• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.426-426
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• 2015

무경운 농법은 경작지의 토양을 교란시키지 않고 작물을 재배하는 방법으로, 토양의 물리성 개선과 토양 침식 예방, 생산비 절감 등의 효과가 있어 전 세계적인 인정을 받고 있는 농업기술이다. 그러나 아직까지 무경운의 재배 지속 기간 등 많은 의문이 제기되고 있으며, 국내 환경조건에 맞는 실험적인 연구가 미흡한 실정이다. 이에 본 연구에서는 최적관리기법의 하나인 무경운(No-till)을 적용한 밭의 오염물질 저감효과를 장기적으로 살펴보고자 2011년부터 2014년까지 4년간의 모니터링을 실시하였다. 무경운 농법을 적용하기 위하여 동계피복작물(밀, 보리)을 재배작물 정식하기 전해 겨울에 파종하여 이듬해 6월 말 수확하였다. 이후 7월에서 8월 사이 재배작물(들깨, 무)을 정식하였다. 시비는 2011년에는 축산퇴비, 2012년에는 축산액비 그리고 2013년과 2014년에는 화학비료를 시비하였으며, 매년 경운과 무경운의 시비량은 동일하게 처리하였다. 유출 시험포의 면적은 $150m^2$(폭 5 m, 경사장 30 m)이며, 8개(경사도 3% 4개, 경사도 8% 4개)의 시험포를 조성하여 각각 2개씩 경운(관행)과 무경운을 적용하였다. 모니터링은 재배작물(들깨, 무) 정식 이후부터 작물 수확 전까지 강우사상에 대하여 이루어졌으며, 연구기간동안 총 13회의 강우 사상에 대하여 조사를 실시하였다. 경운대비 무경운 시험포의 평균 오염부하 삭감율을 분석한 결과 경사도 3% 시험포의 경우 BOD는 35.1%, $COD_{Cr}$은 37.4% 그리고 영양염류인 TN과 TP는 각각 36.9%와 33.5%가 삭감된 것으로 조사되었으며, 경사도 8% 시험포의 경우 BOD가 36.4%, $COD_{Cr}$은 45.8%, TN과 TP는 각각 45.5%와 40.6%가 삭감된 것으로 나타났다. 우리나라에서는 경운(관행) 농법이 영농관리 차원에서 대부분 이용되고 있으나, 본 연구 결과에 기초할 때 무경운 농법으로 영농할 경우 강우유출수 및 하천으로 유입되는 비점오염부하를 효과적으로 제어할 수 있을 것으로 기대된다.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.814-818
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• 2011

The seasonal changes were evaluated in the soil microbial populations by selected media in an organic farming system (OFS) with no-till management compared to those in a conventional farming system (CFS) with tillage and synthetic amendments in a flooded paddy from 2009 to 2010. The populations of aerobic bacteria and fungi in the OFS were significantly higher than those in the CFS at the harvesting stages, whereas those of Gram-negative bacteria was significantly higher in the OFS than in the CFS before the submerging stages. In addition, populations of aerobic bacteria, Gram-negative bacteria, and fungi tended to rapidly decreased after the submerging stages may be due to insufficient oxygen. Gram-negative bacteria should be considered as potential factor responsible for the microbial population differentiation observed between the OFS and the CFS in flooded paddy fields.

• Applied Biological Chemistry
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• v.32 no.4
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• pp.357-361
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• 1989

Wheat Doenjang was manufactured by mixing various ratio of the soymilk residue with wheat Koji. As the result, the content of reducing sugar was increased till 50 days and decreased thereafter during aging of the mash. As the combination ratio of soymilk residue was increased, the content of reducing sugar was decreased and amino nitrogen content was increased prominently till 50 days in all testing samples but thereafter the increasing ratio was slowdowned. At the beginning of the aging the content of the amino nitrogen was higher in the testing sample which had higher combination ratio of soymilk residue but at the end of the aging the result was reversed. The content of the total acids was increased prominently till 40 days but thereafter the increasing ratio was slowdowned, and in each testing samples the difference in total acid content was extremely slight. In the color of each testing samples aged 80 days as the combination ratio of soymilk residue was increased, the lightness was increased, and the redness was decreased but the yellowness was increased. From the result of sensory evaluation test of wheat Doenjang aged 90 days, soy sprout Doenjang soup showed the best taste in control and as the combination ratio of soymilk residue was increased, the taste was dropped slightly but no significant differences was obtained among the testing sample A,B and C but between control and testing sample D there was significant difference. In the original taste of Doenjang, the control was the best and as the combination ratio of soymilk residue increased, the point was dropped but there were no significant differences between control and testing sample A and testing sample B and C.

