• Journal of Forest and Environmental Science
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• 제30권2호
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• pp.179-188
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• 2014

This research reports the effects of shifting cultivation on soil environment collecting samples from 0-5 cm soil depth from five locations viz. at Burburichhara, Maichchari, Longadu, Sukurchhari and Muralipara in Rangamati district of Chittagong Hill Tracts (CHTs). Soil analyses showed that fungal and bacterial population, microbial respiration and active microbial biomass, maximum water holding capacity, conductivity and moisture contents were significantly (at least $p{\leq}0.05$) lower in shifting cultivated soil compared to adjacent mixed tree plantations at all the sites. On an average in soils of 5 different shifting cultivated lands fungal population was $1.33{\times}10^5$ CFU/g dry soil and bacterial population $1.80{\times}10^7$ CFU/g dry soil and in mixed plantations fungal population was $1.70{\times}10^5$ and bacterial population $2.51{\times}10^7$ CFU/g dry soil. Organic matter and exchangeable Ca and Mg contents were significantly (at least $p{\leq}0.05$) lower and bulk density significantly (at least $p{\leq}0.05$) higher in shifting cultivated land in most of the locations compared to adjacent mixed tree plantations. Ratios of microbial respiration and organic carbon as well as active microbial biomass and organic carbon were distinctly lower and pH higher at 3 locations in shifting cultivated soils compared to mixed plantations. Findings of various soil properties, therefore, suggest that shifting cultivation has deteriorating effects on soil environment.

• 한국유기농업학회지
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• 제19권spc호
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• pp.25-29
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• 2011

This study was performed to analyze the improvement of soil physical property and soil biota characteristics through cultivation of green manure crops for a one-year period before creation of a tea plantation as follows. The study revealed that the contents of available phosphate tended to decrease after sod-culture by green manure cultivation and open-pollination, when compared to the level before cultivation. The ratio soil porosity increased by approximately 30% when Crotalaria juncea and Sorghum bicolar L. Moench were cultivated, while the soil bacteria and fungi also increased. In a research on microfauna using a pit fall trap, the population number of the microfauna was 174 of 27 species in the plot of open-pollinated sod-culture and no organic matter application, and 268 of 26 species in the plot of Sorghum bicolar L. Moench. Consequently, the culturing tool of Crotalaria juncea recorded the highest level of species diversity at 2.5, the evenness index at 3.7 and richness at 4.6, with the lowest level of a dominance index. The ecological quotient of microfauna was 0.76 in the plot of Sorghum bicolar L. Moench, and 0.63 in the plot of Crotalaria juncea.

• 한국유기농업학회지
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• 제23권4호
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• pp.963-974
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• 2015

유기농 시설채소 재배지 토양의 물리적 특성조사는 전국 33개 농가 포장에서 2014년 8월부터 11월 사이에 조사하였다. 시설채소 재배지 선정은 엽채류인 상추(Lactuca sativa L.)와 잎들깨(Perilla frutescens var. japonica Hara), 과채류인 오이(Cucumis sativus L.), 딸기(Fragaria ananassa L.), 토마토(Lycopersicon spp.)를 경작하는 채소 종류별 5~8개 농가씩 선정하여 경도, 작토심 및 삼상 등 토양의 물리적 특성을 현장조사와 실험실내에서 분석하였다. 연구결과 작토심은 30~50 cm 범위로 평균 36 cm이었고, 재배되는 채소의 종류에 따라서 다소 차이가 있었다. 토양의 경도는 표토에서 $0.17{\pm}0.15{\sim}1.34{\pm}1.02$, 심토에서 $0.55{\pm}0.34{\sim}1.15{\pm}0.62$로 모두 매우 우수하였으며, 표토와 심토간에는 큰 차이가 없었으나 엽채류와 과채류 간에는 통계적으로 유의적인 차이를 나타내었다. 관입저항성은 뿌리 신장과 작물 수량을 결정짓는 토양의 물리적 특성중의 하나이다. 관입저항성은 엽채류 재배지에서 답압으로 인하여 다소 높게 나타났다. 토양의 삼상은 유기농 시설재배지 토양에서 동적이고, 전형적으로 변화되었다. 공극률은 $54.2{\pm}2.2{\sim}60.3{\pm}2.4%$ 범위로 높은 경향을 나타내었다. 이상의 결과를 요약해 보면 유기농 시설채소 재배지 토양은 토심은 깊어지고, 고상과 경도(흙의 단단함), 용적밀도(토양 단위 용적당 질량)는 낮아졌으며, 공극률(토양속 공간함유율)은 높아지는 등 유기농 시설재배지 토양의 물리성이 양호하였다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2000년도 춘계임시총회 및 학술발표대회
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• pp.45-51
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• 2000

