• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.1
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• pp.77-88
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• 2010

In order to ensure good animal health and performance, it is essential to produce forages with high feeding value and good hygienic quality. However, huge amounts of forages consumed by ruminants are contaminated with mold prior to harvest or during storage as hay, straw or silage. These mold can grow in forages only when nutrients are available, correct temperature exist, oxygen is present, and unbound water is available. Fungal 'species can be divided into two groups: field fungi and storage fungi. Field fungi invade the forages while the crop is still in the field, require high moisture conditions, and are such as species of Fusarium, Alternaria, Clodosporium, Diplodia, Gibberrella and Helminthosporium. Storage fungi invade forages during storage and need less moisture than field fungi. These such as species of Aspergillus and Penicillium usually do not occur any problem before harvest. Mold growth can spoil the nutritional aspects of the forages and also results in secondary metabolites that are highly toxic to animal, humans and plants. Moldy feeds are less palatable and may reduce dry matter intake. This, in turn, leads to a reduction of nutrition intake, reducing weight gains or milk production. Performance losses of 5 to 10 percent are typical with moldy feeds. Mycotoxins are toxic substances produced by fungi (molds) growing on crops in the field or storages. While greater than 400 mycotoxins have been chemically identified, the biological or veterinary medical impact of only several mycotoxins is known. Mycotoxins have attracted considerable attention as potential causes for poor performance and health disorders in domestic livestock. They can be carcinogenic, hepatotoxic, hematotoxic, immunosuppressive, estrogenic, or mutagenic. So, feeding moldy forages has adverse effects on animal health and milk consumers. Also, this author reported that rice straw hay was contaminated mycotoxigenic fungi such as Penicillium roqueforti and Fusarium culmorum in Korea. Therefore, it is an urgent need to develop an improved post harvest storage method to reduce nutrient loss and mycotoxin contamination of forages, which will have a positive impact on human health.

• The Korean Journal of Pesticide Science
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• v.6 no.4
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• pp.271-278
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• 2002

Methanol extracts from 420 samples of 173 plant species in 58 families were tested at 5000 ppm for their insecticidal and acaricidal activities against five economically important arthropod pests by spray method. The responses varied with arthropod pest species, plant species and plant tissue sampled. In a test with Nilaparvata lugens Stal, extracts from Zanthoxylum piperitum barks, Chamaecyparis obtusa leaf and Quercus salicina leaf showed potent insecticidal activity. With Plutella xylostella L., potent larvicidal activity was observed from extracts of Platycarya strobilacea wood, Meliosma myriantha barks, Sophora japonica leaf, Zanthoxylum piperitum barks, and Pinus thunbergii wood. Methanol extracts of Sophora japonica leaf and Zanthoxylum piperitum barks showed high insecticidal activity against Spodoptera litura. In a test with Tetranychus urticae Koch, extract from Carpinus coreana leaf, Firmiana simplex barks, Elaeagnus macrophylla leaf, Aralia elata leaf, Comus controversa barks and Chamaecyparis obtusa leaf exhibited strong acaricidal activity. As a naturally occurring pest control agent, Zanthoxylum piperitum barks could be useful as new insecticidal and acaricidal products against various arthropod pests.

• Journal of the Korean Wood Science and Technology
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• v.35 no.6
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• pp.13-22
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• 2007

This study was carried out to scrutinize possibility of manufacturing pitch pine (Pinus rigida) glued laminated timber in order to add values of pitch pine trees. Also, it was investigated to improve bending performance of pitch pine glulam. Pitch pine was imported as one of major plantation species in Korean peninsula. Machine stress rated grades of pitch pine lumber mostly ranged between E7 and E9. which grades were more or less inferior to producing high quality glulam. However, the adhesive properties between pitch pine and pitch pine, and between pitch pine and Japanese larch (Larix kaempferi Carr.), such as shear bond strength, wood failure rate and de-lamination rate of bonded layer submerged in cold and boiling water, were higher than Korean Standard criteria. These properties are essential for manufacturing glulam with single species or multiple species. The modulus of rupture (MOR) of pitch pine glulam exceeded the criterion of Korean Standard for glulam strength grade but modulus of elasticity (MOE) was lower than the criterion. On the other hand, the bending performances (MOR and MOE) were improved 20 percent by mixing with Japanese larch laminar. It is effective to arrange higher quality Japanese larch laminar at the outer layer of glulam for improving bending performances. In conclusion, it is possible to use low quality pitch pine as laminar of structural glulam for adding values of pitch pine.

