• Journal of Bio-Environment Control
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• v.20 no.2
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• pp.134-138
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• 2011

This study was conducted to evaluate the effects of seeding time of ryegrass+hairy vetch on the nutrient contribution and growth of the crops. in order to develop utilization of cover crops as an organic nutrient source in a pear orchard. The study was conducted at a diligent farmer in Boseong in Chonnam, and the both ryegrass and hairy vetch applied on 1) 27 September, 2) 15 October, 3) 8 November, and 4) 10 December of 2008 as a cover crop treatment. Sod culture was refereed as a control. Growth of ryegrass was not affected by seeding time, but hairy vetch had fewer leaf and shoot number as seeding time advanced from September to December, and the similar trend was observed for the dry weight of the crops by seeding time. Seeding of cover crop on September was 2.6 times greater dry weight than those of the sod culture (362 kg/10a). Higher N concentration in cover crops occurred on early seeding time, and estimated N contribution from the cover crops was 16.9 kg/10a, which was 2.6 times greater than those of sod culture. $P_2O_5$ production from the cover crops was the greatest on seeding of October, and $K_2O$ production increased at earlier seeding time.

• Economic and Environmental Geology
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• v.45 no.1
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• pp.23-30
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• 2012

Major ions and nitrogen isotopic analyses were performed to determine the geochemical characters and to identify the source of nitrate of the shallow groundwater around agricultural field in the Youngdong area. The pH value of groundwater ranges from 60. to 8.2 (pH 7.2, mean). The average of EC, Eh and DO is 369 ${\mu}S/cm$ (70~729 ${\mu}S/cm$), 165.6 mV (29~383.2 mV), 4.3 mg/L (1.8~8.0 mg/L) respectively. The ion concentraion of groundwater was in the order of $Ca^{2+}$>$Na^{2+}$>$Mg^{2+}$>$K^{2+}$ and ${HCO_3}^-$>${NO_3}^-$>${SO_4}^{2-}$>$Cl^-$>$F^-$. Most of groundwater is Ca-$HCO_3$ type. The groundwater was affected by water-rock interaction in the shallow depth. Some groundwater is Ca-Cl or Na-$HCO_3$ (2.5%) type that was due to agricultural activities. The $NO_3$_N concetration of grondwater range from 10.2 mg/l to 26.9 mg/l, which show that this area is under nitrate pollution. ${\delta}^{15}N-NO_3$ value of the groundwater is the origins of are a combination of animal wastes and man-made fertilizers.

• Applied Biological Chemistry
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• v.46 no.2
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• pp.134-139
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• 2003

To establish the fertilization condition to increase the productivity of Chasanthemum boreale M. with high quality, the effects of three nutrients (N, P, K) on the yields and the effective components were investigated in the pot scale. NPK was applied by chemical fertilizers with $(N-P_2O_5,-K_2O=250-160-160\;kg/ha)$ as a main treatment, and NP $(N-P_2O_5,-K_2O=250-160-160\;kg/ha)$, NK $(N-K_2O =250-160\;kg/ha)$, and PK $(P_2O_5K_2O=160-160\;kg/ha)$ treatments were settled as comparison. Dry yields of C. boreale M. was increased significantly to 4 fold higher by nitrogen. Nitrogen increased apparently plant growth and inorganic nutrient uptake. In the flower, which is most useful and edible part as a herbal medicine, main amino acids were glutamic acid and aspartic acids, and the total content was increased significantly by three elements of application. In addition, the content of cumambrin A, which is known to have the effect of blood-pressure reduction, was increased source to 6.2 times by nitrogen higher than that in PK treatment. Potassium was more effective in biosynthesis of cumambrin A than phosphorus, but the biological pathway was not clear, still.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.1
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• pp.1-10
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• 2016