According to the research of the cultivation result on the spot farmers for 5 years in order to investigate its cultivation conditions and problems of Lycium chinense Mill, the development of the variety with early mature, pest tolerance, and high yielding is urgent and it is call for the development of rooted cutting cultivation by testing of bed soil, growth regulator and cutting times. The development of cultivation method with planting year, planting density, supplementary period and amounts of supplementary of Lycium chinense Mill planted in growing field are required and for the disease and the effective control of disease and insect pest resistance is needed by auxotrophic fertilizing and organic agricultural method, met by agricultural chemicals.

• Environmental Engineering Research
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• 제24권2호
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• pp.271-278
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• 2019

Mass cultivation of microalgae is necessary to achieve economically feasible production of microalgal biodiesel. However, the high cost of nutrients is a major limitation. In this study, corncob extract (CCE) was used as an inorganic and organic nutrient source for the mass cultivation of Chlorella vulgaris (C. vulgaris). Chemical composition analysis of CCE revealed that it contained sufficient nutrients for mixotrophic cultivation of C. vulgaris. The highest specific grow rate of C. vulgaris was obtained at pH of 7-8, temperature of $25-30^{\circ}C$, and CCE amount of 5 g/L. In the analysis using various growth models, Luong model was found to be the most suitable empirical formula for mass cultivation of C. vulgaris using CCE. Analysis of biomass and production of triacyglycerol showed that microalgae grown in CCE medium produced more than 17.23% and 3% more unsaturated fatty acids than cells cultured in Jaworski's Medium. These results suggest that growing microalgae in CCE-supplemented medium can increase lipid production. Therefore, CCE, agricultural byproduct, has potential use for mass cultivation of microalgae.

• 한국환경과학회지
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• 제30권2호
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• pp.145-152
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• 2021

Soil conservation management is necessary for sustainable agriculture, in highland areas, and cover crops are one of the best soil conservation methods for slopes. In this study, we evaluated the effects of alfalfa cultivation on maize production, as well as soil conservation and quality. There was an outstanding soil conservation effect with alfalfa cultivation in the fallow and maize growing seasons. In particular, alfalfa cultivation reduced soil loss by up to 98% compared with bare field. It also increased the activities of soil microorganisms and the supply of organic matter. Maize production with alfalfa cultivation showed no significant differences in yield. In conclusion, alfalfa is an advantageous perennial cover crop in highland agricultural slope areas, which can have positive effects on soil quality and conservation, as well as maize production.

• 한국유기농업학회지
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• 제23권3호
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• pp.595-604
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• 2015

논토양의 화학적 특성은 경작지대 및 재배방법에 따라 차이가 나타났다. 토양 pH는 전라남도 간척지의 관행재배지를 제외하고 대체적으로 적정기준(pH 5.5~6.5) 범위로 나타났다. EC는 이모작재배지에서 다소 높게 나타나긴 하였으나 우려할 수준은 아니었고, 이모작재배지에서 유효인산(avail. $P_2O_5$) 함량이 매우 높게 나타나 담수상태에서 유효인산의 하천 유출로 인한 2차 오염이 우려된다. 토양유기물(SOM) 함량은 전라북도 지역 논토양에서는 대체적으로 적정기준 ($25{\sim}30g\;kg^{-1}$) 보다 낮게 나타났으나, 전라남도 지역 논토양은 적정범위 이거나 초과하는 것으로 나타났다. CEC는 일부 재배지를 제외하고는 적정기준($10{\sim}15cmol_c\;kg^{-1}$) 범위로 나타났고, 유효규산 (avail. $SiO_2$) 함량은 적정기준($157{\sim}180mg\;kg^{-1}$)보다 매우 높게 나타나는 경우도 있었으나, 대체로 경작 지대 및 재배방법에 따라 특이적 함량차이가 나타났다. 토양 화학성 상관성 분석에서 EC와 치환성 K, Ca, Mg, Na 이온은 유의성 있는 정의 상관관계로 나타났다. SOM 함량과 CEC는 유의성 있는 정의상관관계가 나타났고,avail. $SiO_2$는 pH, EC, 치환성 양이온(exch. K, Ca, Mg, Na), CEC와 유의성 있는 정의 상관관계를 보였다. 그러나 T-N은 치환성 K 및 Mg 이온과는 유의한 부의 상관관계를 나타내었다. 이러한 결과를 토대로 비옥도의 기준이 되는 대표적인 논토양을 설정하는데 귀중한 자료가 될 것으로 판단된다.

