• Title/Summary/Keyword: 퇴비화 과정

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Comparison of Volatile Organic Compound and Volatile Fatty Acid Concentration in Feces and Urine of Finishing Pigs (초지환원용 비육돈의 분과 뇨에 있어서 휘발성유기물과 휘발성지방산 농도 비교)

  • Cho, Sung Back;Hwang, Ok Hwa;Yang, Seung Hak;Kwag, Jeong Hoon;Choi, Dong Yun;Yang, Sung Bong;Kim, Doo Hwan;Park, Sung Kwon
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.34 no.2
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    • pp.120-124
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    • 2014
  • This study was performed to compare the level of odorous compounds in feces and urine of finishing pigs. Feces and urine from 16 finishing pigs were separately collected for 28-d. Concentrations of volatile organic compound (VOC; phenols and indoles) and volatile fatty acid (VFA; SCFA and BCFA) were measured in feces and urine. Amount of phenols and p-cresol was higher (P<0.05) in urine than in feces. Urinal levels of phenols and p-cresol were 257.8 ppm and 250.9 ppm, and those of fecal phenols and p-cresol were 0.50 ppm and 0.05 ppm, respectively. There was no difference in concentration of indoles from feces (1.0 ppm) and urine (1.8 ppm). Short chain fatty acid (SCFA) level in urine was higher (P<0.05) than in feces showing 4,547 ppm and 863 ppm, respectively. Proportion of acetic acid to total SCFA was higher in urine (94%) than in feces (66%). However, level of branched fatty acid (BCFA) was greater in feces (118 ppm) compare to that of urine (87 ppm). Odorous compounds analyzed in the current study, phenols and SCFA, were contained more in urine than in feces. Greater amount of VFA is typically found in feces than in urine since it is generated in the large intestine. However, urine contained more VFA than feces in the current study. Therefore, it will be necessary to exploit odor reducing techniques especially for pig urine as grassland fertilizer.

Biological treatment process for Food wastewater Using ER-1 bioreactor (다단 수직형 호기성반응기(ER-1)를 이용한 음식물 폐수의 생물학적 처리기술)

  • Lee, Jae-ki;Choi, Hong-Bok;Shin, Eung-Bai;Park, Ju-Hyoung;Choi, Eun-Ju;Kim, Jung-Rae;Park, Young-Sook
    • Journal of the Korea Organic Resources Recycling Association
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    • v.14 no.4
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    • pp.113-120
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    • 2006
  • Wastewater generated through the food waste recycling process have known high concentration, BOD 20,000~150,000 mg/L, which has to treat to the proper level because of a ban on reclamation. But it is impossible to treat less than 10 days by existing water treatment plant. Ecodays Ltd. is to treat this wastewater during 2~4 days by ER-1, which can simultaneously induce the modified PFR(Plug Flow Reactor) of the oxygen transfer rate, MLVSS concentration, and influent concentration to top from bottom of reactor. We tested the pilot test about low concentration food wastewater(BOD 16,500 mg/L) and high concentration food wastewater(64,431 mg/L) at the food waste recycling plant of H-Gun(20t/d). Hydraulic retention time(HRT) of ER-1 for low concentration food wastewater is 2.5day. In low concentration conditions, ER-1 treatment efficiency is to appear BOD 99%, COD 98%, TN 97%, and TP 96%. While ER-1 process for high concentration food wastewater treatment is composed 2 stages, which are to be HRT 2.5day for law wastewater and HRT 1.5 day for secondary treatment. In high concentration conditions, ER-1 treatment efficiency is to appear BOD 97%, COD 84%, TN 66%, and TP 95%. It is treated without temperature control about high temperature($50^{\circ}C$) to appear low treatment efficiency in high concentration conditions.