The objective of this study was to investigate the effects of farming methods on mass balance from paddy rice. The experiment fields were established at Chunpo-myeon, Iksan-si in the Saemangeum watershed. Experiment was performed during the growing season to assess water and mass balances of the study field in 2013. The three different farming practices were applied: conventional (TR-A), drainage outlet heighten (TR-B) and slow release fertilizer use (TR-C). Drainage amount from TR-B was reduced by 28.5 % compared to the TR-A, while the amount from TR-C was similar to that of TR-A. Overall, nutrient concentration of paddy water were similar among the treatments except for T-P. Mean T-P concentration from TR-C was lower than that from TR-A (p-value<0.05). As the results of mass balance, TR-B appeared to reduce nutrient surface loss, substantially by 30.9 % and 40.8 % for T-N and T-P an compared to TR-A. TR-C treatment also demonstrated nutrient load reduction by 38.2 % and 40.1 % for T-N and T-P. The study results showed that water and fertilizer treatments are effective in surface load reduction respectively from paddy fields, and, long-term monitoring and evaluation is needed to confirm the reduction.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.5 no.2
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• pp.45-49
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• 1972

The following are some results obtained from a series of experiments in rotifer culture and its usage for the food of tiny fish fry: 1, Outdoor concrete ponds, each being $16m^2$, were used to culture the rotifers, Brachionus calyciflorus, and Filinia longiseta. Brachionus calyciflorus usually attained the population of about 100 individuals per ml of pond water. Dipterex was usually applied to control Daphni,a and other crustaceans that generally appear and feed on rotifers. A concentration of 0.16 to 0.2 ppm in the pond water was sufficiently effective to control these natural enimies of rotifers. Poultry dung was very effectively used to multiplicate rotifers. The fertilization ratio was about 8 kg each pond with 30cm depth of water. 2. The tiny rotifer, Filinia longiseta attained a very high population density of about 1,000 individuals per ml of pond water, but they were very sensitive to dipterex, and for this aspect future investigation may be needed. 3. In the outdoor ponds, the multiplication of rotifers significantly decreased when the water temperature falls to about $20^{\circ}C$ in autumn. 4. In the laboratory room, unicellular planktonic algae such as Scenedesmus or Chlorella, as the food of rotifers, were collected from the outdoor ponds by dipping them together with water, and were effectively used for the culture of Brachionus calyciflorus. If the planktonic algae are cultured in specially designed containers, the sun-light would be the most effective means as the source of light. 5. Brachionus calyciflorus cultured in the outdoor ponds by the dipterex controlled method was highly efficient to rear the early fry of marble gourami. The dipterex content mixed in the water to control the crustacean emmies of rotifers sieved no harm to the gourami fish fry.

• Korean Journal of Environmental Agriculture
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• v.37 no.1
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• pp.28-33
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• 2018

BACKGROUND: In this study, we evaluated the effects of soil incorporation of hairy vetch (HV) or ryeas a green manure on the growth and yields of watermelon and soil nitrate nitrogen in a green house.. METHODS AND RESULTS: HV and rye were cultivated for 151 days after sowing on October 30th and incorporated into soil before transplanting watermelon. The amount of N added by soil incorporation of HV and rye were 79 kg/ha and 88 kg/ha, respectively. Five different N treatments for each of HV and rye were included as follows: green manure, green manure with urea at 25%, 50%or 75%, and 100% ureafor the N recommendation rate. The growth and fruit yield of watermelon were not different among the treatments of both HV and rye. Soil nitrate N content at both HV and rye treatments decreased continuously with the lapse of days after planting (DAP) and was lowest at 75 DAP: 44 mg/kg and 52 mg/kg the for the HV and rye treatment without urea, respectively. CONCLUSION: These results indicate that the N mineralized from the soil incorporated HV or rye accounts for an important portion of N available for the growth and fruit yield of watermelon. It can be suggested that the green manures, comparable to ureacould ensure the yield of watermelon, if soil nitrate N content isabove 40 mg/kg by soil incorporation of HV and rye during watermelon cultivation. However, further studies on the relationship between soil nitrate N content during cultivation periods and the fruit yield of watermelon are required.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.1
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• pp.107-114
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• 1983