• 한국유기농업학회지
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• 제19권spc호
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• pp.149-152
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• 2011

To improve the soil condition for no-tillage organic pepper cultivation, four different green manure crops were cultivated. Fertilizer supply was depended on the biomass of the cultivated green manure crops, nitrogen supplies were 314kg in Vicia villosa and 341kg $ha^{-1}$ in Vicia angustifolia. In the microbial community analyzed by phospholipid fatty acid (PLFA) method, soil microbe populations were different among the green manure crops and fungi group was increased at Vicia angustifloia and Vicia villosa. The biological ratio indexes of fatty acids in the soils, the ratio of Gram-negative to Gram-positive bacterial PLFA and Ratio of aerobes to anaerobes were high at Vicia hirsute and Vicia tetrasperma suggesting the enrich of the aerobic conditions. The ratio of saturated to unsaturated fatty acids increased at Vicia angustifloia and Vicia villosa suggesting anaerobic conditions. Abundant biomass and uncomposted organic matter, the ratio of fungi to bacteria was increased at Vicia angustifloia and Vicia villosa.

• 한국약용작물학회지
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• 제27권1호
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• pp.1-8
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• 2019

Background: This study was conducted to investigate the effects of fertilization with the application of mixed organic matter after cultivating green manure crops on the growth and saponin content of Codonopsis lanceolata Trautv. Methods and Results: Five type of cultivation of green manure crops were done: hairy vetch as a single seedling crop (HV), hairy vetch and rye as a mixture of seedling (HV/R), additional fertilization with mixed organic matter after cultivation of a seedling mixture (HV/R/MO), chemical fertilizer (CF), and a non-treated control (NT). The total nitrogen content was the highest in the HV/R/MO treatment, followed by the HV, CF, HV/R and NT treatments, respectively. Nitrogen fixation was higher in the single seedling treatment with hairy vetch (HV) than in the treatment with a mixture of hairy vetch and rye seedling (HV/R). Moreover, the growth of C. lanceolata was greatly increased by the application of additional fertilizer after treatment with the mixture of hairy vetch and rye seedlings. The HV/R/MO treatment produced the highest total lancemaside content among the treatments, followed by HV, HV/R, CF, and NT, respectively. Conclusions: It was verified that C. lanceolata experienced superior growth with the application of mixed organic matter as additional fertilizer after the cultivation of green manure crops, and the content of its major saponins, lancemasides were also increased by this treatment.

• 한국유기농업학회:학술대회논문집
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• 한국유기농학회 2009년도 하반기 학술대회
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• pp.103-113
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• 2009

유기농 및 일반재배 대두를 다양한 용매에서 추출하여 그 추출물에 대한 항산화 효과, 항염증 효과, 대식세포의 세포사멸 보호 효과, 그리고 알레르기 저해효과를 비교하였다. DPPH 법과 SOD 효소의 활성 측정으로 항산화 능력을 평가하였으며, 항염증 효과는 LPS로 유도시킨 Raw 264.7 세포주에서 염증 매개 단백질인 Cox-2와 iNOS의 발현량을 western blotting으로 조사하여 분석하였다. 또한 대식세포 보호 효과를 세포사멸 조절 단백질인 Bcl-xl의 발현량 조사로 평가하였고, 1 mM $H_2O_2$ 처리로 유도되는 세포사멸의 보호효과를 세포 수 측정법으로 조사하였다. 항알레르기 효과는 흰쥐의 비만세포인 RBL-2H3 세포주를 사용하여 IgE로 매개되는 비만세포의 탈과립화를 OPT assay로 측정하여 분석하였다. 그 결과, 일반 재배보다 유기 재배 대두 추출물이 더 좋은 항산화, 세포사멸 보호, 항염증 효과를 나타내었다. 특히 유기농 대두의 열수 추출물은 LPS로 유도시킨 염증반응을 효과적으로 억제하는 것으로 나타났다. 그러나 항알레르기 효과는 모든 추출물에서 히스타민 유리량이 약간 감소하는 것으로 나타나 유기농과 일반재배의 차이를 확인할 수 없었다. 대두에는 많은 유용한 생리활성물질 뿐 만 아니라 알레르기 유발 물질도 존재하는 것으로 알려져 있지만 조추출물 상태에서는 특이적인 알레르기 유발보다 오히려 항알레르기 효과가 나타났다. 결론적으로, 만성 염증 및 천식, 그리고 아토피피부염과 같은 염증관련 질환에는 유기재배된 대두가 일반 대두보다 좋은 억제 효과를 가지고 있다고 판단된다.