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Development, Current Issues and Prospects of Organic Agriculture Movement in Korean

  • 손상목;정길생
    • Korean Journal of Organic Agriculture
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    • v.5 no.2
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    • pp.71-84
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    • 1997
  • 유기농산물은 질 좋은 농산물이며 그 생산농법이 환경친화적인 것으로 이해하고 있어 참여농가수도 증가일로에 있고 소비자들에 의한 유기농산물 구입 역시 점차 증가 추세에 있으나, 한국유기농업은 국제적 유기농업에 다르게 잘못 정의된 채 확산되고 있어, 그 핵심기술의 환경영향평가의 과학화에 대한 시대적 요청과 유기농업 기본규약 제정 필요성이 학계 일부에서 제기 되고 있는 등 한국유기농업은 최근 발전을 위한 진통을 겪고 있다. 이에 본 논문은 한국유기농업이 태동된 배경과 70년대 말로부터 80년대 초에 걸쳐 태생된 한국유기농업이 국민적 관심을 얻게된 배경과 정농회, 한국유기농업협회, 한국자연농업협회, 한 살림 등의 유기농업단체와 한국유기농업학회, 환경보전형농업생산소비단체협의회, 흙살림연구소 등의 발전과정 및 활동을 소개하고 있다. 또한 서울에서 개최된 IFOAM Asia대회, 한국자연농업협회의“자연농업연구소”, 한국유기농업협회의“건강과 자연농업”등에 관해서 뿐만 아니라 우리 정부의 21세기를 향한 농림환경정책중 유기농업부문에 대한 각종 장기지원책, 즉 중소농대책의 일환의 유기-자연농업 지원책, 유기농산물에 대한 품질인증제 및 팔당상수원보호구역내 유기농업지원 등이 소개되고 있다. 한편 한국유기농업기술의 핵심내용이었던 유기질비료 과다시용 문제가“유기농산물 채소의 고 질산염 함량”으로 촉발된 식품안정성 논쟁 후에 유기질비료의 추천시용량이 다다익선적 개념에서 80t/㏊으로 낮아졌다가 다시 50t/㏊으로 낮아졌으며 1996년 6월부터는 20t/㏊로 크게 낮추어 졌음을 보고하고 있다. 또한 일부 선도적 유기독농가의 경험적 기술이 토대가 되어 성립된 현 유기농업기술은 과학적 기술검증을 거쳐야 함과 퇴비사용 만으로 실시하는 현 유기농업 기술에 의해 야기되는 근권내 질산 미치 인산염 집적을 회피하기 위해서는 윤작, 녹비작물 및 두과작물의 재배로 토양비옥도 향상을 통한 유기농업 기술 개발이 필요하며 IFOAM 기본규약과 FAO/WHO Codex의 핵심 내용을 수용하는 한국유기농업 기본규약 제정이 제정이 절실히 요구됨을 강조하고 있다. 마지막으로 한국유기농업의 핵심기술에 대한 환경영향평가와 기본규약제정 필요성을 역설하고 한국유기농업의 과학화와 질 좋은 유기농산물 생산을 위해 노력하고 있는 소비자 문제를 연구하는 시민의 모임 등 몇몇 단체들의 최근 활동이 언급되고 유기농업에 대한 농과대학내 연구와 강의 등이 소개되었다.

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Mineralization of Cattle Manure Compost at Various Soil Moisture Content (우분퇴비 시용후 토양수분 조절에 따른 질소 및 탄소의 전환)

  • Kim, P.J.;Chung, D.Y.;Chang, K.W.;Lee, B.L.
    • Korean Journal of Environmental Agriculture
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    • v.16 no.4
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    • pp.295-303
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    • 1997
  • To investigate the transformation characteristics of nitrogen and carbon from cow manure compost amended in soil under different moisture conditions, dynamics of nitrogen and carbon were determined periodically for 15 weeks of aerobic incubation at room temperature during July${\sim}$November, 1996. Cow manure compost matured with mixing saw dust was amended with the 4 ratios (0, 2, 4, 6%(wt/wt)) in Ap horizon soil, which collected from green house in Yesan, Chungnam. Moisture was controlled with 0.2, 0.3, 0.4, and 0.5 of mass water conte nt (${\theta}$m) to air dried soil, and water loss was compensated at every sampling. During incubation, soil pH was decreased continuously, that was caused by hydrogen generated from nitrification of ammonium nitrogen. And pH became higher with inclining cow manure compost amendment and water treatment, that meaned the increase of mineralization of organic-N to $NH_4\;^+-N$. Total nitrogen was reduced with increasing water content, but total carbon showed the contrast tendency with that of nitrogen. Therefore, C/N ratio slightly decreased in the low water condition (${\theta}$m 0.2) during incubation, but increased continuously in high water condition over ${\theta}$m 0.4. As a result, it was assumed that soil fertility is able to be reduced in the high water content over available water content. Nitrate transformation rate increased lasting in the low water content less than ${\theta}$m 0.3. Itdropped significantly in the first $2{\sim}3$ weeks of incubation over ${\theta}$m 0.4. In particular, nitrate was not detected in ${\theta}$m 0.5 of water content after the first $2{\sim}3$ weeks. In contrast, ammonium transformation was inclined with increasing water treatment. Nitrogen mineralization rate, which calculated with percentage ratio of (the sum of ex.$NH_4\;^+-N$ and $NO_3\;^--N$)/total nitrogen, was continuously increased in the low water content of ${\theta}$m 0.2 and 0.3. But it saw the different patterns in high water content over ${\theta}$m 0.4 that was drastically declined in the initial stage and then gradually inclined . From the above results, nitrogen transformation patterns differentiated decisively in water content between ${\theta}$m 0.3 and 0.4 in soil. Thus, it is very important for the maintain of suitable soil water content to enhance fertility of soil amended with manure compost. However, excess treatment of manure compost might enhance the possibility of contamination of small watershed and ground water around agricultural area.

