• Journal of Korean Society of Forest Science
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• v.58 no.1
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• pp.125-131
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• 1982

산지개간(山地開墾)에 의한 인공초지(人工草地) 조성(造成)은 급경사지(急傾斜地)이고 복잡(複雜)한 지형(地形)의 한국(韓國) 산악지(山岳地) 조건(條件)과 계절간(季節間)에 기후차(氣候差)가 심한 한국(韓國)의 기후상태(氣候狀態)로 보아 많은 문제점(問題點)이 있을 것이고, 이와 같은 지형(地形)과 기후조건(氣候條件)들 때문에 토지이용시(土地利用時) 신중(愼重)한 배려(配慮)가 요구(要求)된다. 산지황폐(山地荒廢)와 홍수피해(洪水被害) 등(等)이 국토관리상(國土管理上) 큰 문제점(問題點)으로 되어 왔고 금후(今後)에도 이 문제(問題) 해결(解決)은 토지경영(土地經營)에 있어 커다란 과제(課題)로 남아 있다. 또한 식량증산(食糧增産)을 위한 토지(土地)의 경제적(經濟的) 이용(利用)도 큰 과제(課題)의 하나임에는 틀림 없다. 이와 같이 토지이용상(土地利用上)에 서로 상충(相衝)되는 이들 과제(課題)를 해결하기 위하여 인공토지(人工土地) 조성(造成) 대책(對策)을 검토(檢討)한 바 임축인(林畜人)들이 상호(相互) 협동(協同)하여 이 과제(課題)의 기술(技術)을 개발(開發)시켜야 될 것으로 판단(判斷)이 된다. 국토보존(國土保存) 문제(問題)를 해결하고 동시에 인공초지(人工草地)의 문제점인 하고현상 식피밀도(植被密度)와 연년생장(年年生長)의 감소현상을 해결하기 위하여 상호보완적(相互補完的)인 생태적(生態的)인 방법(方法)이 도입(導入)되어야 할 것 같다. 이를 위해 삼림(森林)이 갖고 있는 토양침식방지(土壤浸蝕防止), 토양수분보지기능(土壤水分保持機能), 온도변화기능(温度變化機能), 공중온도(空中温度) 보지기능(保持機能), 방풍기능(防風機能)과 풍치기능(風致機能)을 잘 활용(活用)하여 국토(國土)를 보존(保存)시키고 동시(同時)에 초지생산성(草地生産性)도 높이는 방안(方案)이 인공초지조성(人工草地造成)에 있어 기대될 수 있는 방법(方法)으로 사료(思料)된다. 이의 대책(對策)의 일환으로 유실수(有實樹)와 초(草)와의 혼농림조성(混農林造成), 임간초지(林間草地)와 방목(放牧), 활엽수림하(闊葉樹林下)의 혼림초지(混林草地) 경사지(傾斜地)에 있어 대상식(帶狀式)과 세포식(細胞式)의 방풍(方風) 및 황폐방비림(荒廢防備林)에 의한 초지조성(草地造成) 또한 산능선부와 계곡부의 삼림(森林)을 보존(保存)시키는 초지조성법(草地造成法)을 제시(提示)하였다. 수광량(受光量)이 문제(問題)가 될 경우에는 간벌(間伐)과 가지치기 들(等)으로 조절할 수 있게 되고 예취작업(刈取作業)의 기계화상(機械化上)의 문제(問題)는 상하(上下) 수대(樹大)의 배열(配列) 또는 배식방법(配植方法)에 의해 조절할 수 있으므로 혼림초지조성(混林草地造成)이 초지생산성(草地生産性)에 하등의 영향을 주지 않을 것으로 사료(思料)되며 오히려 초생산량(草生産量)을 증대(增大)시키는 방법(方法)이 될 것이다.

• Korean Journal of Environmental Agriculture
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• v.35 no.3
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• pp.175-183
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• 2016

BACKGROUND: There's a long rainy season during the Summer in Northeast Asia, including Korea. Heavy rainfall during this season causes harm to tree's root, and damped injury in the pear has been continuously reported. Pear Research Institute is breeding damp resistant rootstocks and investigating their mechanisms to relieve damped damages in the pear.METHODS AND RESULTS: Seedlings of Pyrus betulaefolia and P. calleryana were divided into two groups: control and damped, respectively. Damped group was treated by constant irrigation for 77 days and control group was maintained to keep the soil moisture pressure between 0 and -10 kPa. After the treatment, we analysed trees' growth rate, chlorophyll content, amino acids and total phenolic compounds. As a result, P. betulaefolia was sensitive to damped treatment while P. calleryana did not have significant differences between the control and damped treatment. It was observed that total contents for phenolic compounds were dramatically increased in P. betulaefolia while trees' growth rate, chlorophyll b and general amino acid contents were lowered by damping treatment.CONCLUSION: In some pear cultivars, growth habit is suppressed by damped damage. Pyrus calleryana displayed tolerances to damped damage in growth rate and some organic compound contents compared to P. betulaefolia. So we recommend to exploit P. calleryana as a pear rootstock rather than using P. betulaefolia.

• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.3
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• pp.95-111
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• 2004

This research sought to determine the status of the installation and operation of composting facilities of domestic public resource-making facilities and come up with corresponding improvement measures. The composting facilities were the most extensively installed of related facilities with over a 0.5 ton treated volume per day. The monthly and yearly carry-in volume of food waste were found to stand at 1,101.7 tons per day and 930.9 tons per day, thus falling short of the average planned volume of 1,270.9 tons. Many composting facilities, which were installed in areas for which factory registration were not approved, did not get approvals. Composting facilities underwent operation stoppage mainly due to faulty fermentation and crushing equipment. Mainly metals contained in food waste caused faults to the crushing equipment, thus requiring a facility designing against faults and corrosion. The initial water content was found to stand at 50-60%, thus complying with the requirement. However, since the composting food waste had an appropriate mixture of sawdust, food waste, and returned compost, it should meet the initial conditions. For fermentation facilities, the duration time for fermentation was 15 days, and post-fermentation tanks required 21 days of duration time, thus establishing the minimum criteria. However, some facilities did not meet the requirements, taking more time in decomposition, thus suggesting a need to determine the duration time according to facilities. In composting food waste, microorganism-based thermal oxidizer-operated fermentation tanks should be used to ensure an economic operation. On the contrary, 14 out of 25 survey targets heated fermentation tanks in any form. These thermal facilities contain the growth of bacteria, lowering chemical reaction in composting; thus composting facilities should be basically designed to use microorganism-based thermal oxidizers in drying water. An average daily volume of food waste and supplementary materials that was injected in producing compost was 22.8 tons. This volume produced 7.3 tons of compost per day, decreasing 68%. Properties of produced compost were analyzed by its color, absence or presence of remaining decomposition heat, and smell, to assess the quality. As a result, the composting process was not properly installed nor operated in about 50% of composting facilities. Compost should be produced to be soil-friendly.

• Journal of Bio-Environment Control
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• v.20 no.2
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• pp.162-168
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• 2011

This study was carried out to investigate the plant growth of several Carex L. plants according to light intensity and soil depth planted on a green wall and roof, and to show basic data for the use of Carex L. plants in various forms. The temperature was dropt more in the green container compared to the normal especially during the genial weather from August to September. The plant growth of Carex testaceae, Carex oshimensis Evergold, and Carex ciliatomarginata Nakai was excellent at light intensity from 0 to $1799\;{\mu}M{\cdot}m^{-2}{\cdot}s^{-1}$, and that of Carex siderosticta Hance, Carex flagellifera Bronzita, Carex ornithopoda Variegata, and Carex morrowii Ice Dance were best in lower light intensity from 0 to $786\;{\mu}M{\cdot}m^{-2}{\cdot}s^{-1}$. The leaf color of the plants changed vividly as the light intensity grew lower and the visible value of the plants increased. There must be more considerations about the pattern changes in additory experiments. The water content in the soil depth of 10 cm was maintained higher than the other treatments because of no drainage layer. Most Carex L. plants grew excellent in the soil depth of 10 cm. However, Carex oshimensis Evergold, Carex siderosticta Hance, and Carex testaceae showed the best plant growth in soil depth 20 cm, and Carex morrowii Ice Dance and Carex ciliatomarginata Nakai in soil depth of 40 cm. Therefore, Carex L. plants could be recommended as materials for green roof because they also grew well in light soil depth of 10~20 cm.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.2
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• pp.145-156
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• 1996

The effects of priming with different polyethylene glycol (PEG 6, 000) solutions on the germination, emergence characteristics and early plant growth in rice, barley and wheat were investigated. Rice, barley and wheat seeds were subjected to various priming conditions of osmotic potentials (-0. 75, -1.00 and -1.50 MPa) of PEG, and incubation period were 5 days at 25, 20, 2$0^{\circ}C$, respectively. The percentage of water absorption was highest in barely, and lowest in rice, and all the treatments enhanced water absorption in barley, but showed no significant effects in rice and wheat. Respiration quotient was lower than none PEG treatment seeds, and those of barley and wheat were higher than rice regardless of PEG concentration, and that of rice increased with high PEG concentration. Total germination percentage of osmoconditioning seeds with PEG was higher than that of none treatment seed, and those of barley and wheat were significant. The artificially deteriorated seeds with PEG treatment seeds after ageing treatment could recover to nearly the same germination level as that of the control seeds. The effects of coating polymer were higher than osmoconditioning with PEG, and germination characteristics in rice showed varietal difference at PVP and waterlock at recoated seeds after PEG treatment. Osmoconditioning with PEG reduced mean germination and emergence time, but there was no difference among PEG concentrations. The plant height of PEG treaed seed in rice was taller and those of barely and wheat showed varietal difference, and those of polymer-coated seed after PEG treatment were different among the polymers. The dry weight of PEG treatment were different among the crops, and those were increased with the high PEG concentration. The emergence percentage of PEG-treated seed were higher than none-treated seed, and those were decreased with the increased PEG concentration, and the highest emergence percentage of rice, barley and wheat were 90, 50 and 50% soil moisture content, respectively. The time to emergence in rice was longer than barley and wheat, and those in rice was shortened in high soil moisture content, and barley and wheat were shortened in low soil moisture content.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.1
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• pp.11-19
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• 2016

