• Journal of Korean Society of Forest Science
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• v.47 no.1
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• pp.37-43
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• 1980

This study have done to get the basical information that would be useful to make the ecological planting, selection of suitable species and weeding plan by the relation between the leading shoot elongation of several species and the climatic factors in the plantation. Sampling measurement have been done in the trial forest of Korean German Forest Management Project located in Joil-ri, Samnam-myeon and Ichcon-ri, Sangbug-myeon, Ulju-gun. The former is in lowland at 100m latidude and the latter is in highland of 600 m latitude. The elongation of leading shoot has been measured in the plantation with 10 days interval from the beginning of March in 1979 and the climatic datas has gotten in the weather station closed to the plantation. 1. The change of air temperature and rainfall in each measuring site is like Fig 1. and 2. The similar temperature in 600 m high latitude is coming about 10 days latter than 100 m latitude. 2. Genus pine as Pinus thunbergii, P. rigida, P. rigitaeda. P. koraiensis and P. taeda begin their leading shoot growth during March and air temperature in that time is around $6^{\circ}C$. In highland their beginning of leading shoot elongation has been found out 10 days latter than lowland. However Abies, Larix and Picea has shown to open their leading shoot during May, 40 days late in comparing with genus pine, and then temperature is making around $15^{\circ}C$. But Cryptomeria, Chamaecyparis and Cedrus deodora has shown their leading shoot opening in March in lowland and May in high land. The reason of late opening, specially in highland, seems to be the influence of winter frost. 3. Most of leading shoot elongation of genus pine has finished during the end 10 days of April and May under range of air temperate $10^{\circ}C$ and $20^{\circ}C$ and other species has finished most of their elongation during the end 10 days of May and June with air temperature range of $18^{\circ}C$ to $20^{\circ}C$. So the suitable season of weeding works show to genus pine in May and other species in June. 4. The leading shoot growth of genus pine has started earlier and closed earlier too than other species and, when over than $20^{\circ}C$ air temperature, their growth is decreasing quickly. Pices abies as well show to be decreased suddenly in over than $20^{\circ}C$ temperature. Other species show the similar trend when over than $22^{\circ}C$. This reason is considered as high temperature of summer season. 5. Annual elongated days of leading shoot of Picea abies is 50 days, Abies hollophylla 70 days, and more than 85 percentage of shoot growth of Pinus koraiensis and Larix leptolepsis are growing during 70 dys as well. The shoot growing days of Chamaecyparis, P. rigida, P. rigitaeda, P. taeda and P. shunbergii show longer period as over than 120 days. 6. The shoot elongation times per year of Abies and Picea has closed as one times and Genus pine is continuring their elongation more than two times. But Cryptomeria, Chamaecyparis, Cedrus deodora and Larix show one or two times elongation depending on the measuring site. The reason of continuring elongation more than than two times seems to be influenced by the temperature in summer season except the genetical reason. 7. Depending on the above results, as the high temperature in summer season could give the influence to grow the leading shoot in the plantation, this would be the considering point on the ecological planting and selection of the suitable species to the slope aspect. The elongation pattern by the season show to be the considering point too to decide the the weeding and fertilizer dressing time by the species.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1027-1034
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• 2011