The study was carried out to find out the reasonable fertilization method for rice in the area of Irish potato cultivated paddy where has various nutritional disorders and pest problems. The treatment consisted of three different application methods of potato sterns and leaves with 4 levels of nitrogen application in each method. The application of potato sterns and leaves caused more release of $NH_4$ -N in the soils but the growth of rice were slightly hindered by the strongly reduced soil conditions when the nitrogen had been applied more than 10kg/10a. The application of half-dried or semi-decomposed stems and leaves of potatoes were caused to increase ripening ratio and 1,000 grain weight of rice with a relatively high $SiO_2$/N ratio in the rice plant, so the yield of rice increased 3-5% than the plot without potato sterns and leaves. The potash and silicate fertilizer would seem to be effective in the area of Irish potato cultivating paddy field since the contents of extractable potassium and soluble silicate in the soils is lacked. The suitable amount of nitrogen on rice cropping seems to be about 7kg/10a.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.306-306
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• 2009

본 실험은 백세주 주정박이 벼의 생육과 토양 비옥도 개선에 미치는 영향을 조사하였다. 백세주 주정박은 압착된 주박을 재 발효시켜 단식증류기로 증류하여 알코올을 회수 후 발생된다. 실험 처리구는 무시용, 요소, 주정박 처리구로 하였고, 벼 질소비료 표준시비량 11kg N/10a를 기준으로 하여 전량 기비로 사용하였다. 백세주 주정박의 유효성분과 유해성분을 분석하였고, 토양에 주정박을 시용 전 후의 이화학적 분석을 하였다. 벼 실험 품종은 오대벼(Oryza sativa L.)이고, 벼의 생육과 수량 및 미질을 분석하였다. 백세주 주정박의 pH는 3.60, 유기물함량 90.12%, 염농도 0.72ds/cm, 수분함량 88%, 질소 0.21%, 인산 0.24%, 칼리 0.09%로 나타났다. 유해성분(중금속)분석결과 비소 0.03ppm, 크롬 0.09ppm, 구리0.91ppm, 납 0.05ppm, 니켈 0.05ppm, 아연 1.30ppm, 망간 3.28ppm, 철 34.86ppm로 나타났다. 토양이화학적 분석결과 주정박 시용처리구의 유기물함량과 질소 및 인산은 각각 23.0g/kg. 0.11%, 89mg/kg로 무시용과 요소처리구에 비해 유의한 차이를 보였다. 벼 이식 후 140일째 생육분석결과 초장 82.60cm, 옆폭 1.40cm, 옆장 37.70cm, 지상부건물중 59.21g로 다른 2개 처리구에 비해 유의한 차이를 보였다. 벼의 수량은 주정박 시용 처리구가 449.0kg/10a로 무시용 89.66kg/10a와 요소 401.66kg/10a에 비해 유의적인 차이를 보였다. 백세주 주정박 시용을 통해 토양 개량 효과를 기대할 수 있고, 공시 토양의 토양 개량 효과가 벼의 생육에 긍정적인 영향을 끼치는 것으로 나타남에 따라 백세주 주정박의 토양개량제로서의 활용 가능성을 확인하였다.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.282-282
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• 2009