Excessive application of nutrient supplement on the upland soil may increase the amount of discharge to surrounding water systems. The chemical fertilizer (CF), cow manure compost (CMC), and pig manure compost (PMC) are used as a nutrient supplement for cultivation of red pepper. Rice straws are widely used as a soil covering material in order to reduce weed occurrence, to protect soil moisture, and to supply organic matter in upland soil. This study was conducted to evaluate the furrow covering effect with rice straw on nutrient discharge in upland soil used for red pepper cultivation. The experimental plots of nutrient supplement were consisted of CF, CMC, and PMC and the amount of nutrient application were as recommended amount after soil test for red pepper cultivation. Each nutrient supplement treatment plot has no furrow covering (CFC) as a control and furrow covering with rice straw (FCS), respectively. Furrow covering with rice straw (FCS) of CF treatment and CMC treatment reduced the amount of T-N(total nitrogen) discharge by $1.4kg\;ha^{-1}$, $2.1kg\;ha^{-1}$, respectively, compared to control. While the amount of T-P(total phosphorus) discharge of the furrow covering with rice straw of CF, CMC, and PMC increased by $2.1kg\;ha^{-1}$, $2.1kg\;ha^{-1}$, and $0.2kg\;ha^{-1}$, respectively, compared to control. The phosphorus and nitrogen content of straw were 0.4 % and 0.3 % respectively. In addition, in three week the phosphorus was eluted from the straw which soaked in distilled water. Thus, it was assumed that T-P discharging originated from rice straw which applied as a furrow covering material. The furrow covering with rice straw reduced weed occurrence compared to control. But production of fresh red pepper was not influenced significantly by furrow covering with rice straw. In conclusion, excessive furrow covering with rice straw could induce T-P discharge from upland soil used for red pepper cultivation. Further studies are needed to evaluate the appropriate amount of rice straw as a furrow covering material.

• Magazine of the Korean Society of Agricultural Engineers
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• v.13 no.2
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• pp.2262-2275
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• 1971

Fourteenes rervoirs maintained by the local land improvement associations in the province of Chullabuk-Do and 20 reservoir maintained by thos in the province of Chullanam-Do, were surveyed in connection with a correction between storage capacity and sediment deposit. In addition to this survey, 3,347 of small reservoir, that lie scattered around in the above-mentioned two provinces were investigated by using existing two provinces were investigated by using existing records pertaining to storage capacity in the office of City and country, respectively. According to this investigation the following comclusions are derived. 1. A sediment deposition rate is high, being about $10.63m^3/ha$ of drainage area, and resulting in the average decreasc of storage capaity by 27.5%. This high rate of deposition coule be mainly attributed to the serve denudation of forests due to disorderly cuttings of trees. Easpecially, in small reservoir, an original average design storage depth of 197mm in irrigation water depth is decreased to about 140mm. 2. An average unit storage depth of 325.6mm as the time of initial construction is decreased to 226mm at present. This phenomena causes a greater shortage irrigation water, since it was assumed that original storage quantity was already in short. 3. Generally speaking, seepage rates through dam abutment intakepipe, etc, are high due to insufficient maintenance and management of reservoir. 4. It is recommended that sediment deposit should be dredged when a reservoir is dry in drought. 5. Farmers usually waste excessive irrigation water. 6. Water saving methods should be practiced by applying only necessary water for growing stage of rice. 7. In are as where water defficiency for irrigation is severe, a soil moisture content should be kept at about 70% by applying water once in several days. 8. Tube wells should be provided so as to exploit ground water and subsurface current below stream bed as much as possible. 9. If an intake weir was constructed, a water collection well should be built for the use in drought. 10. Water conservation should be forced by converting devastated forests contained in the drainage area of reservoir to protected forests so as to take priority of yrefor estation, gully control, the prohibition of disorderly cutting of trees, etc. 11. Collective rice nurseries should be adopted, and it should be recommended that irrigation water for rice nurseries is supplied by farmer themselves. 12. Sediment desposit in reservoir should be thoroughly dreged so as to secure a original design storage capacity. 13. The structure of overflow weir should be automatic so as to freely control flood level and not to increase dam height.