• Korean Journal of Environment and Ecology
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• v.23 no.1
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• pp.56-65
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• 2009

In Korea, Red pine(Pinus densiflora) stands at a very important place, historically, culturally, and emotionally and it is one of the tree species that can produce domestic timber as forest resources economically. The growing space for Red pine forest in Korea is gradually reducing while the space for deciduous tree forests including oak series is gradually increasing. Thus, it is required that the research work should be done on renewal for pine forest retention and its related forest management practices. This research aims at developing stable, sustainable management forests and inducing nature renewal by grasping growth environment and succession process through the pattern of stand and structure analysis of the red pine(Pinus densiflora) for central region. The pine forests in central region were classified into four communities, such as Acer pseudo-sibolianum, Quercus acutissima, Lindera erythrocarpa, and Pinus densiflora and they are showing different characteristics by pattern according to their growing district. There appeared a lot of red pines in the upper layer, but there existed high weight of broad-leaved forest tree species, such as oak series in the middle layer and the appearance of the red pine was meager in the lower layer. Therefore, it appears that the red pine has a high influential ecological strength in terms of correlativity; however, if the red pine in tree layer is dead by aging in nature state with the lapse of time, it is considered that oak species, such as Quercus mongolica, Quercus variabilis, and Quercus serrata will be dominant below sub-tree layer. In addition, there appear differences in characteristics and growth pattern of the red pine forest depending on stand pattern, so it is considered that a differential application method should be employed in the pine forest management.

• Journal of Environmental Policy
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• v.7 no.4
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• pp.75-103
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• 2008

It is widely recognized that destruction of the eco-system with the counter-effect from the rapid industrialization threatens the life of human species. Furthermore, the extinction of some wild species keeps sending a warning message on the threat to human lives in the sense that both the human and wild lives have coexisted for a long time before the industrialization. Therefore, this study will shed a light on the importance of a natural ecology protection, focusing on wild-life conservation. This will provide an opportunity to consider the economic value of biodiversity through conservation of diverse wild lives and a natural ecology. Also, the irreversible damage to natural resources and extinction of certain species represent the urgency of this issue. This paper will perform a theoretical examination on the concept of wild plants and animals, an analysis of factors influencing their survivals, as well as the theory of natural ecology protections. This also examine the problems arising out of current domestic legislation of a natural ecology protection, comparing it with case studies of foreign countries. Through these analysis, this paper will seek for a maintenance of the currently enforcing natural ecology protection law to overcome its limits and will ultimately find alternatives to current system.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.1
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• pp.131-135
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• 2007

Various Phellinus species (Hymenochaetaceae) including P. linteus, P. baumii, P. pini, and P. igniarius of domestic and foreign products, were examined by gas chromatography to validate their composition of crude polysaccharides. The crude polysaccharide fraction, which is known to be one of the physiologically active fractions, were prepared by a cold ethanol precipitation method and the yield of the crude polysaccharide fractions of P. linteus, P. baumii, P. pini, and P. igniarius were 15.0%, 5.1%, 6.3% and 5.7%, respectively. The total monosaccharide amount of the crude polysaccharide fraction of P. linteus was 148.713 mg/g (dry weight of mushroom) while those of P. baumii, P. pini and P. igniarius were 29.022 mg/g, 29.222 mg/g and 1.546 mg/g, respectively. Although the major monosaccharide of all Phellinus mushrooms was glucose, there were remarkable differences in the absolute quantity of each monosaccharide. P. linteus included plenty of monosaccharides except mannose and ribose in comparison with P. baumii and P. pini. The absolute quantities of monosaccharides of P. baumii and P. pini were nearly similar except arabinose. The total monosaccharides of P. igniarius were minimal, but the portions of galactose and mannose in P. igniarius were greater than in the other species.