In order to provide the basic information on the agricultural environment in Daegwallyeong Highland, the characters of weather, water, and soil quality were investigated. The meteorological characteristics was monitored by automatic weather system (AWS) at 17 sites. The quality of water for samples were collected monthly at 24 sites depending on landuse style. Soil samples were collected from a forest, grassland, and the major vegetable cultivation areas such as potato, carrot, Chinese cabbage, onion, head lettuce, and welsh onion field. The weather showed the mountain climate, and the average yearly temperature is $6.4^{\circ}C$, the average temperature in January is $-7.6^{\circ}C$ and the average temperature in July is $19.1^{\circ}C$, and the change of temperature on the districts of Daegwallyeong is severe. The yearly record of precipitation shows 1717.2 mm. The water quality of crop field was worse than forest or grassland in Daewallyeong highland. In 2005, annual T-N, T-P, SS distribution of Chinese cabbage field showed 7.4~11.3, 0.061~0.1, and $3.0{\sim}53.0mg\;L^{-1}$. The potato field showed 3.1~7.2, 0.019~0.056 and $0.5{\sim}3.0mg\;L^{-1}$, respectively. Being compared of water quality between potato field and chinese cabbage field, it showed that the water quality of Chinese cabbage field was worse than potato field. On farming, the soil of crop cultivation showed pH 5.6 to 6.8, $18.0{\sim}42.4g\;kg^{-1}$ of OM, $316{\sim}658mg\;kg^{-1}$ of Avail. $P_2O_5$. The content of cations showed $0.41{\sim}0.88cmol_c\;kg^{-1}$ of Exch. K, $3.73{\sim}7.07cmol_c\;kg^{-1}$ of Exch. Ca and $1.17{\sim}1.90cmol_c\;kg^{-1}$ of Exch. Mg.

• Journal of Biosystems Engineering
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• v.33 no.2
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• pp.106-114
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• 2008

This study was performed to analyze the distribution of air current speed, $CO_2$ concentration, and photosynthetic photon flux (PPF) in a closed transplants production system (CTPS) for producing quality transplants. And the effect of PPF on the growth of potato (Solanum tuberosum L. cv. Dejima) plug seedlings was analyzed. Uniformity of the air current speed in CTPS was improved by installing perforated floors in duct for air circulating and by adjusting of air flow rate of the fan connected to air conditioning unit used in this study, Measured $CO_2$ concentrations were measured $409{\pm}13$, $950{\pm}25$, and $1,550{\pm}35\;{\mu}mol{\cdot}mol^{-1}$ for setting values of 400, 950, and $1,550\;{\mu}mol{\cdot}mol^{-1}$, respectively. Uniformity of PPF by adding each one the single fluorescent lamp of 20 W at both ends of the single fluorescent lamps of 40 W was highly improved. While the average PPF measured under the twin fluorescent lamps of 55 W installed at regular intervals of 10 cm was decreased by increasing the vertical distance from the lighting sources, the ratio of average PPF measured at both ends to PPF measured in the center was 74-79%. Five levels ($100{\pm}9$, $150{\pm}14$, $200{\pm}17$, $250{\pm}24$ and $300{\pm}31{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) of PPF were provided to investigate the effect of PPF on plant height, fresh weight and dry weight of potato plug seedlings produced in CTPS. Plant height was decreased by increasing PPF. Maximum fresh weight and dry weight were shown under PPF of $250{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Thus PPF of $250\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ was enough to produce quality potato transplants under air temperature, photoperiod, and relative humidity of $20^{\circ}C$, 16/8 h, and 70%, respectively. It was concluded that quality indices such as plant height, fresh weight and dry weight could be improved by illuminating of adequate PPF from artificial lighting sources.

• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.495-501
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• 2011

Bacterial strains were isolated from forest soils of Halla mountain, Jeju island in Korea. The soil samples were collected at each altitude of 100m from 1,000 m above sea level. Total 398 strains were isolated and tested for their physiological characteristics of antagonistic and proteolytic activities, and auxin production. Among the isolates, 172 strains were selected as antifungal strains showing antagonistic activity against at least one of 8 plant fungal pathogens (Alternaria alternata, Botrytis cinerea, Collectotrichum acutatum, Fusarium oxysporum, Phytophthora capsici, Pythium ultimum and Sclerotinia sclerotiorum). In addition 203 strains for proteolytic activity and 26 strains for auxin production were characterized for further study. Je28-4 (Rhodococcus sp.) were showed 80% of control value against tomato gray mold in vivo. Thus, it is suggested that soil bacteria isolated from forest soils of Halla mountain can be important sources of bioactive compounds for improving plant growth or promising biocontrol agents.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.2
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• pp.29-36
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• 2013