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A Study of Foodwaste Treatment Technology Using Eatrhworm (지렁이를 이용한 음식물쓰레기 처리에 관한 연구)

  • Lee, Chang-Ho;Lee, Jong-Min;Bae, Sung-Geun;Jeon, Sung-Kyun;Kim, Jong-Oh
    • Journal of the Korea Organic Resources Recycling Association
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    • v.13 no.1
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    • pp.71-78
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    • 2005
  • This study was performed to obtain the basic data on current situations and challengeable aspects of vermicomposting industries in Korea and to develope foodwaste treatment technology using earthworm. Pre-treatment process of food waste consists of cleaning, grinding, mixing and others, and salinity of food waste was 0.7% on average, thus not suitable for feed of worms. When applying wash water and going through the cleaning process, however, salinity was dropped to 0.38%, indicating that cleaning process applying wash water is necessary to control the proper salinity for growth of worms. In the food waste processing experiment applying worms, it has been presented that smaller particles induce higher processing efficiency. As a result, food waste processing by worms is possible through maintaining the suitable environment for survival of worms from input process to generation of cast. Cast generated after processing food waste was proved to be most suitable for product standard of compost thus cast is presented to be recycled after processing the food waste applying the worms.

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An Exploration on Food Waste Management of Local Governments (전국 지방자치단체의 음식물쓰레기 관리 분석)

  • Oh, Jeongik;Lee, Hyunjeong
    • Journal of Korean Society of Environmental Engineers
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    • v.38 no.3
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    • pp.101-109
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    • 2016
  • This research is to explore food waste management across local governments. In particular, pubic administration on food waste, food waste management (from generation to disposal) and civil complaints in jurisdiction are examined. In doing so, a self-administered questionnaire survey was conducted among civil officers in charge of food waste management, and all the collected responses were statistically analyzed. The main results were as follows: public spending on food waste management was a little larger in metropolises than in provincial cities, and the largest food waste source was identified as households (in housing). While regular collection of food waste by trucks was the most common transport method adopted by local governments, resource recovery for compost/fertilizer production was widely used. Also, most of the respondents agreed that the current approach to food waste handling practices are necessarily replaced with more advanced technology converting waste into energy or fuel. Further, it's found that the civil complaints on food waste management were largely categorized into 3 groups - food waste handling, civil service and food waste retrieval. Therefore, the findings indicate that the development and application of no-food waste or waste-to-resource systems are effective in housing estates where large amount of food waste is generated and eliminated.

The Patterns of CH4 and N2O fluxes from used Litter Stockpile from Korean Native Cattle (Hanwoo) (사용한 한우 깔짚에서 배출되는 CH4 및 N2O의 배출 특성)

