• 한국환경농학회지
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• 제3권1호
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• pp.22-29
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• 1984

토양(土壤)에 의한 linuron, bentazon, trifluralin 및 butachlor의 흡착(吸着)을 나타내는데 있어서 Freundlich adsorption isotherm이 사용되었으며, 실험결과(實驗結果)를 요약(要約)하면 아래와 같다. 토양(土壤)에 의한 linuron의 흡착(吸着)은 토양성분중(土壤成分中) 유기물(有機物)의 함량(含量)과 직접적인 관계(關係)가 있으며, 유기물(有機物)의 함량(含量)이 증가(增加)함에 따라 linuron의 흡착(吸着)도 증가(增加)하였다. Bentazon은 토양유기물(土壤有機物)이나 점토(粘土)의 함량(含量)에 따라 뚜렷한 상관(相關)이 없었으며, 오히려 유기물함양(有機物含量)이 증가(增加)됨에 따라 흡착(吸着)은 감소(減少)하는 경향(傾向)이었다. 이러한 현상은 bentazon이 토양용액중(土壤溶液中)에서 음하전(陰荷電)을 띠어 bentazon분자(分子)와 음하전(陰荷電)을 띤 토양표면간(土壤表面間)의 반발현상(反撥現象) 때문인 것으로 추정(推定)되었다. Trifluralin과 butachlor는 토양유기물함량(土壤有機物含量) 및 C.E.C.와 매우 높은 상관성(相關性)을 보였으나, 점토함량(粘土含量)과는 뚜렷한 경향(傾向)이 없었다. 각 공시농약(供試農藥)에 대한 흡착(吸着)은 trifluralin이 가장 많았고 다음으로는 linuron, butachlor, bentazon순(順) 이었다.

• 한국유기농업학회지
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• 제2권1호
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• pp.37-46
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• 1993

본 연구는 1992년도 브라질에 개최되는 국제환경회의에 UNDP의 요청에 의하여 이루어진 것이다. 한국의 유기농민단체들 가운데에서 화학비료와 농약을 전혀 사용하지 않고 영농을 경영하고 있는 정농회의 역사적인 발전과정을 조사하여 보았다. 그리고 정농회 회원들에 의하여 생산된 유기농산물과 일반 농산물 사이에 가격수준을 비교하여 보았다. 아직도 유기농업에 종사하고 있는 회원수는 500여명에 달하고 있다. 그러나 핵심 구성원수는 50여명에 불과하다. 정농회는 약 17년의 역사를 가지고 있는 유기농민단체이다. 유기농산물의 가격수준은 일반농산물과 비교하여 약 20% 정도의 수준을 나타내고 있다. 그러나 유통과정에서 소비자들에게 직접 배달하여 주거나 또는 직판장에서 직판하고 있는 실정이다. 앞으로 한국의 유기농업을 발전시키기 위하여 좀더 많은 실증적인 연구가 이루어져야 할 것으로 기대하는 바이다.

• 한국유기농업학회지
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• 제14권3호
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• pp.325-331
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• 2006

The experiment fields consisted of five plots as follows; 2, 4, and $8\;tons{\cdot}ha^{-1}$ citrus skin in combination with starch sludge and pig manure mixing compost (CSSP), $4\;ton{\cdot}ha^{-1}$ fermented pig manure compost (FPMC) treated plot, and untreated control. Plant height and stem diameter were significantly increased by CSSP. Most of all, average tuber weight and tuber yield per plant were significantly increased in 4 and $8\;tons{\cdot}ha^{-1}$ CSSP plots compared to the other plots. Marketable tuber (>50 g fresh weight) yield were superior in order of 4 and $8\;tons{\cdot}ha^{-1}$ CSSP plot, $4\;tons{\cdot}ha^{-1}$ FPMC plot, and $2\;tons{\cdot}ha^{-1}$ CSSP plot.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2001년도 High Temperature Superconductivity Vol.XI
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• pp.25-25
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• 2001

• 펄프종이기술
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• 제38권2호
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• pp.9-15
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• 2006

Neutral sizing is required for linerboard to solve the troubles in strength and process caused by recycled raw materials. AKD sizing efficiency can be influenced by process condition like white water quality, fines retention and so on. Therefore, this study was aimed to evaluate sizing performance of general and fast cure type AKDs using process water obtained from linerboard mill. To evaluate effect of process water quality on AKD sizing, white water was diluted with tap water at the different dilution ratios and UKP slurry was sized using the prepared water. Also, effects of inorganic and organic ion material on sizing were examined. When white water was used for stock forming, UKP sheet showed very low sizing degree. Sizing degree of sheet was increased with increase of dilution ratio because water quality was improved. Especially anionic organic material had a greater influence on AKD sizing than inorganic material. When white water quality was deteriorated, fast cure type AKD showed superior sizing performance to general type AKD.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.II
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• pp.236-245
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• 2000

The feasibility of precision farming for small sized fields was studied by determining fertilizing amount of nitrogenous and calcareous to a cite specific region. A detailed soil survey at three experimental fields of 672㎡, 300㎡ and 140㎡ revealed a considerable spatial variation of the pH and organic matter(OM) levels. Soil organic matter was measured using Walkley-Black method and soil pH was measured with a pH sensor. Soil sample was obtained by Grid Node Sampling Method. The soil sampling depth was 10 - 20 cm from the soil surface. To display soil nutrient variation, a soil map was made using Geographic Information System (GIS) software. In soil mapping, soil data between nodes was interpolated using Inverse Distance Weighting (IDW) method. The variation was about 1 - 1.8 in pH value and 1.4 -7 % in OM content. Fertilizing Amount of nitrogenous and calcareous was determined by the fertilizing equation which was proposed by National Institute of Agricultural Science and Technology.(NIAST). The variation of fertilizing amount was about 3 - 11 kg/10a in nitrogenous and 70 - 140 kg/10a in calcareous. The results showed a feasibility of precision fertilizing for small size fields.