• Journal of Korea Water Resources Association
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• v.46 no.12
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• pp.1235-1247
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• 2013

This study is to evaluate the climate change impact on future storage behavior of Chungju dam($2,750{\times}10^6m^3$) and the regulation dam($30{\times}10^6m^3$) using SWAT(Soil Water Assessment Tool) model. Using 9 years data (2002~2010), the SWAT was calibrated and validated for streamflow at three locations with 0.73 average Nash-Sutcliffe model Efficiency (NSE) and for two reservoir water levels with 0.86 NSE respectively. For future evaluation, the HadCM3 of GCMs (General Circulation Models) data by scenarios of SRES (Special Report on Emission Scenarios) A2 and B1 of the IPCC (Intergovernmental Panel on Climate Change) were adopted. The monthly temperature and precipitation data (2007~2099) were spatially corrected using 30 years (1977~2006, baseline period) of ground measured data through bias-correction, and temporally downscaled by Change Factor (CF) statistical method. For two periods; 2040s (2031~2050), 2080s (2071~2099), the future annual temperature were predicted to change $+0.9^{\circ}C$ in 2040s and $+4.0^{\circ}C$ in 2080s, and annual precipitation increased 9.6% in 2040s and 20.7% in 2080s respectively. The future watershed evapotranspiration increased up to 15.3% and the soil moisture decreased maximum 2.8% compared to baseline (2002~2010) condition. Under the future dam release condition of 9 years average (2002~2010) for each dam, the yearly dam inflow increased maximum 21.1% for most period except autumn. By the decrease of dam inflow in future autumn, the future dam storage could not recover to the full water level at the end of the year by the present dam release pattern. For the future flood and drought years, the temporal variation of dam storage became more unstable as it needs careful downward and upward management of dam storage respectively. Thus it is necessary to adjust the dam release pattern for climate change adaptation.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.4
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• pp.269-274
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• 1994

An experiment was carried out to investigate the effects of irrigation period on the yield and quality of melon (Cucumis melo L.) cultivated in green house 1992~1993. Four different irrigation period was applied ; from transplanting to harvest(Irrigation I), from initial flowering to 35 days after flowering(Irrigation II), from initial flowering to 20 days after flowering(Irrigation III), from initial flowering to 5 days after flowering(Irrigation IV). The water was applied by drip irrigation when the soil water potential of 15cm depth reach at -0.5bar. The results obtained were as follows ; 1. The amount of water applied during the periods were 170.5mm, 145.0mm,126.9mm and 78.8mm for irrigation period I, II, III and IV, respectively. 2. Average evapotranspiration during the cultivation of melon was 3.31mm/day. Evapotranspiration was the highest at the period from 5days after flowering to 15days after flowering. 3. The total yield was increased with the higer amount of water applied, and the yield was in the order of Irrigation I, II, III and IV. However, the yield with economically high quality was the highest in Irrigation III. 4. The sugar content and quality of Net form were decreased with higher irrigation amount.

• Journal of Korean Society of Forest Science
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• v.47 no.1
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• pp.44-51
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• 1980

In order to find out the suitable methods that can omit the earth healing and increase the survival through improving the seedling-healing and transportable methods. Several trials with plastic vinyl have been done and its results are as follows: 1. Though P. rigitaeda seedling have been stored in the black and white vinyl sack for 35 days in the storehouse. This seedling have survived with very high percentage as Table 1. This means that the earth healing work at the nursery or planting area can be omitted if seedling sould be stored in the storehouse by using the vinyl sack. The possibilities of long-period storage in the black and white vinyl sack seem to be come from the reasons that air humidity in the sack is nearly 100% and its air temperature is only around $15^{\circ}C$ with very little difference between day and night time. This sack also can be utilized in place of the planting sack, and though this sack with seedling have been laid under direct sunshine for 1 to 2 days. Any difference between the sack stored in the storehouse has not been observed on the survival specially Table 2. 2. When the bundled seedling have been covered with the black and white vinyl instead of earth healing, even if these seedling have been laid for 18 days under the vinyl. This seedling show us high survival as Table 3. High humidity with nearly 95%, very little difference of air temperature between day and night time under the vinyl and not so big difference between out-and inside temperature could be reasons of high survival to be considered. So through covering by the black and white vinyl. The labour power for earth healing works can be saved also. 3. In order to protect the healed seedling from the direct sunshine and the eva-transpiration. Black vinyl net and reed mat could be effective for this purpose. Because vinyl net could intercept around one to third, reed mat two to third of total solar energy and also suppress more than 50% of total water loss by the transpiration.