  • Park, Kyu-Hyun;Choi, Dong-Yoon;Yoo, Yong-Hee
    • Journal of Animal Environmental Science
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    • v.18 no.3
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    • pp.145-150
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    • 2012
  • This study was conducted to measure methane ($CH_4$) and nitrous oxide ($N_2O$) emissions from the 6 month old litter stockpile used for korean native cattle (Hanwoo) from August 3, 2007 to October 4, 2007. Daily mean $CH_4$ emissions was peaked to 273.013 ${\mu}g\;m^{-2}\;s^{-1}$ (SE : ${\pm}1.047{\mu}g\;m^{-2}\;s^{-1}$) on first day and then gradually decreased to 2.309 ${\mu}g\;m^{-2}\;s^{-1}$ (SE : ${\pm}0.061{\mu}g\;m^{-2}\;s^{-1}$) at the end of this experiment. Daily mean $N_2O$ emissions was as little as 0.269 ${\mu}g\;m^{-2}\;s^{-1}$ (SE : ${\pm}0.018{\mu}g\;m^{-2}\;s^{-1}$) on first day, but exponentially increased up to 3.569 ${\mu}g\;m^{-2}\;s^{-1}$ (SE : ${\pm}0.454{\mu}g\;m^{-2}\;s^{-1}$) on 43rd day and then slowly decreased to 1.888 ${\mu}g\;m^{-2}\;s^{-1}$ (SE : ${\pm}0.012{\mu}g\;m^{-2}\;s^{-1}$) at the end of this experiment. Carbon dioxide equivalent ($CO_2$-eq), calculated by global warming potentials of $CH_4$ or $N_2O$, of $CH_4$ on first day occupied approximately 99% of sum of $CO_2$-eq of $CH_4$ and $N_2O$. Methane emissions decreased and $N_2O$ emissions increased so that $CO_2$-eq ratio of $CH_4$ to $N_2O$ was 50:50 on 34th day. The effect of $N_2O$ on the ratio was increase thereafter. The ratio of daily mean $CH_4$ and $N_2O$ emissions to daily error of the mean was calculated to find daily fluctuation of $CH_4$ and $N_2O$ emissions. The ratio of $CH_4$ was less than 1.0% till 11th day but increased to 10.9% on 57th day. The ratio of $N_2O$ (0.4%~51.0%) was higher than that of $CH_4$, showing high in early stage and then gradually decrease, which was different from the pattern of $CH_4$. The ratio of daily mean emissions to daily error of the mean was little in case of active $CH_4$ or $N_2O$ generation period, which would be caused by the temporal and spatial heterogeneity of composting process. Hence more air supply on early stage to decrease $CH_4$ generation and proper turning to reduce spatial heterogeneity are needed to mitigate greenhouse gas emissions.

The City Rhinoreaction Research of the Corn Feed for the Heavy Metal Removal of the Pig Ordure Sludge Using the Citric Acid and Stability Evaluation (구연산을 이용한 돈분슬러지의 중금속 제거 및 안정성평가를 위한 사료용 옥수수의 시비반응 연구)

  • Oh, Tae-Seok;Kim, Chang-Ho;Choi, Bong-Su
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.31 no.4
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    • pp.395-408
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    • 2011
  • The study which it sees exclusions the copper and the zinc which contain in pig sludge, It study pig sludge resources fertilizer production which are rational, pig sludge resources fertilizers after seeding, silage corn it investigates growth characteristics and forage value, the result which investigates pig sludge resources fertilizers effectiveness with afterwards is same. With fertilizer ingredients in pig sludge chemical qualities, the content of the nitrogen and the phosphoric acid comes 4.4% to be 6.29%, pH 7.02 and content of the copper and the zinc which is a heavy metal which contains in pig sludge with 805 mg/kg and 1,704 mg/kg, it is a restrictive standard of the fertilizer, 300 mg/kg and 900 mg/kg it sees to be high, it manufactures citric acid 1 hydrate with the organic acid solution, heavy metals of pig sludge where it is a mixture ratio of the organic acid solution, it divides to 25%, 50%, 75% and 100% 4 kind levels, the result which measures the heavy metal exclusion ratio of the copper and the zinc, the mixture ratio of the organic acid solution to be many exclusion ratio of the copper and the zinc is showing a just interrelation, from organic acid solution 100% level content of pig sludge remains copper and zinc 330.03 mg/kg and 41.28 mg/kg, it shows the exclusion ratio of copper 59% zinc 97%. 'Cheonganok' growth characteristics with citric acid 1 hydrate, Treatment 2 and control growth characteristics etc, it exclusion the copper and the zinc it doesn't appear on significant difference statistically but, treatment 3 after only pig sludge in resources disposal where it seeding, growth characteristics of leaf area etc. is badness, it compares in control and treatment 2 the growth characteristics badness, it is appearing, it is caused by with disease and insects occurrence of $Ostrinia$ $furnacalis$ and brown spot, the damage was many. From forage value, Treatment 2 where it exclusion the heavy metal with the citric acid 1 hydrate with control it compares and there are not significant difference from crude protein and ADF and NDF contents etc., seeding only Pig Sludge in resources disposal treatment 3, it is caused by with $Ostrinia$ $furnacalis$ etc., trunk and aging of the leaf to be high ADF content is low. but from crude protein, the nitrogen ingredient which pig sludge has and interrelation it seemed and high numerical value were confirmed.