• Applied Biological Chemistry
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• v.32 no.2
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• pp.98-103
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• 1989

For the effective use of soymilk residue (SR), by-product of soymilk production, rice Doenjang was manufactured. As the results, the contents of reducing sugar were increased till $40{\sim}50days$ in all samples and decreased thereafter during aging of the mash. The contents of amino nitrogen were prominently increased till 50days, but increasing ratio was slightly slowdowned thereafter. The higher mixing ratio of SR, the less were the contents of reducing sugar and amino nitrogen. The contents of total acid were also prominently increased till 30days, but were slowdowned thereafter and the differences among all treatments were small. As the mixing ratio of SR was increased, the lightness and the yellowness were increased and the redness was decreased in 80days aged samples. In sensory evaluation of 90days aged samples, control was the best in soy sprout Doenjang soup. As the mixing ratio of SR was increased, the taste was dropped slightly but no significant differences were obtained between control and sample A (rice koji 100, soybean 75, SR 25), and among A,B(rice koji 100, soybean 50, SR 50). C(rice koji 100, soybean 25, SR 75) and D(rice koji 100, soybean 0, SR100). In the original taste of Doenjang, the control was the best and as the mixing ratio of SR was increased, the point was dropped but there were no significant differences between control and A, and among A, B and C, and among B, C and D.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.5
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• pp.384-389
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• 2002

No-tillage (NT) practice for corn production has advantages of reduction of soil erosion and energy conservation. Research on effects of NT for sweet corn or super sweet corn is very limited. Hybrids of sugary (su) and shrunken-2 (sh2) were tested under NT and conventional tillage (CT) practices to investigate plant characters, ear characters, fresh yield, and grain yield. Sugary hybrids were Golden Cross Bantam 70 (GCB70), Sprint, Geumdanok, and Danok3. Shrunken-2 hybrids were BSS9472, Cambella90, GSS9299, Jubilee, KS-Y-65, and Chodangok1. Emergence rates under NT were lower than those under CT for su, while there was no difference between tillage systems for sh2. There were no differences between CT and NT for days to tasseling and silking, plant height, and ear height for both su and sh2. Ear characters such as ear length, number of kernel rows, number of kernels per row, and t100-kernel weight under NT were not significantly different from those under CT. There were no differences between two tillage practice for fresh and grain yield, rather they showed trend of increases under NT practices. Results from this trial indicate that NT practice for both su and sh2 cultivation may be possible to recommend to farmers.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.3
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• pp.127-132
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• 2006

This experiment was conducted to evaluate the effect of manure and chemical fertilizer on the forage yield and quality of oat at no-tillage. The experimental design was a randomized complete block design. The three treatments were: chemical fertilizer, manure fertilizer, and chemical and manure mixture. Seedling vigor was higher at chemical fertilizer than manure, but more greener at manure application than chemical fertilizer. Dry matter (DM) content of oat at manure was higher than chemical and mixture fertilizer (p<0.05). There was no difference in DM yield, TDN (total digestible nutrients) yield, and CP (crude protein) yield of oat at no-tillage system, but the fresh yield was significantly higher in chemical fertilizer compared to manure. The CP content for oat was significantly higher in manure than chemical fertilizer. However, no significant effects were observed for NDF (neutral detergent fiber), ADF (acid detergent fiber), TDN and RFV (relative feed value) in different fertilizer application. Based on the results of this study, manure don't affected forage production and quality of no-till oat except CP content because forage oat is used off-season crop.

