental Impact Assessment
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• v.27 no.6
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• pp.521-547
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• 2018

To provide fundamental information to areas that lack data on the plant resources and the ecosystem, this study conducted a survey on the vascular plants in Mt. Jigisan in Hongseonggun. The vascular plants identified during the six-round field surveys were a total of 443 taxa: 96 families, 286 genera, 391 species, 7 subspecies, 40 varieties, 3 forms, and 2 hybrids. On floristic regional of Korea, Mt. Jigisan is deciduous broad-leaved and conifer-mixed forest which is south province of Korean peninsula. 4 taxa of Korean endemic plants such as Populus ${\times}$ tomentiglandulosa, Forsytsythia koreana, Forsytsythia ovate, and Iris rossii var. latifolia were collected. The vascular plants on the red list according to IUCN evaluation basis were found to be 6 taxa: Vulnerable (VU) species of Forsytsythia ovata, Least Conern (LC) species of Chionanthus retusus, Pseudoraphis ukishiba, and Cymbidium goeringii, and Not Evaluate (NE) species of Panax ginseng, and Fimbristylis verrucifera. The floristic regional indicator plants were found 27 taxa: 2 taxa of grade V, 3 taxa of grade IV, 6 taxa of grade III, 4 taxa of grade II, and 12 taxa of grade I. The specific distribution plants were found 27 taxa: 4 taxa of northern part of plants, 12 taxa of southern part of plants, 10 taxa of isolation distribution of plants, and 1 taxon of recently reported Viola betonicifolia var. albescens. The invasive alien plants were identified as 67 taxa. The naturalized index (NI) was 15.12%, and urbanization index (UI) was 20.9%, respectively.

• Korean Journal of Plant Taxonomy
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• v.50 no.4
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• pp.427-452
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• 2020

This study of vascular plants was conducted over a period of 33 days from March to October of 2018 in Byeonsanbando National Park, South Korea. Based on voucher specimens and photographs, 829 taxa in total were recorded, including 141 families, 458 genera, 748 species, 16 subspecies, 59 varieties, and 6 forma. Two endangered taxa were identified, Iris koreana Nakai and Saururus chinensis (Lour.) Baill. Five rare taxa were found, including Abeliophyllum distichum Nakai and Hypodematium glanduloso-pilosum (Tagawa) Ohwi. A total of 17 Korean endemic plants were investigated. Examples include Elsholtzia byeonsanensis M. Kim, Eranthis byunsanensis B. Y. Sun, and Lycoris flavescens M. Kim & S. T. Lee. Of floristic regional indicators (third to fifth degree), 52 taxa were identified. Naturalized plants were identified, which included 79 taxa, and 7 species of ecosystem disturbance plants, such as Ambrosia artemisiifolia L., Lactuca serriola L., and Solidago altissima L. were found. We recorded 39 taxa of the plants vulnerable to climate change.