• Ecology and Resilient Infrastructure
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• v.8 no.2
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• pp.97-111
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• 2021

This study was conducted to develop a habitat type classification system and its map based on the ecological characteristics of species, spatial type, vegetation, topography, and geological conditions preferred by species. To evaluate the relationships between species and their habitats in Korean national parks, we prepared a classification standard table for systematic classification of habitat types. This classification system divides habitats into 6 low-level and 59 mid-level ecological classes based on habitat structure. The mid-level system divided forest ecosystems into 20 subtypes, stream and wetland ecosystems into 8 types, coastal ecosystems into 7 types, arable land into 6 types, development land into 9 types, and 1 type of marine ecosystem. A habitat classification map was drawn utilizing square images, detailed vegetation maps, and forest stand maps, based on the above habitat classification system, and it covered 1,461 plots spanning 21 national parks. The habitat classification system and survey protocol, which consider domestic habitat conditions, should be further developed and applied to habitat assessment, to enhance the utility of this study.

• Journal of Korean Society of Forest Science
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• v.111 no.1
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• pp.36-49
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• 2022

The purpose of this study was to analyze domestic research trends related to the Baekdudaegan Mountains in the last two decades. In total, 551 academic papers and keyword data related to the Baekdudaegan Mountains were collected using the "Research and Information Service Section" and analyzed using "big data" analysis programs, such as Textom and UCINET. Papers related to the Baekdudaegan Mountains were published in 177 academic journals, and 229 papers (41.6% of all published papers) were published between 2011 and 2015. According to word frequency data (N-gram analyses), the major research topic over the past 20 years was "species diversity." According to CONCOR analysis results, the main research could be divided into 15 areas, the most important of which was "species diversity," followed by "vegetation restoration and management," and "culture." Ecological research comprised 12 groups with a frequency of 78.8%; humanities and social research comprised 2 groups with a frequency of 15.6%. Overall, our study of research areas and quantitative data analyses provides valuable information that could help establish policy formulation.

• Journal of Korean Society of Forest Science
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• v.112 no.4
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• pp.554-560
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• 2023

To prevent illegal timber distribution, DNA markers have been used to identify the species and origin. However, extracting high-quality DNA from timber is difficult because of its physical and chemical properties. In this study, we investigated whether the age of timber tissue influences the yield of DNA extraction and the success rate of polymerase chain reaction (PCR) to understand the relationship between the establishment time of the wood annual ring and the extracted DNA concentration (ng/μl), purity (A260/A280), and PCR success rate (%) from pinewood, a major Korean domestic species. According to the results, it was observed that as the distance from the cambium increased, indicating that the tissue was older, the concentration and purity of the extracted DNA decreased significantly. For the trnM-trnV (285 bp) and rpoC1 (298 bp) regions, the PCR success rate was 100%. However, for the rbcL (1.3 kb) region, the PCR success rate was 66.67%. Moreover, PCR amplification of the rbcL region failed at all points older than 30 years. Thus, it is deduced that as time passes, along with the decay of timber cells, DNA is degraded, leading to a decrease in DNA concentration, purity, and PCR success rate. The results of this study are expected to be beneficial for future applications, such as the species identification of timber, providing valuable insights and potential utilization in this field.

• Korean Journal of Environmental Biology
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• v.42 no.1
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• pp.62-79
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• 2024

Garlic mustard (Alliaria petiolata) is a species that has devastated the United States and Canada. It is known to play a role in destroying the ecosystem. In this study, the domestic distribution of garlic mustard was confirmed and a detailed distribution map was created for the Samcheok region, where the largest population has been established in South Korea. This study investigated the growth environment, life cycle, and population dynamics of the species in the Samcheok region. Garlic mustard was found in a total of 301 locations in Samcheok, with a total distribution area of 2,957 square meters. Annual plants germinated in mid-April, overwintered in rosette form, underwent vegetative growth from April 10 to April 24 the following year, and flowered from April 24 to May 7. Individuals producing seeds began to die off from June. Both annual and biennial individuals showed a trend of increasing and then decreasing in number around April 27 (118 days). Garlic mustard grew well under favorable light conditions in early spring. They showed less growth on leaf litter, short distance from roads, lower altitude, deciduous broad-leaved forest of middle and lower parts of the slope and forest edge. Without proper control measures in the Samcheok region, it is likely to spread more rapidly in deciduous broad-leaved forests along hiking trails in the Galyasan Mountains. In particular, it is more likely to extend to oak community where light enters the site during flowering than to pine community where there is less light in the site.