환경오염에 대한 우려 및 안전농산물에 대한 소비자욕구 증대로 유기농산물 시장규모가 최근 3년간 2.8배 성장 추세이다. 친환경농산물 인증면적은 '00년 2,039 ha에서 '07년 122,882 ha로 급격히 증가하고 있으나 생태적 원리에 부합된 벼 재배기술이 부족하며 특히 무경운 논토양에 대한 경영분석 자료는 거의 없는 실정이다. 본 연구는 유기농업기술을 종합적으로 투입한 시범마을을 육성하기 위하여 하동군 양보면 예성마을 1ha를 대상으로 관행농업과 무경운 자운영 피복 벼 기계이앙을 실증하여 경제적인 효과를 검토하였다. 토양 관리를 위해 2007년 9월 10일에 자운영을 3 kg/10a 파종하여 겨울철 토양 생태계를 유지하였고 화학비료나 농약을 사용하지 않았다. 볍씨 소독은 마른 종자를 60 $^{\circ}C$에서 8분간 침지하는 열탕침법을 이용하였으며 논 물담기는 5월 28일경 15 cm 이상 깊게 하여 자운영이 잘 분해되도록 하였다. 기계이앙은 6월 10일경 표면 1 cm 이내의 물 깊이에서 식부장치를 최대한 깊게하고 주수는 주당 5-7주 정도로 실시하였으며 기계이앙 후에는 5일 정도 물을 담지 않고 그대로 두고 그 후 물을 10 cm 이상 깊게 하여 잡초발생을 억제하였다. 중간낙수는 7월 10일경 1회 처리하였고 수확기 낙수는 9월 23일 실시하였다. 무경운 처리구의 이앙전 토양 가밀도는 관행 1.30 g $cm^{-3}$ 비해 0.09 g $cm^{-3}$ 정도 가벼운 것으로 나타났고 공극률은 관행 50.8%에 비해 3.5% 높은 것으로 나타났으며 특히 수분률이 3.5% 높았다. 무경운 자운영 피복 기계이앙 처리구의 잡초발생 건물량은 7월 4일경 피 8.8 g $m^{-2}$, 여뀌 10.8 g $m^{-2}$ 이었으며 9월 18일에는 피 16.0 g $m^{-2}$, 여뀌 12.3 g $m^{-2}$였다. 수확기 관행처리구의 주당 이삭수는 16.7개, 수당립수는 101개, 천립중은 25.4 g, 등숙비율은 82.3%로 수량은 517 kg $10a^{-1}$ 였으며 무경운 자운영 피복 기계이앙은 주당 이삭수가 14.1개, 수당 립수는 103개, 천립중은 26.2 g, 등숙비율은 91.2%로 수량이 456 kg $10a^{-1}$였다. 무경운 자운영피복 벼 기계이앙은 기경작업이나 시비작업 등이 없으므로 노동력이 60% 절감되었으며 농가소득은 5% 증대되었다. 따라서 농업분야 저탄소 녹색성장과 관련하여 자연 생태계를 보전하면서 농가소득을 유지할 수 있는 방법으로 무경운 자운영 피복 벼 기계이앙이 효과적인 것으로 판단되었다.

• Korean Journal of Organic Agriculture
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• v.18 no.1
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• pp.63-74
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• 2010

The present study was carried out to evaluate the effects of organic liquid fertilizer (OLFs) fertigation on the growth and fruit quality of hot pepper (Capsicum annuum L.) cv. 'Nokkwang (Seminis Korea)'. Treatments were given with control (chemical feritilzer), OLF I(fowl dropping : fish meal : soybean meal, 2:1:1), OLF II(fowl dropping : bone meal : soybean meal, 2:1:1), OLF III(fowl dropping : bone meal, 1:1), and OLF IV(fowl dropping : rice bran : soybean meal, 2:1:1). The composition ratio of OLF based on weight to weight. The pH and EC of OLFs according to different material and compositions ranged from 6.5 to 6.8, and from 2.91 to $3.69dS{\cdot}m^{-1}$, respectively. The C/N ratio was the highest as 5.75 in OLF Ⅳ, and there was no difference among the treatments in C/N ratio of the exception of OLF IV. In OLF IV total fruit weight was the highest as 1,558g per plant and total fruit number increased as 23.7% compared to control. The content of capsaicin in the ripened pepper increased with OLF I and II treatments, and decreased with OLF III and IV treatments compared to control of $662mg{\cdot}kg^{-1}$, but the soluble solid content was the highest with OLF IV treatment as $10.0^{\circ}Brix$.