• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.12 no.5 s.104
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• pp.80-86
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• 1991

임업에서 육림(育林)은 기르고자 하는 수종과 경쟁하는 잡초목과의 싸움이라고 할 수 있다. 대개 가치있는 수종은 초기생장이 느리고, 제거 대상이 되는 잡초나 관목및 활엽수의 맹아등은 초기 생장속도가 아주 빠르고 생존력이 강하기 때문에 방치하는 경우 조림목은 피압되어 고사하게 된다. 현재 여러가지 사회적인 여건에 의하여 인력작업이 어려운 시점에서 제초제의 활용은 이러한 문제를 해결할 수 있는 가장 효과적인 방법이라고 할 수 있다. 그러나 제초제의 사용은 세심한 주의가 필요하다. 제초제의 잘못 사용은 효율적인 작업성과를 얻지 못할 뿐만 아니라 오히려 기르고자 하는 나무를 손상할 수 있으며 대면적에 대한 과다한 사용은 산지의 황폐나 또는 자연생태계에 큰 영향을 줄수도 있다. 이러한 점에서 앞으로 제초제의 산지 적용에 대한 폭넓은 연구와 검토가 이루어져야 하겠다. 또한 여기서 소개하는 몇가지 제초제에 대하여도 사용할 때는 약제의 특성에 대한 충분한 지식을 가지고 대상지의 식생이나 입지조건에 대한 면밀한 조사가 이루어진 후에 사용하여야 할 것이다.

• The Korean Journal of Ecology
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• v.17 no.1
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• pp.49-58
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• 1994

To investigate the relationship between leaf growth of several woody plants and ait tempera ture in early growing season (from April to June) in deciduous forests, I surveyed the changes of leaf area (LA), leaf weight (LW) and specific leaf area (SLA) of 19 specles, in two areas Namhansansung (NA) and Taegwallyong (TA) area in which that the latitudes are similer ($37^{\circ}28'N$ at NA and $37^{\circ}27'N$ an TA), but annual mean-temperatures were different ($11.8^{\circ}C\;in\;NA, \;6.3^{\circ}C$ in TA) for two years, 1991 and 1992. In the same species, the plants of NA began to grow 10-25 days earlier than those of TA, but the latter grew faster than the former. On 10 June the values of LA and LW per leaf were similar in the two areas but the maximum values of SLA were higher in NA. In the same plant, the values of LA and LW were constant year by year, except for PYIOLUS leveilleana, Quercus mongolica, Symplocos chznensis for. pilosa and S t y a r ubussiu. In N A , the leaves be gan to grow during the first ten days of April, and eariler in 1992 than in 1991, and daily mean temperature (DMT) of the former from 27 March to 6 April were higher than those of thc latter. But the LA increased faster in 1991 than in 1992. and DMT from 10 April to 16 April were higher in 1991 than in 1992.

• Journal of Korean Society of Forest Science
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• v.31 no.1
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• pp.48-52
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• 1976

In order to investigate the effects of seed weight, size (length and thickness), and maturation period (early maturing seed or late maturing seed) on growth of first-year seedlings in Pinus koraiensis, pot cultivation experiment with seeds collected from Gangweon University Forest was carried out under relatively controlled environment condition. At the end of one growing season, not only fresh weight, length, diameter (at underside of cotyledon) and root length of seedlings, but also number and length of cotyledon were measured. Results are as follows; 1. Germination percentage is independent of weight and size of seeds, but it was influenced by maturation period, that is, late maturing seeds surpass early maturing one in germination percentage. 2. Germination percentage is affected by maturation period of seeds in 18.3% of contribution rate. 3. Each growth of first-year seedlings is influenced considerably by the differences of weight, length and thickness of seeds, that is, heavy and large seeds produce larger seedlings than do light and small seeds. Particularly, fresh weight, diameter, length of cotyledon are significantly affected by differences of seed weight and size (length and thickness) in 50-90% of contribution rate. 4. Differences of seed weight and thickness have a tendency to affect more on growth of first-year seedlings than do differences of seed length. 5. Seedlings from late maturing seeds are superior than those from early maturing one in fresh weight, diameter of seedlings and length of cotyledon, but it's influence is a little.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.3
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• pp.262-269
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• 1994