• 농업과학연구
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• 제49권3호
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• pp.463-481
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• 2022

Phosphorous (P) is considered to be one of the key essential elements demanded by crop plants. Approximately 70 - 90% of phosphatic fertilizers applied to crops are fixed in soil as Ca, Fe, and Al metal cations, which are insoluble and thus not readily available for plant uptake. Therefore, most soils are deficient in plant available P. This is usually rectified by applying phosphate fertilizers continuously, although this is not economically viable or environmentally acceptable. The present paper reviews the mechanisms involved with phosphate solubilization and mineralization by phosphate solubilizing microorganisms (PSMs) with the associated factors that determine the success. PSMs are effectively involved in mediating the bioavailability of soil P. Their contribution includes mineralization of organic P solubilization of inorganic P minerals, and storing sizable amounts of P in biomass through different mechanisms such as the production of organic and inorganic acids, H₂S, siderophores, exopolysaccharides, and production of enzymes such as phosphatases, phytase, and phosphonatases/C-P lyases, which are capable of chelating the metal ions, forming complexes, and making plant available P. PSMs manifest a wide range of metabolic functions in different environments, resulting in significantly higher plant growth, enhanced soil properties, and increased biological activities. Therefore, development of bio-inoculants with efficient novel PSM strains and further investigations on exploring such strains from diverse ecological niches with multifunctional plant-growth-promoting traits are needed.

• Journal of Forest and Environmental Science
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• 제28권4호
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• pp.212-219
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• 2012

An experiment was set to understand the seedlings growth and nodulation capabilities of five potentially important leguminous agroforestry tree species of Bangladesh in response to application of organic fertilizer. Study was carried out in nursery bed on the seedlings of Acacia mangium Willd., Acacia hybrid, Acacia auriculiformis A. Cunn. ex Benth, Albizia lebbeck (L.) Benth. and Leucaena leucocephala (Lam.) de Wit. after sowing their seeds in polybags filled with different medium. Farmyard manure or decomposed cow dung was applied as the source of organic fertilizer with other potting media. The growth and nodulation performance of seedlings of the selected species were measured three moths after the first seed was emerged. The different soil: organic manure ratios' used during the experiment were, 1:1, 2:1 and 3:1. The effects of organic fertilizer on growth and nodulation were compared to that of seedlings grown in control. The results revealed a positive correlation between seedling growth and the different doses of organic fertilization (i.e. seedling growth was enhanced significantly with different treatments containing higher proportion of organic fertilizer). In few cases a negative effect was observed after applying higher levels of organic manure. It was also apparent that the nodulation in terms of nodule number and size was inhibited significantly by the application of organic fertilizer.

• 한국환경농학회지
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• 제42권4호
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• pp.358-370
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• 2023

Composting has been proposed for the management of organic waste, and the resulting products can be used as soil amendments and fertilizer. However, the emissions of greenhouse gases (GHGs) such as CO₂, CH₄, and N₂O produced in composting are of considerable concern. Hence, various additives have been developed and adopted to control the emissions of GHGs. This review presents the different additives used during composting and summarizes the effects of additives on GHGs during composting. Thirty-four studies were reviewed, and their results showed that the additives can reduce cumulative CO₂, CH₄, and N₂O emission by 10.5%, 39.0%, and 28.6%, respectively, during composting. Especially, physical additives (e.g., biochar and zeolite) have a greater effect on mitigating N₂O emissions during composting than do chemical additives (e.g., phosphogypsum and dicyandiamide). In addition, superphosphate had a high CO₂ reduction effect, whereas biochar and dicyandiamide had a high N₂O reduction effect. This implies that the addition of superphosphate, biochar, and dicyandiamide during composting can contribute to mitigating GHG emissions. Further research is needed to find novel additives that can effectively reduce GHG emissions during composting.

• 한국토양비료학회지
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• 제45권6호
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• pp.998-1003
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• 2012

Pantoea agglomerans DSM3493 was isolated from green house soils collected from Chungchugnam-do province, Gongju-Gun area in South Korea and phosphate solubilization and organic acid production of the strain were assessed using three types of insoluble phosphate sources (Ca phosphate, Fe phosphate and Al phosphate) under three different pH conditions (7, 8 and 9). The highest Ca phosphate solubilization ($651{\mu}g\;mL^{-1}$) was recorded at pH 7 followed by pH 8 and 9 (428 and $424{\mu}g\;mL^{-1}$ respectively). The solubilization rate was found to be 80.4, 98.1 and $88.7{\mu}g\;mL^{-1}$ (for Fe phosphate containing medium) and 9.3, 12.1 and $29.8{\mu}g\;mL^{-1}$ (for the Al phosphate containing medium) respectively at pH 7, 8 and 9. Though increasing pH of the medium caused reduction in the rate of solubilization of Ca phosphate, solubilization of Fe and Al phosphates enhanced with increasing pH. By contrast, the highest amount of organic acid was produced with Ca phosphate while the lowest was recorded with the presence of Al phosphate. Among the organic acids, gluconic acid production was found to be the highest, followed by oxalic acid and citric acid regardless the source of phosphate. Results can thus be concluded that the production of organic acids appears to play a significant role in the inorganic phosphate solubilization.