Study on the Technological System of the Cooperative Cultivation of Paddy Rice in Korea (수도집단재배의 기술체계에 관한 연구)

  • Min-Shin Cho
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.8 no.1
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    • pp.129-177
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    • 1970
  • For the purpose of establishing the systematized technical scheme of the cooperative rice cultivation which has most significant impact to improve rice productivity and the farm management, the author have studied the cultivation practices, and the variation of rice growth and yield between the cooperative rice cultivation and the individual rice cultivation at random selected 18 paddy fields. The author also have investigated through comparative method on the cultivation practices, management, organization and operation scheme of the two different rice cultivation methods at 460 paddy fields. The economic feasibility has been ana lysed and added in this report. The results obtained from this study are summarized as follows; 1. In the nursery, the average amount of fertilizer application, especially, phosphate and potassium, and the frequency of chemicals spray for the disease, insect and pest control at the cooperative rice cultivation are significantly higher than those of the individual rice cultivation. 2. The cultivation techniques of the cooperative rice farming after the transplanting can be characterized by a) the earlier transplanting of rice, b) the denser hills per unit area and the lesser number of seedlings per hill, c) the application of larger quantities of fertilizer including nitrogen, phosphate and potassium, d) more divided application of fertilizers, split doses of the nitrogen and potassium, e) the increased frequencies of the chemicals spray for the prevention of disease, insect and pest damages. 3. The rate of lodging in the cooperative rice cultivation was slightly higher than that of the individual rice cultivation, however, the losses of rice yield owing to the occurrence of rice stem borer and grass leaf roller in the cooperative rice cultivation were lower than that of the individual rice cultivation. 4. The culm length, panicle length, straw weight and grain-straw ratio are respectively higher at the cooperative rice cultivation, moreover, the higher variation of the above factors due to different localities of the paddy fields found at the individual rice cultivation. 5. The number of panicles, number of flowers per panicle and the weight of 1, 000 grains, those contributing components to the rice yield were significantly greater in the cooperative rice cultivation, however, not clear difference in the maturing rate was observed. The variation coefficient of the yield component in the cooperative cultivation showed lower than that or the individual rice cultivation. 6. The average yield of brown rice per 10 are in the cooperative rice cultivation obtained 459.0 kilograms while that of the individual rice cultivation brought 374.8 kilograms. The yield of brown rice in the cooperative rice cultivation increased 84.2 kilogram per 10 are over the individual rice cultivation. With lower variation coefficient of the brown rice yield in the cooperative rice cultivation, it can be said that uniformed higher yield could be obtained through the cooperative rice cultivation. 7. Highly significant positive correlations shown between the seeding date and the number of flowers per panicle, the chemical spray and the number of flowers per panicle, the transplanting date and the number of flowers per panicle, phosphate application and yield, potassium application and maturing rate, the split application of fertilizers and yield. Whilst the significant negative correlation was shown between the transplanting date and the maturing rate 8. The results of investigation from 480 paddy fields obtained through comparative method on the following items are identical in general with those obtained at 18 paddy fields: Application of fertilizers, chemical spray for the control of disease, insects and pests both in the nursery and the paddy field, transplanting date, transplanting density, split application of fertilizers and yield n the paddy fields. a) The number of rice varieties used in the cooperative rice cultivation were 13 varieties while the individual rice cultivation used 47 varieties. b) The cooperative rice cultivation has more successfully adopted improved cultivation techniques such as the practice of seed disinfection, adoption of recommended seeding amount, fall ploughing, application of red soil, introduction of power tillers, the rectangular-type transplanting, midsummer drainage and the periodical irrigation. 9. The following results were also obtained from the same investigation and they are: a) In the cooperative rice cultivation, the greater part of the important practices have been carried out through cooperative operation including seed disinfection, ploughing, application of red soil and compost, the control of disease, insects and pests, harvest, threshing and transportation of the products. b) The labor input to the nursery bed and water control in the cooperative rice cultivation was less than that of the individual rice cultivation while the higher rate of labor input was resulted in the red soil and compost application. 10. From the investigation on the organization and operation scheme of the cooperative rice cultivation, the following results were obtained: a) The size of cooperative rice cultivation farm was varied from. 3 ha to 7 ha and 5 ha farm. occupied 55.9 percent of the total farms. And a single cooperative farm was consisted of 10 to 20 plots of paddies. b) The educational back ground of the staff members involved in the cooperative rice cultivation was superior than that of the individual rice cultivation. c) All of the farmers who participated to the questionaires have responded that the cooperative rice cultivation could promise the increased rice yield mainly through the introduction of the improved method of fertilizer application and the effective control of diseases, insects and pests damages. And the majority of farmers were also in the opinion that preparation of the materials and labor input can be timely carried out and the labor requirement for the rice cultivation possibly be saved through the cooperative rice cultivation. d) The farmers who have expressed their wishes to continue and to make further development of the cooperative rice cultivation was 74.5 percent of total farmers participated to the questionaires. 11. From the analysis of economical feasibility on the two different methods of cultivation, the following results were obtained: a) The value of operation cost for the compost, chemical fertilizers, agricultural chemicals and labor input in the cooperative rice cultivation was respectively higher by 335 won, 199 won, 288 won and 303 won over the individual rice cultivation. However, the other production costs showed no distinct differences between the two cultivation methods. b) Although the total value of expenses for the fertilizers, agricultural chemicals, labor input and etc. in the cooperative rice cultivation were approximately doubled to the amount of the individual rice cultivation, the net income, substracted operation costs from the gross income, was obtained 24, 302 won in the cooperative rice cultivation and 20, 168 won was obtained from the individual rice cultivation. Thereby, it can be said that net income from the cooperative rice cultivation increased 4, 134 won over the individual rice cultivation. It was revealed in this study that the cooperative rice cultivation has not only contributed to increment of the farm income through higher yield but also showed as an effective means to introduce highly improved cultivation techniques to the farmers. It may also be concluded, therefore, the cooperative rice cultivation shall continuously renovate the rice production process of the farmers.