This study was conducted to clarify high yielding factors of F$_1$ hybrids in terms of the growth characteristics, canopy structure, nitrogen content and nitrogen profile in the canopy. Varieties used in this study were four hybrid rices showing different heterosis in grain yield and their parents. Varieties of Japonica were Reimei (maintainer), TP 681 and TP 1278(restorers), and F$_1$ (Reimei ms ${\times}$ TP 681, Reimei ms ${\times}$ TP 1278) hybrid rices. Those of Indica type were 1378 (maintainer), Milyang 46 and Suweon 287(restorers), and F$_1$ (1378 ms ${\times}$ Milyang 46, 1378 ms ${\times}$ Suweon 287) hybrid rices. High heterosis in F$_1$ hybrid rices were shown in panicles per hill and spikelets per panicle, being greatest in spikelets per panicle. Spikelets per square meter expressed even greater heterosis than those two yield components because of multiplicative effect of them. Heterosisof ripened concentration of leaf nitrogen and steeper gradient of leaf nitrogen in canopy strata but also better productive structure in favor of light interception seemed to have led to higher canopy photosynthesis of F$_1$ hybrids and subsequent higher partition of assimilates for leaf area expantion especially during vegetative growth stage. Higher dry matter production, resulting from these factors, during vegetative stage would have contributed to the production of greater number of spikelets per square meter, and consequently to higher grain yield in F$_1$ hybrids.

• Journal of Korean Society of Forest Science
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• v.109 no.3
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• pp.281-290
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• 2020

The purpose of this study was to determine the optimal planting density for Zelokva serrata plantations. The study sites were located in Gyeongsan (GS) and Sunchang (SC), Korea. One-year-old, bare-root seedlings were planted at densities of 3,000; 5,000; 7,000; and 10,000 trees ha^-1 at the end of March 2015. We measured the root collar diameter and height each September from 2015 to 2019, and then calculated the H/D ratio and stem volume. The root collar diameter and height increased with increased planting density, and the stem volume was significantly higher at 10,000 trees ha^-1 than those at the other planting densities. Planting density did not affect the survival rate or H/D ratio. The root collar diameter, height, and stem volume were higher in GS than those in SC five years after planting. This study highlights that early growth performance was improved at increased planting densities at both sites. This study suggests that the initial planting density of 10,000 trees ha^-1 is suitable to improve the early growth performance of Z. serrata plantations, and that the improved growth performance at higher planting densities may be a silvicultural characteristic of Z. serrata.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1998.10a
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• pp.151-155
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• 1998

본 실험은 무등산수박과 달고나수박으로 98년 4월 2일에 파종하여 4월 24일 토양과 펄라이트＋코코피트 혼합배지에 각각 정식하였다. 무등산수박과 달고나수박의 재배방법에 따른 생장결과를 보면 엽수는 달고나수박이 많은 반면 총엽면적은 무등산수박이 높게 나타났다. 생체중 및 건물중에 있어서도 달고나수박보다 무등산수박이 더 높게 나타났으며 토양재배보다 양액재배 수박이 더 월등한 생장차이를 나타내었다. 당도는 달고나 수박이 무등산수박보다 훨씬 더 높은 반면 과실무게는 무등산수박이 더 높게 나타났다. 엽병내 질소흡수량은 생육초기에는 26,000-30,000prm 정도이었고 수분후 33일에는 38,000-44,000ppm 정도로 상승하였다. 인산은 생육초기 4,000-8,800ppm 정도에서 수확기에 이르면 480-l,600ppm 정도로 감소하였다. 칼륨은 생육초기에 10,000-26,000ppm 정도였으나 수분기부터는 8,000-14,000ppm 범위로 흡수되었다. 칼슘의 흡수는 생육초기에는 앙액재배 수박이 52,000-5,700ppm 범위로 토양재배 수박의 2,700-3,900ppm 범위보다 약간 많은 것으로 나타났지만 생육이 진전됨에 따라 토양재배 수박의 흡수량이 양액재배 수박의 흡수량보다 많아지는 경향이었다. 마그네슘의 흡수는 생육초기에 토경에서 훨씬 더 용이하게 흡수되는 경향이었으나 수분기부터는 200-700ppm 범위로 일정하였다.