The objective of the research was to describe the effect of straw mat cover and soil amendments on the reduction of runoff and non-point source load from steep sloped highland agricultural fields. Four $5{\times}30$ m plots on sandy loam soil with 28 % slope were prepared. Experimental treatments were bare (control), rice straw mat cover (3,000 kg/ha) (S), PAM (5 kg/ha)+Gypsum (1 ton/ha) (PG) and rice straw mat cover+PAM+Gypsum (SPG). A variety of lettuce was cultivated and runoff was monitored during a growing season in 2011. Natural monitoring was conducted to three times. Runoff rate of S, PG and SPG plots were significantly lower than those of control plot. Especially, the runoff rate is zero in SPG plot at a first rainfall events. The reduction rate of runoff from the S, PG and SPG plots was 30.8 %, 29.0 % and 81.8 % compared to control plots, respectively. The reduction rate of NPS pollution load of S, PG and SPG was ranged of 50~90 %, 30~70 % and 90~100 %, respectively. Yield of lettuce from S, PG and SPG plots was respectively 400 (567 kg/ha), 320 (453 kg/ha) and 760 (1,067 kg/ha) that of compared to control plots greater than that from control plots (140 kg/ha). We speculated that the experimental treated plots could hold more nutrients and moisture than the control and helped the crop grow healthier. When analyzing the above results, in terms of reduction of runoff and NPS pollution load and crop yields, SPG experimental treatment had the best effect. It was concluded that the use of rice straw mats cover and soil amendments on soil surface could not only reduce the NPS pollution loads in receiving waters but also help increase the crop yield.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.53-53
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• 2018

전라북도 동부권 지역은 중산악지형으로 표고 100~500m 산지가 69%, 500~1,000m가 26%로 이루어져 있어, 산채를 재배하기에 유리한 지리적 조건을 갖고 있다. 따라서 소비자의 수요가 높은 산채류의 재배 및 이용에 대한 농업인들의 기술개발이 요구되고 있다. 이에 전라북도 준고랭지역에서 재배하기 적합한 산채작목을 선발하고자 본 시험을 실시하였다. 시험은 표고 500m 전라북도 남원시 운봉읍 허브시험장에서 노지재배, 남원시 주천면 표고 530~540m, 진안군 주천면 표고 340~350m에 위치한 농가포장에서 임간재배를 실시하였다. 대상작물은 개미취(Aster tataricus), 갯기름나물(Peucedanum japonicum), 곤달비(Ligularia stenocephala), 눈개승마(Aruncus dioicus var. kamtschaticus), 단풍취(Ainsliaea acerifolia), 산마늘(Allium microdictyon), 섬쑥부쟁이(Aster glehnii), 어수리(Heracleum moellendorffii), 우산나물(Syneilesis palmata) 등 9종을 2016년 종묘를 정식하였다. 정식 2년차에 해당지역의 5월~9월 평균기온 및 조도 등 생육환경을 조사하고, 시험작물의 출현율, 생육특성, 수량 등을 조사하였다. 조사기간 동안의 평균기온은 노지가 $20.8^{\circ}C$, 남원임간은 $20.3^{\circ}C$, 진안임간은 $20.5^{\circ}C$이었으며, 평균조도는 노지가 37,362Lux, 남원임간은 7,816Lux, 진안임간은 25,316Lux이었다. 노지에서 출현율은 개미취, 갯기름나물, 눈개승마, 산마늘, 섬쑥부쟁이, 우산나물이, 임간에서는 개미취, 곤달미, 눈개승마, 단풍취, 산마늘, 어수리, 우산나물이 높았다. 생육특성은 노지에서 개미취, 갯기름나물, 눈개승마, 섬쑥부쟁이, 임간에서는 단풍취, 산마늘, 우산나물의 생육이 좋았다. 수량은 노지에서 개미취, 갯기름나물, 곤달비, 산마늘, 섬쑥부쟁이, 어수리가 높았으며, 남원임간에서는 곤달비, 단풍취, 우산나물, 어수리가, 진안임간에서는 개미취, 갯기름나물, 산마늘, 우산나물의 수량이 많았다. 이와 더불어 준고랭지에 적합한 산채류률 선발하기 위해서는 차후 재배 지역 및 방법의 차이에 따른 산채작물의 연차별 수량성과 경제성에 관한 연구가 이루어져야 할 것으로 여겨진다.