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Studies on the Induction of Available Mutants of Takju Yeast by UV light Irradiation (part 2) -On the Physiological Characteristics of the Mutants- (자외선조사(紫外線照射)에 의한 탁주효모(酵母)의 변이주육성(變異株育成)에 관한 연구 (제 2 보) -변이주(變異株)의 생리적성질(生理的性質)에 관하여)

  • Kim, Chan-Jo;Oh, Man-Jin;Kim, Seung-Yul
    • Applied Biological Chemistry
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    • v.18 no.1
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    • pp.16-22
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    • 1975
  • This experiment was carried out to investigate the physiological characteristics of two original yeasts, 5-Y-5 and 6-Y-6, which selected from 24 Takju yeasts and three mutants, 30-24,30-81 and 40-27. induced from two original yeasts by the irradiation of UV light. The results were summarized as follows. 1) Alcohol tolerances of three mutants were decreased in some degree as compared with those of original yeasts. 2) Tolerances of lactic and citric acids of acid producing mutant 30-81, was increased than those of original yeasts. 3) In the case of using ammonium sulfate as a nitrogen source, two original yeasts and three mutants required Ca-pantothenate as a essential growth factor and four strains of yeasts except the mutant, 30-81, required biotin as a stimulated growth factor, When asparagine was used as a nitrogen source, two original yeasts and three mutants showed the same as above result but the stimulated effect of biotin was far less. 4) Propagation powers of the mutants were weaken than those of original yeasts, particular that of acid producing mutant, 30-81, was the weakest in the three mutants. 5) The optimum temperature for fermentation of original yeasts were $30^{\circ}C\;to\;35^{\circ}C$ but three mutants were $25^{\circ}C\;to\;30^{\circ}C$. 6) The optimum pH for fermentation of original yeasts were pH 5 to 6, and there is no appreciable difference between original yeasts and three mutants. The fermentation power of mutant,30-81, was decreased more rapidly than those of other mutants according to approach neutral. Three mutants were more sensible to heat than original yeasts. 7) Two original yeasts and three mutants were inhibited more over 20 percent of sugar for fermentation and three mutants were more sensible to sugar concentration than original yeasts.

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