• Horticultural Science & Technology
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• v.18 no.4
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• pp.499-502
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• 2000

Five local cultivars of northern type garlics (Allium sativum L.) and one of southern type were collected, and their growth and developmental characteristics and productivity were investigated to select a well adaptable cultivar in Euiseong region. Local cultivars used in this experiment were 'Euiseong', 'Yeochun', 'Danyang', 'Jungsun', and 'Yongin' as northern type and 'Namdo' as southern one. The growth characteristic of local garlic cultivars were differed with their ecotypes and 'Namdo', a southern type cultivar, showed higher growth rate at the early growing stage than northern types. However, no clear differences were observed among northern types. Incidence of bolting was low in 'Jungsun' and 'Yongin', while high in 'Euiseong' and 'Yeochun'. In the case of incomplete bolting, however, an opposite trend was showed, thus, high in 'Jungsun' and low in 'Euiseong' and 'Yeochun'. Secondary growth was remarkably low in 'Euiseong'. Considering yield factors, 'Yeochun' seemed to be most promising northern type cultivar in Euiseong region, which showed highest bulb weight and largest cloves with high growth rate at the maximum growing stage. 'Danyang', 'Jungsun', and 'Yongin' seemed to have relatively low productivity in Euiseong region.

• Journal of Korean Society of Forest Science
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• v.87 no.1
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• pp.40-49
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• 1998

This study aimed to provide a strategy for selecting an adequate combination of growth intervals(i.e. times between age $T_1$ and age $T_2$) to be used to improve the reality of the growth equation through obtaining better precision of parameter estimates. Variety of growth functions were fitted to the data and one equation which best fitted the data was chosen for the analysis. A modified Schumacher projection equation, selected as a best equation, that included dummy variables representing locality as a predictor variable was fitted for basal area and height equations with nonoverlapping growth interval and all possible growth interval data sets of Douglas-fir(Pseudotsuga menziesii Mirb.Franco). The data were measured in all parts of the South Island of New Zealand. It was found that the precision of parameter estimates was increased in both basal area and height equations by using data set which contained a range of measurement intervals from short to long term.

• Korean Journal of Agricultural and Forest Meteorology
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• v.15 no.4
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• pp.210-218
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• 2013

The sea breeze shows different characteristics compared to land breeze, such as high wind speed and more rapider shift period. One of the major factors affecting plant early growth is wind speed. In the early growth stage, tree growth-rates rise with decreasing wind speed. Thus, the study was performed to identify wind break effects on wind characteristics and tree growth. The wind break used in this study was about 130 meters length and 3 meters height, made up with poly-ethylene (with 40% openness). We installed one vane and fifteen anemographs at three different heights (1, 2 and 3 meters) on the inner and outer wind break areas. The wind characteristic and plant growth data were collected from Jun. 2011 to Oct. over 2012. The wind rose of the Saemangum seawall area presented the north (21.5%) and it was followed by north-west (18.1%), east (14.9%) and north-east (13.7%) and the remainder with other directions. Wind speeds at height were different. The tree height was 159.6 cm at inside and 129.6 cm at outside. The diameter at root-collar was 36.9 mm at inside and 32.6 mm at outside from wind break.

• Korean Journal of Plant Resources
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• v.19 no.4
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• pp.530-536
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• 2006

Hardwood cutting propagation and early growth characteristics were investigated in order to develop the method of cutting propagation and to find out growth characteristics in the low altitude for in situ and ex situ conservation of Empetrum nigrum var. japonicum K. Koch, which is typical arctic alpine plants on Mt. Halla. The growth of roots and shoots was different depending on hormone concentrations or soil conditions. The survival rate, rooting rate, root growth, number of root and shoot growth increased with treatment of 100 mg/l or 500 mg/l NAA. Consequently, optimum condition of hardwood cutting was at treatment with 100 mg/l or 500 mg/l NAA. When plantlets from hardwood cuttings were exposed to the field condition, after 7 months survival rate was 73.3% without shading while $91.1{\sim}94.4%$ at shading conditions. In the green house, however, survival rate of plantlets were $95.6{\sim}97.8%$ without shading. The growth of plantlets was different depending on sites and shading conditions. Particularly, the best growth was obtained when the plantlets were grown in shading conditions. It indicates that relative humidity and light intensity are correlated with the growth in the low altitude area.