• Korean Journal of Agricultural and Forest Meteorology
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• v.19 no.3
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• pp.75-85
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• 2017

A method to estimate hourly temperature profiles on calm and clear nights was developed based on temporal changes of inversion height and strength. A meteorological temperature profiler (Model MTP5H, Kipp and Zonen) was installed on the rooftop of the Highland Agriculture Research Institute, located in Daegwallyeong-myeon, Pyeongchang-gun, Gangwon-do. The hourly vertical distribution of air temperature was measured up to 600 m at intervals of 50 m from May 2007 to March 2008. Temperature and relative humidity data loggers (HOBO U23 Pro v2, Onset Computer Corporation, USA) were installed in the Jungdae-ri Valley, located between Gurye-gun, Jeollanam-do and Gwangyang-si, Jeollanam-do. These loggers were used to archive measurements of weather data 1.5 m above the surface from October 3, 2014, to November 23, 2015. The inversion strength was determined using the difference between the temperature at the inversion height, which is the highest temperature in the profile, and the temperature at 100 m from the surface. Empirical equations for the changes of inversion height and strength were derived to express the development of temperature inversion on calm and clear nights. To estimate air temperature near the ground on a slope exposed to crops, the equation's parameters were modified using temperature distribution of the mountain slope obtained from the data loggers. Estimated hourly temperatures using the method were compared with observed temperatures at 19 weather sites located within three watersheds in the southern Jiri-mountain in 2015. The mean error (ME) and root mean square error (RMSE) of the hourly temperatures were $-0.69^{\circ}C$ and $1.61^{\circ}C$, respectively. Hourly temperatures were often underestimated from 2000 to 0100 LST the next day. When temperatures were estimated at 0600 LST using the existing model, ME and RMSE were $-0.86^{\circ}C$ and $1.72^{\circ}C$, respectively. The method proposed in this study resulted in a smaller error, e.g., ME of $-0.12^{\circ}C$ and RMSE of $1.34^{\circ}C$. The method could be improved further taking into account various weather conditions, which could reduce the estimation error.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.20
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• pp.9027-9031
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• 2014

Background: Helicobacter pylori (H. pylori) infection is an established cause of peptic ulcers and gastric cancer. The aim of this study was to identify H. pylori genotypes and to examine their associations with geographical regions and gastritis, peptic ulcers and gastric cancer in Laos. Materials and Methods: A total of 329 Lao dyspeptic patients who underwent gastroscopy at Mahosot Hospital, Vientiane, Laos during December 2010 - March 2012 were enrolled. Two biopsy specimens (one each from the antrum and corpus) were obtained for CLO testing and only CLO test-positive gastric tissue were used to extract DNA. PCR and sequencing were identified for variants of the cagA and vacA genotypes. Results: Some 119 Laos patients (36.2%) were found to be infected with H. pylori including 83 with gastritis, 13 with gastric ulcers (GU), 20 with duodenal ulcers (DU) and 3 with gastric cancer. cagA was detected in 99.2%. East-Asian-type cagA (62%) and vacA s1c (64.7%) were predominant genotypes in Laos. vacA s1c-m1b was significantly higher in GU than gastritis (53.8% vs. 24.1%; P-value=0.04) whereas vacA s1a-m2 was significantly higher in DU than gastritis (40.0% vs. 16.9%; P-value=0.03). East-Asian-type cagA and vacA s1c were significantly higher in highland than lowland Lao (100% vs. 55.8%; P-value=0.001 and 88.2% vs. 61.5%, P-value=0.03 respectively). Conclusions: H. pylori is a common infection in Laos, as in other countries in Southeast Asia. The cagA gene was demonstrated in nearly all Laos patients, cagA and vacA genotypes being possible important factors in explaining H. pylori infection and disease outcomes in Laos.