• Journal of the Korean Society of Tobacco Science
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• v.23 no.1
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• pp.31-39
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• 2001

This study was carried out to investigate the changes of physical and chemical properties and the usability of long-term stored leaf tobacco. The physical chemical properties of the flue-cured and burley leaves produced in 1993, processed in 1994 were analysed from Nov. 1996 to Nov. 1999. The pH and moisture content in leaf decreased slowly until 4 years’storage after processing, while those of leaf changed little thereafter. However, total sugar content continuously decreased until 5 years after processing. The filling capacity increased and shatter resistance index decreased in long-term stored leaf. The sensory test, cilia stasis and the chemical components of cigarette smoke had no significant differences between short and long-term stored leaves. When the processed leaves were stored till 5 years after processing, there were no deteriorative effects on quality and usability of leaf tobacco. Therefore, it is considered that the processed leaf may be stored for 5 years or more under the inevitable situation.

• Korean Journal of Plant Resources
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• v.11 no.3
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• pp.252-256
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• 1998

A Study was conducted to investigate comparison of in vitro tuberization between normal and transgenic potato plantlets harboring adenosine deaminase gene in potato cultivar of Desiree. In time course study of in vitro tuberization, the rate of tuberization in four lines were increased till 6 weeks. but maintained stil after 7 weeks. Microtuber initiation of transgenic lines, 43 and 39 were faster than other lines, but no difference was observed after 5 weeks compared with normal plantlets. In all transgenic lines, the majoirty of microtubers produced were small(less than 100 mg) and medium(100-200mg) size rather than large size(more than 200 mg). Among 4 lines , line 9 produced the highest number of microtubers per each culture vessel. The results of this experiment suggest that there is no significant difference in microtuber production efficiency between normal and transgenic potatoes.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.95-100
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• 2020

Nifty Bank Index has started trading in futures and options (F&O) segment from 13^th June 2005 in National Stock Exchange. The purpose of the study is to enhance the literature by examining expiration effect on the price volatility and price reversal of Underlying Index in India. Historical data used for the current study primarily comprise of daily close prices of Nifty Bank which is the only equity sectoral index in India which is traded in derivatives market and its Future contract value is derived from the underlying CNX Bank Index during the period 1^st January 2010 till 31^st March 2020. To check stationarity of the data, Augmented Dicky Fuller test was used. The study employed ARMA- EGARCH model for analysing the data. The empirical results revealed that there is no effect on the mean returns of underlying Index and EGARCH (1,1) model furthermore shows there is existence of leverage effect in the Bank Index i.e., negative shocks causes more fluctuations in the Index than positive news of similar magnitude. The outcome of the study specifies that there is no effect on volatility on the underlying sectoral index due to expiration days and also observed no price reversal effect once the expiration days are over.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.5
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• pp.564-570
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• 1997

Field experiments were carried out to investigate the effects of different residue treatment of vetch sward on soil improvement, rice growth and grain yield from 1995 to 1996. With Chinese milkvetch, pH, Ca, and Mg of paddy soil were increased in subsoil(10~20cm soil depth), and organic matter, P$_2$ $O_{5}$, and K were increased in top soil (0~10cm soil depth). Redox potential of the paddy soil with milkvetch residue was severely reduced at earlier flooding period, and recovered gradually as rice growth continued. Weeds were more abundant in the paddy with unchanged vetch stand. The most dominant weed species in the paddy soil with vetch sward residue was Echinochloa crus-galli, followed by Leersia japonica, Polygonum hydropiper in the order of abundance. Seedling establishment ratio of rice directly sown over vetch-sward was lower than in conventional tillage paddy(no-vetch, tilled) condition. Rice growth pattern, however, was not significantly affected by vetch sward treatments. The number of tillers per square meter and plant height at heading date were not significantly different among the vetch-sward treatments. Grain yield was the highest in plough of vetch vegetation, followed by conventional (no-vetch, tilled), live-mulching of vetch, vetch-removed, and vetch-desiccated by weedcide. The whole grain rice yield was the lowest in vetch-desiccated by weedcide.